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 # This file contains lots of different helper functions.
  23
  24 HTMLAnchorElement   = Ci.nsIDOMHTMLAnchorElement
  25 HTMLButtonElement   = Ci.nsIDOMHTMLButtonElement
  26 HTMLInputElement    = Ci.nsIDOMHTMLInputElement
  27 HTMLTextAreaElement = Ci.nsIDOMHTMLTextAreaElement
  28 HTMLSelectElement   = Ci.nsIDOMHTMLSelectElement
  29 HTMLFrameElement    = Ci.nsIDOMHTMLFrameElement
  30 HTMLIFrameElement   = Ci.nsIDOMHTMLIFrameElement
  31 XULDocument         = Ci.nsIDOMXULDocument
  32 XULButtonElement    = Ci.nsIDOMXULButtonElement
  33 XULControlElement   = Ci.nsIDOMXULControlElement
  34 XULMenuListElement  = Ci.nsIDOMXULMenuListElement
  35 XULTextBoxElement   = Ci.nsIDOMXULTextBoxElement
  36
  37 USE_CAPTURE = true
  38
  39
  40
  41 # Element classification helpers
  42
  43 isActivatable = (element) ->
  44   return element instanceof HTMLAnchorElement or
  45          element instanceof HTMLButtonElement or
  46          (element instanceof HTMLInputElement and element.type in [
  47            'button', 'submit', 'reset', 'image'
  48          ]) or
  49          element instanceof XULButtonElement
  50
  51 isAdjustable = (element) ->
  52   return element instanceof HTMLInputElement and element.type in [
  53            'checkbox', 'radio', 'file', 'color'
  54            'date', 'time', 'datetime', 'datetime-local', 'month', 'week'
  55          ] or
  56          element instanceof XULControlElement or
  57          # Youtube special case.
  58          element.classList?.contains('html5-video-player') or
  59          element.classList?.contains('ytp-button')
  60
  61 isContentEditable = (element) ->
  62   return element.isContentEditable or
  63          # `g_editable` is a non-standard attribute commonly used by Google.
  64          element.getAttribute?('g_editable') == 'true' or
  65          element.ownerDocument?.body?.getAttribute('g_editable') == 'true'
  66
  67 isProperLink = (element) ->
  68   # `.getAttribute` is used below instead of `.hasAttribute` to exclude `<a
  69   # href="">`s used as buttons on some sites.
  70   return element.getAttribute('href') and
  71          (element instanceof HTMLAnchorElement or
  72           element.ownerDocument instanceof XULDocument) and
  73          not element.href.endsWith('#') and
  74          not element.href.startsWith('javascript:')
  75
  76 isTextInputElement = (element) ->
  77   return (element instanceof HTMLInputElement and element.type in [
  78            'text', 'search', 'tel', 'url', 'email', 'password', 'number'
  79          ]) or
  80          element instanceof HTMLTextAreaElement or
  81          # `<select>` elements can also receive text input: You may type the
  82          # text of an item to select it.
  83          element instanceof HTMLSelectElement or
  84          element instanceof XULMenuListElement or
  85          element instanceof XULTextBoxElement
  86
  87
  88
  89 # Active/focused element helpers
  90
  91 getActiveElement = (window) ->
  92   { activeElement } = window.document
  93   if activeElement instanceof HTMLFrameElement or
  94      activeElement instanceof HTMLIFrameElement
  95     return getActiveElement(activeElement.contentWindow)
  96   else
  97     return activeElement
  98
  99 blurActiveElement = (window) ->
 100   # Only blur focusable elements, in order to interfere with the browser as
 101   # little as possible.
 102   activeElement = getActiveElement(window)
 103   if activeElement and activeElement.tabIndex > -1
 104     activeElement.blur()
 105
 106 blurActiveBrowserElement = (window) ->
 107   # - Some browser UI elements, such as the web console, are not marked as
 108   #   focusable, so we can’t check if the element is focusable as in
 109   #   `blurActiveElement`.
 110   # - Blurring in the next tick allows to pass `<escape>` to the location bar to
 111   #   reset it, for example.
 112   # - Focusing the current browser afterwards allows to pass `<escape>` as well
 113   #   as unbound keys to the page.
 114   activeElement = getActiveElement(window)
 115   callback = ->
 116     activeElement.blur()
 117     window.gBrowser.selectedBrowser.focus()
 118   window.setTimeout(callback, 0)
 119
 120 # Focus an element and tell Firefox that the focus happened because of a user
 121 # keypress (not just because some random programmatic focus).
 122 focusElement = (element, options = {}) ->
 123   focusManager = Cc['@mozilla.org/focus-manager;1']
 124     .getService(Ci.nsIFocusManager)
 125   focusManager.setFocus(element, focusManager.FLAG_BYKEY)
 126   element.select?() if options.select
 127
 128 getFocusType = (event) ->
 129   target = event.originalTarget
 130   return switch
 131     when isTextInputElement(target) or isContentEditable(target)
 132       'editable'
 133     when isActivatable(target)
 134       'activatable'
 135     when isAdjustable(target)
 136       'adjustable'
 137     else
 138       null
 139
 140
 141
 142 # Event helpers
 143
 144 listen = (element, eventName, listener) ->
 145   element.addEventListener(eventName, listener, USE_CAPTURE)
 146   module.onShutdown(->
 147     element.removeEventListener(eventName, listener, USE_CAPTURE)
 148   )
 149
 150 listenOnce = (element, eventName, listener) ->
 151   fn = (event) ->
 152     listener(event)
 153     element.removeEventListener(eventName, fn, USE_CAPTURE)
 154   listen(element, eventName, fn)
 155
 156 suppressEvent = (event) ->
 157   event.preventDefault()
 158   event.stopPropagation()
 159
 160 # Simulate mouse click with a full chain of events. ('command' is for XUL
 161 # elements.)
 162 eventSequence = ['mouseover', 'mousedown', 'mouseup', 'click', 'command']
 163 simulateClick = (element) ->
 164   window = element.ownerDocument.defaultView
 165   simulatedEvents = {}
 166   for type in eventSequence
 167     mouseEvent = new window.MouseEvent(type, {
 168       # Let the event bubble in order to trigger delegated event listeners.
 169       bubbles: true
 170       # Make the event cancelable so that `<a href="#">` can be used as a
 171       # JavaScript-powered button without scrolling to the top of the page.
 172       cancelable: true
 173     })
 174     element.dispatchEvent(mouseEvent)
 175     simulatedEvents[type] = mouseEvent
 176   return simulatedEvents
 177
 178
 179
 180 # DOM helpers
 181
 182 area = (element) ->
 183   return element.clientWidth * element.clientHeight
 184
 185 createBox = (document, className, parent = null, text = null) ->
 186   box = document.createElement('box')
 187   box.className = className
 188   box.textContent = text if text?
 189   parent.appendChild(box) if parent?
 190   return box
 191
 192 insertText = (input, value) ->
 193   { selectionStart, selectionEnd } = input
 194   input.value =
 195     input.value[0...selectionStart] + value + input.value[selectionEnd..]
 196   input.selectionStart = input.selectionEnd = selectionStart + value.length
 197
 198 setAttributes = (element, attributes) ->
 199   for attribute, value of attributes
 200     element.setAttribute(attribute, value)
 201   return
 202
 203
 204
 205 # Language helpers
 206
 207 class Counter
 208   constructor: ({ start: @value = 0, @step = 1 }) ->
 209   tick: -> @value += @step
 210
 211 class EventEmitter
 212   constructor: ->
 213     @listeners = {}
 214
 215   on: (event, listener) ->
 216     (@listeners[event] ?= []).push(listener)
 217
 218   emit: (event, data) ->
 219     for listener in @listeners[event] ? []
 220       listener(data)
 221     return
 222
 223 has = Function::call.bind(Object::hasOwnProperty)
 224
 225 regexEscape = (s) -> s.replace(/[|\\{}()[\]^$+*?.]/g, '\\$&')
 226
 227 removeDuplicates = (array) ->
 228   # coffeelint: disable=no_backticks
 229   return `[...new Set(array)]`
 230   # coffeelint: enable=no_backticks
 231
 232 # Remove duplicate characters from string (case insensitive).
 233 removeDuplicateCharacters = (str) ->
 234   return removeDuplicates( str.toLowerCase().split('') ).join('')
 235
 236
 237
 238 # Misc helpers
 239
 240 formatError = (error) ->
 241   stack = String(error.stack?.formattedStack ? error.stack ? '')
 242     .split('\n')
 243     .filter((line) -> line.includes('.xpi!'))
 244     .map((line) -> '  ' + line.replace(/(?:\/<)*@.+\.xpi!/g, '@'))
 245     .join('\n')
 246   return "#{ error }\n#{ stack }"
 247
 248 getCurrentLocation = ->
 249   window = getCurrentWindow()
 250   return new window.URL(window.gBrowser.selectedBrowser.currentURI.spec)
 251
 252 getCurrentWindow = ->
 253   windowMediator = Cc['@mozilla.org/appshell/window-mediator;1']
 254     .getService(Components.interfaces.nsIWindowMediator)
 255   return windowMediator.getMostRecentWindow('navigator:browser')
 256
 257 loadCss = (name) ->
 258   sss = Cc['@mozilla.org/content/style-sheet-service;1']
 259     .getService(Ci.nsIStyleSheetService)
 260   uri = Services.io.newURI("chrome://vimfx/skin/#{ name }.css", null, null)
 261   method = sss.AUTHOR_SHEET
 262   unless sss.sheetRegistered(uri, method)
 263     sss.loadAndRegisterSheet(uri, method)
 264   module.onShutdown(->
 265     sss.unregisterSheet(uri, method)
 266   )
 267
 268 observe = (topic, observer) ->
 269   observer = {observe: observer} if typeof observer == 'function'
 270   Services.obs.addObserver(observer, topic, false)
 271   module.onShutdown(->
 272     Services.obs.removeObserver(observer, topic, false)
 273   )
 274
 275 openTab = (window, url, options) ->
 276   { gBrowser } = window
 277   window.TreeStyleTabService?.readyToOpenChildTab(gBrowser.selectedTab)
 278   gBrowser.loadOneTab(url, options)
 279
 280 # Executes `fn` and measures how much time it took.
 281 timeIt = (fn, name) ->
 282   console.time(name)
 283   result = fn()
 284   console.timeEnd(name)
 285   return result
 286
 287 writeToClipboard = (text) ->
 288   clipboardHelper = Cc['@mozilla.org/widget/clipboardhelper;1']
 289     .getService(Ci.nsIClipboardHelper)
 290   clipboardHelper.copyString(text)
 291
 292
 293
 294 module.exports = {
 295   isActivatable
 296   isAdjustable
 297   isContentEditable
 298   isProperLink
 299   isTextInputElement
 300
 301   getActiveElement
 302   blurActiveElement
 303   blurActiveBrowserElement
 304   focusElement
 305   getFocusType
 306
 307   listen
 308   listenOnce
 309   suppressEvent
 310   simulateClick
 311
 312   area
 313   createBox
 314   insertText
 315   setAttributes
 316
 317   Counter
 318   EventEmitter
 319   has
 320   regexEscape
 321   removeDuplicates
 322   removeDuplicateCharacters
 323
 324   formatError
 325   getCurrentLocation
 326   getCurrentWindow
 327   loadCss
 328   observe
 329   openTab
 330   timeIt
 331   writeToClipboard
 332 }