Detect and handle the case of our own typo correction extension being installed in parallel

lib/typoBootstrap.js

Index: lib/typoBootstrap.js
===================================================================
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+++ b/lib/typoBootstrap.js
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+/*
+ * This Source Code is subject to the terms of the Mozilla Public License
+ * version 2.0 (the "License"). You can obtain a copy of the License at
+ * http://mozilla.org/MPL/2.0/.
+ */
+
+/**
+ * @fileOverview Adds typo correction feature
+ */
+
+Cu.import("resource://gre/modules/AddonManager.jsm");
+
+let {TimeLine} = require("timeline");
+let {Prefs} = require("prefs");
+TimeLine.log("Done loading preferences");
+
+Cu.reportError("init");
+let urlfixerID = "{0fa2149e-bb2c-4ac2-a8d3-479599819475}";
+let isTypoCorrectionEnabled = false;
+
+function enableTypoCorrection()
+{
+  Cu.reportError("enable");
+  if (isTypoCorrectionEnabled)
+    return;
+  
+  require("typoFixer").attachWindowObserver();
+  isTypoCorrectionEnabled = true;
+}
+
+function disableTypoCorrection()
+{
+  Cu.reportError("disable");
+  if (!isTypoCorrectionEnabled)
+    return;
+  
+  require("typoFixer").detachWindowObserver();
+  isTypoCorrectionEnabled = false;
+}
+
+/*

[Wladimir Palant, 2012/11/19 13:49:45]

Debug code?

+function checkAddonStatusAndEnable()
+{
+  Cu.reportError("check addon status and enable");
+  AddonManager.getAddonByID(urlfixerID, function(addon)
+  {
+    checkAndEnable(addon && !addon.userDisabled);
+  });
+}
+
+function checkAndEnable(isInstalledAndEnabled)
+{
+  Cu.reportError("check and enable");
+  //Cu.reportError(isInstalledAndEnabled);
+  Cu.reportError(Prefs.correctTyposAsked);
+  Cu.reportError(Prefs.correctTypos);
+  Cu.reportError(isTypoCorrectionEnabled);
+  if (isInstalledAndEnabled)
+  {
+    disableTypoCorrection();
+  }
+  else
+  {
+    if (!Prefs.correctTyposAsked || (Prefs.correctTyposAsked && Prefs.correctTypos))
+    {
+      Cu.reportError("feature enabled");
+      enableTypoCorrection();
+    }
+    else if (!isTypoCorrectionEnabled)
+    {
+      Cu.reportError("feature disabled");
+      function onPrefChange(name)
+      {
+        if (name == "correctTypos")
+        {
+          checkAddonStatusAndEnable();
+          Prefs.removeListener(onPrefChange);
+        }
+      }
+      
+      Prefs.addListener(onPrefChange);
+    }
+  }
+}
+
+let addonListener = {
+  onEnabling: function(addon, needsRestart)
+  {
+    if (addon.id == urlfixerID)
+      checkAndEnable(true);
+  },
+  onDisabled: function(addon)
+  {
+    if (addon.id == urlfixerID)
+      checkAndEnable(false);
+  },
+  onInstalling: function(addon, needsRestart)
+  {
+    if (addon.id == urlfixerID)
+      checkAndEnable(true);
+  },
+  onUninstalled: function(addon)
+  {
+    if (addon.id == urlfixerID)
+      checkAndEnable(false);
+  }
+}
+AddonManager.addAddonListener(addonListener);
+
+checkAddonStatusAndEnable();
+*/
+
+let addonListener = null;
+function checkAndEnable(isInstalledAndEnabled)
+{
+  if (!Prefs.correctTyposAsked || (Prefs.correctTyposAsked && Prefs.correctTypos))
+  {
+    Cu.reportError("feature enabled");
+    Cu.reportError("check addon status and enable");
+    
+    if (typeof isInstalledAndEnabled == "undefined")
+    {
+      // must not be executed for addonListener because it needs to run synchronously
+      AddonManager.getAddonByID(urlfixerID, function(addon)
+      {
+        if (addon && !addon.userDisabled)
+          disableTypoCorrection();
+        else
+          enableTypoCorrection();
+      });
+    }
+    else
+    {
+      if (isInstalledAndEnabled)
+        disableTypoCorrection();
+      else
+        enableTypoCorrection();
+    }
+    
+    if (!addonListener)
+    {
+      addonListener = {
+        onEnabling: function(addon, needsRestart)
+        {
+          if (addon.id == urlfixerID)
+            checkAndEnable(true);
+        },
+        onDisabled: function(addon)
+        {
+          if (addon.id == urlfixerID)
+            checkAndEnable(false);
+        },
+        onInstalling: function(addon, needsRestart)
+        {
+          if (addon.id == urlfixerID)
+            checkAndEnable(true);
+        },
+        onUninstalled: function(addon)
+        {
+          if (addon.id == urlfixerID)
+            checkAndEnable(false);
+        }
+      }
+      AddonManager.addAddonListener(addonListener);
+    }
+  }
+  else if (!isTypoCorrectionEnabled)
+  {
+    Cu.reportError("feature disabled");
+    function onPrefChange(name)
+    {
+      if (name == "correctTypos")
+      {
+        checkAndEnable();
+        Prefs.removeListener(onPrefChange);
+      }
+    }
+    
+    Prefs.addListener(onPrefChange);
+  }
+}
+
+function checkAddonStatusAndEnable(isInstalledAndEnabled)
+{
+  if (isInstalledAndEnabled)
+    disableTypoCorrection();
+  else
+    enableTypoCorrection();
+}
+
+checkAndEnable();