Merge pull request #6274 from Shahir-47/bug/5955_adjust-diagram-position-with-legend-width

fix: Prevent Legend Labels from Overlapping Diagram Elements in Journey Diagrams

packages/mermaid/src/config.type.ts

@@ -559,6 +559,10 @@ export interface JourneyDiagramConfig extends BaseDiagramConfig {
    * Margin between actors
    */
   leftMargin?: number;
+  /**
+   * Maximum width of actor labels
+   */
+  maxLabelWidth?: number;
   /**
    * Width of actor boxes
    */

packages/mermaid/src/diagrams/user-journey/journeyRenderer.ts

@@ -13,15 +13,17 @@ export const setConf = function (cnf) {
 };
 
 const actors = {};
+let maxWidth = 0;
 
 /** @param diagram - The diagram to draw to. */
 function drawActorLegend(diagram) {
   const conf = getConfig().journey;
-  // Draw the actors
+  const maxLabelWidth = conf.maxLabelWidth;
+  maxWidth = 0;
   let yPos = 60;
+
   Object.keys(actors).forEach((person) => {
     const colour = actors[person].color;
-
     const circleData = {
       cx: 20,
       cy: yPos,
@@ -32,21 +34,90 @@ function drawActorLegend(diagram) {
     };
     svgDraw.drawCircle(diagram, circleData);
 
-    const labelData = {
-      x: 40,
-      y: yPos + 7,
-      fill: '#666',
-      text: person,
-      textMargin: conf.boxTextMargin | 5,
-    };
-    svgDraw.drawText(diagram, labelData);
+    // First, measure the full text width without wrapping.
+    let measureText = diagram.append('text').attr('visibility', 'hidden').text(person);
+    const fullTextWidth = measureText.node().getBoundingClientRect().width;
+    measureText.remove();
 
-    yPos += 20;
+    let lines = [];
+
+    // If the text is naturally within the max width, use it as a single line.
+    if (fullTextWidth <= maxLabelWidth) {
+      lines = [person];
+    } else {
+      // Otherwise, wrap the text using the knuth-plass algorithm.
+      const words = person.split(' '); // Split the text into words.
+      let currentLine = '';
+      measureText = diagram.append('text').attr('visibility', 'hidden');
+
+      words.forEach((word) => {
+        // check the width of the line with the new word.
+        const testLine = currentLine ? `${currentLine} ${word}` : word;
+        measureText.text(testLine);
+        const textWidth = measureText.node().getBoundingClientRect().width;
+
+        if (textWidth > maxLabelWidth) {
+          // If adding the new word exceeds max width, push the current line.
+          if (currentLine) {
+            lines.push(currentLine);
+          }
+          currentLine = word; // Start a new line with the current word.
+
+          // If the word itself is too long, break it with a hyphen.
+          measureText.text(word);
+          if (measureText.node().getBoundingClientRect().width > maxLabelWidth) {
+            let brokenWord = '';
+            for (const char of word) {
+              brokenWord += char;
+              measureText.text(brokenWord + '-');
+              if (measureText.node().getBoundingClientRect().width > maxLabelWidth) {
+                // Push the broken part with a hyphen.
+                lines.push(brokenWord.slice(0, -1) + '-');
+                brokenWord = char;
+              }
+            }
+            currentLine = brokenWord;
+          }
+        } else {
+          // If the line with the new word fits, add the new word to the current line.
+          currentLine = testLine;
+        }
+      });
+
+      // Push the last line.
+      if (currentLine) {
+        lines.push(currentLine);
+      }
+      measureText.remove(); // Remove the text element used for measuring.
+    }
+
+    lines.forEach((line, index) => {
+      const labelData = {
+        x: 40,
+        y: yPos + 7 + index * 20,
+        fill: '#666',
+        text: line,
+        textMargin: conf.boxTextMargin ?? 5,
+      };
+
+      // Draw the text and measure the width.
+      const textElement = svgDraw.drawText(diagram, labelData);
+      const lineWidth = textElement.node().getBoundingClientRect().width;
+
+      // Use conf.leftMargin as the initial spacing baseline,
+      // but expand maxWidth if the line is wider.
+      if (lineWidth > maxWidth && lineWidth > conf.leftMargin - lineWidth) {
+        maxWidth = lineWidth;
+      }
+    });
+
+    yPos += Math.max(20, lines.length * 20);
   });
 }
+
 // TODO: Cleanup?
 const conf = getConfig().journey;
-const LEFT_MARGIN = conf.leftMargin;
+let leftMargin = 0;
 export const draw = function (text, id, version, diagObj) {
   const conf = getConfig().journey;
 
@@ -84,7 +155,8 @@ export const draw = function (text, id, version, diagObj) {
   });
 
   drawActorLegend(diagram);
-  bounds.insert(0, 0, LEFT_MARGIN, Object.keys(actors).length * 50);
+  leftMargin = conf.leftMargin + maxWidth;
+  bounds.insert(0, 0, leftMargin, Object.keys(actors).length * 50);
   drawTasks(diagram, tasks, 0);
 
   const box = bounds.getBounds();
@@ -92,23 +164,23 @@ export const draw = function (text, id, version, diagObj) {
     diagram
       .append('text')
       .text(title)
-      .attr('x', LEFT_MARGIN)
+      .attr('x', leftMargin)
       .attr('font-size', '4ex')
       .attr('font-weight', 'bold')
       .attr('y', 25);
   }
 
   const height = box.stopy - box.starty + 2 * conf.diagramMarginY;
-  const width = LEFT_MARGIN + box.stopx + 2 * conf.diagramMarginX;
+  const width = leftMargin + box.stopx + 2 * conf.diagramMarginX;
 
   configureSvgSize(diagram, height, width, conf.useMaxWidth);
 
   // Draw activity line
   diagram
     .append('line')
-    .attr('x1', LEFT_MARGIN)
+    .attr('x1', leftMargin)
     .attr('y1', conf.height * 4) // One section head + one task + margins
-    .attr('x2', width - LEFT_MARGIN - 4) // Subtract stroke width so arrow point is retained
+    .attr('x2', width - leftMargin - 4) // Subtract stroke width so arrow point is retained
     .attr('y2', conf.height * 4)
     .attr('stroke-width', 4)
     .attr('stroke', 'black')
@@ -234,7 +306,7 @@ export const drawTasks = function (diagram, tasks, verticalPos) {
       }
 
       const section = {
-        x: i * conf.taskMargin + i * conf.width + LEFT_MARGIN,
+        x: i * conf.taskMargin + i * conf.width + leftMargin,
         y: 50,
         text: task.section,
         fill,
@@ -258,7 +330,7 @@ export const drawTasks = function (diagram, tasks, verticalPos) {
     }, {});
 
     // Add some rendering data to the object
-    task.x = i * conf.taskMargin + i * conf.width + LEFT_MARGIN;
+    task.x = i * conf.taskMargin + i * conf.width + leftMargin;
     task.y = taskPos;
     task.width = conf.diagramMarginX;
     task.height = conf.diagramMarginY;

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

@@ -1496,6 +1496,10 @@ $defs: # JSON Schema definition (maybe we should move these to a separate file)
         type: integer
         default: 150
         minimum: 0
+      maxLabelWidth:
+        description: Maximum width of actor labels
+        type: integer
+        default: 360
       width:
         description: Width of actor boxes
         type: integer