extension/lib/commands-frame.coffee

   1 ###
   2 # Copyright Simon Lydell 2015, 2016.
   3 #
   4 # This file is part of VimFx.
   5 #
   6 # VimFx is free software: you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation, either version 3 of the License, or
   9 # (at your option) any later version.
  10 #
  11 # VimFx is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15 #
  16 # You should have received a copy of the GNU General Public License
  17 # along with VimFx.  If not, see <http://www.gnu.org/licenses/>.
  18 ###
  19
  20 # This file is the equivalent to commands.coffee, but for frame scripts,
  21 # allowing interaction with web page content. Most “commands” here have the
  22 # same name as the command in commands.coffee that calls it. There are also a
  23 # few more generalized “commands” used in more than one place.
  24
  25 hints = require('./hints')
  26 translate = require('./l10n')
  27 utils = require('./utils')
  28
  29 {isProperLink, isTextInputElement, isTypingElement, isContentEditable} = utils
  30
  31 XULDocument = Ci.nsIDOMXULDocument
  32
  33 # <http://www.w3.org/html/wg/drafts/html/master/dom.html#wai-aria>
  34 CLICKABLE_ARIA_ROLES = [
  35   'link', 'button', 'tab'
  36   'checkbox', 'radio', 'combobox', 'option', 'slider', 'textbox'
  37   'menuitem', 'menuitemcheckbox', 'menuitemradio'
  38 ]
  39
  40 commands = {}
  41
  42 commands.go_up_path = ({vim, count = 1}) ->
  43   {pathname}  = vim.content.location
  44   newPathname = pathname.replace(/// (?: /[^/]+ ){1,#{count}} /?$ ///, '')
  45   if newPathname == pathname
  46     vim.notify(translate('notification.go_up_path.limit'))
  47   else
  48     vim.content.location.pathname = newPathname
  49
  50 commands.go_to_root = ({vim}) ->
  51   # `.origin` is `'null'` (as a string) on `about:` pages.
  52   if "#{vim.content.location.origin}/" in [vim.content.location.href, 'null/']
  53     vim.notify(translate('notification.go_up_path.limit'))
  54   else
  55     vim.content.location.href = vim.content.location.origin
  56
  57 commands.scroll = (args) ->
  58   {vim} = args
  59   return unless activeElement = utils.getActiveElement(vim.content)
  60   element =
  61     # If no element is focused on the page, the the active element is the
  62     # topmost `<body>`, and blurring it is a no-op. If it is scrollable, it
  63     # means that you can’t blur it in order to scroll `<html>`. Therefore it may
  64     # only be scrolled if it has been explicitly focused.
  65     if vim.state.scrollableElements.has(activeElement) and
  66        (activeElement != vim.content.document.body or
  67         vim.state.explicitBodyFocus)
  68       activeElement
  69     else
  70       vim.state.scrollableElements.filterSuitableDefault()
  71   utils.scroll(element, args)
  72
  73 commands.mark_scroll_position = ({vim, keyStr, notify = true}) ->
  74   element = vim.state.scrollableElements.filterSuitableDefault()
  75   vim.state.marks[keyStr] = [element.scrollTop, element.scrollLeft]
  76   if notify
  77     vim.notify(translate('notification.mark_scroll_position.success', keyStr))
  78
  79 commands.scroll_to_mark = (args) ->
  80   {vim, amounts: keyStr} = args
  81   unless keyStr of vim.state.marks
  82     vim.notify(translate('notification.scroll_to_mark.none', keyStr))
  83     return
  84
  85   args.amounts = vim.state.marks[keyStr]
  86   element = vim.state.scrollableElements.filterSuitableDefault()
  87   utils.scroll(element, args)
  88
  89 helper_follow = ({id, combine = true}, matcher, {vim}) ->
  90   hrefs = {}
  91   vim.state.markerElements = []
  92
  93   filter = (element, getElementShape) ->
  94     {type, semantic} = matcher({vim, element, getElementShape})
  95
  96     if vim.hintMatcher
  97       {type, semantic} = vim.hintMatcher(id, element, {type, semantic})
  98
  99     return unless type
 100     shape = getElementShape(element)
 101
 102     # CodeMirror editor uses a tiny hidden textarea positioned at the caret.
 103     # Targeting those are the only reliable way of focusing CodeMirror editors,
 104     # and doing so without moving the caret.
 105     if not shape and id == 'normal' and element.nodeName == 'TEXTAREA' and
 106        element.ownerGlobal == vim.content
 107       rect = element.getBoundingClientRect()
 108       # Use `.clientWidth` instead of `rect.width` because the latter includes
 109       # the width of the borders of the textarea, which are unreliable.
 110       if element.clientWidth == 1 and rect.height > 0
 111         shape = {
 112           nonCoveredPoint: {
 113             x: rect.left
 114             y: rect.top + rect.height / 2
 115             offset: {left: 0, top: 0}
 116           }
 117           area: rect.width * rect.height
 118         }
 119
 120     return unless shape
 121
 122     originalRect = element.getBoundingClientRect()
 123     length = vim.state.markerElements.push({element, originalRect})
 124     wrapper = {type, semantic, shape, elementIndex: length - 1}
 125
 126     if wrapper.type == 'link'
 127       {href} = element
 128       wrapper.href = href
 129
 130       # Combine links with the same href.
 131       if combine and wrapper.type == 'link' and
 132          # If the element has an 'onclick' attribute we cannot be sure that all
 133          # links with this href actually do the same thing. On some pages, such
 134          # as startpage.com, actual proper links have the 'onclick' attribute,
 135          # so we can’t exclude such links in `utils.isProperLink`.
 136          not element.hasAttribute('onclick') and
 137          # GitHub’s diff expansion buttons are links with both `href` and
 138          # `data-url`. They are JavaScript-powered using the latter attribute.
 139          not element.hasAttribute('data-url')
 140         if href of hrefs
 141           parent = hrefs[href]
 142           wrapper.parentIndex = parent.elementIndex
 143           parent.shape.area += wrapper.shape.area
 144           parent.numChildren += 1
 145         else
 146           wrapper.numChildren = 0
 147           hrefs[href] = wrapper
 148
 149     return wrapper
 150
 151   return hints.getMarkableElementsAndViewport(vim.content, filter)
 152
 153 commands.follow = helper_follow.bind(null, {id: 'normal'},
 154   ({vim, element, getElementShape}) ->
 155     document = element.ownerDocument
 156     isXUL = (document instanceof XULDocument)
 157     type = null
 158     semantic = true
 159     switch
 160       # Bootstrap. Match these before regular links, because especially slider
 161       # “buttons” often get the same hint otherwise.
 162       when element.hasAttribute('data-toggle') or
 163            element.hasAttribute('data-dismiss') or
 164            element.hasAttribute('data-slide') or
 165            element.hasAttribute('data-slide-to')
 166         # Some elements may not be semantic, but _should be_ and still deserve a
 167         # good hint.
 168         type = 'clickable'
 169       when isProperLink(element)
 170         type = 'link'
 171       when isTypingElement(element)
 172         type = 'text'
 173       when element.getAttribute('role') in CLICKABLE_ARIA_ROLES or
 174            # <http://www.w3.org/TR/wai-aria/states_and_properties>
 175            element.hasAttribute('aria-controls') or
 176            element.hasAttribute('aria-pressed') or
 177            element.hasAttribute('aria-checked') or
 178            (element.hasAttribute('aria-haspopup') and
 179             element.getAttribute('role') != 'menu')
 180         type = 'clickable'
 181       when element.tabIndex > -1 and
 182            # Google Drive Documents. The hint for this element would cover the
 183            # real hint that allows you to focus the document to start typing.
 184            element.id != 'docs-editor' and
 185            not (isXUL and element.localName.endsWith('box') and
 186                 element.localName != 'checkbox')
 187         type = 'clickable'
 188         unless isXUL or element.localName in ['a', 'input', 'button']
 189           semantic = false
 190       when element != vim.state.scrollableElements.largest and
 191            vim.state.scrollableElements.has(element)
 192         type = 'scrollable'
 193       when element.hasAttribute('onclick') or
 194            element.hasAttribute('onmousedown') or
 195            element.hasAttribute('onmouseup') or
 196            element.hasAttribute('oncommand') or
 197            # Twitter.
 198            element.classList.contains('js-new-tweets-bar') or
 199            # Feedly.
 200            element.hasAttribute('data-app-action') or
 201            element.hasAttribute('data-uri') or
 202            element.hasAttribute('data-page-action') or
 203            # Google Drive Document.
 204            element.classList.contains('kix-appview-editor')
 205         type = 'clickable'
 206         semantic = false
 207       # Facebook comment fields.
 208       when element.parentElement?.classList.contains('UFIInputContainer')
 209         type = 'clickable-special'
 210       # Putting markers on `<label>` elements is generally redundant, because
 211       # its `<input>` gets one. However, some sites hide the actual `<input>`
 212       # but keeps the `<label>` to click, either for styling purposes or to keep
 213       # the `<input>` hidden until it is used. In those cases we should add a
 214       # marker for the `<label>`.
 215       when element.localName == 'label'
 216         input =
 217           if element.htmlFor
 218             document.getElementById(element.htmlFor)
 219           else
 220             element.querySelector('input, textarea, select')
 221         if input and not getElementShape(input)
 222           type = 'clickable'
 223       # Last resort checks for elements that might be clickable because of
 224       # JavaScript.
 225       when (not isXUL and
 226             # It is common to listen for clicks on `<html>` or `<body>`. Don’t
 227             # waste time on them.
 228             element not in [document.documentElement, document.body]) and
 229            (utils.includes(element.className, 'button') or
 230             utils.includes(element.getAttribute('aria-label'), 'close') or
 231             # Do this last as it’s a potentially expensive check.
 232             utils.hasEventListeners(element, 'click'))
 233         # Make a quick check for likely clickable descendants, to reduce the
 234         # number of false positives. the element might be a “button-wrapper” or
 235         # a large element with a click-tracking event listener.
 236         unless element.querySelector('a, button, input, [class*=button]')
 237           type = 'clickable'
 238           semantic = false
 239       # When viewing an image it should get a marker to toggle zoom. This is the
 240       # most unlikely rule to match, so keep it last.
 241       when document.body?.childElementCount == 1 and
 242            element.localName == 'img' and
 243            (element.classList.contains('overflowing') or
 244             element.classList.contains('shrinkToFit'))
 245         type = 'clickable'
 246     type = null if isXUL and element.classList.contains('textbox-input')
 247     return {type, semantic}
 248 )
 249
 250 commands.follow_in_tab = helper_follow.bind(null, {id: 'tab'},
 251   ({element}) ->
 252     type = if isProperLink(element) then 'link' else null
 253     return {type, semantic: true}
 254 )
 255
 256 commands.follow_copy = helper_follow.bind(null, {id: 'copy'},
 257   ({element}) ->
 258     type = switch
 259       when isProperLink(element)
 260         'link'
 261       when isContentEditable(element)
 262         'contenteditable'
 263       when isTypingElement(element)
 264         'text'
 265       else
 266         null
 267     return {type, semantic: true}
 268 )
 269
 270 commands.follow_focus = helper_follow.bind(null, {id: 'focus', combine: false},
 271   ({vim, element}) ->
 272     type = switch
 273       when element.tabIndex > -1
 274         'focusable'
 275       when element != vim.state.scrollableElements.largest and
 276            vim.state.scrollableElements.has(element)
 277         'scrollable'
 278       else
 279         null
 280     return {type, semantic: true}
 281 )
 282
 283 commands.focus_marker_element = ({vim, elementIndex, options}) ->
 284   {element} = vim.state.markerElements[elementIndex]
 285   # To be able to focus scrollable elements, `FLAG_BYKEY` _has_ to be used.
 286   options.flag = 'FLAG_BYKEY' if vim.state.scrollableElements.has(element)
 287   utils.focusElement(element, options)
 288   vim.clearHover()
 289   vim.setHover(element)
 290
 291 commands.click_marker_element = (args) ->
 292   {vim, elementIndex, type, preventTargetBlank} = args
 293   {element} = vim.state.markerElements[elementIndex]
 294   if element.target == '_blank' and preventTargetBlank
 295     targetReset = element.target
 296     element.target = ''
 297   if type == 'clickable-special'
 298     element.click()
 299   else
 300     utils.simulateMouseEvents(element, 'click')
 301   element.target = targetReset if targetReset
 302
 303 commands.copy_marker_element = ({vim, elementIndex, property}) ->
 304   {element} = vim.state.markerElements[elementIndex]
 305   utils.writeToClipboard(element[property])
 306
 307 commands.follow_pattern = ({vim, type, options}) ->
 308   {document} = vim.content
 309
 310   # If there’s a `<link rel=prev/next>` element we use that.
 311   for link in document.head?.getElementsByTagName('link')
 312     # Also support `rel=previous`, just like Google.
 313     if type == link.rel.toLowerCase().replace(/^previous$/, 'prev')
 314       vim.content.location.href = link.href
 315       return
 316
 317   # Otherwise we look for a link or button on the page that seems to go to the
 318   # previous or next page.
 319   candidates = document.querySelectorAll(options.pattern_selector)
 320
 321   # Note: Earlier patterns should be favored.
 322   {patterns} = options
 323
 324   # Search for the prev/next patterns in the following attributes of the
 325   # element. `rel` should be kept as the first attribute, since the standard way
 326   # of marking up prev/next links (`rel="prev"` and `rel="next"`) should be
 327   # favored. Even though some of these attributes only allow a fixed set of
 328   # keywords, we pattern-match them anyways since lots of sites don’t follow the
 329   # spec and use the attributes arbitrarily.
 330   attrs = options.pattern_attrs
 331
 332   matchingLink = do ->
 333     # First search in attributes (favoring earlier attributes) as it's likely
 334     # that they are more specific than text contexts.
 335     for attr in attrs
 336       for regex in patterns
 337         for element in candidates
 338           return element if regex.test(element.getAttribute(attr))
 339
 340     # Then search in element contents.
 341     for regex in patterns
 342       for element in candidates
 343         return element if regex.test(element.textContent)
 344
 345     return null
 346
 347   if matchingLink
 348     utils.simulateMouseEvents(matchingLink, 'click')
 349     # When you go to the next page of GitHub’s code search results, the page is
 350     # loaded with AJAX. GitHub then annoyingly focuses its search input. This
 351     # autofocus cannot be prevented in a reliable way, because the case is
 352     # indistinguishable from a button whose job is to focus some text input.
 353     # However, in this command we know for sure that we can prevent the next
 354     # focus. This must be done _after_ the click has been triggered, since
 355     # clicks count as page interactions.
 356     vim.markPageInteraction(false)
 357   else
 358     vim.notify(translate("notification.follow_#{type}.none"))
 359
 360 commands.focus_text_input = ({vim, count = null}) ->
 361   {lastFocusedTextInput} = vim.state
 362   candidates = utils.querySelectorAllDeep(
 363     vim.content, 'input, textarea, [contenteditable]'
 364   )
 365   inputs = Array.filter(candidates, (element) ->
 366     return isTextInputElement(element) and utils.area(element) > 0
 367   )
 368   if lastFocusedTextInput and lastFocusedTextInput not in inputs
 369     inputs.push(lastFocusedTextInput)
 370   inputs.sort((a, b) -> a.tabIndex - b.tabIndex)
 371
 372   if inputs.length == 0
 373     vim.notify(translate('notification.focus_text_input.none'))
 374     return
 375
 376   num = switch
 377     when count?
 378       count
 379     when lastFocusedTextInput
 380       inputs.indexOf(lastFocusedTextInput) + 1
 381     else
 382       1
 383   index = Math.min(num, inputs.length) - 1
 384   select = (count? or not vim.state.hasFocusedTextInput)
 385   utils.focusElement(inputs[index], {select})
 386   vim.state.inputs = inputs
 387
 388 commands.clear_inputs = ({vim}) ->
 389   vim.state.inputs = null
 390
 391 commands.move_focus = ({vim, direction}) ->
 392   return false unless vim.state.inputs
 393   index = vim.state.inputs.indexOf(utils.getActiveElement(vim.content))
 394   # If there’s only one input, `<tab>` would cycle to itself, making it feel
 395   # like `<tab>` was not working. Then it’s better to let `<tab>` work as it
 396   # usually does.
 397   if index == -1 or vim.state.inputs.length <= 1
 398     vim.state.inputs = null
 399     return false
 400   else
 401     {inputs} = vim.state
 402     nextInput = inputs[(index + direction) %% inputs.length]
 403     utils.focusElement(nextInput, {select: true})
 404     return true
 405
 406 commands.esc = (args) ->
 407   {vim} = args
 408   commands.blur_active_element(args)
 409   vim.clearHover()
 410
 411   {document} = vim.content
 412   if document.exitFullscreen
 413     document.exitFullscreen()
 414   else
 415     document.mozCancelFullScreen()
 416
 417 commands.blur_active_element = ({vim}) ->
 418   vim.state.explicitBodyFocus = false
 419   utils.blurActiveElement(vim.content)
 420
 421 module.exports = commands