From 99b17a494d9ca91abd5cefa1b03e0f7b49185dc2 Mon Sep 17 00:00:00 2001
From: Tim van der Meij <timvandermeij@gmail.com>
Date: Sun, 17 Sep 2017 20:18:22 +0200
Subject: [PATCH] Implement support for polyline annotations

---
 src/core/annotation.js           | 27 ++++++++++++++
 src/display/annotation_layer.js  | 61 +++++++++++++++++++++++++++++++-
 web/annotation_layer_builder.css |  1 +
 3 files changed, 88 insertions(+), 1 deletion(-)

diff --git a/src/core/annotation.js b/src/core/annotation.js
index d3aa434ea..4da77b0b3 100644
--- a/src/core/annotation.js
+++ b/src/core/annotation.js
@@ -87,6 +87,9 @@ class AnnotationFactory {
       case 'Circle':
         return new CircleAnnotation(parameters);
 
+      case 'PolyLine':
+        return new PolylineAnnotation(parameters);
+
       case 'Highlight':
         return new HighlightAnnotation(parameters);
 
@@ -913,6 +916,30 @@ class CircleAnnotation extends Annotation {
   }
 }
 
+class PolylineAnnotation extends Annotation {
+  constructor(parameters) {
+    super(parameters);
+
+    this.data.annotationType = AnnotationType.POLYLINE;
+
+    // The vertices array is an array of numbers representing the alternating
+    // horizontal and vertical coordinates, respectively, of each vertex.
+    // Convert this to an array of objects with x and y coordinates.
+    let dict = parameters.dict;
+    let rawVertices = dict.getArray('Vertices');
+
+    this.data.vertices = [];
+    for (let i = 0, ii = rawVertices.length; i < ii; i += 2) {
+      this.data.vertices.push({
+        x: rawVertices[i],
+        y: rawVertices[i + 1],
+      });
+    }
+
+    this._preparePopup(dict);
+  }
+}
+
 class HighlightAnnotation extends Annotation {
   constructor(parameters) {
     super(parameters);
diff --git a/src/display/annotation_layer.js b/src/display/annotation_layer.js
index de9048da5..3a0dd13cd 100644
--- a/src/display/annotation_layer.js
+++ b/src/display/annotation_layer.js
@@ -80,6 +80,9 @@ class AnnotationElementFactory {
       case AnnotationType.CIRCLE:
         return new CircleAnnotationElement(parameters);
 
+      case AnnotationType.POLYLINE:
+        return new PolylineAnnotationElement(parameters);
+
       case AnnotationType.HIGHLIGHT:
         return new HighlightAnnotationElement(parameters);
 
@@ -601,7 +604,7 @@ class PopupAnnotationElement extends AnnotationElement {
   render() {
     // Do not render popup annotations for parent elements with these types as
     // they create the popups themselves (because of custom trigger divs).
-    const IGNORE_TYPES = ['Line', 'Square', 'Circle'];
+    const IGNORE_TYPES = ['Line', 'Square', 'Circle', 'PolyLine'];
 
     this.container.className = 'popupAnnotation';
 
@@ -911,6 +914,62 @@ class CircleAnnotationElement extends AnnotationElement {
   }
 }
 
+class PolylineAnnotationElement extends AnnotationElement {
+  constructor(parameters) {
+    let isRenderable = !!(parameters.data.hasPopup ||
+                          parameters.data.title || parameters.data.contents);
+    super(parameters, isRenderable, /* ignoreBorder = */ true);
+  }
+
+  /**
+   * Render the polyline annotation's HTML element in the empty container.
+   *
+   * @public
+   * @memberof PolylineAnnotationElement
+   * @returns {HTMLSectionElement}
+   */
+  render() {
+    this.container.className = 'polylineAnnotation';
+
+    // Create an invisible polyline with the same points that acts as the
+    // trigger for the popup. Only the polyline itself should trigger the
+    // popup, not the entire container.
+    let data = this.data;
+    let width = data.rect[2] - data.rect[0];
+    let height = data.rect[3] - data.rect[1];
+    let svg = this.svgFactory.create(width, height);
+
+    // Convert the vertices array to a single points string that the SVG
+    // polyline element expects ("x1,y1 x2,y2 ..."). PDF coordinates are
+    // calculated from a bottom left origin, so transform the polyline
+    // coordinates to a top left origin for the SVG element.
+    let vertices = data.vertices;
+    let points = [];
+    for (let i = 0, ii = vertices.length; i < ii; i++) {
+      let x = vertices[i].x - data.rect[0];
+      let y = data.rect[3] - vertices[i].y;
+      points.push(x + ',' + y);
+    }
+    points = points.join(' ');
+
+    let borderWidth = data.borderStyle.width;
+    let polyline = this.svgFactory.createElement('svg:polyline');
+    polyline.setAttribute('points', points);
+    polyline.setAttribute('stroke-width', borderWidth);
+    polyline.setAttribute('stroke', 'transparent');
+    polyline.setAttribute('fill', 'none');
+
+    svg.appendChild(polyline);
+    this.container.append(svg);
+
+    // Create the popup ourselves so that we can bind it to the polyline
+    // instead of to the entire container (which is the default).
+    this._createPopup(this.container, polyline, data);
+
+    return this.container;
+  }
+}
+
 class HighlightAnnotationElement extends AnnotationElement {
   constructor(parameters) {
     let isRenderable = !!(parameters.data.hasPopup ||
diff --git a/web/annotation_layer_builder.css b/web/annotation_layer_builder.css
index a12048ce6..ef26847ae 100644
--- a/web/annotation_layer_builder.css
+++ b/web/annotation_layer_builder.css
@@ -191,6 +191,7 @@
 .annotationLayer .lineAnnotation svg line,
 .annotationLayer .squareAnnotation svg rect,
 .annotationLayer .circleAnnotation svg ellipse,
+.annotationLayer .polylineAnnotation svg polyline,
 .annotationLayer .stampAnnotation,
 .annotationLayer .fileAttachmentAnnotation {
   cursor: pointer;