Improved space management for text

packages/mermaid/src/diagrams/xychart/chartBuilder/Orchestrator.ts

@@ -17,8 +17,8 @@ export class Orchestrator {
     this.componentStore = {
       title: getChartTitleComponent(chartConfig, chartData),
       plot: getPlotComponent(chartConfig, chartData),
-      xAxis: getAxis(chartData.xAxis, chartConfig.xAxis),
+      xAxis: getAxis(chartData.xAxis, chartConfig.xAxis, chartConfig.fontFamily),
-      yAxis: getAxis(chartData.yAxis, chartConfig.yAxis),
+      yAxis: getAxis(chartData.yAxis, chartConfig.yAxis, chartConfig.fontFamily),
     };
   }
 

packages/mermaid/src/diagrams/xychart/chartBuilder/TextDimensionCalculator.ts

@@ -1,7 +1,7 @@
 import { Dimension } from './Interfaces.js';
 
 export interface ITextDimensionCalculator {
-  getDimension(texts: string[], fontSize: number, fontFamily?: string ): Dimension;
+  getDimension(texts: string[], fontSize: number, fontFamily?: string): Dimension;
 }
 
 export class TextDimensionCalculator implements ITextDimensionCalculator {
@@ -13,3 +13,57 @@ export class TextDimensionCalculator implements ITextDimensionCalculator {
     };
   }
 }
+
+export class TextDimensionCalculatorWithFont implements ITextDimensionCalculator {
+  private container: HTMLSpanElement | null = null;
+  private hiddenElementId = 'mermaid-text-dimension-calculator';
+  constructor(fontFamily?: string) {
+    if (document) {
+      let parentContainer = document.getElementById(this.hiddenElementId);
+      if (!parentContainer) {
+        parentContainer = document.createElement('div');
+        parentContainer.id = this.hiddenElementId;
+        parentContainer.style.position = 'absolute';
+        parentContainer.style.top = '-100px';
+        parentContainer.style.left = '0px';
+        parentContainer.style.visibility = 'hidden';
+        document.body.append(parentContainer);
+      }
+      const fontClassName = `font-${fontFamily}`;
+      const prevContainerAvailable = parentContainer.getElementsByClassName(fontClassName);
+      if (prevContainerAvailable.length > 0) {
+        this.container = prevContainerAvailable.item(0) as HTMLSpanElement;
+      } else {
+        this.container = document.createElement('div');
+        this.container.className = fontClassName;
+        if (fontFamily) {
+          this.container.style.fontFamily = fontFamily;
+        }
+        parentContainer.append(this.container);
+      }
+    }
+  }
+  getDimension(texts: string[], fontSize: number): Dimension {
+    if (!this.container) {
+      return {
+        width: texts.reduce((acc, cur) => Math.max(cur.length, acc), 0) * fontSize,
+        height: fontSize,
+      };
+    }
+
+    const dimension: Dimension = {
+      width: 0,
+      height: 0,
+    };
+
+    this.container.style.fontSize = `${fontSize}px`;
+
+    for (let t of texts) {
+      this.container.innerHTML = t;
+      const bbox = this.container.getBoundingClientRect();
+      dimension.width = Math.max(dimension.width, bbox.width);
+      dimension.height = Math.max(dimension.height, bbox.height);
+    }
+    return dimension;
+  }
+}

packages/mermaid/src/diagrams/xychart/chartBuilder/components/ChartTitle.ts

@@ -1,13 +1,13 @@
-import { ITextDimensionCalculator, TextDimensionCalculator } from '../TextDimensionCalculator.js';
-import {
-  XYChartData,
-  Dimension,
-  BoundingRect,
-  DrawableElem,
-  Point,
-} from '../Interfaces.js';
-import { ChartComponent } from '../Interfaces.js';
 import { XYChartConfig } from '../../../../config.type.js';
+import {
+    BoundingRect,
+    ChartComponent,
+    Dimension,
+    DrawableElem,
+    Point,
+    XYChartData,
+} from '../Interfaces.js';
+import { ITextDimensionCalculator, TextDimensionCalculatorWithFont } from '../TextDimensionCalculator.js';
 
 export class ChartTitle implements ChartComponent {
   private boundingRect: BoundingRect;
@@ -75,6 +75,6 @@ export function getChartTitleComponent(
   chartConfig: XYChartConfig,
   chartData: XYChartData
 ): ChartComponent {
-  const textDimensionCalculator = new TextDimensionCalculator();
+  const textDimensionCalculator = new TextDimensionCalculatorWithFont(chartConfig.fontFamily);
   return new ChartTitle(textDimensionCalculator, chartConfig, chartData);
 }

packages/mermaid/src/diagrams/xychart/chartBuilder/components/axis/index.ts

@@ -1,12 +1,12 @@
+import { XYChartAxisConfig } from '../../../../../config.type.js';
 import {
     AxisDataType,
+    ChartComponent,
     isBandAxisData,
 } from '../../Interfaces.js';
-import { TextDimensionCalculator } from '../../TextDimensionCalculator.js';
+import { TextDimensionCalculatorWithFont } from '../../TextDimensionCalculator.js';
-import { ChartComponent } from '../../Interfaces.js';
 import { BandAxis } from './BandAxis.js';
 import { LinearAxis } from './LinearAxis.js';
-import { XYChartAxisConfig } from '../../../../../config.type.js';
 
 export type AxisPosition = 'left' | 'right' | 'top' | 'bottom';
 
@@ -18,8 +18,8 @@ export interface IAxis extends ChartComponent {
   setRange(range: [number, number]): void;
 }
 
-export function getAxis(data: AxisDataType, axisConfig: XYChartAxisConfig): IAxis {
+export function getAxis(data: AxisDataType, axisConfig: XYChartAxisConfig, fontFamily?: string): IAxis {
-  const textDimansionCalculator = new TextDimensionCalculator();
+  const textDimansionCalculator = new TextDimensionCalculatorWithFont(fontFamily);
   if (isBandAxisData(data)) {
     return new BandAxis(axisConfig, data.categories, data.title, textDimansionCalculator);
   }