Begin switch from inheritance to composition

3 files changed, 22 insertions, 53 deletions

diff --git a/linkHints.js b/linkHints.js
index 6bd84826..36b682b8 100644
--- a/linkHints.js
+++ b/linkHints.js
@@ -11,23 +11,7 @@
  * the range of possibilities by typing the text of the link itself.
  */
 
-var linkHints;
-/*
- * Create the instance of linkHints, specialized based on the user settings.
- */
-function initializeLinkHints() {
-  if (settings.get('filterLinkHints') != "true") // the default hinting system
-    linkHints = utils.extendWithSuper(linkHintsBase, alphabetHints);
-  else
-    linkHints = utils.extendWithSuper(linkHintsBase, filterHints);
-  linkHints.init();
-}
-
-/*
- * A set of common operations shared by any link-hinting system. Some methods
- * are stubbed.
- */
-var linkHintsBase = {
+var linkHints = {
   hintMarkers: [],
   hintMarkerContainingDiv: null,
   // The characters that were typed in while in "link hints" mode.
@@ -40,6 +24,9 @@ var linkHintsBase = {
   cssAdded: false,
   // While in delayMode, all keypresses have no effect.
   delayMode: false,
+  // Handle the link hinting marker generation and matching. Must be initialized after settings have been
+  // loaded.
+  markerMatcher: undefined,
 
   /*
    * To be called after linkHints has been generated from linkHintsBase.
@@ -47,6 +34,7 @@ var linkHintsBase = {
   init: function() {
     this.onKeyDownInMode = this.onKeyDownInMode.bind(this);
     this.onKeyUpInMode = this.onKeyUpInMode.bind(this);
+    this.markerMatcher = settings.get('filterLinkHints') == "true" ? filterHints : alphabetHints;
   },
 
   /* 
@@ -100,7 +88,7 @@ var linkHintsBase = {
     // Initialize the number used to generate the character hints to be as many digits as we need to
     // highlight all the links on the page; we don't want some link hints to have more chars than others.
     var linkHintNumber = 0;
-    this.initSetMarkerAttributes(visibleElements);
+    this.markerMatcher.initSetMarkerAttributes(visibleElements);
     for (var i = 0; i < visibleElements.length; i++) {
       this.hintMarkers.push(this.createMarkerFor(visibleElements[i], linkHintNumber));
       linkHintNumber++;
@@ -123,19 +111,6 @@ var linkHintsBase = {
   },
 
   /*
-   * Sets the data attributes of the marker. Does not need to handle styling
-   * and positioning. MUST set the hintString and innerHTML properties.
-   */ 
-  setMarkerAttributes: function(marker, linkHintNumber) {},
-
-  /*
-   * A hook for any necessary initialization for setMarkerAttributes.  Takes an
-   * array of visible elements. Any return value is ignored.
-   */
-  initSetMarkerAttributes: function(visibleElements) {
-  },
-
-  /*
    * Returns all clickable elements that are not hidden and are in the current viewport.
    * We prune invisible elements partly for performance reasons, but moreso it's to decrease the number
    * of digits needed to enumerate all of the links on screen.
@@ -198,7 +173,7 @@ var linkHintsBase = {
   },
 
   /*
-   * Handles shift and esc keys. The other keys are passed to normalKeyDownHandler.
+   * Handles shift and esc keys. The other keys are passed to markerMatcher.normalKeyDownHandler.
    */
   onKeyDownInMode: function(event) {
     if (this.delayMode)
@@ -214,7 +189,7 @@ var linkHintsBase = {
     if (isEscape(event)) {
       this.deactivateMode();
     } else {
-      var keyResult = this.normalKeyDownHandler(event, this.hintMarkers);
+      var keyResult = this.markerMatcher.matchHintsByKey(event, this.hintMarkers);
       var linksMatched = keyResult.linksMatched;
       var delay = keyResult.delay !== undefined ? keyResult.delay : 0;
       if (linksMatched.length == 0) {
@@ -233,11 +208,6 @@ var linkHintsBase = {
     event.preventDefault();
   },
 
-  /*
-   * Handle all keys other than shift and esc. Return value is ignored.
-   */
-  normalKeyDownHandler: function(event) {},
-
   onKeyUpInMode: function(event) {
     if (event.keyCode == keyCodes.shiftKey && this.openLinkModeToggle) {
       // Revert toggle on whether to open link in new or current tab. 
@@ -325,6 +295,8 @@ var linkHintsBase = {
   deactivateMode: function(delay, callback) {
     var that = this;
     function deactivate() {
+      if (that.markerMatcher.deactivate)
+        that.markerMatcher.deactivate();
       if (that.hintMarkerContainingDiv)
         that.hintMarkerContainingDiv.parentNode.removeChild(that.hintMarkerContainingDiv);
       that.hintMarkerContainingDiv = null;
@@ -350,7 +322,7 @@ var linkHintsBase = {
     var marker = document.createElement("div");
     marker.className = "internalVimiumHintMarker vimiumHintMarker";
     marker.clickableItem = link.element;
-    this.setMarkerAttributes(marker, linkHintNumber);
+    this.markerMatcher.setMarkerAttributes(marker, linkHintNumber);
 
     // Note: this call will be expensive if we modify the DOM in between calls.
     var clientRect = link.rect;
@@ -404,7 +376,7 @@ var alphabetHints = {
     return hintString.join("");
   },
 
-  normalKeyDownHandler: function (event, hintMarkers) {
+  matchHintsByKey: function (event, hintMarkers) {
     var keyChar = getKeyChar(event);
     if (!keyChar)
       return hintMarkers;
@@ -484,7 +456,7 @@ var filterHints = {
     marker.setAttribute("linkText", linkText);
   },
 
-  normalKeyDownHandler: function(event, hintMarkers) {
+  matchHintsByKey: function(event, hintMarkers) {
     var linksMatched;
     if (event.keyCode == keyCodes.backspace || event.keyCode == keyCodes.deleteKey) {
       if (this.linkTextKeystrokeQueue.length == 0 && this.hintKeystrokeQueue.length == 0) {
@@ -522,8 +494,7 @@ var filterHints = {
         // should be rendered invalid (i.e. reset).
         this.hintKeystrokeQueue = [];
         this.linkTextKeystrokeQueue.push(keyChar);
-        matchString = this.linkTextKeystrokeQueue.join("");
-        linksMatched = this.filterLinkHints(matchString);
+        linksMatched = this.filterLinkHints(hintMarkers);
       }
 
       if (linksMatched.length == 1 && !/[0-9]/.test(keyChar)) {
@@ -542,12 +513,12 @@ var filterHints = {
    * only be called when there is a change in linkTextKeystrokeQueue, to
    * avoid undesired renumbering.
   */
-  filterLinkHints: function(searchString) {
+  filterLinkHints: function(hintMarkers) {
     var linksMatched = [];
     var linkSearchString = this.linkTextKeystrokeQueue.join("");
 
-    for (var i = 0; i < this.hintMarkers.length; i++) {
-      var linkMarker = this.hintMarkers[i];
+    for (var i = 0; i < hintMarkers.length; i++) {
+      var linkMarker = hintMarkers[i];
       var matchedLink = linkMarker.getAttribute("linkText").toLowerCase()
                                   .indexOf(linkSearchString.toLowerCase()) >= 0;
 
@@ -562,10 +533,9 @@ var filterHints = {
     return linksMatched;
   },
 
-  deactivateMode: function(delay, callback) {
+  deactivate: function(delay, callback) {
     this.linkTextKeystrokeQueue = [];
     this.labelMap = {};
-    this._super('deactivateMode')(delay, callback);
   }
 
 };
diff --git a/test_harnesses/automated.html b/test_harnesses/automated.html
index bbfa220f..9f1b8007 100644
--- a/test_harnesses/automated.html
+++ b/test_harnesses/automated.html
@@ -60,8 +60,7 @@
               "<a>test</a>" +
               "<a>tress</a>";
             document.getElementById("test-div").innerHTML = testContent;
-            settings.values.filterLinkHints = isFilteredMode ? "true" : "false";
-            initializeLinkHints();
+            linkHints.markerMatcher = alphabetHints;
           }),
 
           tearDown(function() {
@@ -102,7 +101,7 @@
 
         setup(function() {
           stub(settings.values, "filterLinkHints", "false");
-          initializeLinkHints();
+          linkHints.markerMatcher = alphabetHints;
           // we need at least 16 elements to have double-character link hints
           for (var i = 0; i < 16; i++) {
             var link = document.createElement("a");
@@ -135,7 +134,7 @@
 
         setup(function() {
           stub(settings.values, "filterLinkHints", "true");
-          initializeLinkHints();
+          linkHints.markerMatcher = filterHints;
         }),
 
         context("Text hints",
diff --git a/vimiumFrontend.js b/vimiumFrontend.js
index c5b7bdf8..e0b6eb6a 100644
--- a/vimiumFrontend.js
+++ b/vimiumFrontend.js
@@ -60,7 +60,7 @@ var settings = {
   },
 
   initializeOnReady: function () {
-    initializeLinkHints();
+    linkHints.init();
   }
 };