Better state management for passkeys.

1 files changed, 29 insertions, 27 deletions

diff --git a/content_scripts/vimium_frontend.coffee b/content_scripts/vimium_frontend.coffee
index 34473e96..d34ea761 100644
--- a/content_scripts/vimium_frontend.coffee
+++ b/content_scripts/vimium_frontend.coffee
@@ -13,7 +13,8 @@ findModeQueryHasResults = false
 findModeAnchorNode = null
 isShowingHelpDialog = false
 keyPort = null
-# Users can disable Vimium on URL patterns via the settings page.
+# Users can disable Vimium on URL patterns via the settings page.  The following two variables
+# (isEnabledForUrl and passKeys) control Vimium's enabled/disabled behaviour.
 isEnabledForUrl = true
 passKeys = null
 keyQueue = null
@@ -117,43 +118,45 @@ initializePreDomReady = ->
     getScrollPosition: -> scrollX: window.scrollX, scrollY: window.scrollY
     setScrollPosition: (request) -> setScrollPosition request.scrollX, request.scrollY
     executePageCommand: executePageCommand
-    getActiveState: -> { enabled: isEnabledForUrl }
-    disableVimium: disableVimium
+    getActiveState: -> { enabled: isEnabledForUrl, passKeys: passKeys }
+    setState: setState
     currentKeyQueue: (request) -> keyQueue = request.keyQueue
 
   chrome.runtime.onMessage.addListener (request, sender, sendResponse) ->
     # in the options page, we will receive requests from both content and background scripts. ignore those
     # from the former.
     return if sender.tab and not sender.tab.url.startsWith 'chrome-extension://'
-    return unless isEnabledForUrl or request.name == 'getActiveState'
+    return unless isEnabledForUrl or request.name == 'getActiveState' or request.name == 'setState'
     sendResponse requestHandlers[request.name](request, sender)
     # Ensure the sendResponse callback is freed.
     false
 
-#
-# This is called once the background page has told us that Vimium should be enabled for the current URL.
-#
-initializeWhenEnabled = ->
-  document.addEventListener("keydown", onKeydown, true)
-  document.addEventListener("keypress", onKeypress, true)
-  document.addEventListener("keyup", onKeyup, true)
-  document.addEventListener("focus", onFocusCapturePhase, true)
-  document.addEventListener("blur", onBlurCapturePhase, true)
-  document.addEventListener("DOMActivate", onDOMActivate, true)
-  enterInsertModeIfElementIsFocused()
+# Wrapper to install event listeners.  Syntactic sugar.
+installListener = (event, callback) -> document.addEventListener(event, callback, true)
 
 #
-# Used to disable Vimium without needing to reload the page.
-# This is called if the current page's url is blacklisted using the popup UI.
+# This is called once the background page has told us that Vimium should be enabled for the current URL.
+# We enable/disable Vimium by toggling isEnabledForUrl.  The alternative, installing or uninstalling
+# listeners, is error prone.  It's more difficult to keep track of the state.
 #
-disableVimium = ->
-  document.removeEventListener("keydown", onKeydown, true)
-  document.removeEventListener("keypress", onKeypress, true)
-  document.removeEventListener("keyup", onKeyup, true)
-  document.removeEventListener("focus", onFocusCapturePhase, true)
-  document.removeEventListener("blur", onBlurCapturePhase, true)
-  document.removeEventListener("DOMActivate", onDOMActivate, true)
-  isEnabledForUrl = false
+installedListeners = false
+initializeWhenEnabled = (newPassKeys=undefined) ->
+  isEnabledForUrl = true
+  passKeys = passKeys if typeof(newPassKeys) != 'undefined'
+  if (!installedListeners)
+    installListener "keydown", (event) -> if isEnabledForUrl then onKeydown(event) else true
+    installListener "keypress", (event) -> if isEnabledForUrl then onKeypress(event) else true
+    installListener "keyup", (event) -> if isEnabledForUrl then onKeyup(event) else true
+    installListener "focus", (event) -> if isEnabledForUrl then onFocusCapturePhase(event) else true
+    installListener "blur", (event) -> if isEnabledForUrl then onBlurCapturePhase(event)
+    installListener "DOMActivate", (event) -> if isEnabledForUrl then onDOMActivate(event)
+    enterInsertModeIfElementIsFocused()
+    installedListeners = true
+
+setState = (request) ->
+  isEnabledForUrl = request.enabled
+  passKeys = request.passKeys
+  initializeWhenEnabled(passKeys) if isEnabledForUrl and !installedListeners
 
 #
 # The backend needs to know which frame has focus.
@@ -484,8 +487,7 @@ checkIfEnabledForUrl = ->
   chrome.runtime.sendMessage { handler: "isEnabledForUrl", url: url }, (response) ->
     isEnabledForUrl = response.isEnabledForUrl
     if (isEnabledForUrl)
-      initializeWhenEnabled()
-      passKeys = response.passKeys
+      initializeWhenEnabled(response.passKeys)
     else if (HUD.isReady())
       # Quickly hide any HUD we might already be showing, e.g. if we entered insert mode on page load.
       HUD.hide()