From a72e958ebf143464f4cd8df90d48f3268aeeea94 Mon Sep 17 00:00:00 2001
From: Alex Yatskov <alex@foosoft.net>
Date: Sat, 23 Jul 2016 13:06:09 -0700
Subject: [PATCH] Support looking up image tags

---
 ext/fg/js/client.js       |  2 +-
 ext/fg/js/source-image.js | 29 ++++++++++++++++-------------
 ext/fg/js/source-range.js |  4 ++--
 3 files changed, 19 insertions(+), 16 deletions(-)

diff --git a/ext/fg/js/client.js b/ext/fg/js/client.js
index 46e4683e..67400f34 100644
--- a/ext/fg/js/client.js
+++ b/ext/fg/js/client.js
@@ -108,7 +108,7 @@ class Client {
             return;
         }
 
-        if (this.lastTextSource !== null && this.lastTextSource.compareOrigin(textSource) === 0) {
+        if (this.lastTextSource !== null && this.lastTextSource.equals(textSource)) {
             return;
         }
 
diff --git a/ext/fg/js/source-image.js b/ext/fg/js/source-image.js
index 187b0a1d..8c87e31e 100644
--- a/ext/fg/js/source-image.js
+++ b/ext/fg/js/source-image.js
@@ -17,40 +17,43 @@
  */
 
 
-class Image {
+class ImageSource {
     constructor(image) {
-
+        this.img = image;
+        this.length = -1;
     }
 
     text() {
+        const text = this.textRaw();
+        return this.length < 0 ? text : text.substring(0, this.length);
+    }
 
+    textRaw() {
+        return this.img.getAttribute('alt') || '';
     }
 
     setLength(length) {
-
+        this.length = length;
     }
 
     containsPoint(point) {
-
+        const rect = this.getRect();
+        return point.x >= rect.left && point.x <= rect.right;
     }
 
     getRect() {
-
-    }
-
-    getPaddedRect() {
-
+        return this.img.getBoundingClientRect();
     }
 
     select() {
-
+        // NOP
     }
 
     deselect() {
-
+        // NOP
     }
 
-    compareOrigin(range) {
-
+    equals(other) {
+        return other.img && other.textRaw() == this.textRaw();
     }
 }
diff --git a/ext/fg/js/source-range.js b/ext/fg/js/source-range.js
index a6c3d722..bd13a1b6 100644
--- a/ext/fg/js/source-range.js
+++ b/ext/fg/js/source-range.js
@@ -63,8 +63,8 @@ class RangeSource {
         selection.removeAllRanges();
     }
 
-    compareOrigin(range) {
-        return range.rng.compareBoundaryPoints(Range.START_TO_START, this.rng);
+    equals(other) {
+        return other.rng && other.rng.compareBoundaryPoints(Range.START_TO_START, this.rng) == 0;
     }
 
     static seekEnd(node, length) {