#945 Rendering of labels and new label positioning algorithm

cypress/integration/rendering/stateDiagram.spec.js

@@ -13,4 +13,33 @@ describe('State diagram', () => {
     );
     cy.get('svg');
   });
+  it('should render a simple state diagrams', () => {
+    imgSnapshotTest(
+      `
+    stateDiagram
+    [*] --> State1
+    State1 --> State2
+    State1 --> State3
+    State1 --> [*]
+      `,
+      { logLevel: 0 }
+    );
+    cy.get('svg');
+  });
+  it('should render a simple state diagrams with labels', () => {
+    imgSnapshotTest(
+      `
+    stateDiagram
+    [*] --> State1
+    State1 --> State2 : Transition 1
+    State1 --> State3 : Transition 2
+    State1 --> State4 : Transition 3
+    State1 --> State5 : Transition 4
+    State2 --> State3 : Transition 5
+    State1 --> [*]
+      `,
+      { logLevel: 0 }
+    );
+    cy.get('svg');
+  });
 });

src/diagrams/state/parser/stateDiagram.jison

@@ -106,7 +106,7 @@ line
 statement
 	: idStatement DESCR
 	| idStatement '-->' idStatement {yy.addRelation($1, $3);}
-	| idStatement '-->' idStatement DESCR
+	| idStatement '-->' idStatement DESCR {yy.addRelation($1, $3, $4.substr(1).trim());}
     | HIDE_EMPTY
     | scale WIDTH
     | COMPOSIT_STATE

src/diagrams/state/stateDb.js

@@ -41,7 +41,7 @@ export const getRelations = function() {
   return relations;
 };
 
-export const addRelation = function(_id1, _id2) {
+export const addRelation = function(_id1, _id2, title) {
   let id1 = _id1;
   let id2 = _id2;
   let type1 = 'default';
@@ -56,10 +56,10 @@ export const addRelation = function(_id1, _id2) {
     id2 = 'end' + startCnt;
     type2 = 'end';
   }
-  console.log(id1, id2);
+  console.log(id1, id2, title);
   addState(id1, type1);
   addState(id2, type2);
-  relations.push({ id1, id2 });
+  relations.push({ id1, id2, title });
 };
 
 export const addMember = function(className, member) {

src/diagrams/state/stateDiagram.spec.js

@@ -304,6 +304,24 @@ describe('state diagram, ', function() {
         note right of NotShooting : This is a note on a composite state
       `;
 
+      parser.parse(str);
+    });
+    xit('should handle if statements', function() {
+      const str = `stateDiagram\n
+      [*] --> "Order Submitted"
+      if "Payment Accepted" then
+        -->[yes] "Pack products"
+        --> "Send parcel"
+        -right-> (*)
+      else
+        ->[no] "Send error message"
+        -->[Cancel Order] [*]
+      endif
+        }
+
+        note right of NotShooting : This is a note on a composite state
+      `;
+
       parser.parse(str);
     });
   });

src/diagrams/state/stateRenderer.js

@@ -4,6 +4,7 @@ import graphlib from 'graphlibrary';
 import { logger } from '../../logger';
 import stateDb from './stateDb';
 import { parser } from './parser/stateDiagram';
+import utils from '../../utils';
 
 parser.yy = stateDb;
 
@@ -136,7 +137,7 @@ const insertMarkers = function(elem) {
     .attr('markerHeight', 28)
     .attr('orient', 'auto')
     .append('path')
-    .attr('d', 'M 18,7 L9,13 L14,7 L9,1 Z');
+    .attr('d', 'M 19,7 L9,13 L14,7 L9,1 Z');
 };
 const drawStart = function(elem, stateDef) {
   logger.info('Rendering class ' + stateDef);
@@ -285,48 +286,67 @@ const drawEdge = function(elem, path, relation) {
     url = url.replace(/\)/g, '\\)');
   }
 
-  svgPath.attr(
-    'marker-start',
-    'url(' + url + '#' + getRelationType(stateDb.relationType.DEPENDENCY) + 'Start' + ')'
-  );
+  // svgPath.attr(
+  //   'marker-start',
+  //   'url(' + url + '#' + getRelationType(stateDb.relationType.DEPENDENCY) + 'Start' + ')'
+  // );
   svgPath.attr(
     'marker-end',
     'url(' + url + '#' + getRelationType(stateDb.relationType.DEPENDENCY) + 'End' + ')'
   );
 
-  let x, y;
-  const l = path.points.length;
-  if (l % 2 !== 0 && l > 1) {
-    const p1 = path.points[Math.floor(l / 2)];
-    const p2 = path.points[Math.ceil(l / 2)];
-    x = (p1.x + p2.x) / 2;
-    y = (p1.y + p2.y) / 2;
-  } else {
-    const p = path.points[Math.floor(l / 2)];
-    x = p.x;
-    y = p.y;
-  }
+  // Figure ou where to put the label given the points
+  // let x, y;
+  // const l = path.points.length;
+  // if (l % 2 !== 0 && l > 1) {
+  //   const p1 = path.points[Math.floor(l / 2)];
+  //   const p2 = path.points[Math.ceil(l / 2)];
+  //   x = (p1.x + p2.x) / 2;
+  //   y = (p1.y + p2.y) / 2;
+  // } else {
+  //   const p = path.points[Math.floor(l / 2)];
+  //   x = p.x;
+  //   y = p.y;
+  // }
+
+  // console.log('calcLabelPosition', utils);
 
   if (typeof relation.title !== 'undefined') {
     const g = elem.append('g').attr('class', 'classLabel');
     const label = g
       .append('text')
       .attr('class', 'label')
-      .attr('x', x)
-      .attr('y', y)
       .attr('fill', 'red')
       .attr('text-anchor', 'middle')
       .text(relation.title);
 
-    window.label = label;
-    const bounds = label.node().getBBox();
+    const { x, y } = utils.calcLabelPosition(path.points);
+    label.attr('x', x).attr('y', y);
 
+    const bounds = label.node().getBBox();
     g.insert('rect', ':first-child')
       .attr('class', 'box')
       .attr('x', bounds.x - conf.padding / 2)
       .attr('y', bounds.y - conf.padding / 2)
       .attr('width', bounds.width + conf.padding)
       .attr('height', bounds.height + conf.padding);
+
+    // Debug points
+    // path.points.forEach(point => {
+    //   g.append('circle')
+    //     .style('stroke', 'red')
+    //     .style('fill', 'red')
+    //     .attr('r', 1)
+    //     .attr('cx', point.x)
+    //     .attr('cy', point.y);
+    // });
+
+    // g.append('circle')
+    //   .style('stroke', 'blue')
+    //   .style('fill', 'blue')
+    //   .attr('r', 1)
+    //   .attr('cx', x)
+    //   .attr('cy', y);
   }
 
   edgeCount++;
@@ -338,7 +358,7 @@ const drawEdge = function(elem, path, relation) {
  * @param {*} stateDef
  */
 const drawState = function(elem, stateDef) {
-  logger.info('Rendering class ' + stateDef);
+  // logger.info('Rendering class ' + stateDef);
 
   const addTspan = function(textEl, txt, isFirst) {
     const tSpan = textEl
@@ -416,14 +436,11 @@ export const draw = function(text, id) {
     // metadata about the node. In this case we're going to add labels to each of
     // our nodes.
     graph.setNode(node.id, node);
-    logger.info('Org height: ' + node.height);
+    // logger.info('Org height: ' + node.height);
   }
 
   const relations = stateDb.getRelations();
   relations.forEach(function(relation) {
-    logger.info(
-      'tjoho' + getGraphId(relation.id1) + getGraphId(relation.id2) + JSON.stringify(relation)
-    );
     graph.setEdge(getGraphId(relation.id1), getGraphId(relation.id2), {
       relation: relation
     });

src/utils.js

@@ -73,8 +73,56 @@ export const interpolateToCurve = (interpolate, defaultCurve) => {
   return d3[curveName] || defaultCurve;
 };
 
+const distance = (p1, p2) =>
+  p1 && p2 ? Math.sqrt(Math.pow(p2.x - p1.x, 2) + Math.pow(p2.y - p1.y, 2)) : 0;
+
+const traverseEdge = points => {
+  let prevPoint;
+  let totalDistance = 0;
+
+  points.forEach(point => {
+    totalDistance += distance(point, prevPoint);
+    prevPoint = point;
+  });
+
+  // Traverse half of total distance along points
+  const distanceToLabel = totalDistance / 2;
+
+  let remainingDistance = distanceToLabel;
+  let center;
+  prevPoint = undefined;
+  points.forEach(point => {
+    if (prevPoint && !center) {
+      const vectorDistance = distance(point, prevPoint);
+      if (vectorDistance < remainingDistance) {
+        remainingDistance -= vectorDistance;
+      } else {
+        // The point is remainingDistance from prevPoint in the vector between prevPoint and point
+        // Calculate the coordinates
+        const distanceRatio = remainingDistance / vectorDistance;
+        if (distanceRatio <= 0) center = prevPoint;
+        if (distanceRatio >= 1) center = { x: point.x, y: point.y };
+        if (distanceRatio > 0 && distanceRatio < 1) {
+          center = {
+            x: (1 - distanceRatio) * prevPoint.x + distanceRatio * point.x,
+            y: (1 - distanceRatio) * prevPoint.y + distanceRatio * point.y
+          };
+        }
+      }
+    }
+    prevPoint = point;
+  });
+  return center;
+};
+
+const calcLabelPosition = points => {
+  const p = traverseEdge(points);
+  return p;
+};
+
 export default {
   detectType,
   isSubstringInArray,
-  interpolateToCurve
+  interpolateToCurve,
+  calcLabelPosition
 };