extension/lib/utils.coffee

   1 ###
   2 # Copyright Anton Khodakivskiy 2012, 2013, 2014.
   3 # Copyright Simon Lydell 2013, 2014.
   4 # Copyright Wang Zhuochun 2013.
   5 #
   6 # This file is part of VimFx.
   7 #
   8 # VimFx is free software: you can redistribute it and/or modify
   9 # it under the terms of the GNU General Public License as published by
  10 # the Free Software Foundation, either version 3 of the License, or
  11 # (at your option) any later version.
  12 #
  13 # VimFx is distributed in the hope that it will be useful,
  14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 # GNU General Public License for more details.
  17 #
  18 # You should have received a copy of the GNU General Public License
  19 # along with VimFx.  If not, see <http://www.gnu.org/licenses/>.
  20 ###
  21
  22 { getPref
  23 , setPref
  24 } = require('./prefs')
  25
  26 ADDON_ID = 'VimFx@akhodakivskiy.github.com'
  27
  28 { classes: Cc, interfaces: Ci, utils: Cu } = Components
  29
  30 HTMLInputElement    = Ci.nsIDOMHTMLInputElement
  31 HTMLTextAreaElement = Ci.nsIDOMHTMLTextAreaElement
  32 HTMLSelectElement   = Ci.nsIDOMHTMLSelectElement
  33 XULMenuListElement  = Ci.nsIDOMXULMenuListElement
  34 XULDocument         = Ci.nsIDOMXULDocument
  35 XULElement          = Ci.nsIDOMXULElement
  36 XPathResult         = Ci.nsIDOMXPathResult
  37 HTMLDocument        = Ci.nsIDOMHTMLDocument
  38 HTMLElement         = Ci.nsIDOMHTMLElement
  39 Window              = Ci.nsIDOMWindow
  40 ChromeWindow        = Ci.nsIDOMChromeWindow
  41
  42 class Bucket
  43   constructor: (@newFunc) ->
  44     @bucket = new WeakMap()
  45
  46   get: (obj) ->
  47     if @bucket.has(obj)
  48       return @bucket.get(obj)
  49     else
  50       return @bucket.set(obj, @newFunc(obj))
  51
  52   forget: (obj) ->
  53     @bucket.delete(obj)
  54
  55 getEventWindow = (event) ->
  56   if event.originalTarget instanceof Window
  57     return event.originalTarget
  58   else
  59     doc = event.originalTarget.ownerDocument or event.originalTarget
  60     if doc instanceof HTMLDocument or doc instanceof XULDocument
  61       return doc.defaultView
  62
  63 getEventRootWindow = (event) ->
  64   return unless window = getEventWindow(event)
  65   return getRootWindow(window)
  66
  67 getEventCurrentTabWindow = (event) ->
  68   return unless rootWindow = getEventRootWindow(event)
  69   return getCurrentTabWindow(rootWindow)
  70
  71 getRootWindow = (window) ->
  72   return window
  73     .QueryInterface(Ci.nsIInterfaceRequestor)
  74     .getInterface(Ci.nsIWebNavigation)
  75     .QueryInterface(Ci.nsIDocShellTreeItem)
  76     .rootTreeItem
  77     .QueryInterface(Ci.nsIInterfaceRequestor)
  78     .getInterface(Window)
  79
  80 getCurrentTabWindow = (window) ->
  81   return window.gBrowser.selectedTab.linkedBrowser.contentWindow
  82
  83 blurActiveElement = (window) ->
  84   # Only blur editable elements, in order to interfere with the browser as
  85   # little as possible.
  86   { activeElement } = window.document
  87   if activeElement and isElementEditable(activeElement)
  88     activeElement.blur()
  89
  90 isTextInputElement = (element) ->
  91   return element instanceof HTMLInputElement or
  92          element instanceof HTMLTextAreaElement
  93
  94 isElementEditable = (element) ->
  95   return element.isContentEditable or
  96          element instanceof HTMLInputElement or
  97          element instanceof HTMLTextAreaElement or
  98          element instanceof HTMLSelectElement or
  99          element instanceof XULMenuListElement or
 100          element.isContentEditable or
 101          isElementGoogleEditable(element)
 102
 103 isElementGoogleEditable = (element) ->
 104   # `g_editable` is a non-standard attribute commonly used by Google.
 105   return element.getAttribute?('g_editable') == 'true' or
 106          (element instanceof HTMLElement and
 107           element.ownerDocument.body?.getAttribute('g_editable') == 'true')
 108
 109 isElementVisible = (element) ->
 110   document = element.ownerDocument
 111   window   = document.defaultView
 112   computedStyle = window.getComputedStyle(element, null)
 113   return computedStyle.getPropertyValue('visibility') == 'visible' and
 114          computedStyle.getPropertyValue('display') != 'none' and
 115          computedStyle.getPropertyValue('opacity') != '0'
 116
 117 getSessionStore = ->
 118   Cc['@mozilla.org/browser/sessionstore;1'].getService(Ci.nsISessionStore)
 119
 120 loadCss = do ->
 121   sss = Cc['@mozilla.org/content/style-sheet-service;1']
 122     .getService(Ci.nsIStyleSheetService)
 123   return (name) ->
 124     uri = getResourceURI("resources/#{ name }.css")
 125     # `AGENT_SHEET` is used to override userContent.css and Stylish. Custom
 126     # website themes installed by users often make the hint markers unreadable,
 127     # for example. Just using `!important` in the CSS is not enough.
 128     unless sss.sheetRegistered(uri, sss.AGENT_SHEET)
 129       sss.loadAndRegisterSheet(uri, sss.AGENT_SHEET)
 130
 131     module.onShutdown(->
 132       sss.unregisterSheet(uri, sss.AGENT_SHEET)
 133     )
 134
 135 # Store events that we’ve simulated. A `WeakMap` is used in order not to leak
 136 # memory. This approach is better than for example setting `event.simulated =
 137 # true`, since that tells the sites that the click was simulated, and allows
 138 # sites to spoof it.
 139 simulated_events = new WeakMap()
 140
 141 # Simulate mouse click with a full chain of events.  Copied from Vimium
 142 # codebase.
 143 simulateClick = (element, modifiers = {}) ->
 144   document = element.ownerDocument
 145   window = document.defaultView
 146
 147   eventSequence = ['mouseover', 'mousedown', 'mouseup', 'click']
 148   for event in eventSequence
 149     mouseEvent = document.createEvent('MouseEvents')
 150     mouseEvent.initMouseEvent(
 151       event, true, true, window, 1, 0, 0, 0, 0,
 152       modifiers.ctrlKey, false, false, modifiers.metaKey,
 153       0, null
 154     )
 155     simulated_events.set(mouseEvent, true)
 156     # Debugging note: Firefox will not execute the element's default action if
 157     # we dispatch this click event, but Webkit will. Dispatching a click on an
 158     # input box does not seem to focus it; we do that separately.
 159     element.dispatchEvent(mouseEvent)
 160
 161 isEventSimulated = (event) ->
 162   return simulated_events.has(event)
 163
 164 WHEEL_MODE_PIXEL = Ci.nsIDOMWheelEvent.DOM_DELTA_PIXEL
 165 WHEEL_MODE_LINE  = Ci.nsIDOMWheelEvent.DOM_DELTA_LINE
 166 WHEEL_MODE_PAGE  = Ci.nsIDOMWheelEvent.DOM_DELTA_PAGE
 167
 168 # Simulate mouse scroll event by specific offsets given that mouse cursor is at
 169 # specified position.
 170 simulateWheel = (window, deltaX, deltaY, mode = WHEEL_MODE_PIXEL) ->
 171   windowUtils = window
 172     .QueryInterface(Ci.nsIInterfaceRequestor)
 173     .getInterface(Ci.nsIDOMWindowUtils)
 174
 175   [pX, pY] = [window.innerWidth / 2, window.innerHeight / 2]
 176   windowUtils.sendWheelEvent(
 177     pX, pY,             # Window offset (x, y) in pixels.
 178     deltaX, deltaY, 0,  # Deltas (x, y, z).
 179     mode,               # Mode (pixel, line, page).
 180     0,                  # Key Modifiers.
 181     0, 0,               # Line or Page deltas (x, y).
 182     0                   # Options.
 183   )
 184
 185 # Write a string to the system clipboard.
 186 writeToClipboard = (text) ->
 187   clipboardHelper = Cc['@mozilla.org/widget/clipboardhelper;1']
 188     .getService(Ci.nsIClipboardHelper)
 189   clipboardHelper.copyString(text)
 190
 191 # Read the system clipboard.
 192 readFromClipboard = (window) ->
 193   trans = Cc['@mozilla.org/widget/transferable;1']
 194     .createInstance(Ci.nsITransferable)
 195
 196   if trans.init
 197     privacyContext = window
 198       .QueryInterface(Ci.nsIInterfaceRequestor)
 199       .getInterface(Ci.nsIWebNavigation)
 200       .QueryInterface(Ci.nsILoadContext)
 201     trans.init(privacyContext)
 202
 203   trans.addDataFlavor('text/unicode')
 204
 205   clip = Cc['@mozilla.org/widget/clipboard;1'].getService(Ci.nsIClipboard)
 206   clip.getData(trans, Ci.nsIClipboard.kGlobalClipboard)
 207
 208   str = {}
 209   strLength = {}
 210
 211   trans.getTransferData('text/unicode', str, strLength)
 212
 213   if str
 214     str = str.value.QueryInterface(Ci.nsISupportsString)
 215     return str.data.substring(0, strLength.value / 2)
 216
 217   return undefined
 218
 219 # Executes function `func` and mearues how much time it took.
 220 timeIt = (func, name) ->
 221   console.time(name)
 222   result = func()
 223   console.timeEnd(name)
 224   return result
 225
 226 isBlacklisted = (str) ->
 227   matchingRules = getMatchingBlacklistRules(str)
 228   return (matchingRules.length != 0)
 229
 230 # Returns all rules in the blacklist that match the provided string.
 231 getMatchingBlacklistRules = (str) ->
 232   return getBlacklist().filter((rule) ->
 233     /// ^#{ simpleWildcards(rule) }$ ///i.test(str)
 234   )
 235
 236 getBlacklist = ->
 237   return splitListString(getPref('black_list'))
 238
 239 setBlacklist = (blacklist) ->
 240   setPref('black_list', blacklist.join(','))
 241
 242 updateBlacklist = ({ add, remove } = {}) ->
 243   blacklist = getBlacklist()
 244
 245   if add
 246     blacklist.push(splitListString(add)...)
 247
 248   blacklist = blacklist.filter((rule) -> rule != '')
 249   blacklist = removeDuplicates(blacklist)
 250
 251   if remove
 252     for rule in splitListString(remove) when rule in blacklist
 253       blacklist.splice(blacklist.indexOf(rule), 1)
 254
 255   setBlacklist(blacklist)
 256
 257 # Splits a comma/space separated list into an array.
 258 splitListString = (str) ->
 259   return str.split(/\s*,[\s,]*/)
 260
 261 # Prepares a string to be used in a regexp, where "*" matches zero or more
 262 # characters and "!" matches one character.
 263 simpleWildcards = (string) ->
 264   return regexpEscape(string).replace(/\\\*/g, '.*').replace(/!/g, '.')
 265
 266 # Returns the first element that matches a pattern, favoring earlier patterns.
 267 # The patterns are case insensitive `simpleWildcards`s and must match either in
 268 # the beginning or at the end of a string. Moreover, a pattern does not match
 269 # in the middle of words, so "previous" does not match "previously". If that is
 270 # desired, a pattern such as "previous*" can be used instead. Note: We cannot
 271 # use `\b` word boundaries, because they don’t work well with non-English
 272 # characters. Instead we match a space as word boundary. Therefore we normalize
 273 # the whitespace and add spaces at the edges of the element text.
 274 getBestPatternMatch = (patterns, attrs, elements) ->
 275   regexps = []
 276   for pattern in patterns
 277     wildcarded = simpleWildcards(pattern)
 278     regexps.push(/// ^\s(?:#{ wildcarded })\s | \s(?:#{ wildcarded })\s$ ///i)
 279
 280   # Helper function that matches a string against all the patterns.
 281   matches = (text) ->
 282     normalizedText = " #{ text } ".replace(/\s+/g, ' ')
 283     for re in regexps
 284       if re.test(normalizedText)
 285         return true
 286     return false
 287
 288   # First search in attributes (favoring earlier attributes) as it's likely
 289   # that they are more specific than text contexts.
 290   for attr in attrs
 291     for element in elements
 292       if matches(element.getAttribute(attr))
 293         return element
 294
 295   # Then search in element contents.
 296   for element in elements
 297     if matches(element.textContent)
 298       return element
 299
 300   return null
 301
 302 # Get VimFx verion. AddonManager only provides async API to access addon data,
 303 # so it's a bit tricky...
 304 getVersion = do ->
 305   version = null
 306
 307   scope = {}
 308   Cu.import('resource://gre/modules/AddonManager.jsm', scope)
 309   scope.AddonManager.getAddonByID(ADDON_ID, (addon) -> version = addon.version)
 310
 311   return ->
 312     return version
 313
 314 parseHTML = (document, html) ->
 315   parser = Cc['@mozilla.org/parserutils;1'].getService(Ci.nsIParserUtils)
 316   flags = parser.SanitizerAllowStyle
 317   return parser.parseFragment(html, flags, false, null,
 318                               document.documentElement)
 319
 320 createElement = (document, type, attributes = {}) ->
 321   element = document.createElement(type)
 322
 323   for attribute, value of attributes
 324     element.setAttribute(attribute, value)
 325
 326   if document instanceof HTMLDocument
 327     element.classList.add('VimFxReset')
 328
 329   return element
 330
 331 isURL = (str) ->
 332   try
 333     url = Cc['@mozilla.org/network/io-service;1']
 334       .getService(Ci.nsIIOService)
 335       .newURI(str, null, null)
 336       .QueryInterface(Ci.nsIURL)
 337     return true
 338   catch err
 339     return false
 340
 341 # Use Firefox services to search for a given string.
 342 browserSearchSubmission = (str) ->
 343   ss = Cc['@mozilla.org/browser/search-service;1']
 344     .getService(Ci.nsIBrowserSearchService)
 345
 346   engine = ss.currentEngine or ss.defaultEngine
 347   return engine.getSubmission(str, null)
 348
 349 # Get hint characters, convert them to lower case, and filter duplicates.
 350 getHintChars = ->
 351   hintChars = getPref('hint_chars')
 352   # Make sure that hint chars contain at least two characters.
 353   if not hintChars or hintChars.length < 2
 354     hintChars = 'fj'
 355
 356   return removeDuplicateCharacters(hintChars)
 357
 358 # Remove duplicate characters from string (case insensitive).
 359 removeDuplicateCharacters = (str) ->
 360   return removeDuplicates( str.toLowerCase().split('') ).join('')
 361
 362 # Return URI to some file in the extension packaged as resource.
 363 getResourceURI = do ->
 364   baseURI = Services.io.newURI(__SCRIPT_URI_SPEC__, null, null)
 365   return (path) -> return Services.io.newURI(path, null, baseURI)
 366
 367 # Escape a string to render it usable in regular expressions.
 368 regexpEscape = (s) -> s and s.replace(/[-\/\\^$*+?.()|[\]{}]/g, '\\$&')
 369
 370 removeDuplicates = (array) ->
 371   # coffeelint: disable=no_backticks
 372   return `[...new Set(array)]`
 373   # coffeelint: enable=no_backticks
 374
 375 # Why isn’t `a[@href]` used, when `area[@href]` is? Some sites (such as
 376 # StackExchange sites) leave out the `href` property and use the anchor as a
 377 # JavaScript-powered button (instead of just using the `button` element).
 378 ACTION_ELEMENT_TAGS = [
 379   'a'
 380   'area[@href]'
 381   'button'
 382   # When viewing an image directly, and it is larger than the viewport,
 383   # clicking it toggles zoom.
 384   'img[contains(@class, "decoded") and
 385      (contains(@class, "overflowing") or
 386      contains(@class, "shrinkToFit"))]'
 387 ]
 388
 389 ACTION_ELEMENT_PROPERTIES = [
 390   '@onclick'
 391   '@onmousedown'
 392   '@onmouseup'
 393   '@oncommand'
 394   '@role="link"'
 395   '@role="button"'
 396   'contains(@class, "button")'
 397   'contains(@class, "js-new-tweets-bar")'
 398 ]
 399
 400 EDITABLE_ELEMENT_TAGS = [
 401   'textarea'
 402   'select'
 403   'input[not(@type="hidden" or @disabled)]'
 404 ]
 405
 406 EDITABLE_ELEMENT_PROPERTIES = [
 407   '@contenteditable=""'
 408   'translate(@contenteditable, "TRUE", "true")="true"'
 409 ]
 410
 411 FOCUSABLE_ELEMENT_TAGS = [
 412   'frame'
 413   'iframe'
 414   'embed'
 415   'object'
 416 ]
 417
 418 FOCUSABLE_ELEMENT_PROPERTIES = [
 419   '@tabindex!=-1'
 420 ]
 421
 422 getMarkableElements = do ->
 423   xpathify = (tags, properties) ->
 424     return tags
 425       .concat("*[#{ properties.join(' or ') }]")
 426       .map((rule) -> "//#{ rule } | //xhtml:#{ rule }")
 427       .join(' | ')
 428
 429   xpaths =
 430     action:    xpathify(ACTION_ELEMENT_TAGS,    ACTION_ELEMENT_PROPERTIES   )
 431     editable:  xpathify(EDITABLE_ELEMENT_TAGS,  EDITABLE_ELEMENT_PROPERTIES )
 432     focusable: xpathify(FOCUSABLE_ELEMENT_TAGS, FOCUSABLE_ELEMENT_PROPERTIES)
 433     all: xpathify(
 434       # coffeelint: disable=max_line_length
 435       [ACTION_ELEMENT_TAGS...,       EDITABLE_ELEMENT_TAGS...,       FOCUSABLE_ELEMENT_TAGS...      ],
 436       [ACTION_ELEMENT_PROPERTIES..., EDITABLE_ELEMENT_PROPERTIES..., FOCUSABLE_ELEMENT_PROPERTIES...]
 437       # coffeelint: enable=max_line_length
 438     )
 439
 440   # The actual function that will return the desired elements.
 441   return (document, { type }) ->
 442     return xpathQueryAll(document, xpaths[type])
 443
 444 xpathHelper = (node, query, resultType) ->
 445   document = node.ownerDocument ? node
 446   namespaceResolver = (namespace) ->
 447     if namespace == 'xhtml' then 'http://www.w3.org/1999/xhtml' else null
 448   return document.evaluate(query, node, namespaceResolver, resultType, null)
 449
 450 xpathQuery = (node, query) ->
 451   result = xpathHelper(node, query, XPathResult.FIRST_ORDERED_NODE_TYPE)
 452   return result.singleNodeValue
 453
 454 xpathQueryAll = (node, query) ->
 455   result = xpathHelper(node, query, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE)
 456   return (result.snapshotItem(i) for i in [0...result.snapshotLength] by 1)
 457
 458
 459 exports.Bucket                    = Bucket
 460 exports.getEventWindow            = getEventWindow
 461 exports.getEventRootWindow        = getEventRootWindow
 462 exports.getEventCurrentTabWindow  = getEventCurrentTabWindow
 463 exports.getRootWindow             = getRootWindow
 464 exports.getCurrentTabWindow       = getCurrentTabWindow
 465
 466 exports.blurActiveElement         = blurActiveElement
 467 exports.isTextInputElement        = isTextInputElement
 468 exports.isElementEditable         = isElementEditable
 469 exports.isElementVisible          = isElementVisible
 470 exports.getSessionStore           = getSessionStore
 471
 472 exports.loadCss                   = loadCss
 473
 474 exports.simulateClick             = simulateClick
 475 exports.isEventSimulated          = isEventSimulated
 476 exports.simulateWheel             = simulateWheel
 477 exports.WHEEL_MODE_PIXEL          = WHEEL_MODE_PIXEL
 478 exports.WHEEL_MODE_LINE           = WHEEL_MODE_LINE
 479 exports.WHEEL_MODE_PAGE           = WHEEL_MODE_PAGE
 480 exports.readFromClipboard         = readFromClipboard
 481 exports.writeToClipboard          = writeToClipboard
 482 exports.timeIt                    = timeIt
 483
 484 exports.getMatchingBlacklistRules = getMatchingBlacklistRules
 485 exports.isBlacklisted             = isBlacklisted
 486 exports.updateBlacklist           = updateBlacklist
 487 exports.splitListString           = splitListString
 488 exports.getBestPatternMatch       = getBestPatternMatch
 489
 490 exports.getVersion                = getVersion
 491 exports.parseHTML                 = parseHTML
 492 exports.createElement             = createElement
 493 exports.isURL                     = isURL
 494 exports.browserSearchSubmission   = browserSearchSubmission
 495 exports.getHintChars              = getHintChars
 496 exports.removeDuplicates          = removeDuplicates
 497 exports.removeDuplicateCharacters = removeDuplicateCharacters
 498 exports.getResourceURI            = getResourceURI
 499 exports.getMarkableElements       = getMarkableElements
 500 exports.xpathQuery                = xpathQuery
 501 exports.xpathQueryAll             = xpathQueryAll
 502 exports.ADDON_ID                  = ADDON_ID