feat: add support for new arrow types and enhance use case diagram features

on-behalf-of: @Mermaid-Chart <hello@mermaidchart.com>

.build/antlr-cli.ts

@@ -0,0 +1,92 @@
+/* eslint-disable no-console */
+
+import { exec } from 'node:child_process';
+import { promisify } from 'node:util';
+import { resolve, dirname } from 'node:path';
+import { readFile, mkdir, access } from 'node:fs/promises';
+import { existsSync } from 'node:fs';
+
+const execAsync = promisify(exec);
+
+interface AntlrGrammarConfig {
+  id: string;
+  grammar: string;
+  outputDir: string;
+  language: string;
+  generateVisitor?: boolean;
+  generateListener?: boolean;
+}
+
+interface AntlrConfig {
+  projectName: string;
+  grammars: AntlrGrammarConfig[];
+  mode: string;
+}
+
+export async function generateFromConfig(configFile: string): Promise<void> {
+  const configPath = resolve(configFile);
+
+  if (!existsSync(configPath)) {
+    throw new Error(`ANTLR config file not found: ${configPath}`);
+  }
+
+  const configContent = await readFile(configPath, 'utf-8');
+  const config: AntlrConfig = JSON.parse(configContent);
+
+  const configDir = dirname(configPath);
+
+  for (const grammarConfig of config.grammars) {
+    await generateGrammar(grammarConfig, configDir);
+  }
+}
+
+async function generateGrammar(grammarConfig: AntlrGrammarConfig, baseDir: string): Promise<void> {
+  const grammarFile = resolve(baseDir, grammarConfig.grammar);
+  const outputDir = resolve(baseDir, grammarConfig.outputDir);
+
+  // Check if grammar file exists
+  try {
+    await access(grammarFile);
+  } catch {
+    throw new Error(`Grammar file not found: ${grammarFile}`);
+  }
+
+  // Ensure output directory exists
+  await mkdir(outputDir, { recursive: true });
+
+  // Build ANTLR command arguments
+
+  // eslint-disable-next-line @cspell/spellchecker
+  const args = ['antlr-ng', `-Dlanguage=${grammarConfig.language}`];
+
+  if (grammarConfig.generateVisitor) {
+    args.push('--generate-visitor');
+  }
+
+  if (grammarConfig.generateListener) {
+    args.push('--generate-listener');
+  }
+
+  args.push('-o', `"${outputDir}"`, `"${grammarFile}"`);
+
+  const command = `npx ${args.join(' ')}`;
+
+  try {
+    await execAsync(command);
+    console.log(`Generated ANTLR files for ${grammarConfig.id}`);
+  } catch (error) {
+    console.error(`Failed to generate ANTLR files for ${grammarConfig.id}:`);
+    throw error;
+  }
+}
+
+// CLI interface
+if (import.meta.url === `file://${process.argv[1]}`) {
+  const configFile = process.argv[2] || './packages/parser/antlr-config.json';
+  try {
+    await generateFromConfig(configFile);
+    console.log('ANTLR generation completed successfully!');
+  } catch (error) {
+    console.error('ANTLR generation failed:', error.message);
+  }
+}

.build/generateAntlr.ts

@@ -0,0 +1,5 @@
+import { generateFromConfig } from './antlr-cli.js';
+
+export async function generateAntlr() {
+  await generateFromConfig('./packages/parser/antlr-config.json');
+}

.build/jsonSchema.ts

@@ -28,6 +28,7 @@ const MERMAID_CONFIG_DIAGRAM_KEYS = [
   'packet',
   'architecture',
   'radar',
+  'usecase',
 ] as const;
 
 /**

.changeset/brave-memes-flash.md

@@ -1,5 +0,0 @@
----
-'mermaid': patch
----
-
-fix: Support edge animation in hand drawn look

.changeset/busy-mirrors-try.md

@@ -1,5 +0,0 @@
----
-'mermaid': patch
----
-
-fix: Resolved parsing error where direction TD was not recognized within subgraphs

.changeset/chilly-words-march.md

@@ -1,5 +0,0 @@
----
-'mermaid': patch
----
-
-fix: Correct viewBox casing and make SVGs responsive

.changeset/curly-apes-prove.md

@@ -1,5 +0,0 @@
----
-'mermaid': patch
----
-
-fix: Improve participant parsing and prevent recursive loops on invalid syntax

.changeset/deep-pumas-run.md

@@ -0,0 +1,5 @@
+---
+'mermaid': patch
+---
+
+chore: Fix mindmap rendering in docs and apply tidytree layout

.changeset/four-eyes-wish.md

@@ -0,0 +1,5 @@
+---
+'mermaid': patch
+---
+
+fix: Ensure edge label color is applied when using classDef with edge IDs

.changeset/gold-ducks-sort.md

@@ -1,5 +0,0 @@
----
-'mermaid': patch
----
-
-fix: Proper separation between strings and markdown strings

.changeset/moody-fans-try.md

@@ -0,0 +1,5 @@
+---
+'mermaid': patch
+---
+
+fix: Resolve gantt chart crash due to invalid array length

.changeset/proud-colts-smell.md

@@ -0,0 +1,5 @@
+---
+'mermaid': minor
+---
+
+feat: Add IDs in architecture diagrams

.changeset/revert-marked-dependency.md

@@ -0,0 +1,9 @@
+---
+'mermaid': patch
+---
+
+chore: revert marked dependency from ^15.0.7 to ^16.0.0
+
+- Reverted marked package version to ^16.0.0 for better compatibility
+- This is a dependency update that maintains API compatibility
+- All tests pass with the updated version

.changeset/short-seals-sort.md

@@ -1,5 +0,0 @@
----
-'mermaid': minor
----
-
-feat: allow to put notes in namespaces on classDiagram

.cspell/code-terms.txt

@@ -1,5 +1,3 @@
-!viewbox
-# It should be viewBox
 # This file contains coding related terms
 ALPHANUM
 antiscript
@@ -145,6 +143,9 @@ typeof
 typestr
 unshift
 urlsafe
+usecase
+Usecase
+USECASE
 verifymethod
 VERIFYMTHD
 WARN_DOCSDIR_DOESNT_MATCH

.cspell/libraries.txt

@@ -64,7 +64,6 @@ rscratch
 shiki
 Slidev
 sparkline
-speccharts
 sphinxcontrib
 ssim
 stylis

.esbuild/build.ts

@@ -4,6 +4,7 @@ import { packageOptions } from '../.build/common.js';
 import { generateLangium } from '../.build/generateLangium.js';
 import type { MermaidBuildOptions } from './util.js';
 import { defaultOptions, getBuildConfig } from './util.js';
+import { generateAntlr } from '../.build/generateAntlr.js';
 
 const shouldVisualize = process.argv.includes('--visualize');
 
@@ -95,6 +96,7 @@ const buildTinyMermaid = async () => {
 
 const main = async () => {
   await generateLangium();
+  await generateAntlr();
   await mkdir('stats', { recursive: true });
   const packageNames = Object.keys(packageOptions) as (keyof typeof packageOptions)[];
   // it should build `parser` before `mermaid` because it's a dependency

.esbuild/util.ts

@@ -71,9 +71,6 @@ export const getBuildConfig = (options: MermaidBuildOptions): BuildOptions => {
 
   const external: string[] = ['require', 'fs', 'path'];
   const outFileName = getFileName(name, options);
-  const { dependencies, version } = JSON.parse(
-    readFileSync(resolve(__dirname, `../packages/${packageName}/package.json`), 'utf-8')
-  );
   const output: BuildOptions = buildOptions({
     ...rest,
     absWorkingDir: resolve(__dirname, `../packages/${packageName}`),
@@ -85,13 +82,15 @@ export const getBuildConfig = (options: MermaidBuildOptions): BuildOptions => {
     chunkNames: `chunks/${outFileName}/[name]-[hash]`,
     define: {
       // This needs to be stringified for esbuild
-      'injected.includeLargeFeatures': `${includeLargeFeatures}`,
-      'injected.version': `'${version}'`,
+      includeLargeFeatures: `${includeLargeFeatures}`,
       'import.meta.vitest': 'undefined',
     },
   });
 
   if (core) {
+    const { dependencies } = JSON.parse(
+      readFileSync(resolve(__dirname, `../packages/${packageName}/package.json`), 'utf-8')
+    );
     // Core build is used to generate file without bundled dependencies.
     // This is used by downstream projects to bundle dependencies themselves.
     // Ignore dependencies and any dependencies of dependencies

.github/workflows/release.yml

@@ -42,4 +42,5 @@ jobs:
           publish: pnpm changeset:publish
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
           NPM_CONFIG_PROVENANCE: true

.github/workflows/validate-lockfile.yml

@@ -1,7 +1,7 @@
 name: Validate pnpm-lock.yaml
 
 on:
-  pull_request_target:
+  pull_request:
     paths:
       - 'pnpm-lock.yaml'
       - '**/package.json'
@@ -15,8 +15,13 @@ jobs:
         uses: actions/checkout@v4
         with:
           fetch-depth: 0
-          ref: ${{ github.event.pull_request.head.sha }}
-          repository: ${{ github.event.pull_request.head.repo.full_name }}
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 20
+
+      - uses: pnpm/action-setup@a7487c7e89a18df4991f7f222e4898a00d66ddda # v4.1.0
 
       - name: Validate pnpm-lock.yaml entries
         id: validate # give this step an ID so we can reference its outputs
@@ -50,41 +55,16 @@ jobs:
             exit 1
           fi
 
-      - name: Find existing lockfile validation comment
-        if: always()
-        uses: peter-evans/find-comment@v3
-        id: find-comment
-        with:
-          issue-number: ${{ github.event.pull_request.number }}
-          comment-author: 'github-actions[bot]'
-          body-includes: 'Lockfile Validation Failed'
-
       - name: Comment on PR if validation failed
         if: failure()
-        uses: peter-evans/create-or-update-comment@v5
+        uses: peter-evans/create-or-update-comment@v4
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
           issue-number: ${{ github.event.pull_request.number }}
-          comment-id: ${{ steps.find-comment.outputs.comment-id }}
-          edit-mode: replace
           body: |
-            ❌ **Lockfile Validation Failed**
-
             The following issue(s) were detected:
             ${{ steps.validate.outputs.errors }}
 
             Please address these and push an update.
 
             _Posted automatically by GitHub Actions_
-
-      - name: Delete comment if validation passed
-        if: success() && steps.find-comment.outputs.comment-id != ''
-        uses: actions/github-script@v7
-        with:
-          github-token: ${{ secrets.GITHUB_TOKEN }}
-          script: |
-            await github.rest.issues.deleteComment({
-              owner: context.repo.owner,
-              repo: context.repo.repo,
-              comment_id: ${{ steps.find-comment.outputs.comment-id }},
-            });

.gitignore

@@ -51,5 +51,8 @@ demos/dev/**
 tsx-0/**
 vite.config.ts.timestamp-*
 
-# autogenereated by langium-cli
+# autogenereated by langium-cli and antlr-cli
 generated/
+
+# autogenereated by antlr-cli
+.antlr/

.vite/build.ts

@@ -10,6 +10,7 @@ import type { TemplateType } from 'rollup-plugin-visualizer/dist/plugin/template
 import istanbul from 'vite-plugin-istanbul';
 import { packageOptions } from '../.build/common.js';
 import { generateLangium } from '../.build/generateLangium.js';
+import { generateAntlr } from '../.build/generateAntlr.js';
 
 const visualize = process.argv.includes('--visualize');
 const watch = process.argv.includes('--watch');
@@ -78,8 +79,6 @@ export const getBuildConfig = ({ minify, core, watch, entryName }: BuildOptions)
     },
     define: {
       'import.meta.vitest': 'undefined',
-      'injected.includeLargeFeatures': 'true',
-      'injected.version': `'0.0.0'`,
     },
     resolve: {
       extensions: [],
@@ -96,6 +95,10 @@ export const getBuildConfig = ({ minify, core, watch, entryName }: BuildOptions)
       }),
       ...visualizerOptions(packageName, core),
     ],
+    define: {
+      // Needs to be string
+      includeLargeFeatures: 'true',
+    },
   };
 
   if (watch && config.build) {
@@ -121,6 +124,7 @@ const main = async () => {
 };
 
 await generateLangium();
+await generateAntlr();
 
 if (watch) {
   await build(getBuildConfig({ minify: false, watch, core: false, entryName: 'parser' }));

Dockerfile

@@ -5,7 +5,7 @@ USER 0:0
 RUN corepack enable \
     && corepack enable pnpm
 
-RUN apk add --no-cache git~=2.43 \
+RUN apk add --no-cache git~=2.43.4 \
     && git config --add --system safe.directory /mermaid
 
 ENV NODE_OPTIONS="--max_old_space_size=8192"

cypress/helpers/util.ts

@@ -6,7 +6,6 @@ interface CypressConfig {
   listUrl?: boolean;
   listId?: string;
   name?: string;
-  screenshot?: boolean;
 }
 type CypressMermaidConfig = MermaidConfig & CypressConfig;
 
@@ -91,7 +90,7 @@ export const renderGraph = (
 
 export const openURLAndVerifyRendering = (
   url: string,
-  { screenshot = true, ...options }: CypressMermaidConfig,
+  options: CypressMermaidConfig,
   validation?: any
 ): void => {
   const name: string = (options.name ?? cy.state('runnable').fullTitle()).replace(/\s+/g, '-');
@@ -99,16 +98,12 @@ export const openURLAndVerifyRendering = (
   cy.visit(url);
   cy.window().should('have.property', 'rendered', true);
   cy.get('svg').should('be.visible');
-  // cspell:ignore viewbox
-  cy.get('svg').should('not.have.attr', 'viewbox');
 
   if (validation) {
     cy.get('svg').should(validation);
   }
 
-  if (screenshot) {
-    verifyScreenshot(name);
-  }
+  verifyScreenshot(name);
 };
 
 export const verifyScreenshot = (name: string): void => {

cypress/integration/rendering/classDiagram-v2.spec.js

@@ -562,20 +562,6 @@ class C13["With Città foreign language"]
       `
     );
   });
-  it('should add notes in namespaces', function () {
-    imgSnapshotTest(
-      `
-      classDiagram
-      note "This is a outer note"
-      note for C1 "This is a outer note for C1"
-      namespace Namespace1 {
-        note "This is a inner note"
-        note for C1 "This is a inner note for C1"
-        class C1
-      }
-      `
-    );
-  });
   it('should render a simple class diagram with no members', () => {
     imgSnapshotTest(
       `

cypress/integration/rendering/classDiagram-v3.spec.js

@@ -709,20 +709,6 @@ class C13["With Città foreign language"]
       `
     );
   });
-  it('should add notes in namespaces', function () {
-    imgSnapshotTest(
-      `
-      classDiagram
-      note "This is a outer note"
-      note for C1 "This is a outer note for C1"
-      namespace Namespace1 {
-        note "This is a inner note"
-        note for C1 "This is a inner note for C1"
-        class C1
-      }
-      `
-    );
-  });
   it('should render a simple class diagram with no members', () => {
     imgSnapshotTest(
       `

cypress/integration/rendering/flowchart-handDrawn.spec.js

@@ -1029,19 +1029,4 @@ graph TD
       }
     );
   });
-
-  it('FDH49: should add edge animation', () => {
-    renderGraph(
-      `
-      flowchart TD
-          A(["Start"]) L_A_B_0@--> B{"Decision"}
-          B --> C["Option A"] & D["Option B"]
-          style C stroke-width:4px,stroke-dasharray: 5
-          L_A_B_0@{ animation: slow } 
-          L_B_D_0@{ animation: fast }`,
-      { look: 'handDrawn', screenshot: false }
-    );
-    cy.get('path#L_A_B_0').should('have.class', 'edge-animation-slow');
-    cy.get('path#L_B_D_0').should('have.class', 'edge-animation-fast');
-  });
 });

cypress/integration/rendering/flowchart-v2.spec.js

@@ -1174,8 +1174,8 @@ end
     end
     githost["Github, Gitlab, BitBucket, etc."]
     githost2["\`Github, Gitlab, BitBucket, etc.\`"]
-    a["\`1.\`"]
-    b["\`- x\`"]
+    a["1."]
+    b["- x"]
       `;
 
     it('should render raw strings', () => {

cypress/integration/rendering/flowchart.spec.js

@@ -774,21 +774,6 @@ describe('Graph', () => {
       expect(svg).to.not.have.attr('style');
     });
   });
-  it('40: should add edge animation', () => {
-    renderGraph(
-      `
-      flowchart TD
-          A(["Start"]) L_A_B_0@--> B{"Decision"}
-          B --> C["Option A"] & D["Option B"]
-          style C stroke-width:4px,stroke-dasharray: 5
-          L_A_B_0@{ animation: slow } 
-          L_B_D_0@{ animation: fast }`,
-      { screenshot: false }
-    );
-    // Verify animation classes are applied to both edges
-    cy.get('path#L_A_B_0').should('have.class', 'edge-animation-slow');
-    cy.get('path#L_B_D_0').should('have.class', 'edge-animation-fast');
-  });
   it('58: handle styling with style expressions', () => {
     imgSnapshotTest(
       `
@@ -988,64 +973,4 @@ graph TD
       }
     );
   });
-
-  it('70: should render a subgraph with direction TD', () => {
-    imgSnapshotTest(
-      `
-      flowchart LR
-        subgraph A
-          direction TD
-          a --> b
-        end
-      `,
-      {
-        fontFamily: 'courier',
-      }
-    );
-  });
-  it('#5824: should be able to render string and markdown labels', () => {
-    imgSnapshotTest(
-      `
-flowchart TB
-    mermaid{"What is\nyourmermaid version?"} --> v10["<11"] --"\`<**1**1\`"--> fine["No bug"]
-    mermaid --> v11[">= v11"] -- ">= v11" --> broken["Affected by https://github.com/mermaid-js/mermaid/issues/5824"]
-    subgraph subgraph1["\`How to fix **fix**\`"]
-        broken --> B["B"]
-    end
-    githost["Github, Gitlab, BitBucket, etc."]
-    githost2["\`Github, Gitlab, BitBucket, etc.\`"]
-    a["1."]
-    b["- x"]
-    `,
-      {
-        flowchart: { htmlLabels: true },
-        securityLevel: 'loose',
-      }
-    );
-  });
-  it('69: should render subgraphs with adhoc list headings', () => {
-    imgSnapshotTest(
-      `
-    graph TB
-      subgraph "1. first"
-        a1-->a2
-      end
-      subgraph 2. second
-        b1-->b2
-      end
-      `,
-      { fontFamily: 'courier' }
-    );
-  });
-  it('70: should render subgraphs with markdown headings', () => {
-    imgSnapshotTest(
-      `
-    graph TB
-      subgraph "\`**strong**\`"
-        a1-->a2
-      end
-      `,
-      { fontFamily: 'courier' }
-    );
-  });
 });

cypress/integration/rendering/usecase.spec.ts

@@ -0,0 +1,425 @@
+import { imgSnapshotTest, renderGraph } from '../../helpers/util.ts';
+
+describe('Usecase diagram', () => {
+  it('should render a simple usecase diagram with actors and use cases', () => {
+    imgSnapshotTest(
+      `
+      usecase
+        actor User
+        actor Admin
+        User --> Login
+        Admin --> "Manage Users"
+        User --> "View Profile"
+      `
+    );
+  });
+
+  it('should render usecase diagram with quoted actor names', () => {
+    imgSnapshotTest(
+      `usecase
+        actor "Customer Service"
+        actor "System Administrator"
+        "Customer Service" --> "Handle Tickets"
+        "System Administrator" --> "Manage System"
+      `
+    );
+  });
+
+  it('should render usecase diagram with different arrow types', () => {
+    imgSnapshotTest(
+      `usecase
+        actor User
+        actor Admin
+        User --> Login
+        Admin <-- Logout
+        User -- "View Data"
+      `
+    );
+  });
+
+  it('should render usecase diagram with edge labels', () => {
+    imgSnapshotTest(
+      `usecase
+        actor Developer
+        actor Manager
+        Developer --important--> "Write Code"
+        Manager --review--> "Code Review"
+        Developer --urgent--> Manager
+      `
+    );
+  });
+
+  it('should render usecase diagram with node ID syntax', () => {
+    imgSnapshotTest(
+      `usecase
+        actor User
+        User --> a(Login)
+        User --> b("View Profile")
+        User --> c("Update Settings")
+      `
+    );
+  });
+
+  it('should render usecase diagram with comma-separated actors', () => {
+    imgSnapshotTest(
+      `usecase
+        actor "Customer Service", "Technical Support", "Sales Team"
+        actor SystemAdmin
+        "Customer Service" --> "Handle Tickets"
+        "Technical Support" --> "Resolve Issues"
+        "Sales Team" --> "Process Orders"
+        SystemAdmin --> "Manage System"
+      `
+    );
+  });
+
+  it('should render usecase diagram with actor metadata', () => {
+    imgSnapshotTest(
+      `usecase
+        actor User@{ "type" : "primary", "icon" : "user" }
+        actor Admin@{ "type" : "secondary", "icon" : "admin" }
+        actor System@{ "type" : "hollow", "icon" : "system" }
+        User --> Login
+        Admin --> "Manage Users"
+        System --> "Process Data"
+      `
+    );
+  });
+
+  it('should render usecase diagram with system boundaries (rect type)', () => {
+    imgSnapshotTest(
+      `usecase
+        actor Admin, User
+        systemBoundary "Authentication"
+          Login
+          Logout
+          "Reset Password"
+        end
+        "Authentication"@{ type: rect }
+        Admin --> Login
+        User --> Login
+        User --> "Reset Password"
+      `
+    );
+  });
+
+  it('should render usecase diagram with system boundaries (package type)', () => {
+    imgSnapshotTest(
+      `usecase
+        actor Admin, User
+        systemBoundary "Authentication"
+          Login
+          Logout
+          "Reset Password"
+        end
+        "Authentication"@{ type: package }
+        Admin --> Login
+        User --> Login
+        User --> "Reset Password"
+      `
+    );
+  });
+
+  it('should render complex usecase diagram with all features', () => {
+    imgSnapshotTest(
+      `usecase
+        actor "Customer Service"@{ "type" : "primary", "icon" : "user" }
+        actor "System Admin"@{ "type" : "secondary", "icon" : "admin" }
+        actor "Database"@{ "type" : "hollow", "icon" : "database" }
+
+        systemBoundary "Customer Support System"
+          "Handle Tickets"
+          "View Customer Info"
+        end
+        "Customer Support System"@{ type: package }
+
+        systemBoundary "Administration"
+          "User Management"
+          "System Config"
+        end
+
+        "Customer Service" --priority--> "Handle Tickets"
+        "Customer Service" --> "View Customer Info"
+        "System Admin" --manage--> "User Management"
+        "System Admin" --> "System Config"
+        "Database" <-- "Handle Tickets"
+        "Database" <-- "View Customer Info"
+        "Database" <-- "User Management"
+      `
+    );
+  });
+
+  it('should render usecase diagram with actor-to-actor relationships', () => {
+    imgSnapshotTest(
+      `usecase
+        actor Manager
+        actor Developer
+        actor Tester
+        
+        Manager --supervises--> Developer
+        Manager --coordinates--> Tester
+        Developer --collaborates--> Tester
+        
+        Developer --> "Write Code"
+        Tester --> "Test Code"
+        Manager --> "Review Progress"
+      `
+    );
+  });
+
+  it('should render usecase diagram with mixed relationship types', () => {
+    imgSnapshotTest(
+      `usecase
+        actor User
+        actor Admin
+        
+        User --> "Basic Login"
+        Admin --> "Advanced Login"
+        User --includes--> "View Profile"
+        Admin --extends--> "Manage Profiles"
+        
+        "Basic Login" <-- "Advanced Login"
+      `
+    );
+  });
+
+  it('should render usecase diagram with long labels and text wrapping', () => {
+    imgSnapshotTest(
+      `usecase
+        actor "Customer Service Representative"
+        actor "System Administrator with Extended Privileges"
+        
+        "Customer Service Representative" --Process--> "Handle Complex Customer Support Tickets"
+        "System Administrator with Extended Privileges" --> "Manage System Configuration and User Permissions"
+      `
+    );
+  });
+
+  it('should render usecase diagram with special characters in names', () => {
+    imgSnapshotTest(
+      `usecase
+        actor "User@Company.com"
+        actor "Admin (Level-1)"        
+        "User@Company.com" --> a("Login & Authenticate")
+        "Admin (Level-1)" --> b("Manage Users & Permissions")
+      `
+    );
+  });
+
+  it('should render usecase diagram when useMaxWidth is true (default)', () => {
+    renderGraph(
+      `usecase
+        actor User
+        actor Admin
+        User --> Login
+        Admin --> "Manage System"
+        User --> "View Profile"
+      `,
+      { usecase: { useMaxWidth: true } }
+    );
+    cy.get('svg').should((svg) => {
+      expect(svg).to.have.attr('width', '100%');
+      const style = svg.attr('style');
+      expect(style).to.match(/^max-width: [\d.]+px;$/);
+    });
+  });
+
+  it('should render usecase diagram when useMaxWidth is false', () => {
+    renderGraph(
+      `usecase
+        actor User
+        actor Admin
+        User --> Login
+        Admin --> "Manage System"
+      `,
+      { usecase: { useMaxWidth: false } }
+    );
+    cy.get('svg').should((svg) => {
+      const width = parseFloat(svg.attr('width'));
+      expect(width).to.be.greaterThan(200);
+      expect(svg).to.not.have.attr('style');
+    });
+  });
+
+  it('should render empty usecase diagram', () => {
+    imgSnapshotTest(`usecase`);
+  });
+
+  it('should render usecase diagram with only actors', () => {
+    imgSnapshotTest(
+      `usecase
+        actor User
+        actor Admin
+        actor Guest
+      `
+    );
+  });
+
+  it('should render usecase diagram with implicit use case creation', () => {
+    imgSnapshotTest(
+      `usecase
+        actor User
+        User --> Login
+        User --> Register
+        User --> "Forgot Password"
+      `
+    );
+  });
+
+  it('should render usecase diagram with nested system boundaries', () => {
+    imgSnapshotTest(
+      `usecase
+        actor User
+        actor Admin
+
+        systemBoundary "Main System"
+          Login
+          Logout
+          "Create User"
+          "Delete User"
+        end
+
+        User --> Login
+        User --> Logout
+        Admin --> "Create User"
+        Admin --> "Delete User"
+      `
+    );
+  });
+
+  it('should render usecase diagram with multiple edge labels on same relationship', () => {
+    imgSnapshotTest(
+      `usecase
+        actor Developer
+        actor Manager
+
+        Developer --"code review"--> Manager
+        Developer --"status update"--> Manager
+        Manager --"feedback"--> Developer
+        Manager --"approval"--> Developer
+      `
+    );
+  });
+
+  it('should render usecase diagram with various actor icon types', () => {
+    imgSnapshotTest(
+      `usecase
+        actor User@{ "icon": "user" }
+        actor Admin@{ "icon": "admin" }
+        actor Database@{ "icon": "database" }
+        actor API@{ "icon": "api" }
+        actor Mobile@{ "icon": "mobile" }
+        actor Web@{ "icon": "web" }
+
+        User --> "Access System"
+        Admin --> "Manage System"
+        Database --> "Store Data"
+        API --> "Provide Services"
+        Mobile --> "Mobile Access"
+        Web --> "Web Access"
+      `
+    );
+  });
+
+  it('should render usecase diagram with mixed arrow directions and labels', () => {
+    imgSnapshotTest(
+      `usecase
+        actor User
+        actor System
+        actor Admin
+
+        User --request--> System
+        System --response--> User
+        System <--monitor-- Admin
+        Admin --configure--> System
+        User -- "direct access" -- Admin
+      `
+    );
+  });
+
+  it('should render usecase diagram with boundary-less use cases', () => {
+    imgSnapshotTest(
+      `usecase
+        actor User
+        actor Admin
+
+        systemBoundary "Secure Area"
+          "Admin Panel"
+          "User Management"
+        end
+
+        User --> "Public Login"
+        User --> "Guest Access"
+        Admin --> "Public Login"
+        Admin --> "Admin Panel"
+        Admin --> "User Management"
+      `
+    );
+  });
+
+  it('should render usecase diagram with complex metadata combinations', () => {
+    imgSnapshotTest(
+      `usecase
+        actor "Primary User"@{ "type": "primary", "icon": "user", "fillColor": "lightblue" }
+        actor "Secondary User"@{ "type": "secondary", "icon": "client", "strokeColor": "red" }
+        actor "System Service"@{ "type": "hollow", "icon": "service", "strokeWidth": "3" }
+
+        "Primary User" --"high priority"--> a("Critical Process")
+        "Secondary User" --"low priority"--> b("Background Task")
+        "System Service" --"automated"--> c("System Maintenance")
+      `
+    );
+  });
+
+  it('should render usecase diagram with Unicode characters', () => {
+    imgSnapshotTest(
+      `usecase
+        actor "用户"@{ "icon": "user" }
+        actor "管理员"@{ "icon": "admin" }
+
+        "用户" --"登录"--> "系统访问"
+        "管理员" --"管理"--> "用户管理"
+        "用户" --> "数据查看"
+      `
+    );
+  });
+
+  it('should render large usecase diagram with many elements', () => {
+    imgSnapshotTest(
+      `usecase
+        actor User1, User2, User3, User4
+        actor Admin1, Admin2
+        actor System1@{ "icon": "system" }
+        actor System2@{ "icon": "database" }
+
+        systemBoundary "Module A"
+          "Feature A1"
+          "Feature A2"
+          "Admin A1"
+        end
+        "Module A"@{ type: package }
+
+        systemBoundary "Module B"
+          "Feature B1"
+          "Feature B2"
+          "Admin B1"
+        end
+
+        User1 --> "Feature A1"
+        User2 --> "Feature A2"
+        Admin1 --> "Admin A1"
+        User3 --> "Feature B1"
+        User4 --> "Feature B2"
+        Admin2 --> "Admin B1"
+
+        System1 <-- "Feature A1"
+        System1 <-- "Feature B1"
+        System2 <-- "Admin A1"
+        System2 <-- "Admin B1"
+
+        User1 --"collaborates"--> User2
+        Admin1 --"supervises"--> Admin2
+      `
+    );
+  });
+});

cypress/platform/yari.html

@@ -603,10 +603,6 @@
       </div>
       <div class="test">
         <pre class="mermaid">
-          ---
-            config:
-              theme: dark
-          ---
           classDiagram
             test ()--() test2
         </pre>

demos/classchart.html

@@ -184,7 +184,6 @@
       }
       Admin --> Report : generates
     </pre>
-    <hr />
     <pre class="mermaid">
     classDiagram
       namespace Company.Project.Module {
@@ -241,20 +240,6 @@
       Bike --> Square : "Logo Shape"
 
     </pre>
-    <hr />
-    <pre class="mermaid">
-      classDiagram
-        note "This is a outer note"
-        note for Class1 "This is a outer note for Class1"
-        namespace ns {
-          note "This is a inner note"
-          note for Class1 "This is a inner note for Class1"
-          class Class1
-          class Class2
-        }
-    </pre>
-    <hr />
-
     <script type="module">
       import mermaid from './mermaid.esm.mjs';
       mermaid.initialize({

demos/usecase.html

@@ -0,0 +1,234 @@
+<html>
+  <head>
+    <link href="https://fonts.googleapis.com/css?family=Montserrat&display=swap" rel="stylesheet" />
+    <link href="https://unpkg.com/tailwindcss@^1.0/dist/tailwind.min.css" rel="stylesheet" />
+    <link
+      rel="stylesheet"
+      href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css"
+    />
+    <link
+      href="https://cdn.jsdelivr.net/npm/@mdi/font@6.9.96/css/materialdesignicons.min.css"
+      rel="stylesheet"
+    />
+    <link
+      href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.5.1/css/all.min.css"
+      rel="stylesheet"
+    />
+    <link
+      href="https://fonts.googleapis.com/css?family=Noto+Sans+SC&display=swap"
+      rel="stylesheet"
+    />
+    <link rel="preconnect" href="https://fonts.googleapis.com" />
+    <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin />
+    <link
+      href="https://fonts.googleapis.com/css2?family=Kalam:wght@300;400;700&display=swap"
+      rel="stylesheet"
+    />
+    <link
+      href="https://fonts.googleapis.com/css2?family=Caveat:wght@400..700&family=Kalam:wght@300;400;700&family=Rubik+Mono+One&display=swap"
+      rel="stylesheet"
+    />
+    <link
+      href="https://fonts.googleapis.com/css2?family=Kalam:wght@300;400;700&family=Rubik+Mono+One&display=swap"
+      rel="stylesheet"
+    />
+    <link
+      href="https://fonts.googleapis.com/css2?family=Recursive:wght@300..1000&display=swap"
+      rel="stylesheet"
+    />
+
+    <style>
+      .recursive-500 {
+        font-family: 'Recursive', serif;
+        font-optical-sizing: auto;
+        font-weight: 500;
+        font-style: normal;
+        font-variation-settings:
+          'slnt' 0,
+          'CASL' 0,
+          'CRSV' 0.5,
+          'MONO' 0;
+      }
+      body {
+        /* background: rgb(221, 208, 208); */
+        /* background: #333; */
+        /* font-family: 'Arial'; */
+        font-family: 'Recursive', serif;
+        font-optical-sizing: auto;
+        font-weight: 500;
+        font-style: normal;
+        font-variation-settings:
+          'slnt' 0,
+          'CASL' 0,
+          'CRSV' 0.5,
+          'MONO' 0;
+        /* color: white; */
+        /* font-size: 18px !important; */
+      }
+      .gridify.tiny {
+        background-image:
+          linear-gradient(transparent 11px, rgba(220, 220, 200, 0.8) 12px, transparent 12px),
+          linear-gradient(90deg, transparent 11px, rgba(220, 220, 200, 0.8) 12px, transparent 12px);
+        background-size:
+          100% 12px,
+          12px 100%;
+      }
+
+      .gridify.dots {
+        background-image: radial-gradient(
+          circle at center,
+          rgba(220, 220, 200, 0.8) 1px,
+          transparent 1px
+        );
+        background-size: 24px 24px;
+      }
+
+      h1 {
+        color: grey;
+      }
+
+      .mermaid2 {
+        display: none;
+      }
+
+      .mermaid svg {
+        font-size: 16px !important;
+        font-family: 'Recursive', serif;
+        font-optical-sizing: auto;
+        font-weight: 500;
+        font-style: normal;
+        font-variation-settings:
+          'slnt' 0,
+          'CASL' 0,
+          'CRSV' 0.5,
+          'MONO' 0;
+      }
+
+      pre {
+        width: 100%;
+        /*box-shadow: 4px 4px 0px 0px #0000000F;*/
+      }
+    </style>
+  </head>
+
+  <body class="gridify dots">
+    <p class="mb-20">Test Diagram</p>
+    <div class="w-full h-64">
+      <pre id="diagram4" class="mermaid">
+usecase
+direction LR
+        actor User1, User2, User3, User4
+        actor Admin1, Admin2
+        actor System1@{ "icon": "bell" }
+        actor System2@{ "icon": "database" }
+
+        systemBoundary "Module A"
+          "Feature A1"
+          "Feature A2"
+          "Admin A1"
+
+        end
+        "Module A"@{ type: package }
+
+        systemBoundary "Module B"
+          "Feature B1"
+          "Feature B2"
+          "Admin B1"
+        end
+
+        User1 --important--> "Feature A1"
+        User2 --> "Feature A2"
+        Admin1 --> "Admin A1"
+        User3 --> "Feature B1"
+        User4 --> "Feature B2"
+        Admin2 --> "Admin B1"
+
+        System1 <-- "Feature A1"
+        System1 <-- "Feature B1"
+        System2 <-- "Admin A1"
+        System2 <-- "Admin B1"
+
+        User1 --"collaborates"--> User2
+        Admin1 --"supervises"--> Admin2
+
+    </pre
+      >
+    </div>
+
+    <script type="module">
+      import mermaid from './mermaid.esm.mjs';
+      import layouts from './mermaid-layout-elk.esm.mjs';
+
+      const staticBellIconPack = {
+        prefix: 'fa6-regular',
+        icons: {
+          bell: {
+            body: '<path fill="currentColor" d="M224 0c-17.7 0-32 14.3-32 32v19.2C119 66 64 130.6 64 208v25.4c0 45.4-15.5 89.5-43.8 124.9L5.3 377c-5.8 7.2-6.9 17.1-2.9 25.4S14.8 416 24 416h400c9.2 0 17.6-5.3 21.6-13.6s2.9-18.2-2.9-25.4l-14.9-18.6c-28.3-35.5-43.8-79.6-43.8-125V208c0-77.4-55-142-128-156.8V32c0-17.7-14.3-32-32-32m0 96c61.9 0 112 50.1 112 112v25.4c0 47.9 13.9 94.6 39.7 134.6H72.3c25.8-40 39.7-86.7 39.7-134.6V208c0-61.9 50.1-112 112-112m64 352H160c0 17 6.7 33.3 18.7 45.3S207 512 224 512s33.3-6.7 45.3-18.7S288 465 288 448"/>',
+            width: 448,
+          },
+        },
+        width: 512,
+        height: 512,
+      };
+
+      mermaid.registerIconPacks([
+        {
+          name: 'logos',
+          loader: () =>
+            fetch('https://unpkg.com/@iconify-json/logos@1/icons.json').then((res) => res.json()),
+        },
+        {
+          name: 'fa',
+          loader: () =>
+            fetch('https://unpkg.com/@iconify-json/fa6-solid/icons.json').then((res) => res.json()),
+        },
+      ]);
+      mermaid.registerLayoutLoaders(layouts);
+      mermaid.parseError = function (err, hash) {
+        console.error('Mermaid error: ', err);
+      };
+      window.callback = function () {
+        alert('A callback was triggered');
+      };
+      function callback() {
+        alert('It worked');
+      }
+      await mermaid.initialize({
+        startOnLoad: false,
+        theme: 'default',
+        // theme: 'forest',
+        // handDrawnSeed: 12,
+        // 'elk.nodePlacement.strategy': 'NETWORK_SIMPLEX',
+        layout: 'dagre',
+        // layout: 'elk',
+        // layout: 'fixed',
+        // htmlLabels: false,
+        flowchart: { titleTopMargin: 10 },
+
+        // fontFamily: 'Caveat',
+        // fontFamily: 'Kalam',
+        // fontFamily: 'courier',
+        fontFamily: 'Recursive',
+        sequence: {
+          actorFontFamily: 'courier',
+          noteFontFamily: 'courier',
+          messageFontFamily: 'courier',
+        },
+        kanban: {
+          htmlLabels: false,
+        },
+        fontSize: 16,
+        logLevel: 0,
+        securityLevel: 'loose',
+        callback,
+      });
+      // setTimeout(() => {
+      mermaid.init(undefined, document.querySelectorAll('.mermaid'));
+      // }, 1000);
+      mermaid.parseError = function (err, hash) {
+        console.error('In parse error:');
+        console.error(err);
+      };
+    </script>
+  </body>
+</html>

docs/config/setup/defaultConfig/variables/configKeys.md

@@ -12,4 +12,4 @@
 
 > `const` **configKeys**: `Set`<`string`>
 
-Defined in: [packages/mermaid/src/defaultConfig.ts:292](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/defaultConfig.ts#L292)
+Defined in: [packages/mermaid/src/defaultConfig.ts:295](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/defaultConfig.ts#L295)

docs/config/setup/mermaid/interfaces/MermaidConfig.md

@@ -105,7 +105,7 @@ You can set this attribute to base the seed on a static string.
 
 > `optional` **dompurifyConfig**: `Config`
 
-Defined in: [packages/mermaid/src/config.type.ts:213](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/config.type.ts#L213)
+Defined in: [packages/mermaid/src/config.type.ts:214](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/config.type.ts#L214)
 
 ---
 
@@ -179,7 +179,7 @@ See <https://developer.mozilla.org/en-US/docs/Web/CSS/font-family>
 
 > `optional` **fontSize**: `number`
 
-Defined in: [packages/mermaid/src/config.type.ts:215](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/config.type.ts#L215)
+Defined in: [packages/mermaid/src/config.type.ts:216](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/config.type.ts#L216)
 
 ---
 
@@ -292,7 +292,7 @@ Defines which main look to use for the diagram.
 
 > `optional` **markdownAutoWrap**: `boolean`
 
-Defined in: [packages/mermaid/src/config.type.ts:216](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/config.type.ts#L216)
+Defined in: [packages/mermaid/src/config.type.ts:217](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/config.type.ts#L217)
 
 ---
 
@@ -424,7 +424,7 @@ Defined in: [packages/mermaid/src/config.type.ts:198](https://github.com/mermaid
 
 > `optional` **suppressErrorRendering**: `boolean`
 
-Defined in: [packages/mermaid/src/config.type.ts:222](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/config.type.ts#L222)
+Defined in: [packages/mermaid/src/config.type.ts:223](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/config.type.ts#L223)
 
 Suppresses inserting 'Syntax error' diagram in the DOM.
 This is useful when you want to control how to handle syntax errors in your application.
@@ -466,11 +466,19 @@ Defined in: [packages/mermaid/src/config.type.ts:196](https://github.com/mermaid
 
 ---
 
+### usecase?
+
+> `optional` **usecase**: `UsecaseDiagramConfig`
+
+Defined in: [packages/mermaid/src/config.type.ts:213](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/config.type.ts#L213)
+
+---
+
 ### wrap?
 
 > `optional` **wrap**: `boolean`
 
-Defined in: [packages/mermaid/src/config.type.ts:214](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/config.type.ts#L214)
+Defined in: [packages/mermaid/src/config.type.ts:215](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/config.type.ts#L215)
 
 ---
 

docs/config/setup/mermaid/interfaces/ParseOptions.md

@@ -10,7 +10,7 @@
 
 # Interface: ParseOptions
 
-Defined in: [packages/mermaid/src/types.ts:89](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L89)
+Defined in: [packages/mermaid/src/types.ts:88](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L88)
 
 ## Properties
 
@@ -18,7 +18,7 @@ Defined in: [packages/mermaid/src/types.ts:89](https://github.com/mermaid-js/mer
 
 > `optional` **suppressErrors**: `boolean`
 
-Defined in: [packages/mermaid/src/types.ts:94](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L94)
+Defined in: [packages/mermaid/src/types.ts:93](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L93)
 
 If `true`, parse will return `false` instead of throwing error when the diagram is invalid.
 The `parseError` function will not be called.

docs/config/setup/mermaid/interfaces/ParseResult.md

@@ -10,7 +10,7 @@
 
 # Interface: ParseResult
 
-Defined in: [packages/mermaid/src/types.ts:97](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L97)
+Defined in: [packages/mermaid/src/types.ts:96](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L96)
 
 ## Properties
 
@@ -18,7 +18,7 @@ Defined in: [packages/mermaid/src/types.ts:97](https://github.com/mermaid-js/mer
 
 > **config**: [`MermaidConfig`](MermaidConfig.md)
 
-Defined in: [packages/mermaid/src/types.ts:105](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L105)
+Defined in: [packages/mermaid/src/types.ts:104](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L104)
 
 The config passed as YAML frontmatter or directives
 
@@ -28,6 +28,6 @@ The config passed as YAML frontmatter or directives
 
 > **diagramType**: `string`
 
-Defined in: [packages/mermaid/src/types.ts:101](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L101)
+Defined in: [packages/mermaid/src/types.ts:100](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L100)
 
 The diagram type, e.g. 'flowchart', 'sequence', etc.

docs/config/setup/mermaid/interfaces/RenderResult.md

@@ -10,7 +10,7 @@
 
 # Interface: RenderResult
 
-Defined in: [packages/mermaid/src/types.ts:115](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L115)
+Defined in: [packages/mermaid/src/types.ts:114](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L114)
 
 ## Properties
 
@@ -18,7 +18,7 @@ Defined in: [packages/mermaid/src/types.ts:115](https://github.com/mermaid-js/me
 
 > `optional` **bindFunctions**: (`element`) => `void`
 
-Defined in: [packages/mermaid/src/types.ts:133](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L133)
+Defined in: [packages/mermaid/src/types.ts:132](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L132)
 
 Bind function to be called after the svg has been inserted into the DOM.
 This is necessary for adding event listeners to the elements in the svg.
@@ -45,7 +45,7 @@ bindFunctions?.(div); // To call bindFunctions only if it's present.
 
 > **diagramType**: `string`
 
-Defined in: [packages/mermaid/src/types.ts:123](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L123)
+Defined in: [packages/mermaid/src/types.ts:122](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L122)
 
 The diagram type, e.g. 'flowchart', 'sequence', etc.
 
@@ -55,6 +55,6 @@ The diagram type, e.g. 'flowchart', 'sequence', etc.
 
 > **svg**: `string`
 
-Defined in: [packages/mermaid/src/types.ts:119](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L119)
+Defined in: [packages/mermaid/src/types.ts:118](https://github.com/mermaid-js/mermaid/blob/master/packages/mermaid/src/types.ts#L118)
 
 The svg code for the rendered graph.

docs/ecosystem/integrations-community.md

@@ -57,8 +57,6 @@ To add an integration to this list, see the [Integrations - create page](./integ
   - [GitHub Writer](https://github.com/ckeditor/github-writer)
   - [SVG diagram generator](https://github.com/SimonKenyonShepard/mermaidjs-github-svg-generator)
 - [GitLab](https://docs.gitlab.com/ee/user/markdown.html#diagrams-and-flowcharts) ✅
-- [GNU Octave](https://octave.org/) ✅
-  - [octave_mermaid_js](https://github.com/CNOCTAVE/octave_mermaid_js) ✅
 - [Mermaid Plugin for JetBrains IDEs](https://plugins.jetbrains.com/plugin/20146-mermaid)
 - [MonsterWriter](https://www.monsterwriter.com/) ✅
 - [Joplin](https://joplinapp.org) ✅
@@ -274,7 +272,6 @@ Communication tools and platforms
   - [reveal.js-mermaid-plugin](https://github.com/ludwick/reveal.js-mermaid-plugin)
 - [Reveal CK](https://github.com/jedcn/reveal-ck)
   - [reveal-ck-mermaid-plugin](https://github.com/tmtm/reveal-ck-mermaid-plugin)
-- [speccharts: Turn your test suites into specification diagrams](https://github.com/arnaudrenaud/speccharts)
 - [Vitepress Plugin](https://github.com/sametcn99/vitepress-mermaid-renderer)
 
 <!--- cspell:ignore Blazorade HueHive --->

docs/ecosystem/mermaid-chart.md

@@ -47,7 +47,7 @@ Try the Ultimate AI, Mermaid, and Visual Diagramming Suite by creating an accoun
 
 ## Plans
 
-- **Free** - A free plan that includes six diagrams.
+- **Free** - A free plan that includes three diagrams.
 
 - **Pro** - A paid plan that includes unlimited diagrams, access to the collaboration feature, and more.
 

docs/syntax/classDiagram.md

@@ -21,7 +21,7 @@ title: Animal example
 classDiagram
     note "From Duck till Zebra"
     Animal <|-- Duck
-    note for Duck "can fly<br>can swim<br>can dive<br>can help in debugging"
+    note for Duck "can fly\ncan swim\ncan dive\ncan help in debugging"
     Animal <|-- Fish
     Animal <|-- Zebra
     Animal : +int age
@@ -50,7 +50,7 @@ title: Animal example
 classDiagram
     note "From Duck till Zebra"
     Animal <|-- Duck
-    note for Duck "can fly<br>can swim<br>can dive<br>can help in debugging"
+    note for Duck "can fly\ncan swim\ncan dive\ncan help in debugging"
     Animal <|-- Fish
     Animal <|-- Zebra
     Animal : +int age

docs/syntax/flowchart.md

@@ -344,6 +344,7 @@ Below is a comprehensive list of the newly introduced shapes and their correspon
 | Display                           | Curved Trapezoid       | `curv-trap`    | Represents a display           | `curved-trapezoid`, `display`                                    |
 | Divided Process                   | Divided Rectangle      | `div-rect`     | Divided process shape          | `div-proc`, `divided-process`, `divided-rectangle`               |
 | Document                          | Document               | `doc`          | Represents a document          | `doc`, `document`                                                |
+| Ellipse                           | Ellipse                | `ellipse`      | Ellipse shape                  | `oval`                                                           |
 | Event                             | Rounded Rectangle      | `rounded`      | Represents an event            | `event`                                                          |
 | Extract                           | Triangle               | `tri`          | Extraction process             | `extract`, `triangle`                                            |
 | Fork/Join                         | Filled Rectangle       | `fork`         | Fork or join in process flow   | `join`                                                           |

packages/examples/src/examples/usecase.ts

@@ -0,0 +1,51 @@
+import type { DiagramMetadata } from '../types.js';
+
+export default {
+  id: 'usecase',
+  name: 'Use Case Diagram',
+  description: 'Visualize system functionality and user interactions',
+  examples: [
+    {
+      title: 'Basic Use Case',
+      isDefault: true,
+      code: `usecase
+actor User
+actor Admin
+User --> (Login)
+User --> (View Profile)
+Admin --> (Manage Users)
+Admin --> (View Reports)`,
+    },
+    {
+      title: 'System Boundary',
+      code: `usecase
+actor Customer
+actor Support
+
+SystemBoundary@{ type: rect } "E-commerce System" {
+  Customer --> (Browse Products)
+  Customer --> (Place Order)
+  Customer --> (Track Order)
+}
+
+SystemBoundary@{ type: package } "Admin Panel" {
+  Support --> (Process Orders)
+  Support --> (Handle Returns)
+}`,
+    },
+    {
+      title: 'Actor Relationships',
+      code: `usecase
+actor Developer1
+actor Developer2
+actor Manager
+
+Developer1 --> (Write Code)
+Developer2 --> (Review Code)
+Manager --> (Approve Release)
+
+Developer1 --> Developer2
+Manager --> Developer1`,
+    },
+  ],
+} satisfies DiagramMetadata;

packages/examples/src/index.ts

@@ -21,6 +21,7 @@ import quadrantChart from './examples/quadrant-chart.js';
 import packetDiagram from './examples/packet.js';
 import blockDiagram from './examples/block.js';
 import treemapDiagram from './examples/treemap.js';
+import usecaseDiagram from './examples/usecase.js';
 
 export const diagramData: DiagramMetadata[] = [
   flowChart,
@@ -45,4 +46,5 @@ export const diagramData: DiagramMetadata[] = [
   packetDiagram,
   blockDiagram,
   treemapDiagram,
+  usecaseDiagram,
 ];

packages/mermaid-layout-elk/package.json

@@ -18,9 +18,7 @@
     "elk",
     "mermaid"
   ],
-  "scripts": {
-    "clean": "rimraf dist"
-  },
+  "scripts": {},
   "repository": {
     "type": "git",
     "url": "https://github.com/mermaid-js/mermaid"

packages/mermaid-layout-tidy-tree/package.json

@@ -19,9 +19,7 @@
     "mermaid",
     "layout"
   ],
-  "scripts": {
-    "clean": "rimraf dist"
-  },
+  "scripts": {},
   "repository": {
     "type": "git",
     "url": "https://github.com/mermaid-js/mermaid"

packages/mermaid/CHANGELOG.md

@@ -1,30 +1,5 @@
 # mermaid
 
-## 11.12.1
-
-### Patch Changes
-
-- [#7107](https://github.com/mermaid-js/mermaid/pull/7107) [`cbf8946`](https://github.com/mermaid-js/mermaid/commit/cbf89462acecac7a06f19843e8d48cb137df0753) Thanks [@shubhamparikh2704](https://github.com/shubhamparikh2704)! - fix: Updated the dependency dagre-d3-es to 7.0.13 to fix GHSA-cc8p-78qf-8p7q
-
-## 11.12.0
-
-### Minor Changes
-
-- [#6921](https://github.com/mermaid-js/mermaid/pull/6921) [`764b315`](https://github.com/mermaid-js/mermaid/commit/764b315dc16d0359add7c6b8e3ef7592e9bdc09c) Thanks [@quilicicf](https://github.com/quilicicf)! - feat: Add IDs in architecture diagrams
-
-### Patch Changes
-
-- [#6950](https://github.com/mermaid-js/mermaid/pull/6950) [`a957908`](https://github.com/mermaid-js/mermaid/commit/a9579083bfba367a4f4678547ec37ed7b61b9f5b) Thanks [@shubhamparikh2704](https://github.com/shubhamparikh2704)! - chore: Fix mindmap rendering in docs and apply tidytree layout
-
-- [#6826](https://github.com/mermaid-js/mermaid/pull/6826) [`1d36810`](https://github.com/mermaid-js/mermaid/commit/1d3681053b9168354e48e5763023b6305cd1ca72) Thanks [@darshanr0107](https://github.com/darshanr0107)! - fix: Ensure edge label color is applied when using classDef with edge IDs
-
-- [#6945](https://github.com/mermaid-js/mermaid/pull/6945) [`d318f1a`](https://github.com/mermaid-js/mermaid/commit/d318f1a13cd7429334a29c70e449074ec1cb9f68) Thanks [@darshanr0107](https://github.com/darshanr0107)! - fix: Resolve gantt chart crash due to invalid array length
-
-- [#6918](https://github.com/mermaid-js/mermaid/pull/6918) [`cfe9238`](https://github.com/mermaid-js/mermaid/commit/cfe9238882cbe95416db1feea3112456a71b6aaf) Thanks [@shubhamparikh2704](https://github.com/shubhamparikh2704)! - chore: revert marked dependency from ^15.0.7 to ^16.0.0
-  - Reverted marked package version to ^16.0.0 for better compatibility
-  - This is a dependency update that maintains API compatibility
-  - All tests pass with the updated version
-
 ## 11.11.0
 
 ### Minor Changes

packages/mermaid/package.json

@@ -1,6 +1,6 @@
 {
   "name": "mermaid",
-  "version": "11.12.1",
+  "version": "11.11.0",
   "description": "Markdown-ish syntax for generating flowcharts, mindmaps, sequence diagrams, class diagrams, gantt charts, git graphs and more.",
   "type": "module",
   "module": "./dist/mermaid.core.mjs",
@@ -47,7 +47,7 @@
     "docs:verify-version": "tsx scripts/update-release-version.mts --verify",
     "types:build-config": "tsx scripts/create-types-from-json-schema.mts",
     "types:verify-config": "tsx scripts/create-types-from-json-schema.mts --verify",
-    "checkCircle": "npx madge --circular ./src",
+    "checkCircle": "npx madge --circular ./src --exclude '.*generated.*'",
     "prepublishOnly": "pnpm docs:verify-version"
   },
   "repository": {
@@ -76,7 +76,7 @@
     "cytoscape-fcose": "^2.2.0",
     "d3": "^7.9.0",
     "d3-sankey": "^0.12.3",
-    "dagre-d3-es": "7.0.13",
+    "dagre-d3-es": "7.0.11",
     "dayjs": "^1.11.18",
     "dompurify": "^3.2.5",
     "katex": "^0.16.22",

packages/mermaid/scripts/docs.spec.ts

@@ -189,6 +189,7 @@ This Markdown should be kept.
         | Display                           | Curved Trapezoid       | \`curv-trap\`    | Represents a display           | \`curved-trapezoid\`, \`display\`                                    |
         | Divided Process                   | Divided Rectangle      | \`div-rect\`     | Divided process shape          | \`div-proc\`, \`divided-process\`, \`divided-rectangle\`               |
         | Document                          | Document               | \`doc\`          | Represents a document          | \`doc\`, \`document\`                                                |
+        | Ellipse                           | Ellipse                | \`ellipse\`      | Ellipse shape                  | \`oval\`                                                           |
         | Event                             | Rounded Rectangle      | \`rounded\`      | Represents an event            | \`event\`                                                          |
         | Extract                           | Triangle               | \`tri\`          | Extraction process             | \`extract\`, \`triangle\`                                            |
         | Fork/Join                         | Filled Rectangle       | \`fork\`         | Fork or join in process flow   | \`join\`                                                           |

packages/mermaid/src/config.type.ts

@@ -210,6 +210,7 @@ export interface MermaidConfig {
   packet?: PacketDiagramConfig;
   block?: BlockDiagramConfig;
   radar?: RadarDiagramConfig;
+  usecase?: UsecaseDiagramConfig;
   dompurifyConfig?: DOMPurifyConfiguration;
   wrap?: boolean;
   fontSize?: number;
@@ -1623,6 +1624,50 @@ export interface RadarDiagramConfig extends BaseDiagramConfig {
    */
   curveTension?: number;
 }
+/**
+ * The object containing configurations specific for usecase diagrams.
+ *
+ * This interface was referenced by `MermaidConfig`'s JSON-Schema
+ * via the `definition` "UsecaseDiagramConfig".
+ */
+export interface UsecaseDiagramConfig extends BaseDiagramConfig {
+  /**
+   * Font size for actor labels
+   */
+  actorFontSize?: number;
+  /**
+   * Font family for actor labels
+   */
+  actorFontFamily?: string;
+  /**
+   * Font weight for actor labels
+   */
+  actorFontWeight?: string;
+  /**
+   * Font size for usecase labels
+   */
+  usecaseFontSize?: number;
+  /**
+   * Font family for usecase labels
+   */
+  usecaseFontFamily?: string;
+  /**
+   * Font weight for usecase labels
+   */
+  usecaseFontWeight?: string;
+  /**
+   * Margin around actors
+   */
+  actorMargin?: number;
+  /**
+   * Margin around use cases
+   */
+  usecaseMargin?: number;
+  /**
+   * Padding around the entire diagram
+   */
+  diagramPadding?: number;
+}
 /**
  * This interface was referenced by `MermaidConfig`'s JSON-Schema
  * via the `definition` "FontConfig".

packages/mermaid/src/defaultConfig.ts

@@ -264,6 +264,9 @@ const config: RequiredDeep<MermaidConfig> = {
   radar: {
     ...defaultConfigJson.radar,
   },
+  usecase: {
+    ...defaultConfigJson.usecase,
+  },
   treemap: {
     useMaxWidth: true,
     padding: 10,

packages/mermaid/src/diagram-api/diagram-orchestration.ts

@@ -28,6 +28,7 @@ import architecture from '../diagrams/architecture/architectureDetector.js';
 import { registerLazyLoadedDiagrams } from './detectType.js';
 import { registerDiagram } from './diagramAPI.js';
 import { treemap } from '../diagrams/treemap/detector.js';
+import { usecase } from '../diagrams/usecase/usecaseDetector.js';
 import '../type.d.ts';
 
 let hasLoadedDiagrams = false;
@@ -72,7 +73,7 @@ export const addDiagrams = () => {
     }
   );
 
-  if (injected.includeLargeFeatures) {
+  if (includeLargeFeatures) {
     registerLazyLoadedDiagrams(flowchartElk, mindmap, architecture);
   }
 
@@ -101,6 +102,7 @@ export const addDiagrams = () => {
     xychart,
     block,
     radar,
-    treemap
+    treemap,
+    usecase
   );
 };

packages/mermaid/src/diagrams/class/classDb.ts

@@ -17,7 +17,6 @@ import type {
   ClassRelation,
   ClassNode,
   ClassNote,
-  ClassNoteMap,
   ClassMap,
   NamespaceMap,
   NamespaceNode,
@@ -34,16 +33,15 @@ const sanitizeText = (txt: string) => common.sanitizeText(txt, getConfig());
 
 export class ClassDB implements DiagramDB {
   private relations: ClassRelation[] = [];
-  private classes: ClassMap = new Map<string, ClassNode>();
+  private classes = new Map<string, ClassNode>();
   private readonly styleClasses = new Map<string, StyleClass>();
-  private notes: ClassNoteMap = new Map<string, ClassNote>();
+  private notes: ClassNote[] = [];
   private interfaces: Interface[] = [];
   // private static classCounter = 0;
   private namespaces = new Map<string, NamespaceNode>();
   private namespaceCounter = 0;
 
-  // eslint-disable-next-line @typescript-eslint/no-unsafe-function-type
-  private functions: Function[] = [];
+  private functions: any[] = [];
 
   constructor() {
     this.functions.push(this.setupToolTips.bind(this));
@@ -126,7 +124,7 @@ export class ClassDB implements DiagramDB {
       annotations: [],
       styles: [],
       domId: MERMAID_DOM_ID_PREFIX + name + '-' + classCounter,
-    });
+    } as ClassNode);
 
     classCounter++;
   }
@@ -157,12 +155,12 @@ export class ClassDB implements DiagramDB {
 
   public clear() {
     this.relations = [];
-    this.classes = new Map<string, ClassNode>();
-    this.notes = new Map<string, ClassNote>();
+    this.classes = new Map();
+    this.notes = [];
     this.interfaces = [];
     this.functions = [];
     this.functions.push(this.setupToolTips.bind(this));
-    this.namespaces = new Map<string, NamespaceNode>();
+    this.namespaces = new Map();
     this.namespaceCounter = 0;
     this.direction = 'TB';
     commonClear();
@@ -180,12 +178,7 @@ export class ClassDB implements DiagramDB {
     return this.relations;
   }
 
-  public getNote(id: string | number): ClassNote {
-    const key = typeof id === 'number' ? `note${id}` : id;
-    return this.notes.get(key)!;
-  }
-
-  public getNotes(): ClassNoteMap {
+  public getNotes() {
     return this.notes;
   }
 
@@ -286,19 +279,16 @@ export class ClassDB implements DiagramDB {
     }
   }
 
-  public addNote(text: string, className: string): string {
-    const index = this.notes.size;
+  public addNote(text: string, className: string) {
     const note = {
-      id: `note${index}`,
+      id: `note${this.notes.length}`,
       class: className,
       text: text,
-      index: index,
     };
-    this.notes.set(note.id, note);
-    return note.id;
+    this.notes.push(note);
   }
 
-  public cleanupLabel(label: string): string {
+  public cleanupLabel(label: string) {
     if (label.startsWith(':')) {
       label = label.substring(1);
     }
@@ -364,7 +354,7 @@ export class ClassDB implements DiagramDB {
     });
   }
 
-  public getTooltip(id: string, namespace?: string): string | undefined {
+  public getTooltip(id: string, namespace?: string) {
     if (namespace && this.namespaces.has(namespace)) {
       return this.namespaces.get(namespace)!.classes.get(id)!.tooltip;
     }
@@ -544,11 +534,10 @@ export class ClassDB implements DiagramDB {
 
     this.namespaces.set(id, {
       id: id,
-      classes: new Map<string, ClassNode>(),
-      notes: new Map<string, ClassNote>(),
-      children: new Map<string, NamespaceNode>(),
+      classes: new Map(),
+      children: {},
       domId: MERMAID_DOM_ID_PREFIX + id + '-' + this.namespaceCounter,
-    });
+    } as NamespaceNode);
 
     this.namespaceCounter++;
   }
@@ -566,23 +555,16 @@ export class ClassDB implements DiagramDB {
    *
    * @param id - ID of the namespace to add
    * @param classNames - IDs of the class to add
-   * @param noteNames - IDs of the notes to add
    * @public
    */
-  public addClassesToNamespace(id: string, classNames: string[], noteNames: string[]) {
+  public addClassesToNamespace(id: string, classNames: string[]) {
     if (!this.namespaces.has(id)) {
       return;
     }
     for (const name of classNames) {
       const { className } = this.splitClassNameAndType(name);
-      const classNode = this.getClass(className);
-      classNode.parent = id;
-      this.namespaces.get(id)!.classes.set(className, classNode);
-    }
-    for (const noteName of noteNames) {
-      const noteNode = this.getNote(noteName);
-      noteNode.parent = id;
-      this.namespaces.get(id)!.notes.set(noteName, noteNode);
+      this.classes.get(className)!.parent = id;
+      this.namespaces.get(id)!.classes.set(className, this.classes.get(className)!);
     }
   }
 
@@ -635,32 +617,36 @@ export class ClassDB implements DiagramDB {
     const edges: Edge[] = [];
     const config = getConfig();
 
-    for (const namespace of this.namespaces.values()) {
-      const node: Node = {
-        id: namespace.id,
-        label: namespace.id,
-        isGroup: true,
-        padding: config.class!.padding ?? 16,
-        // parent node must be one of [rect, roundedWithTitle, noteGroup, divider]
-        shape: 'rect',
-        cssStyles: [],
-        look: config.look,
-      };
-      nodes.push(node);
+    for (const namespaceKey of this.namespaces.keys()) {
+      const namespace = this.namespaces.get(namespaceKey);
+      if (namespace) {
+        const node: Node = {
+          id: namespace.id,
+          label: namespace.id,
+          isGroup: true,
+          padding: config.class!.padding ?? 16,
+          // parent node must be one of [rect, roundedWithTitle, noteGroup, divider]
+          shape: 'rect',
+          cssStyles: ['fill: none', 'stroke: black'],
+          look: config.look,
+        };
+        nodes.push(node);
+      }
     }
 
-    for (const classNode of this.classes.values()) {
-      const node: Node = {
-        ...classNode,
-        type: undefined,
-        isGroup: false,
-        parentId: classNode.parent,
-        look: config.look,
-      };
-      nodes.push(node);
+    for (const classKey of this.classes.keys()) {
+      const classNode = this.classes.get(classKey);
+      if (classNode) {
+        const node = classNode as unknown as Node;
+        node.parentId = classNode.parent;
+        node.look = config.look;
+        nodes.push(node);
+      }
     }
 
-    for (const note of this.notes.values()) {
+    let cnt = 0;
+    for (const note of this.notes) {
+      cnt++;
       const noteNode: Node = {
         id: note.id,
         label: note.text,
@@ -674,15 +660,14 @@ export class ClassDB implements DiagramDB {
           `stroke: ${config.themeVariables.noteBorderColor}`,
         ],
         look: config.look,
-        parentId: note.parent,
       };
       nodes.push(noteNode);
 
-      const noteClassId = this.classes.get(note.class)?.id;
+      const noteClassId = this.classes.get(note.class)?.id ?? '';
 
       if (noteClassId) {
         const edge: Edge = {
-          id: `edgeNote${note.index}`,
+          id: `edgeNote${cnt}`,
           start: note.id,
           end: noteClassId,
           type: 'normal',
@@ -712,7 +697,7 @@ export class ClassDB implements DiagramDB {
       nodes.push(interfaceNode);
     }
 
-    let cnt = 0;
+    cnt = 0;
     for (const classRelation of this.relations) {
       cnt++;
       const edge: Edge = {

packages/mermaid/src/diagrams/class/classDiagram.spec.ts

@@ -417,7 +417,7 @@ class C13["With Città foreign language"]
                      note "This is a keyword: ${keyword}. It truly is."
                   `;
       parser.parse(str);
-      expect(classDb.getNote(0).text).toEqual(`This is a keyword: ${keyword}. It truly is.`);
+      expect(classDb.getNotes()[0].text).toEqual(`This is a keyword: ${keyword}. It truly is.`);
     });
 
     it.each(keywords)(
@@ -427,7 +427,7 @@ class C13["With Città foreign language"]
                       note "${keyword}"`;
 
         parser.parse(str);
-        expect(classDb.getNote(0).text).toEqual(`${keyword}`);
+        expect(classDb.getNotes()[0].text).toEqual(`${keyword}`);
       }
     );
 
@@ -441,7 +441,7 @@ class C13["With Città foreign language"]
                    `;
 
       parser.parse(str);
-      expect(classDb.getNote(0).text).toEqual(`This is a keyword: ${keyword}. It truly is.`);
+      expect(classDb.getNotes()[0].text).toEqual(`This is a keyword: ${keyword}. It truly is.`);
     });
 
     it.each(keywords)(
@@ -456,7 +456,7 @@ class C13["With Città foreign language"]
                     `;
 
         parser.parse(str);
-        expect(classDb.getNote(0).text).toEqual(`${keyword}`);
+        expect(classDb.getNotes()[0].text).toEqual(`${keyword}`);
       }
     );
 

packages/mermaid/src/diagrams/class/classRenderer-v2.ts

@@ -8,7 +8,7 @@ import utils, { getEdgeId } from '../../utils.js';
 import { interpolateToCurve, getStylesFromArray } from '../../utils.js';
 import { setupGraphViewbox } from '../../setupGraphViewbox.js';
 import common from '../common/common.js';
-import type { ClassRelation, ClassMap, ClassNoteMap, NamespaceMap } from './classTypes.js';
+import type { ClassRelation, ClassNote, ClassMap, NamespaceMap } from './classTypes.js';
 import type { EdgeData } from '../../types.js';
 
 const sanitizeText = (txt: string) => common.sanitizeText(txt, getConfig());
@@ -65,9 +65,6 @@ export const addNamespaces = function (
 
     g.setNode(vertex.id, node);
     addClasses(vertex.classes, g, _id, diagObj, vertex.id);
-    const classes: ClassMap = diagObj.db.getClasses();
-    const relations: ClassRelation[] = diagObj.db.getRelations();
-    addNotes(vertex.notes, g, relations.length + 1, classes, vertex.id);
 
     log.info('setNode', node);
   });
@@ -147,74 +144,69 @@ export const addClasses = function (
  * @param classes - Classes
  */
 export const addNotes = function (
-  notes: ClassNoteMap,
+  notes: ClassNote[],
   g: graphlib.Graph,
   startEdgeId: number,
-  classes: ClassMap,
-  parent?: string
+  classes: ClassMap
 ) {
   log.info(notes);
 
-  [...notes.values()]
-    .filter((note) => note.parent === parent)
-    .forEach(function (vertex) {
-      const cssNoteStr = '';
+  notes.forEach(function (note, i) {
+    const vertex = note;
 
-      const styles = { labelStyle: '', style: '' };
+    const cssNoteStr = '';
 
-      const vertexText = vertex.text;
+    const styles = { labelStyle: '', style: '' };
 
-      const radius = 0;
-      const shape = 'note';
-      const node = {
-        labelStyle: styles.labelStyle,
-        shape: shape,
-        labelText: sanitizeText(vertexText),
-        noteData: vertex,
-        rx: radius,
-        ry: radius,
-        class: cssNoteStr,
-        style: styles.style,
-        id: vertex.id,
-        domId: vertex.id,
-        tooltip: '',
-        type: 'note',
-        // TODO V10: Flowchart ? Keeping flowchart for backwards compatibility. Remove in next major release
-        padding: getConfig().flowchart?.padding ?? getConfig().class?.padding,
-      };
-      g.setNode(vertex.id, node);
-      log.info('setNode', node);
+    const vertexText = vertex.text;
 
-      if (parent) {
-        g.setParent(vertex.id, parent);
-      }
+    const radius = 0;
+    const shape = 'note';
+    const node = {
+      labelStyle: styles.labelStyle,
+      shape: shape,
+      labelText: sanitizeText(vertexText),
+      noteData: vertex,
+      rx: radius,
+      ry: radius,
+      class: cssNoteStr,
+      style: styles.style,
+      id: vertex.id,
+      domId: vertex.id,
+      tooltip: '',
+      type: 'note',
+      // TODO V10: Flowchart ? Keeping flowchart for backwards compatibility. Remove in next major release
+      padding: getConfig().flowchart?.padding ?? getConfig().class?.padding,
+    };
+    g.setNode(vertex.id, node);
+    log.info('setNode', node);
 
-      if (!vertex.class || !classes.has(vertex.class)) {
-        return;
-      }
-      const edgeId = startEdgeId + vertex.index;
+    if (!vertex.class || !classes.has(vertex.class)) {
+      return;
+    }
+    const edgeId = startEdgeId + i;
 
-      const edgeData: EdgeData = {
-        id: `edgeNote${edgeId}`,
-        //Set relationship style and line type
-        classes: 'relation',
-        pattern: 'dotted',
-        // Set link type for rendering
-        arrowhead: 'none',
-        //Set edge extra labels
-        startLabelRight: '',
-        endLabelLeft: '',
-        //Set relation arrow types
-        arrowTypeStart: 'none',
-        arrowTypeEnd: 'none',
-        style: 'fill:none',
-        labelStyle: '',
-        curve: interpolateToCurve(conf.curve, curveLinear),
-      };
+    const edgeData: EdgeData = {
+      id: `edgeNote${edgeId}`,
+      //Set relationship style and line type
+      classes: 'relation',
+      pattern: 'dotted',
+      // Set link type for rendering
+      arrowhead: 'none',
+      //Set edge extra labels
+      startLabelRight: '',
+      endLabelLeft: '',
+      //Set relation arrow types
+      arrowTypeStart: 'none',
+      arrowTypeEnd: 'none',
+      style: 'fill:none',
+      labelStyle: '',
+      curve: interpolateToCurve(conf.curve, curveLinear),
+    };
 
-      // Add the edge to the graph
-      g.setEdge(vertex.id, vertex.class, edgeData, edgeId);
-    });
+    // Add the edge to the graph
+    g.setEdge(vertex.id, vertex.class, edgeData, edgeId);
+  });
 };
 
 /**
@@ -337,7 +329,7 @@ export const draw = async function (text: string, id: string, _version: string,
   const namespaces: NamespaceMap = diagObj.db.getNamespaces();
   const classes: ClassMap = diagObj.db.getClasses();
   const relations: ClassRelation[] = diagObj.db.getRelations();
-  const notes: ClassNoteMap = diagObj.db.getNotes();
+  const notes: ClassNote[] = diagObj.db.getNotes();
   log.info(relations);
   addNamespaces(namespaces, g, id, diagObj);
   addClasses(classes, g, id, diagObj);

packages/mermaid/src/diagrams/class/classRenderer.js

@@ -206,7 +206,7 @@ export const draw = function (text, id, _version, diagObj) {
     );
   });
 
-  const notes = diagObj.db.getNotes().values();
+  const notes = diagObj.db.getNotes();
   notes.forEach(function (note) {
     log.debug(`Adding note: ${JSON.stringify(note)}`);
     const node = svgDraw.drawNote(diagram, note, conf, diagObj);

packages/mermaid/src/diagrams/class/classTypes.ts

@@ -5,7 +5,7 @@ export interface ClassNode {
   id: string;
   type: string;
   label: string;
-  shape: 'classBox';
+  shape: string;
   text: string;
   cssClasses: string;
   methods: ClassMember[];
@@ -149,8 +149,6 @@ export interface ClassNote {
   id: string;
   class: string;
   text: string;
-  index: number;
-  parent?: string;
 }
 
 export interface ClassRelation {
@@ -179,7 +177,6 @@ export interface NamespaceNode {
   id: string;
   domId: string;
   classes: ClassMap;
-  notes: ClassNoteMap;
   children: NamespaceMap;
 }
 
@@ -190,5 +187,4 @@ export interface StyleClass {
 }
 
 export type ClassMap = Map<string, ClassNode>;
-export type ClassNoteMap = Map<string, ClassNote>;
 export type NamespaceMap = Map<string, NamespaceNode>;

packages/mermaid/src/diagrams/class/parser/classDiagram.jison

@@ -275,8 +275,8 @@ statement
     ;
 
 namespaceStatement
-    : namespaceIdentifier STRUCT_START classStatements STRUCT_STOP          { yy.addClassesToNamespace($1, $3[0], $3[1]); }
-    | namespaceIdentifier STRUCT_START NEWLINE classStatements STRUCT_STOP  { yy.addClassesToNamespace($1, $4[0], $4[1]); }
+    : namespaceIdentifier STRUCT_START classStatements STRUCT_STOP          { yy.addClassesToNamespace($1, $3); }
+    | namespaceIdentifier STRUCT_START NEWLINE classStatements STRUCT_STOP  { yy.addClassesToNamespace($1, $4); }
     ;
 
 namespaceIdentifier
@@ -284,12 +284,9 @@ namespaceIdentifier
     ;
 
 classStatements
-    : classStatement                            {$$=[[$1], []]}
-    | classStatement NEWLINE                    {$$=[[$1], []]}
-    | classStatement NEWLINE classStatements    {$3[0].unshift($1); $$=$3}
-    | noteStatement                             {$$=[[], [$1]]}
-    | noteStatement NEWLINE                     {$$=[[], [$1]]}
-    | noteStatement NEWLINE classStatements     {$3[1].unshift($1); $$=$3}
+    : classStatement                            {$$=[$1]}
+    | classStatement NEWLINE                    {$$=[$1]}
+    | classStatement NEWLINE classStatements    {$3.unshift($1); $$=$3}
     ;
 
 classStatement
@@ -336,8 +333,8 @@ relationStatement
     ;
 
 noteStatement
-    : NOTE_FOR className noteText  { $$ = yy.addNote($3, $2); }
-    | NOTE noteText                { $$ = yy.addNote($2); }
+    : NOTE_FOR className noteText  { yy.addNote($3, $2); }
+    | NOTE noteText                { yy.addNote($2); }
     ;
 
 classDefStatement

packages/mermaid/src/diagrams/class/styles.js

@@ -13,30 +13,6 @@ const getStyles = (options) =>
 
 }
 
-  .cluster-label text {
-    fill: ${options.titleColor};
-  }
-  .cluster-label span {
-    color: ${options.titleColor};
-  }
-  .cluster-label span p {
-    background-color: transparent;
-  }
-
-  .cluster rect {
-    fill: ${options.clusterBkg};
-    stroke: ${options.clusterBorder};
-    stroke-width: 1px;
-  }
-
-  .cluster text {
-    fill: ${options.titleColor};
-  }
-
-  .cluster span {
-    color: ${options.titleColor};
-  }
-
 .nodeLabel, .edgeLabel {
   color: ${options.classText};
 }

packages/mermaid/src/diagrams/common/common.ts

@@ -333,7 +333,7 @@ const renderKatexUnsanitized = async (text: string, config: MermaidConfig): Prom
     return text.replace(katexRegex, 'MathML is unsupported in this environment.');
   }
 
-  if (injected.includeLargeFeatures) {
+  if (includeLargeFeatures) {
     const { default: katex } = await import('katex');
     const outputMode =
       config.forceLegacyMathML || (!isMathMLSupported() && config.legacyMathML)

packages/mermaid/src/diagrams/flowchart/flowDb.ts

@@ -85,17 +85,6 @@ export class FlowDB implements DiagramDB {
     return common.sanitizeText(txt, this.config);
   }
 
-  private sanitizeNodeLabelType(labelType?: string) {
-    switch (labelType) {
-      case 'markdown':
-      case 'string':
-      case 'text':
-        return labelType;
-      default:
-        return 'markdown';
-    }
-  }
-
   /**
    * Function to lookup domId from id in the graph definition.
    *
@@ -219,7 +208,6 @@ export class FlowDB implements DiagramDB {
 
       if (doc?.label) {
         vertex.text = doc?.label;
-        vertex.labelType = this.sanitizeNodeLabelType(doc?.labelType);
       }
       if (doc?.icon) {
         vertex.icon = doc?.icon;
@@ -279,7 +267,7 @@ export class FlowDB implements DiagramDB {
       if (edge.text.startsWith('"') && edge.text.endsWith('"')) {
         edge.text = edge.text.substring(1, edge.text.length - 1);
       }
-      edge.labelType = this.sanitizeNodeLabelType(linkTextObj.type);
+      edge.labelType = linkTextObj.type;
     }
 
     if (type !== undefined) {
@@ -714,7 +702,7 @@ You have to call mermaid.initialize.`
       title: title.trim(),
       classes: [],
       dir,
-      labelType: this.sanitizeNodeLabelType(_title?.type),
+      labelType: _title.type,
     };
 
     log.info('Adding', subGraph.id, subGraph.nodes, subGraph.dir);
@@ -974,7 +962,6 @@ You have to call mermaid.initialize.`
       case 'round':
         return 'roundedRect';
       case 'ellipse':
-        // @ts-expect-error -- Ellipses are broken, see https://github.com/mermaid-js/mermaid/issues/5976
         return 'ellipse';
       default:
         return vertex.type;
@@ -1024,7 +1011,6 @@ You have to call mermaid.initialize.`
       const baseNode = {
         id: vertex.id,
         label: vertex.text,
-        labelType: vertex.labelType,
         labelStyle: '',
         parentId,
         padding: config.flowchart?.padding || 8,
@@ -1101,7 +1087,6 @@ You have to call mermaid.initialize.`
         id: subGraph.id,
         label: subGraph.title,
         labelStyle: '',
-        labelType: subGraph.labelType,
         parentId: parentDB.get(subGraph.id),
         padding: 8,
         cssCompiledStyles: this.getCompiledStyles(subGraph.classes),
@@ -1133,7 +1118,6 @@ You have to call mermaid.initialize.`
         end: rawEdge.end,
         type: rawEdge.type ?? 'normal',
         label: rawEdge.text,
-        labelType: rawEdge.labelType,
         labelpos: 'c',
         thickness: rawEdge.stroke,
         minlen: rawEdge.length,

packages/mermaid/src/diagrams/flowchart/parser/flow.jison

@@ -140,7 +140,6 @@ that id.
 .*direction\s+BT[^\n]*       return 'direction_bt';
 .*direction\s+RL[^\n]*       return 'direction_rl';
 .*direction\s+LR[^\n]*       return 'direction_lr';
-.*direction\s+TD[^\n]*       return 'direction_td';
 
 [^\s\"]+\@(?=[^\{\"])               { return 'LINK_ID'; }
 [0-9]+                       return 'NUM';
@@ -627,8 +626,6 @@ direction
     { $$={stmt:'dir', value:'RL'};}
     | direction_lr
     { $$={stmt:'dir', value:'LR'};}
-    | direction_td
-    { $$={stmt:'dir', value:'TD'};}
     ;
 
 %%

packages/mermaid/src/diagrams/flowchart/parser/subgraph.spec.js

@@ -309,21 +309,4 @@ describe('when parsing subgraphs', function () {
     expect(subgraphA.nodes).toContain('a');
     expect(subgraphA.nodes).not.toContain('c');
   });
-  it('should correctly parse direction TD inside a subgraph', function () {
-    const res = flow.parser.parse(`
-      graph LR
-        subgraph WithTD
-          direction TD
-          A1 --> A2
-        end
-    `);
-
-    const subgraphs = flow.parser.yy.getSubGraphs();
-    expect(subgraphs.length).toBe(1);
-    const subgraph = subgraphs[0];
-
-    expect(subgraph.dir).toBe('TD');
-    expect(subgraph.nodes).toContain('A1');
-    expect(subgraph.nodes).toContain('A2');
-  });
 });

packages/mermaid/src/diagrams/flowchart/types.ts

@@ -29,7 +29,7 @@ export interface FlowVertex {
   domId: string;
   haveCallback?: boolean;
   id: string;
-  labelType: 'markdown' | 'string' | 'text';
+  labelType: 'text';
   link?: string;
   linkTarget?: string;
   props?: any;
@@ -62,7 +62,7 @@ export interface FlowEdge {
   style?: string[];
   length?: number;
   text: string;
-  labelType: 'markdown' | 'string' | 'text';
+  labelType: 'text';
   classes: string[];
   id?: string;
   animation?: 'fast' | 'slow';

packages/mermaid/src/diagrams/info/infoDb.ts

@@ -1,7 +1,8 @@
 import type { InfoFields, InfoDB } from './infoTypes.js';
+import packageJson from '../../../package.json' assert { type: 'json' };
 
 export const DEFAULT_INFO_DB: InfoFields = {
-  version: injected.version + (injected.includeLargeFeatures ? '' : '-tiny'),
+  version: packageJson.version + (includeLargeFeatures ? '' : '-tiny'),
 } as const;
 
 export const getVersion = (): string => DEFAULT_INFO_DB.version;

packages/mermaid/src/diagrams/kanban/kanbanDb.ts

@@ -62,7 +62,6 @@ const getData = function () {
     const node = {
       id: section.id,
       label: sanitizeText(section.label ?? '', conf),
-      labelType: 'markdown',
       isGroup: true,
       ticket: section.ticket,
       shape: 'kanbanSection',
@@ -77,7 +76,6 @@ const getData = function () {
         id: item.id,
         parentId: section.id,
         label: sanitizeText(item.label ?? '', conf),
-        labelType: 'markdown',
         isGroup: false,
         ticket: item?.ticket,
         priority: item?.priority,

packages/mermaid/src/diagrams/mindmap/mindmapDb.ts

@@ -260,7 +260,6 @@ export class MindmapDB {
       id: node.id.toString(),
       domId: 'node_' + node.id.toString(),
       label: node.descr,
-      labelType: 'markdown',
       isGroup: false,
       shape: getShapeFromType(node.type),
       width: node.width,

packages/mermaid/src/diagrams/mindmap/mindmapTypes.ts

@@ -16,7 +16,6 @@ export interface MindmapNode {
   x?: number;
   y?: number;
   isRoot?: boolean;
-  labelType?: string;
 }
 
 export type FilledMindMapNode = RequiredDeep<MindmapNode>;

packages/mermaid/src/diagrams/packet/renderer.ts

@@ -16,7 +16,7 @@ const draw: DrawDefinition = (_text, id, _version, diagram: Diagram) => {
   const svgWidth = bitWidth * bitsPerRow + 2;
   const svg: SVG = selectSvgElement(id);
 
-  svg.attr('viewBox', `0 0 ${svgWidth} ${svgHeight}`);
+  svg.attr('viewbox', `0 0 ${svgWidth} ${svgHeight}`);
   configureSvgSize(svg, svgHeight, svgWidth, config.useMaxWidth);
 
   for (const [word, packet] of words.entries()) {

packages/mermaid/src/diagrams/radar/renderer.ts

@@ -2,7 +2,6 @@ import type { Diagram } from '../../Diagram.js';
 import type { RadarDiagramConfig } from '../../config.type.js';
 import type { DiagramRenderer, DrawDefinition, SVG, SVGGroup } from '../../diagram-api/types.js';
 import { selectSvgElement } from '../../rendering-util/selectSvgElement.js';
-import { configureSvgSize } from '../../setupGraphViewbox.js';
 import type { RadarDB, RadarAxis, RadarCurve } from './types.js';
 
 const draw: DrawDefinition = (_text, id, _version, diagram: Diagram) => {
@@ -54,9 +53,11 @@ const drawFrame = (svg: SVG, config: Required<RadarDiagramConfig>): SVGGroup =>
     x: config.marginLeft + config.width / 2,
     y: config.marginTop + config.height / 2,
   };
-  configureSvgSize(svg, totalHeight, totalWidth, config.useMaxWidth ?? true);
-
-  svg.attr('viewBox', `0 0 ${totalWidth} ${totalHeight}`);
+  // Initialize the SVG
+  svg
+    .attr('viewbox', `0 0 ${totalWidth} ${totalHeight}`)
+    .attr('width', totalWidth)
+    .attr('height', totalHeight);
   // g element to center the radar chart
   return svg.append('g').attr('transform', `translate(${center.x}, ${center.y})`);
 };

packages/mermaid/src/diagrams/sequence/parser/sequenceDiagram.jison

@@ -32,14 +32,13 @@
 <CONFIG>[^\}]+                                                  { return 'CONFIG_CONTENT'; }
 <CONFIG>\}                                                      { this.popState(); this.popState(); return 'CONFIG_END'; }
 <ID>[^\<->\->:\n,;@\s]+(?=\@\{)                                 { yytext = yytext.trim(); return 'ACTOR'; }
-<ID>[^<>:\n,;@\s]+(?=\s+as\s)                                   { yytext = yytext.trim(); this.begin('ALIAS'); return 'ACTOR'; }
-<ID>[^<>:\n,;@]+(?=\s*[\n;#]|$)                                 { yytext = yytext.trim(); this.popState(); return 'ACTOR'; }
-<ID>[^<>:\n,;@]*\<[^\n]*                                        { this.popState(); return 'INVALID'; }
+<ID>[^\<->\->:\n,;@]+?([\-]*[^\<->\->:\n,;@]+?)*?(?=((?!\n)\s)+"as"(?!\n)\s|[#\n;]|$) { yytext = yytext.trim(); this.begin('ALIAS'); return 'ACTOR'; }
 "box"															{ this.begin('LINE'); return 'box'; }
 "participant"                                                   { this.begin('ID'); return 'participant'; }
 "actor"                                                   		{ this.begin('ID'); return 'participant_actor'; }
 "create"                                                        return 'create';
 "destroy"                                                       { this.begin('ID'); return 'destroy'; }
+<ID>[^<\->\->:\n,;]+?([\-]*[^<\->\->:\n,;]+?)*?(?=((?!\n)\s)+"as"(?!\n)\s|[#\n;]|$)     { yytext = yytext.trim(); this.begin('ALIAS'); return 'ACTOR'; }
 <ALIAS>"as"                                                     { this.popState(); this.popState(); this.begin('LINE'); return 'AS'; }
 <ALIAS>(?:)                                                     { this.popState(); this.popState(); return 'NEWLINE'; }
 "loop"                                                          { this.begin('LINE'); return 'loop'; }
@@ -146,7 +145,6 @@ line
 	: SPACE statement { $$ = $2 }
 	| statement { $$ = $1 }
 	| NEWLINE { $$=[]; }
-	| INVALID { $$=[]; }
 	;
 
 box_section
@@ -413,4 +411,4 @@ text2
   : TXT {$$ = yy.parseMessage($1.trim().substring(1)) }
   ;
 
-%%
+%%

packages/mermaid/src/diagrams/sequence/sequenceDiagram.spec.js

@@ -2609,17 +2609,5 @@ Bob->>Alice:Got it!
       expect(actors.get('E').type).toBe('entity');
       expect(actors.get('E').description).toBe('E');
     });
-    it('should handle fail parsing when alias token causes conflicts in participant definition', async () => {
-      let error = false;
-      try {
-        await Diagram.fromText(`
-        sequenceDiagram
-        participant SAS MyServiceWithMoreThan20Chars <br> service decription
-       `);
-      } catch (e) {
-        error = true;
-      }
-      expect(error).toBe(true);
-    });
   });
 });

packages/mermaid/src/diagrams/usecase/styles.ts

@@ -0,0 +1,87 @@
+const getStyles = (options: any) =>
+  `
+  .actor {
+    stroke: ${options.primaryColor};
+    fill: ${options.primaryColor};
+  }
+  
+  .actor-label {
+    fill: ${options.primaryTextColor};
+    font-family: ${options.fontFamily};
+    font-size: 14px;
+    font-weight: normal;
+  }
+  
+  .usecase-actor-shape line {
+    stroke: ${options.actorBorder};
+    fill: ${options.actorBkg};
+  }
+  .usecase-actor-shape circle, line {
+    stroke: ${options.actorBorder};
+    fill: ${options.actorBkg};
+    stroke-width: 2px;
+  }
+  
+  .usecase {
+    stroke: ${options.primaryColor};
+    fill: ${options.primaryColor};
+  }
+  
+  .usecase-label {
+    fill: ${options.primaryTextColor};
+    font-family: ${options.fontFamily};
+    font-size: 12px;
+    font-weight: normal;
+  }
+
+  /* Ellipse shape styling for use cases */
+  .usecase-element ellipse {
+    fill: ${options.mainBkg ?? '#ffffff'};
+    stroke: ${options.primaryColor};
+    stroke-width: 2px;
+  }
+
+  .usecase-element .label {
+    fill: ${options.primaryTextColor};
+    font-family: ${options.fontFamily};
+    font-size: 12px;
+    font-weight: normal;
+    text-anchor: middle;
+    dominant-baseline: central;
+  }
+
+  /* General ellipse styling */
+  .node ellipse {
+    fill: ${options.mainBkg ?? '#ffffff'};
+    stroke: ${options.nodeBorder ?? options.primaryColor};
+    stroke-width: 1px;
+  }
+  
+  .relationship {
+    stroke: ${options.lineColor};
+    fill: none;
+  }
+  
+  & .marker {
+    fill: ${options.lineColor};
+    stroke: ${options.lineColor};
+  }
+  
+  .relationship-label {
+    fill: ${options.primaryTextColor};
+    font-family: ${options.fontFamily};
+    font-size: 10px;
+    font-weight: normal;
+  }
+  
+  .nodeLabel, .edgeLabel {
+  color: ${options.classText};
+  }
+  .system-boundary {
+    fill: ${options.clusterBkg};
+    stroke: ${options.clusterBorder};
+    stroke-width: 1px;
+  }
+`;
+
+export default getStyles;

packages/mermaid/src/diagrams/usecase/usecase.spec.ts

@@ -0,0 +1,98 @@
+import { vi } from 'vitest';
+import { setSiteConfig } from '../../diagram-api/diagramAPI.js';
+import mermaidAPI from '../../mermaidAPI.js';
+import { Diagram } from '../../Diagram.js';
+import { addDiagrams } from '../../diagram-api/diagram-orchestration.js';
+
+beforeAll(async () => {
+  // Is required to load the useCase diagram
+  await Diagram.fromText('usecase\n actor TestActor');
+});
+
+/**
+ * UseCase diagrams require a basic d3 mock for rendering
+ */
+vi.mock('d3', () => {
+  const NewD3 = function (this: any) {
+    function returnThis(this: any) {
+      return this;
+    }
+    return {
+      append: function () {
+        return NewD3();
+      },
+      lower: returnThis,
+      attr: returnThis,
+      style: returnThis,
+      text: returnThis,
+      getBBox: function () {
+        return {
+          height: 10,
+          width: 20,
+        };
+      },
+    };
+  };
+
+  return {
+    select: function () {
+      return new (NewD3 as any)();
+    },
+
+    selectAll: function () {
+      return new (NewD3 as any)();
+    },
+
+    // TODO: In d3 these are CurveFactory types, not strings
+    curveBasis: 'basis',
+    curveBasisClosed: 'basisClosed',
+    curveBasisOpen: 'basisOpen',
+    curveBumpX: 'bumpX',
+    curveBumpY: 'bumpY',
+    curveBundle: 'bundle',
+    curveCardinalClosed: 'cardinalClosed',
+    curveCardinalOpen: 'cardinalOpen',
+    curveCardinal: 'cardinal',
+    curveCatmullRomClosed: 'catmullRomClosed',
+    curveCatmullRomOpen: 'catmullRomOpen',
+    curveCatmullRom: 'catmullRom',
+    curveLinear: 'linear',
+    curveLinearClosed: 'linearClosed',
+    curveMonotoneX: 'monotoneX',
+    curveMonotoneY: 'monotoneY',
+    curveNatural: 'natural',
+    curveStep: 'step',
+    curveStepAfter: 'stepAfter',
+    curveStepBefore: 'stepBefore',
+  };
+});
+// -------------------------------
+
+addDiagrams();
+
+/**
+ * @param conf - Configuration object
+ * @param key - Configuration key
+ * @param value - Configuration value
+ */
+function addConf(conf: any, key: any, value: any) {
+  if (value !== undefined) {
+    conf[key] = value;
+  }
+  return conf;
+}
+
+describe('UseCase diagram with ANTLR parser', () => {
+  it('should parse actors and use cases correctly', async () => {
+    const diagram = await Diagram.fromText(
+      `usecase
+      actor Developer1
+      actor Developer2
+      Developer1 --> a("Login System")
+      Developer2 --> b(Authentication)`
+    );
+
+    expect(diagram).toBeDefined();
+    expect(diagram.type).toBe('usecase');
+  });
+});

packages/mermaid/src/diagrams/usecase/usecaseDb.ts

@@ -0,0 +1,397 @@
+import { log } from '../../logger.js';
+import {
+  setAccTitle,
+  getAccTitle,
+  setDiagramTitle,
+  getDiagramTitle,
+  getAccDescription,
+  setAccDescription,
+  clear as commonClear,
+} from '../common/commonDb.js';
+import type {
+  UsecaseFields,
+  UsecaseDB,
+  Actor,
+  UseCase,
+  SystemBoundary,
+  Relationship,
+  ActorMetadata,
+  Direction,
+  ClassDef,
+} from './usecaseTypes.js';
+import { DEFAULT_DIRECTION, ARROW_TYPE } from './usecaseTypes.js';
+import type { RequiredDeep } from 'type-fest';
+import type { UsecaseDiagramConfig } from '../../config.type.js';
+import DEFAULT_CONFIG from '../../defaultConfig.js';
+import { getConfig as getGlobalConfig } from '../../diagram-api/diagramAPI.js';
+import type { LayoutData, Node, ClusterNode, Edge } from '../../rendering-util/types.js';
+
+export const DEFAULT_USECASE_CONFIG: Required<UsecaseDiagramConfig> = DEFAULT_CONFIG.usecase;
+
+export const DEFAULT_USECASE_DB: RequiredDeep<UsecaseFields> = {
+  actors: new Map(),
+  useCases: new Map(),
+  systemBoundaries: new Map(),
+  relationships: [],
+  classDefs: new Map(),
+  direction: DEFAULT_DIRECTION,
+  config: DEFAULT_USECASE_CONFIG,
+} as const;
+
+let actors = new Map<string, Actor>();
+let useCases = new Map<string, UseCase>();
+let systemBoundaries = new Map<string, SystemBoundary>();
+let relationships: Relationship[] = [];
+let classDefs = new Map<string, ClassDef>();
+let direction: Direction = DEFAULT_DIRECTION;
+const config: Required<UsecaseDiagramConfig> = structuredClone(DEFAULT_USECASE_CONFIG);
+
+const getConfig = (): Required<UsecaseDiagramConfig> => structuredClone(config);
+
+const clear = (): void => {
+  actors = new Map();
+  useCases = new Map();
+  systemBoundaries = new Map();
+  relationships = [];
+  classDefs = new Map();
+  direction = DEFAULT_DIRECTION;
+  commonClear();
+};
+
+// Actor management
+const addActor = (actor: Actor): void => {
+  if (!actor.id || !actor.name) {
+    throw new Error(
+      `Invalid actor: Actor must have both id and name. Received: ${JSON.stringify(actor)}`
+    );
+  }
+
+  if (!actors.has(actor.id)) {
+    actors.set(actor.id, actor);
+    log.debug(`Added actor: ${actor.id} (${actor.name})`);
+  } else {
+    log.debug(`Actor ${actor.id} already exists`);
+  }
+};
+
+const getActors = (): Map<string, Actor> => actors;
+
+const getActor = (id: string): Actor | undefined => actors.get(id);
+
+// UseCase management
+const addUseCase = (useCase: UseCase): void => {
+  if (!useCase.id || !useCase.name) {
+    throw new Error(
+      `Invalid use case: Use case must have both id and name. Received: ${JSON.stringify(useCase)}`
+    );
+  }
+
+  if (!useCases.has(useCase.id)) {
+    useCases.set(useCase.id, useCase);
+    log.debug(`Added use case: ${useCase.id} (${useCase.name})`);
+  } else {
+    log.debug(`Use case ${useCase.id} already exists`);
+  }
+};
+
+const getUseCases = (): Map<string, UseCase> => useCases;
+
+const getUseCase = (id: string): UseCase | undefined => useCases.get(id);
+
+// SystemBoundary management
+const addSystemBoundary = (systemBoundary: SystemBoundary): void => {
+  if (!systemBoundary.id || !systemBoundary.name) {
+    throw new Error(
+      `Invalid system boundary: System boundary must have both id and name. Received: ${JSON.stringify(systemBoundary)}`
+    );
+  }
+
+  if (!systemBoundaries.has(systemBoundary.id)) {
+    systemBoundaries.set(systemBoundary.id, systemBoundary);
+    log.debug(`Added system boundary: ${systemBoundary.name}`);
+  } else {
+    log.debug(`System boundary ${systemBoundary.id} already exists`);
+  }
+};
+
+const getSystemBoundaries = (): Map<string, SystemBoundary> => systemBoundaries;
+
+const getSystemBoundary = (id: string): SystemBoundary | undefined => systemBoundaries.get(id);
+
+// Relationship management
+const addRelationship = (relationship: Relationship): void => {
+  // Validate relationship structure
+  if (!relationship.id || !relationship.from || !relationship.to) {
+    throw new Error(
+      `Invalid relationship: Relationship must have id, from, and to fields. Received: ${JSON.stringify(relationship)}`
+    );
+  }
+
+  if (!relationship.type) {
+    throw new Error(
+      `Invalid relationship: Relationship must have a type. Received: ${JSON.stringify(relationship)}`
+    );
+  }
+
+  // Validate relationship type
+  const validTypes = ['association', 'include', 'extend'];
+  if (!validTypes.includes(relationship.type)) {
+    throw new Error(
+      `Invalid relationship type: ${relationship.type}. Valid types are: ${validTypes.join(', ')}`
+    );
+  }
+
+  // Validate arrow type if present
+  if (relationship.arrowType !== undefined) {
+    const validArrowTypes = [0, 1, 2, 3, 4, 5, 6]; // SOLID_ARROW, BACK_ARROW, LINE_SOLID, CIRCLE_ARROW, CROSS_ARROW
+    if (!validArrowTypes.includes(relationship.arrowType)) {
+      throw new Error(
+        `Invalid arrow type: ${relationship.arrowType}. Valid arrow types are: ${validArrowTypes.join(', ')}`
+      );
+    }
+  }
+
+  relationships.push(relationship);
+  log.debug(
+    `Added relationship: ${relationship.from} -> ${relationship.to} (${relationship.type})`
+  );
+};
+
+const getRelationships = (): Relationship[] => relationships;
+
+// ClassDef management
+const addClassDef = (classDef: ClassDef): void => {
+  if (!classDef.id) {
+    throw new Error(
+      `Invalid classDef: ClassDef must have an id. Received: ${JSON.stringify(classDef)}`
+    );
+  }
+
+  classDefs.set(classDef.id, classDef);
+  log.debug(`Added classDef: ${classDef.id}`);
+};
+
+const getClassDefs = (): Map<string, ClassDef> => classDefs;
+
+const getClassDef = (id: string): ClassDef | undefined => classDefs.get(id);
+
+/**
+ * Get compiled styles from class definitions
+ * Similar to flowchart's getCompiledStyles method
+ */
+const getCompiledStyles = (classNames: string[]): string[] => {
+  let compiledStyles: string[] = [];
+  for (const className of classNames) {
+    const cssClass = classDefs.get(className);
+    if (cssClass?.styles) {
+      compiledStyles = [...compiledStyles, ...(cssClass.styles ?? [])].map((s) => s.trim());
+    }
+  }
+  return compiledStyles;
+};
+
+// Direction management
+const setDirection = (dir: Direction): void => {
+  // Normalize TD to TB (same as flowchart)
+  if (dir === 'TD') {
+    direction = 'TB';
+  } else {
+    direction = dir;
+  }
+  log.debug('Direction set to:', direction);
+};
+
+const getDirection = (): Direction => direction;
+
+// Convert usecase diagram data to LayoutData format for unified rendering
+const getData = (): LayoutData => {
+  const globalConfig = getGlobalConfig();
+  const nodes: Node[] = [];
+  const edges: Edge[] = [];
+
+  // Convert actors to nodes
+  for (const actor of actors.values()) {
+    const classesArray = ['default', 'usecase-actor'];
+    const cssCompiledStyles = getCompiledStyles(classesArray);
+
+    // Determine which shape to use based on whether actor has an icon
+    const actorShape = actor.metadata?.icon ? 'usecaseActorIcon' : 'usecaseActor';
+
+    const node: Node = {
+      id: actor.id,
+      label: actor.name,
+      description: actor.description ? [actor.description] : undefined,
+      shape: actorShape, // Use icon shape if icon is present, otherwise stick figure
+      isGroup: false,
+      padding: 10,
+      look: globalConfig.look,
+      // Add metadata as data attributes for styling
+      cssClasses: `usecase-actor ${
+        actor.metadata && Object.keys(actor.metadata).length > 0
+          ? Object.entries(actor.metadata)
+              .map(([key, value]) => `actor-${key}-${value}`)
+              .join(' ')
+          : ''
+      }`.trim(),
+      cssStyles: actor.styles ?? [], // Direct styles
+      cssCompiledStyles, // Compiled styles from class definitions
+      // Pass actor metadata to the shape handler
+      metadata: actor.metadata,
+    } as Node & { metadata?: ActorMetadata };
+    nodes.push(node);
+  }
+
+  // Convert use cases to nodes
+  for (const useCase of useCases.values()) {
+    // Build CSS classes string
+    let cssClasses = 'usecase-element';
+    const classesArray = ['default', 'usecase-element'];
+    if (useCase.classes && useCase.classes.length > 0) {
+      cssClasses += ' ' + useCase.classes.join(' ');
+      classesArray.push(...useCase.classes);
+    }
+
+    // Get compiled styles from class definitions
+    const cssCompiledStyles = getCompiledStyles(classesArray);
+    const node: Node = {
+      id: useCase.id,
+      label: useCase.name,
+      description: useCase.description ? [useCase.description] : undefined,
+      shape: 'ellipse', // Use ellipse shape for use cases
+      isGroup: false,
+      padding: 10,
+      look: globalConfig.look,
+      cssClasses,
+      cssStyles: useCase.styles ?? [], // Direct styles
+      cssCompiledStyles, // Compiled styles from class definitions
+      // If use case belongs to a system boundary, set parentId
+      ...(useCase.systemBoundary && { parentId: useCase.systemBoundary }),
+    };
+    nodes.push(node);
+  }
+
+  // Convert system boundaries to group nodes
+  for (const boundary of systemBoundaries.values()) {
+    const classesArray = [
+      'default',
+      'system-boundary',
+      `system-boundary-${boundary.type ?? 'rect'}`,
+    ];
+    const cssCompiledStyles = getCompiledStyles(classesArray);
+
+    const node: ClusterNode & { boundaryType?: string } = {
+      id: boundary.id,
+      label: boundary.name,
+      shape: 'usecaseSystemBoundary', // Use custom usecase system boundary cluster shape
+      isGroup: true, // System boundaries are clusters (containers for other nodes)
+      padding: 20,
+      look: globalConfig.look,
+      cssClasses: `system-boundary system-boundary-${boundary.type ?? 'rect'}`,
+      cssStyles: boundary.styles ?? [], // Direct styles
+      cssCompiledStyles, // Compiled styles from class definitions
+      // Pass boundary type to the shape handler
+      boundaryType: boundary.type,
+    };
+    nodes.push(node);
+  }
+
+  // Convert relationships to edges
+  relationships.forEach((relationship, index) => {
+    // Determine arrow types based on relationship.arrowType
+    let arrowTypeEnd = 'none';
+    let arrowTypeStart = 'none';
+
+    switch (relationship.arrowType) {
+      case ARROW_TYPE.SOLID_ARROW: // -->
+        arrowTypeEnd = 'arrow_point';
+        break;
+      case ARROW_TYPE.BACK_ARROW: // <--
+        arrowTypeStart = 'arrow_point';
+        break;
+      case ARROW_TYPE.CIRCLE_ARROW: // --o
+        arrowTypeEnd = 'arrow_circle';
+        break;
+      case ARROW_TYPE.CROSS_ARROW: // --x
+        arrowTypeEnd = 'arrow_cross';
+        break;
+      case ARROW_TYPE.CIRCLE_ARROW_REVERSED: // o--
+        arrowTypeStart = 'arrow_circle';
+        break;
+      case ARROW_TYPE.CROSS_ARROW_REVERSED: // x--
+        arrowTypeStart = 'arrow_cross';
+        break;
+      case ARROW_TYPE.LINE_SOLID: // --
+        // Both remain 'none'
+        break;
+    }
+
+    const edge: Edge = {
+      id: relationship.id || `edge-${index}`,
+      start: relationship.from,
+      end: relationship.to,
+      source: relationship.from,
+      target: relationship.to,
+      label: relationship.label,
+      labelpos: 'c', // Center label position for proper dagre layout
+      type: relationship.type,
+      arrowTypeEnd,
+      arrowTypeStart,
+      classes: `relationship relationship-${relationship.type}`,
+      look: globalConfig.look,
+      thickness: 'normal',
+      pattern: 'solid',
+    };
+    edges.push(edge);
+  });
+
+  return {
+    nodes,
+    edges,
+    config: globalConfig,
+    // Additional properties that layout algorithms might expect
+    type: 'usecase',
+    layoutAlgorithm: 'dagre', // Default layout algorithm
+    direction: getDirection(), // Use the current direction setting
+    nodeSpacing: 50, // Default node spacing
+    rankSpacing: 50, // Default rank spacing
+    markers: ['arrow_point'], // Arrow point markers used in usecase diagrams
+  };
+};
+
+export const db: UsecaseDB = {
+  getConfig,
+
+  clear,
+  setDiagramTitle,
+  getDiagramTitle,
+  setAccTitle,
+  getAccTitle,
+  setAccDescription,
+  getAccDescription,
+
+  addActor,
+  getActors,
+  getActor,
+
+  addUseCase,
+  getUseCases,
+  getUseCase,
+
+  addSystemBoundary,
+  getSystemBoundaries,
+  getSystemBoundary,
+
+  addRelationship,
+  getRelationships,
+
+  addClassDef,
+  getClassDefs,
+  getClassDef,
+
+  // Direction management
+  setDirection,
+  getDirection,
+
+  // Add getData method for unified rendering
+  getData,
+};

packages/mermaid/src/diagrams/usecase/usecaseDetector.ts

@@ -0,0 +1,22 @@
+import type {
+  DiagramDetector,
+  DiagramLoader,
+  ExternalDiagramDefinition,
+} from '../../diagram-api/types.js';
+
+const id = 'usecase';
+
+const detector: DiagramDetector = (txt) => {
+  return /^\s*usecase/.test(txt);
+};
+
+const loader: DiagramLoader = async () => {
+  const { diagram } = await import('./usecaseDiagram.js');
+  return { id, diagram };
+};
+
+export const usecase: ExternalDiagramDefinition = {
+  id,
+  detector,
+  loader,
+};

packages/mermaid/src/diagrams/usecase/usecaseDiagram.ts

@@ -0,0 +1,12 @@
+import type { DiagramDefinition } from '../../diagram-api/types.js';
+import { parser } from './usecaseParser.js';
+import { db } from './usecaseDb.js';
+import { renderer } from './usecaseRenderer.js';
+import styles from './styles.js';
+
+export const diagram: DiagramDefinition = {
+  parser,
+  db,
+  renderer,
+  styles,
+};

packages/mermaid/src/diagrams/usecase/usecaseParser.ts

@@ -0,0 +1,188 @@
+// Import ANTLR parser from the parser package
+import { parse } from '@mermaid-js/parser';
+import { log } from '../../logger.js';
+import type { ParserDefinition } from '../../diagram-api/types.js';
+import { populateCommonDb } from '../common/populateCommonDb.js';
+import type {
+  UsecaseDB,
+  Actor,
+  UseCase,
+  SystemBoundary,
+  Relationship,
+  ArrowType,
+  ClassDef,
+} from './usecaseTypes.js';
+import { db } from './usecaseDb.js';
+
+// ANTLR parser result interface
+interface UsecaseParseResult {
+  actors: { id: string; name: string; metadata?: Record<string, string>; styles?: string[] }[];
+  useCases: {
+    id: string;
+    name: string;
+    nodeId?: string;
+    systemBoundary?: string;
+    classes?: string[];
+    styles?: string[];
+  }[];
+  systemBoundaries: {
+    id: string;
+    name: string;
+    useCases: string[];
+    type?: 'package' | 'rect';
+    styles?: string[];
+  }[];
+  relationships: {
+    id: string;
+    from: string;
+    to: string;
+    type: 'association' | 'include' | 'extend';
+    arrowType: number;
+    label?: string;
+  }[];
+  classDefs?: Map<string, { id: string; styles: string[] }>;
+  direction?: string;
+  accDescr?: string;
+  accTitle?: string;
+  title?: string;
+}
+
+/**
+ * Parse usecase diagram using ANTLR parser
+ */
+const parseUsecaseWithAntlr = async (input: string): Promise<UsecaseParseResult> => {
+  // Use the ANTLR parser from @mermaid-js/parser
+  const result = (await parse('usecase', input)) as UsecaseParseResult;
+  return result;
+};
+
+/**
+ * Populate the database with parsed ANTLR results
+ */
+const populateDb = (ast: UsecaseParseResult, db: UsecaseDB) => {
+  // Clear existing data
+  db.clear();
+
+  // Add actors (ANTLR result already has id, name, and metadata)
+  ast.actors.forEach((actorData) => {
+    const actor: Actor = {
+      id: actorData.id,
+      name: actorData.name,
+      metadata: actorData.metadata,
+      styles: actorData.styles,
+    };
+    db.addActor(actor);
+  });
+
+  // Add use cases (ANTLR result already has id, name, nodeId, systemBoundary, and classes)
+  ast.useCases.forEach((useCaseData) => {
+    const useCase: UseCase = {
+      id: useCaseData.id,
+      name: useCaseData.name,
+      nodeId: useCaseData.nodeId,
+      systemBoundary: useCaseData.systemBoundary,
+      classes: useCaseData.classes,
+      styles: useCaseData.styles,
+    };
+    db.addUseCase(useCase);
+  });
+
+  // Add system boundaries
+  if (ast.systemBoundaries) {
+    ast.systemBoundaries.forEach((boundaryData) => {
+      const systemBoundary: SystemBoundary = {
+        id: boundaryData.id,
+        name: boundaryData.name,
+        useCases: boundaryData.useCases,
+        type: boundaryData.type || 'rect', // default to 'rect' if not specified
+        styles: boundaryData.styles,
+      };
+      db.addSystemBoundary(systemBoundary);
+    });
+  }
+
+  // Add relationships (ANTLR result already has proper structure)
+  ast.relationships.forEach((relationshipData) => {
+    const relationship: Relationship = {
+      id: relationshipData.id,
+      from: relationshipData.from,
+      to: relationshipData.to,
+      type: relationshipData.type,
+      arrowType: relationshipData.arrowType as ArrowType,
+      label: relationshipData.label,
+    };
+    db.addRelationship(relationship);
+  });
+
+  // Add class definitions
+  if (ast.classDefs) {
+    ast.classDefs.forEach((classDefData) => {
+      const classDef: ClassDef = {
+        id: classDefData.id,
+        styles: classDefData.styles,
+      };
+      db.addClassDef(classDef);
+    });
+  }
+
+  // Set direction if provided
+  if (ast.direction) {
+    db.setDirection(ast.direction as any);
+  }
+
+  log.debug('Populated usecase database:', {
+    actors: ast.actors.length,
+    useCases: ast.useCases.length,
+    relationships: ast.relationships.length,
+    classDefs: ast.classDefs?.size ?? 0,
+    direction: ast.direction,
+  });
+};
+
+export const parser: ParserDefinition = {
+  parse: async (input: string): Promise<void> => {
+    log.debug('Parsing usecase diagram with ANTLR:', input);
+
+    try {
+      // Use our ANTLR parser
+      const ast: UsecaseParseResult = await parseUsecaseWithAntlr(input);
+      log.debug('ANTLR parsing result:', ast);
+
+      // Populate common database fields
+      populateCommonDb(ast as any, db);
+
+      // Populate the database with validation
+      populateDb(ast, db);
+
+      log.debug('Usecase diagram parsing completed successfully');
+    } catch (error) {
+      log.error('Error parsing usecase diagram:', error);
+
+      // Check if it's a UsecaseParseError from our ANTLR parser
+      if (
+        error &&
+        typeof error === 'object' &&
+        'name' in error &&
+        error.name === 'UsecaseParseError'
+      ) {
+        // Re-throw the detailed error for better error reporting
+        throw error;
+      }
+
+      // For other errors, wrap them in a generic error
+      const errorMessage = error instanceof Error ? error.message : 'Unknown error';
+      const wrappedError = new Error(`Failed to parse usecase diagram: ${errorMessage}`);
+
+      // Add hash property for consistency with other diagram types
+      (wrappedError as any).hash = {
+        text: input.split('\n')[0] || '',
+        token: 'unknown',
+        line: '1',
+        loc: { first_line: 1, last_line: 1, first_column: 1, last_column: 1 },
+        expected: ['valid usecase syntax'],
+      };
+
+      throw wrappedError;
+    }
+  },
+};

packages/mermaid/src/diagrams/usecase/usecaseRenderer.ts

@@ -0,0 +1,48 @@
+import type { DrawDefinition } from '../../diagram-api/types.js';
+import { log } from '../../logger.js';
+import { getDiagramElement } from '../../rendering-util/insertElementsForSize.js';
+import { getRegisteredLayoutAlgorithm, render } from '../../rendering-util/render.js';
+import { setupViewPortForSVG } from '../../rendering-util/setupViewPortForSVG.js';
+import { getConfig } from '../../diagram-api/diagramAPI.js';
+import utils from '../../utils.js';
+import type { UsecaseDB } from './usecaseTypes.js';
+
+/**
+ * Main draw function using unified rendering system
+ */
+const draw: DrawDefinition = async (_text, id, _version, diag) => {
+  log.info('Drawing usecase diagram (unified)', id);
+  const { securityLevel, usecase: conf, layout } = getConfig();
+
+  // The getData method provided in all supported diagrams is used to extract the data from the parsed structure
+  // into the Layout data format
+  const usecaseDb = diag.db as UsecaseDB;
+  const data4Layout = usecaseDb.getData();
+
+  // Create the root SVG - the element is the div containing the SVG element
+  const svg = getDiagramElement(id, securityLevel);
+
+  data4Layout.type = diag.type;
+  data4Layout.layoutAlgorithm = getRegisteredLayoutAlgorithm(layout);
+
+  data4Layout.nodeSpacing = 50; // Default node spacing
+  data4Layout.rankSpacing = 50; // Default rank spacing
+  data4Layout.markers = ['point', 'circle', 'cross']; // Support point, circle, and cross markers
+  data4Layout.diagramId = id;
+
+  log.debug('Usecase layout data:', data4Layout);
+
+  // Use the unified rendering system
+  await render(data4Layout, svg);
+
+  const padding = 8;
+  utils.insertTitle(
+    svg,
+    'usecaseDiagramTitleText',
+    0, // Default title top margin
+    usecaseDb.getDiagramTitle?.() ?? ''
+  );
+  setupViewPortForSVG(svg, padding, 'usecaseDiagram', conf?.useMaxWidth ?? false);
+};
+
+export const renderer = { draw };

packages/mermaid/src/diagrams/usecase/usecaseStyles.ts

@@ -0,0 +1,40 @@
+const getStyles = (options: any) =>
+  `
+  .actor {
+    stroke: ${options.primaryColor};
+    fill: ${options.primaryColor};
+  }
+  
+  .actor-label {
+    fill: ${options.primaryTextColor};
+    font-family: ${options.fontFamily};
+    font-size: 14px;
+    font-weight: normal;
+  }
+  
+  .usecase {
+    stroke: ${options.primaryColor};
+    fill: ${options.primaryColor};
+  }
+  
+  .usecase-label {
+    fill: ${options.primaryTextColor};
+    font-family: ${options.fontFamily};
+    font-size: 12px;
+    font-weight: normal;
+  }
+  
+  .relationship {
+    stroke: ${options.primaryColor};
+    fill: ${options.primaryColor};
+  }
+  
+  .relationship-label {
+    fill: ${options.primaryTextColor};
+    font-family: ${options.fontFamily};
+    font-size: 10px;
+    font-weight: normal;
+  }
+`;
+
+export default getStyles;

packages/mermaid/src/diagrams/usecase/usecaseTypes.ts

@@ -0,0 +1,113 @@
+import type { DiagramDB } from '../../diagram-api/types.js';
+import type { UsecaseDiagramConfig } from '../../config.type.js';
+import type { LayoutData } from '../../rendering-util/types.js';
+
+export type ActorMetadata = Record<string, string>;
+
+export interface Actor {
+  id: string;
+  name: string;
+  description?: string;
+  metadata?: ActorMetadata;
+  styles?: string[]; // Direct CSS styles applied to this actor
+}
+
+export interface UseCase {
+  id: string;
+  name: string;
+  description?: string;
+  nodeId?: string; // Optional node ID (e.g., 'a' in 'a(Go through code)')
+  systemBoundary?: string; // Optional reference to system boundary
+  classes?: string[]; // CSS classes applied to this use case
+  styles?: string[]; // Direct CSS styles applied to this use case
+}
+
+export type SystemBoundaryType = 'package' | 'rect';
+
+export interface SystemBoundary {
+  id: string;
+  name: string;
+  useCases: string[]; // Array of use case IDs within this boundary
+  type?: SystemBoundaryType; // Type of boundary rendering (default: 'rect')
+  styles?: string[]; // Direct CSS styles applied to this system boundary
+}
+
+// Arrow types for usecase diagrams (matching parser types)
+export const ARROW_TYPE = {
+  SOLID_ARROW: 0, // -->
+  BACK_ARROW: 1, // <--
+  LINE_SOLID: 2, // --
+  CIRCLE_ARROW: 3, // --o
+  CROSS_ARROW: 4, // --x
+  CIRCLE_ARROW_REVERSED: 5, // o--
+  CROSS_ARROW_REVERSED: 6, // x--
+} as const;
+
+export type ArrowType = (typeof ARROW_TYPE)[keyof typeof ARROW_TYPE];
+
+export interface Relationship {
+  id: string;
+  from: string;
+  to: string;
+  type: 'association' | 'include' | 'extend';
+  arrowType: ArrowType;
+  label?: string;
+}
+
+// Direction types for usecase diagrams
+export type Direction = 'TB' | 'TD' | 'BT' | 'RL' | 'LR';
+
+export const DEFAULT_DIRECTION: Direction = 'LR';
+
+export interface ClassDef {
+  id: string;
+  styles: string[];
+}
+
+export interface UsecaseFields {
+  actors: Map<string, Actor>;
+  useCases: Map<string, UseCase>;
+  systemBoundaries: Map<string, SystemBoundary>;
+  relationships: Relationship[];
+  classDefs: Map<string, ClassDef>;
+  direction: Direction;
+  config: Required<UsecaseDiagramConfig>;
+}
+
+export interface UsecaseDB extends DiagramDB {
+  getConfig: () => Required<UsecaseDiagramConfig>;
+
+  // Actor management
+  addActor: (actor: Actor) => void;
+  getActors: () => Map<string, Actor>;
+  getActor: (id: string) => Actor | undefined;
+
+  // UseCase management
+  addUseCase: (useCase: UseCase) => void;
+  getUseCases: () => Map<string, UseCase>;
+  getUseCase: (id: string) => UseCase | undefined;
+
+  // SystemBoundary management
+  addSystemBoundary: (systemBoundary: SystemBoundary) => void;
+  getSystemBoundaries: () => Map<string, SystemBoundary>;
+  getSystemBoundary: (id: string) => SystemBoundary | undefined;
+
+  // Relationship management
+  addRelationship: (relationship: Relationship) => void;
+  getRelationships: () => Relationship[];
+
+  // ClassDef management
+  addClassDef: (classDef: ClassDef) => void;
+  getClassDefs: () => Map<string, ClassDef>;
+  getClassDef: (id: string) => ClassDef | undefined;
+
+  // Direction management
+  setDirection: (direction: Direction) => void;
+  getDirection: () => Direction;
+
+  // Unified rendering support
+  getData: () => LayoutData;
+
+  // Utility methods
+  clear: () => void;
+}

packages/mermaid/src/docs/.vitepress/config.ts

@@ -1,6 +1,6 @@
 import type { MarkdownOptions } from 'vitepress';
 import { defineConfig } from 'vitepress';
-import packageJson from '../../../package.json' with { type: 'json' };
+import packageJson from '../../../package.json' assert { type: 'json' };
 import { addCanonicalUrls } from './canonical-urls.js';
 import MermaidExample from './mermaid-markdown-all.js';
 

packages/mermaid/src/docs/ecosystem/integrations-community.md

@@ -52,8 +52,6 @@ To add an integration to this list, see the [Integrations - create page](./integ
   - [GitHub Writer](https://github.com/ckeditor/github-writer)
   - [SVG diagram generator](https://github.com/SimonKenyonShepard/mermaidjs-github-svg-generator)
 - [GitLab](https://docs.gitlab.com/ee/user/markdown.html#diagrams-and-flowcharts) ✅
-- [GNU Octave](https://octave.org/) ✅
-  - [octave_mermaid_js](https://github.com/CNOCTAVE/octave_mermaid_js) ✅
 - [Mermaid Plugin for JetBrains IDEs](https://plugins.jetbrains.com/plugin/20146-mermaid)
 - [MonsterWriter](https://www.monsterwriter.com/) ✅
 - [Joplin](https://joplinapp.org) ✅
@@ -269,7 +267,6 @@ Communication tools and platforms
   - [reveal.js-mermaid-plugin](https://github.com/ludwick/reveal.js-mermaid-plugin)
 - [Reveal CK](https://github.com/jedcn/reveal-ck)
   - [reveal-ck-mermaid-plugin](https://github.com/tmtm/reveal-ck-mermaid-plugin)
-- [speccharts: Turn your test suites into specification diagrams](https://github.com/arnaudrenaud/speccharts)
 - [Vitepress Plugin](https://github.com/sametcn99/vitepress-mermaid-renderer)
 
 <!--- cspell:ignore Blazorade HueHive --->

packages/mermaid/src/docs/ecosystem/mermaid-chart.md

@@ -41,7 +41,7 @@ Try the Ultimate AI, Mermaid, and Visual Diagramming Suite by creating an accoun
 
 ## Plans
 
-- **Free** - A free plan that includes six diagrams.
+- **Free** - A free plan that includes three diagrams.
 
 - **Pro** - A paid plan that includes unlimited diagrams, access to the collaboration feature, and more.
 

packages/mermaid/src/docs/syntax/classDiagram.md

@@ -15,7 +15,7 @@ title: Animal example
 classDiagram
     note "From Duck till Zebra"
     Animal <|-- Duck
-    note for Duck "can fly<br>can swim<br>can dive<br>can help in debugging"
+    note for Duck "can fly\ncan swim\ncan dive\ncan help in debugging"
     Animal <|-- Fish
     Animal <|-- Zebra
     Animal : +int age

packages/mermaid/src/mermaidAPI.ts

@@ -7,6 +7,7 @@ import { select } from 'd3';
 import { compile, serialize, stringify } from 'stylis';
 import DOMPurify from 'dompurify';
 import isEmpty from 'lodash-es/isEmpty.js';
+import packageJson from '../package.json' assert { type: 'json' };
 import { addSVGa11yTitleDescription, setA11yDiagramInfo } from './accessibility.js';
 import assignWithDepth from './assignWithDepth.js';
 import * as configApi from './config.js';
@@ -420,12 +421,12 @@ const render = async function (
   // -------------------------------------------------------------------------------
   // Draw the diagram with the renderer
   try {
-    await diag.renderer.draw(text, id, injected.version, diag);
+    await diag.renderer.draw(text, id, packageJson.version, diag);
   } catch (e) {
     if (config.suppressErrorRendering) {
       removeTempElements();
     } else {
-      errorRenderer.draw(text, id, injected.version);
+      errorRenderer.draw(text, id, packageJson.version);
     }
     throw e;
   }

packages/mermaid/src/rendering-util/render.ts

@@ -42,7 +42,7 @@ const registerDefaultLayoutLoaders = () => {
       name: 'dagre',
       loader: async () => await import('./layout-algorithms/dagre/index.js'),
     },
-    ...(injected.includeLargeFeatures
+    ...(includeLargeFeatures
       ? [
           {
             name: 'cose-bilkent',

packages/mermaid/src/rendering-util/rendering-elements/clusters.js

@@ -30,17 +30,11 @@ const rect = async (parent, node) => {
   // Create the label and insert it after the rect
   const labelEl = shapeSvg.insert('g').attr('class', 'cluster-label ');
 
-  let text;
-  if (node.labelType === 'markdown') {
-    text = await createText(labelEl, node.label, {
-      style: node.labelStyle,
-      useHtmlLabels,
-      isNode: true,
-    });
-  } else {
-    const labelElement = await createLabel(node.label, node.labelStyle, false, true);
-    text = labelEl.node()?.appendChild(labelElement);
-  }
+  const text = await createText(labelEl, node.label, {
+    style: node.labelStyle,
+    useHtmlLabels,
+    isNode: true,
+  });
 
   // Get the size of the label
   let bbox = text.getBBox();
@@ -465,6 +459,173 @@ const divider = (parent, node) => {
   return { cluster: shapeSvg, labelBBox: {} };
 };
 
+/**
+ * Custom cluster shape for usecase system boundaries
+ * Supports two types: 'rect' (dashed rectangle) and 'package' (UML package notation)
+ * @param {any} parent
+ * @param {any} node
+ * @returns {any} ShapeSvg
+ */
+const usecaseSystemBoundary = async (parent, node) => {
+  log.info('Creating usecase system boundary for ', node.id, node);
+  const siteConfig = getConfig();
+  const { handDrawnSeed } = siteConfig;
+
+  // Add outer g element
+  const shapeSvg = parent
+    .insert('g')
+    .attr('class', 'cluster usecase-system-boundary ' + node.cssClasses)
+    .attr('id', node.id)
+    .attr('data-look', node.look);
+
+  // Get boundary type from node metadata (default to 'rect')
+  const boundaryType = node.boundaryType || 'rect';
+  shapeSvg.attr('data-boundary-type', boundaryType);
+
+  const useHtmlLabels = evaluate(siteConfig.flowchart?.htmlLabels);
+
+  // Create the label
+  const labelEl = shapeSvg.insert('g').attr('class', 'cluster-label');
+  const text = await createText(labelEl, node.label, {
+    style: node.labelStyle,
+    useHtmlLabels,
+    isNode: true,
+  });
+
+  // Get the size of the label
+  let bbox = text.getBBox();
+  if (evaluate(siteConfig.flowchart?.htmlLabels)) {
+    const div = text.children[0];
+    const dv = select(text);
+    bbox = div.getBoundingClientRect();
+    dv.attr('width', bbox.width);
+    dv.attr('height', bbox.height);
+  }
+
+  // Calculate width with padding (similar to rect cluster)
+  const width = node.width <= bbox.width + node.padding ? bbox.width + node.padding : node.width;
+  if (node.width <= bbox.width + node.padding) {
+    node.diff = (width - node.width) / 2 - node.padding;
+  } else {
+    node.diff = -node.padding;
+  }
+
+  const height = node.height;
+  // Use absolute coordinates from layout engine (like rect cluster does)
+  const x = node.x - width / 2;
+  const y = node.y - height / 2;
+
+  let boundaryRect;
+  const { subGraphTitleTopMargin } = getSubGraphTitleMargins(siteConfig);
+
+  if (boundaryType === 'package') {
+    // Draw package-type boundary (rectangle with separate name box at top)
+    const nameBoxWidth = Math.max(80, bbox.width + 20);
+    const nameBoxHeight = 25;
+
+    if (node.look === 'handDrawn') {
+      const rc = rough.svg(shapeSvg);
+      const options = userNodeOverrides(node, {
+        stroke: 'black',
+        strokeWidth: 2,
+        fill: 'none',
+        seed: handDrawnSeed,
+      });
+
+      // Draw main boundary rectangle
+      const roughRect = rc.rectangle(x, y, width, height, options);
+      boundaryRect = shapeSvg.insert(() => roughRect, ':first-child');
+
+      // Draw name box at top-left
+      const roughNameBox = rc.rectangle(x, y - nameBoxHeight, nameBoxWidth, nameBoxHeight, options);
+      shapeSvg.insert(() => roughNameBox, ':first-child');
+    } else {
+      // Draw main boundary rectangle
+      boundaryRect = shapeSvg
+        .insert('rect', ':first-child')
+        .attr('x', x)
+        .attr('y', y)
+        .attr('width', width)
+        .attr('height', height)
+        .attr('fill', 'none')
+        .attr('stroke', 'black')
+        .attr('stroke-width', 2);
+
+      // Draw name box at top-left
+      shapeSvg
+        .insert('rect', ':first-child')
+        .attr('x', x)
+        .attr('y', y - nameBoxHeight)
+        .attr('width', nameBoxWidth)
+        .attr('height', nameBoxHeight)
+        .attr('fill', 'white')
+        .attr('stroke', 'black')
+        .attr('stroke-width', 2);
+    }
+
+    // Position label in the center of the name box (using absolute coordinates)
+    // The name box is at (x, y - nameBoxHeight), so center the label there
+    labelEl.attr(
+      'transform',
+      `translate(${x + nameBoxWidth / 2 - bbox.width / 2}, ${y - nameBoxHeight})`
+    );
+  } else {
+    // Draw rect-type boundary (simple dashed rectangle)
+    if (node.look === 'handDrawn') {
+      const rc = rough.svg(shapeSvg);
+      const options = userNodeOverrides(node, {
+        stroke: 'black',
+        strokeWidth: 2,
+        fill: 'none',
+        strokeLineDash: [5, 5],
+        seed: handDrawnSeed,
+      });
+
+      const roughRect = rc.rectangle(x, y, width, height, options);
+      boundaryRect = shapeSvg.insert(() => roughRect, ':first-child');
+    } else {
+      // Draw dashed rectangle
+      boundaryRect = shapeSvg
+        .insert('rect', ':first-child')
+        .attr('x', x)
+        .attr('y', y)
+        .attr('width', width)
+        .attr('height', height)
+        .attr('fill', 'none')
+        .attr('stroke', 'black')
+        .attr('stroke-width', 2)
+        .attr('stroke-dasharray', '5,5');
+    }
+
+    // Position label at top-left (using absolute coordinates, same as rect cluster)
+    labelEl.attr(
+      'transform',
+      `translate(${node.x - bbox.width / 2}, ${node.y - node.height / 2 + subGraphTitleTopMargin})`
+    );
+  }
+
+  // Get the bounding box of the boundary rectangle
+  const rectBox = boundaryRect.node().getBBox();
+
+  // Set node properties required by layout engine (similar to rect cluster)
+  node.offsetX = 0;
+  node.width = rectBox.width;
+  node.height = rectBox.height;
+  // Used by layout engine to position subgraph in parent
+  node.offsetY = bbox.height - node.padding / 2;
+
+  // Set intersection function for edge routing
+  node.intersect = function (point) {
+    return intersectRect(node, point);
+  };
+
+  // Return cluster object
+  return {
+    cluster: shapeSvg,
+    labelBBox: bbox,
+  };
+};
+
 const squareRect = rect;
 const shapes = {
   rect,
@@ -473,6 +634,7 @@ const shapes = {
   noteGroup,
   divider,
   kanbanSection,
+  usecaseSystemBoundary,
 };
 
 let clusterElems = new Map();

packages/mermaid/src/rendering-util/rendering-elements/edges.js

@@ -29,7 +29,7 @@ import {
 import rough from 'roughjs';
 import createLabel from './createLabel.js';
 import { addEdgeMarkers } from './edgeMarker.ts';
-import { isLabelStyle } from './shapes/handDrawnShapeStyles.js';
+import { isLabelStyle, styles2String } from './shapes/handDrawnShapeStyles.js';
 
 export const edgeLabels = new Map();
 export const terminalLabels = new Map();
@@ -47,16 +47,14 @@ export const getLabelStyles = (styleArray) => {
 export const insertEdgeLabel = async (elem, edge) => {
   let useHtmlLabels = evaluate(getConfig().flowchart.htmlLabels);
 
-  const labelElement =
-    edge.labelType === 'markdown'
-      ? await createText(elem, edge.label, {
-          style: getLabelStyles(edge.labelStyle),
-          useHtmlLabels,
-          addSvgBackground: true,
-          isNode: false,
-        })
-      : await createLabel(edge.label, getLabelStyles(edge.labelStyle), undefined, false);
-
+  const { labelStyles } = styles2String(edge);
+  edge.labelStyle = labelStyles;
+  const labelElement = await createText(elem, edge.label, {
+    style: edge.labelStyle,
+    useHtmlLabels,
+    addSvgBackground: true,
+    isNode: false,
+  });
   log.info('abc82', edge, edge.labelType);
 
   // Create outer g, edgeLabel, this will be positioned after graph layout
@@ -607,14 +605,6 @@ export const insertEdge = function (
   const edgeStyles = Array.isArray(edge.style) ? edge.style : [edge.style];
   let strokeColor = edgeStyles.find((style) => style?.startsWith('stroke:'));
 
-  let animationClass = '';
-  if (edge.animate) {
-    animationClass = 'edge-animation-fast';
-  }
-  if (edge.animation) {
-    animationClass = 'edge-animation-' + edge.animation;
-  }
-
   let animatedEdge = false;
   if (edge.look === 'handDrawn') {
     const rc = rough.svg(elem);
@@ -630,13 +620,7 @@ export const insertEdge = function (
     svgPath = select(svgPathNode)
       .select('path')
       .attr('id', edge.id)
-      .attr(
-        'class',
-        ' ' +
-          strokeClasses +
-          (edge.classes ? ' ' + edge.classes : '') +
-          (animationClass ? ' ' + animationClass : '')
-      )
+      .attr('class', ' ' + strokeClasses + (edge.classes ? ' ' + edge.classes : ''))
       .attr('style', edgeStyles ? edgeStyles.reduce((acc, style) => acc + ';' + style, '') : '');
     let d = svgPath.attr('d');
     svgPath.attr('d', d);
@@ -644,6 +628,13 @@ export const insertEdge = function (
   } else {
     const stylesFromClasses = edgeClassStyles.join(';');
     const styles = edgeStyles ? edgeStyles.reduce((acc, style) => acc + style + ';', '') : '';
+    let animationClass = '';
+    if (edge.animate) {
+      animationClass = ' edge-animation-fast';
+    }
+    if (edge.animation) {
+      animationClass = ' edge-animation-' + edge.animation;
+    }
 
     const pathStyle =
       (stylesFromClasses ? stylesFromClasses + ';' + styles + ';' : styles) +
@@ -655,10 +646,7 @@ export const insertEdge = function (
       .attr('id', edge.id)
       .attr(
         'class',
-        ' ' +
-          strokeClasses +
-          (edge.classes ? ' ' + edge.classes : '') +
-          (animationClass ? ' ' + animationClass : '')
+        ' ' + strokeClasses + (edge.classes ? ' ' + edge.classes : '') + (animationClass ?? '')
       )
       .attr('style', pathStyle);
 

packages/mermaid/src/rendering-util/rendering-elements/markers.js

@@ -130,6 +130,7 @@ const lollipop = (elem, type, id) => {
     .attr('markerHeight', 240)
     .attr('orient', 'auto')
     .append('circle')
+    .attr('stroke', 'black')
     .attr('fill', 'transparent')
     .attr('cx', 7)
     .attr('cy', 7)
@@ -146,6 +147,7 @@ const lollipop = (elem, type, id) => {
     .attr('markerHeight', 240)
     .attr('orient', 'auto')
     .append('circle')
+    .attr('stroke', 'black')
     .attr('fill', 'transparent')
     .attr('cx', 7)
     .attr('cy', 7)

packages/mermaid/src/rendering-util/rendering-elements/shapes.ts

@@ -14,6 +14,7 @@ import { curvedTrapezoid } from './shapes/curvedTrapezoid.js';
 import { cylinder } from './shapes/cylinder.js';
 import { dividedRectangle } from './shapes/dividedRect.js';
 import { doublecircle } from './shapes/doubleCircle.js';
+import { ellipse } from './shapes/ellipse.js';
 import { filledCircle } from './shapes/filledCircle.js';
 import { flippedTriangle } from './shapes/flippedTriangle.js';
 import { forkJoin } from './shapes/forkJoin.js';
@@ -32,6 +33,8 @@ import { lean_right } from './shapes/leanRight.js';
 import { lightningBolt } from './shapes/lightningBolt.js';
 import { linedCylinder } from './shapes/linedCylinder.js';
 import { linedWaveEdgedRect } from './shapes/linedWaveEdgedRect.js';
+import { usecaseActor } from './shapes/usecaseActor.js';
+import { usecaseActorIcon } from './shapes/usecaseActorIcon.js';
 import { multiRect } from './shapes/multiRect.js';
 import { multiWaveEdgedRectangle } from './shapes/multiWaveEdgedRectangle.js';
 import { note } from './shapes/note.js';
@@ -115,6 +118,14 @@ export const shapesDefs = [
     aliases: ['terminal', 'pill'],
     handler: stadium,
   },
+  {
+    semanticName: 'Ellipse',
+    name: 'Ellipse',
+    shortName: 'ellipse',
+    description: 'Ellipse shape',
+    aliases: ['oval'],
+    handler: ellipse,
+  },
   {
     semanticName: 'Subprocess',
     name: 'Framed Rectangle',
@@ -507,6 +518,10 @@ const generateShapeMap = () => {
 
     // Requirement diagram
     requirementBox,
+
+    // Usecase diagram
+    usecaseActor,
+    usecaseActorIcon,
   } as const;
 
   const entries = [

packages/mermaid/src/rendering-util/rendering-elements/shapes/ellipse.ts

@@ -0,0 +1,60 @@
+import rough from 'roughjs';
+import type { Bounds, D3Selection, Point } from '../../../types.js';
+import type { Node } from '../../types.js';
+import intersect from '../intersect/index.js';
+import { styles2String, userNodeOverrides } from './handDrawnShapeStyles.js';
+import { getNodeClasses, labelHelper, updateNodeBounds } from './util.js';
+
+export async function ellipse<T extends SVGGraphicsElement>(parent: D3Selection<T>, node: Node) {
+  const { labelStyles, nodeStyles } = styles2String(node);
+  node.labelStyle = labelStyles;
+  const { shapeSvg, bbox, halfPadding } = await labelHelper(parent, node, getNodeClasses(node));
+
+  // Calculate ellipse dimensions with padding
+  const padding = halfPadding ?? 10;
+  const radiusX = bbox.width / 2 + padding * 2;
+  const radiusY = bbox.height / 2 + padding;
+
+  let ellipseElem;
+  const { cssStyles } = node;
+
+  if (node.look === 'handDrawn') {
+    // @ts-expect-error -- Passing a D3.Selection seems to work for some reason
+    const rc = rough.svg(shapeSvg);
+    const options = userNodeOverrides(node, {});
+    const roughNode = rc.ellipse(0, 0, radiusX * 2, radiusY * 2, options);
+
+    ellipseElem = shapeSvg.insert(() => roughNode, ':first-child');
+    ellipseElem.attr('class', 'basic label-container');
+
+    if (cssStyles) {
+      ellipseElem.attr('style', cssStyles);
+    }
+  } else {
+    ellipseElem = shapeSvg
+      .insert('ellipse', ':first-child')
+      .attr('class', 'basic label-container')
+      .attr('style', nodeStyles)
+      .attr('rx', radiusX)
+      .attr('ry', radiusY)
+      .attr('cx', 0)
+      .attr('cy', 0);
+  }
+
+  node.width = radiusX * 2;
+  node.height = radiusY * 2;
+
+  updateNodeBounds(node, ellipseElem);
+
+  node.calcIntersect = function (bounds: Bounds, point: Point) {
+    const rx = bounds.width / 2;
+    const ry = bounds.height / 2;
+    return intersect.ellipse(bounds, rx, ry, point);
+  };
+
+  node.intersect = function (point) {
+    return intersect.ellipse(node, radiusX, radiusY, point);
+  };
+
+  return shapeSvg;
+}

packages/mermaid/src/rendering-util/rendering-elements/shapes/erBox.ts

@@ -62,12 +62,9 @@ export async function erBox<T extends SVGGraphicsElement>(parent: D3Selection<T>
 
     // drawRect doesn't center non-htmlLabels correctly as of now, so translate label
     if (!evaluate(config.htmlLabels)) {
-      const textElement = shapeSvg.select('.label text');
-      const textNode = textElement.node() as SVGTextElement;
-      if (textNode) {
-        const bbox = textNode.getBBox();
-        textElement.attr('transform', `translate(${-bbox.width / 2}, 0)`);
-      }
+      const textElement = shapeSvg.select('text');
+      const bbox = (textElement.node() as SVGTextElement)?.getBBox();
+      textElement.attr('transform', `translate(${-bbox.width / 2}, 0)`);
     }
     return shapeSvg;
   }

packages/mermaid/src/rendering-util/rendering-elements/shapes/usecaseActor.ts

@@ -0,0 +1,168 @@
+import { labelHelper, updateNodeBounds, getNodeClasses } from './util.js';
+import type { Node } from '../../types.js';
+import { styles2String, userNodeOverrides } from './handDrawnShapeStyles.js';
+import rough from 'roughjs';
+import type { D3Selection } from '../../../types.js';
+import intersect from '../intersect/index.js';
+
+/**
+ * Get actor styling based on metadata
+ */
+const getActorStyling = (metadata?: Record<string, string>) => {
+  const defaults = {
+    fillColor: 'none',
+    strokeColor: 'black',
+    strokeWidth: 2,
+    type: 'solid',
+  };
+
+  if (!metadata) {
+    return defaults;
+  }
+
+  return {
+    fillColor: metadata.type === 'hollow' ? 'none' : metadata.fillColor || defaults.fillColor,
+    strokeColor: metadata.strokeColor || defaults.strokeColor,
+    strokeWidth: parseInt(metadata.strokeWidth || '2', 10),
+    type: metadata.type || defaults.type,
+  };
+};
+
+/**
+ * Create stick figure path data
+ * This generates the SVG path for a stick figure centered at (x, y)
+ */
+const createStickFigurePathD = (x: number, y: number, scale = 1.5): string => {
+  // Base path template (centered at origin):
+  // M 0 -4 C 4.4183 -4 8 -7.5817 8 -12 C 8 -16.4183 4.4183 -20 0 -20 C -4.4183 -20 -8 -16.4183 -8 -12 C -8 -7.5817 -4.4183 -4 0 -4 Z M 0 -4 V 5 M -10 14.5 L 0 5 M 10 14.5 L 0 5 M -11 0 H 11
+
+  // Scale all coordinates
+  const s = (val: number) => val * scale;
+
+  // Translate the path to the desired position
+  return [
+    // Head (circle using cubic bezier curves)
+    `M ${x + s(0)} ${y + s(-4)}`,
+    `C ${x + s(4.4183)} ${y + s(-4)} ${x + s(8)} ${y + s(-7.5817)} ${x + s(8)} ${y + s(-12)}`,
+    `C ${x + s(8)} ${y + s(-16.4183)} ${x + s(4.4183)} ${y + s(-20)} ${x + s(0)} ${y + s(-20)}`,
+    `C ${x + s(-4.4183)} ${y + s(-20)} ${x + s(-8)} ${y + s(-16.4183)} ${x + s(-8)} ${y + s(-12)}`,
+    `C ${x + s(-8)} ${y + s(-7.5817)} ${x + s(-4.4183)} ${y + s(-4)} ${x + s(0)} ${y + s(-4)}`,
+    'Z',
+    // Body (vertical line from head to torso)
+    `M ${x + s(0)} ${y + s(-4)}`,
+    `V ${y + s(5)}`,
+    // Left leg
+    `M ${x + s(-10)} ${y + s(14.5)}`,
+    `L ${x + s(0)} ${y + s(5)}`,
+    // Right leg
+    `M ${x + s(10)} ${y + s(14.5)}`,
+    `L ${x + s(0)} ${y + s(5)}`,
+    // Arms (horizontal line)
+    `M ${x + s(-11)} ${y + s(0)}`,
+    `H ${x + s(11)}`,
+  ].join(' ');
+};
+
+/**
+ * Draw traditional stick figure
+ */
+const drawStickFigure = (
+  actorGroup: D3Selection<SVGGElement>,
+  styling: ReturnType<typeof getActorStyling>,
+  node: Node
+): void => {
+  const x = 0; // Center at origin
+  const y = -10; // Adjust vertical position
+  actorGroup.attr('class', 'usecase-actor-shape');
+
+  const pathData = createStickFigurePathD(x, y);
+
+  if (node.look === 'handDrawn') {
+    // @ts-expect-error -- Passing a D3.Selection seems to work for some reason
+    const rc = rough.svg(actorGroup);
+    const options = userNodeOverrides(node, {
+      stroke: styling.strokeColor,
+      strokeWidth: styling.strokeWidth,
+      fill: styling.fillColor,
+    });
+
+    // Draw the stick figure using the path
+    const stickFigure = rc.path(pathData, options);
+    actorGroup.insert(() => stickFigure, ':first-child');
+  } else {
+    // Draw the stick figure using standard SVG path
+    actorGroup
+      .append('path')
+      .attr('d', pathData)
+      .attr('fill', styling.fillColor)
+      .attr('stroke', styling.strokeColor)
+      .attr('stroke-width', styling.strokeWidth);
+  }
+};
+
+/**
+ * Custom shape handler for usecase actors (stick figure)
+ */
+export async function usecaseActor<T extends SVGGraphicsElement>(
+  parent: D3Selection<T>,
+  node: Node
+) {
+  const { labelStyles, nodeStyles } = styles2String(node);
+
+  node.labelStyle = labelStyles;
+  const { shapeSvg, bbox, label } = await labelHelper(parent, node, getNodeClasses(node));
+
+  // Get actor metadata from node
+  const metadata = (node as Node & { metadata?: Record<string, string> }).metadata;
+  const styling = getActorStyling(metadata);
+
+  // Create actor group
+  const actorGroup = shapeSvg.append('g');
+
+  // Add metadata as data attributes for CSS styling
+  if (metadata) {
+    Object.entries(metadata).forEach(([key, value]) => {
+      actorGroup.attr(`data-${key}`, value);
+    });
+  }
+
+  // Draw stick figure
+  drawStickFigure(actorGroup, styling, node);
+
+  // Get the actual bounding box of the rendered actor
+  const actorBBox = actorGroup.node()?.getBBox();
+  const actorHeight = actorBBox?.height ?? 70;
+
+  // Actor name (always rendered below the figure)
+  const labelY = actorHeight / 2 + 15; // Position label below the figure
+
+  // Calculate label height from the actual text element
+  const labelBBox = label.node()?.getBBox() ?? { height: 20 };
+  const labelHeight = labelBBox.height + 10; // Space for label below
+  const totalHeight = actorHeight + labelHeight;
+
+  actorGroup.attr('transform', `translate(${0}, ${-totalHeight / 2 + 35})`);
+  label.attr(
+    'transform',
+    `translate(${-bbox.width / 2 - (bbox.x - (bbox.left ?? 0))},${labelY / 2 - 15} )`
+  );
+
+  if (nodeStyles && node.look !== 'handDrawn') {
+    actorGroup.selectChildren('path').attr('style', nodeStyles);
+  }
+
+  // Update node bounds for layout - this will set node.width and node.height from the bounding box
+  updateNodeBounds(node, actorGroup);
+
+  // Override height to include label space
+  // Width is kept from updateNodeBounds as it correctly reflects the actor's visual width
+  node.height = totalHeight;
+
+  // Add intersect function for edge connection points
+  // Use rectangular intersection since the actor has a rectangular bounding box
+  node.intersect = function (point) {
+    return intersect.rect(node, point);
+  };
+
+  return shapeSvg;
+}

packages/mermaid/src/rendering-util/rendering-elements/shapes/usecaseActorIcon.ts

@@ -0,0 +1,156 @@
+import { labelHelper, updateNodeBounds, getNodeClasses } from './util.js';
+import type { Node } from '../../types.js';
+import { styles2String, userNodeOverrides } from './handDrawnShapeStyles.js';
+import { getIconSVG } from '../../icons.js';
+import rough from 'roughjs';
+import type { D3Selection } from '../../../types.js';
+import intersect from '../intersect/index.js';
+
+/**
+ * Get actor styling based on metadata
+ */
+const getActorStyling = (metadata?: Record<string, string>) => {
+  const defaults = {
+    fillColor: 'none',
+    strokeColor: 'black',
+    strokeWidth: 2,
+    type: 'solid',
+  };
+
+  if (!metadata) {
+    return defaults;
+  }
+
+  return {
+    fillColor: metadata.type === 'hollow' ? 'none' : metadata.fillColor || defaults.fillColor,
+    strokeColor: metadata.strokeColor || defaults.strokeColor,
+    strokeWidth: parseInt(metadata.strokeWidth || '2', 10),
+    type: metadata.type || defaults.type,
+  };
+};
+
+/**
+ * Draw actor with icon representation
+ */
+const drawActorWithIcon = async (
+  actorGroup: D3Selection<SVGGElement>,
+  iconName: string,
+  styling: ReturnType<typeof getActorStyling>,
+  node: Node
+): Promise<void> => {
+  const x = 0; // Center at origin
+  const y = -10; // Adjust vertical position
+  const iconSize = 50; // Icon size
+
+  if (node.look === 'handDrawn') {
+    // @ts-expect-error -- Passing a D3.Selection seems to work for some reason
+    const rc = rough.svg(actorGroup);
+    const options = userNodeOverrides(node, {
+      stroke: styling.strokeColor,
+      strokeWidth: styling.strokeWidth,
+      fill: styling.fillColor === 'none' ? 'white' : styling.fillColor,
+    });
+    actorGroup.attr('class', 'usecase-icon');
+    // Create a rectangle background for the icon
+    const iconBg = rc.rectangle(x - 35, y - 40, 50, 50, options);
+    actorGroup.insert(() => iconBg, ':first-child');
+  } else {
+    // Create a rectangle background for the icon
+    actorGroup
+      .append('rect')
+      .attr('x', x - 27.5)
+      .attr('y', y - 42)
+      .attr('width', 55)
+      .attr('height', 55)
+      .attr('rx', 5)
+      .attr('fill', styling.fillColor === 'none' ? 'white' : styling.fillColor)
+      .attr('stroke', styling.strokeColor)
+      .attr('stroke-width', styling.strokeWidth);
+  }
+
+  // Add icon using getIconSVG (like iconCircle.ts does)
+  const iconElem = actorGroup.append('g').attr('class', 'actor-icon');
+  iconElem.html(
+    `<g>${await getIconSVG(iconName, {
+      height: iconSize,
+      width: iconSize,
+      fallbackPrefix: 'fa',
+    })}</g>`
+  );
+
+  // Get icon bounding box for positioning
+  const iconBBox = iconElem.node()?.getBBox();
+  if (iconBBox) {
+    const iconWidth = iconBBox.width;
+    const iconHeight = iconBBox.height;
+    const iconX = iconBBox.x;
+    const iconY = iconBBox.y;
+
+    // Center the icon in the rectangle
+    iconElem.attr(
+      'transform',
+      `translate(${-iconWidth / 2 - iconX}, ${y - 15 - iconHeight / 2 - iconY})`
+    );
+  }
+};
+
+/**
+ * Custom shape handler for usecase actors with icons
+ */
+export async function usecaseActorIcon<T extends SVGGraphicsElement>(
+  parent: D3Selection<T>,
+  node: Node
+) {
+  const { labelStyles } = styles2String(node);
+  node.labelStyle = labelStyles;
+  const { shapeSvg, bbox, label } = await labelHelper(parent, node, getNodeClasses(node));
+
+  // Get actor metadata from node
+  const metadata = (node as Node & { metadata?: Record<string, string> }).metadata;
+  const styling = getActorStyling(metadata);
+
+  // Create actor group
+  const actorGroup = shapeSvg.append('g');
+
+  // Add metadata as data attributes for CSS styling
+  if (metadata) {
+    Object.entries(metadata).forEach(([key, value]) => {
+      actorGroup.attr(`data-${key}`, value);
+    });
+  }
+
+  // Get icon name from metadata
+  const iconName = metadata?.icon ?? 'user';
+  await drawActorWithIcon(actorGroup, iconName, styling, node);
+
+  // Get the actual bounding box of the rendered actor icon
+  const actorBBox = actorGroup.node()?.getBBox();
+  const actorHeight = actorBBox?.height ?? 70;
+
+  // Actor name (always rendered below the figure)
+  const labelY = actorHeight / 2 + 15; // Position label below the figure
+
+  // Calculate label height from the actual text element
+  const labelBBox = label.node()?.getBBox() ?? { height: 20 };
+  const labelHeight = labelBBox.height + 10; // Space for label below
+  const totalHeight = actorHeight + labelHeight;
+  label.attr(
+    'transform',
+    `translate(${-bbox.width / 2 - (bbox.x - (bbox.left ?? 0))},${labelY / 2 - 15})`
+  );
+
+  // Update node bounds for layout - this will set node.width and node.height from the bounding box
+  updateNodeBounds(node, actorGroup);
+
+  // Override height to include label space
+  // Width is kept from updateNodeBounds as it correctly reflects the actor's visual width
+  node.height = totalHeight;
+
+  // Add intersect function for edge connection points
+  // Use rectangular intersection for icon actors
+  node.intersect = function (point) {
+    return intersect.rect(node, point);
+  };
+
+  return shapeSvg;
+}

packages/mermaid/src/rendering-util/rendering-elements/shapes/util.ts

@@ -1,4 +1,3 @@
-import createLabel from '../createLabel.js';
 import { createText } from '../../createText.js';
 import type { Node } from '../../types.js';
 import { getConfig } from '../../../diagram-api/diagramAPI.js';
@@ -14,7 +13,7 @@ export const labelHelper = async <T extends SVGGraphicsElement>(
   _classes?: string
 ) => {
   let cssClasses;
-  const useHtmlLabels = node.useHtmlLabels || evaluate(getConfig()?.flowchart?.htmlLabels);
+  const useHtmlLabels = node.useHtmlLabels || evaluate(getConfig()?.htmlLabels);
   if (!_classes) {
     cssClasses = 'node default';
   } else {
@@ -41,26 +40,14 @@ export const labelHelper = async <T extends SVGGraphicsElement>(
     label = typeof node.label === 'string' ? node.label : node.label[0];
   }
 
-  let text;
-  if (node.labelType === 'markdown') {
-    text = await createText(labelEl, sanitizeText(decodeEntities(label), getConfig()), {
-      useHtmlLabels,
-      width: node.width || getConfig().flowchart?.wrappingWidth,
-      // @ts-expect-error -- This is currently not used. Should this be `classes` instead?
-      cssClasses: 'markdown-node-label',
-      style: node.labelStyle,
-      addSvgBackground: !!node.icon || !!node.img,
-    });
-  } else {
-    const labelElement = await createLabel(
-      sanitizeText(decodeEntities(label), getConfig()),
-      node.labelStyle,
-      false,
-      true
-    );
-    text = labelEl.node()?.appendChild(labelElement);
-  }
-
+  const text = await createText(labelEl, sanitizeText(decodeEntities(label), getConfig()), {
+    useHtmlLabels,
+    width: node.width || getConfig().flowchart?.wrappingWidth,
+    // @ts-expect-error -- This is currently not used. Should this be `classes` instead?
+    cssClasses: 'markdown-node-label',
+    style: node.labelStyle,
+    addSvgBackground: !!node.icon || !!node.img,
+  });
   // Get the size of the label
   let bbox = text.getBBox();
   const halfPadding = (node?.padding ?? 0) / 2;

packages/mermaid/src/schemas/config.schema.yaml

@@ -56,6 +56,7 @@ required:
   - block
   - look
   - radar
+  - usecase
 properties:
   theme:
     description: |
@@ -310,6 +311,8 @@ properties:
     $ref: '#/$defs/BlockDiagramConfig'
   radar:
     $ref: '#/$defs/RadarDiagramConfig'
+  usecase:
+    $ref: '#/$defs/UsecaseDiagramConfig'
   dompurifyConfig:
     title: DOM Purify Configuration
     description: Configuration options to pass to the `dompurify` library.
@@ -2329,6 +2332,57 @@ $defs: # JSON Schema definition (maybe we should move these to a separate file)
         maximum: 1
         default: 0.17
 
+  UsecaseDiagramConfig:
+    title: Usecase Diagram Config
+    allOf: [{ $ref: '#/$defs/BaseDiagramConfig' }]
+    description: The object containing configurations specific for usecase diagrams.
+    type: object
+    unevaluatedProperties: false
+    required:
+      - useMaxWidth
+    properties:
+      actorFontSize:
+        description: Font size for actor labels
+        type: number
+        minimum: 1
+        default: 14
+      actorFontFamily:
+        description: Font family for actor labels
+        type: string
+        default: '"Open Sans", sans-serif'
+      actorFontWeight:
+        description: Font weight for actor labels
+        type: string
+        default: 'normal'
+      usecaseFontSize:
+        description: Font size for usecase labels
+        type: number
+        minimum: 1
+        default: 12
+      usecaseFontFamily:
+        description: Font family for usecase labels
+        type: string
+        default: '"Open Sans", sans-serif'
+      usecaseFontWeight:
+        description: Font weight for usecase labels
+        type: string
+        default: 'normal'
+      actorMargin:
+        description: Margin around actors
+        type: number
+        minimum: 0
+        default: 50
+      usecaseMargin:
+        description: Margin around use cases
+        type: number
+        minimum: 0
+        default: 50
+      diagramPadding:
+        description: Padding around the entire diagram
+        type: number
+        minimum: 0
+        default: 20
+
   FontCalculator:
     title: Font Calculator
     description: |

packages/mermaid/src/type.d.ts

@@ -1,5 +1,2 @@
 // eslint-disable-next-line no-var
-declare var injected: {
-  version: string;
-  includeLargeFeatures: boolean;
-};
+declare var includeLargeFeatures: boolean;

packages/mermaid/src/types.ts

@@ -1,7 +1,6 @@
 export interface NodeMetaData {
   shape?: string;
   label?: string;
-  labelType?: string;
   icon?: string;
   form?: string;
   pos?: 't' | 'b';

packages/parser/CHANGELOG.md

@@ -1,15 +1,5 @@
 # @mermaid-js/parser
 
-## 0.6.3
-
-### Patch Changes
-
-- [#7051](https://github.com/mermaid-js/mermaid/pull/7051) [`63df702`](https://github.com/mermaid-js/mermaid/commit/63df7021462e8dc1f2aaecb9c5febbbbde4c38e3) Thanks [@shubhamparikh2704](https://github.com/shubhamparikh2704)! - Add validation for negative values in pie charts:
-
-  Prevents crashes during parsing by validating values post-parsing.
-
-  Provides clearer, user-friendly error messages for invalid negative inputs.
-
 ## 0.6.2
 
 ### Patch Changes