aboutsummaryrefslogtreecommitdiffstats
path: root/lib/utils.coffee
blob: d9f2d5d436f800959aab6554175585cf2dda4287 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
Utils =
  getCurrentVersion: ->
    chrome.runtime.getManifest().version

  # Takes a dot-notation object string and call the function
  # that it points to with the correct value for 'this'.
  invokeCommandString: (str, argArray) ->
    components = str.split('.')
    obj = window
    for component in components[0...-1]
      obj = obj[component]
    func = obj[components.pop()]
    func.apply(obj, argArray)

  # Creates a single DOM element from :html
  createElementFromHtml: (html) ->
    tmp = document.createElement("div")
    tmp.innerHTML = html
    tmp.firstChild

  escapeHtml: (string) -> string.replace(/</g, "&lt;").replace(/>/g, "&gt;")

  # Generates a unique ID
  createUniqueId: do ->
    id = 0
    -> id += 1

  hasChromePrefix: do ->
    chromePrefixes = [ "about:", "view-source:", "extension:", "chrome-extension:", "data:" ]
    (url) ->
      for prefix in chromePrefixes
        return true if url.startsWith prefix
      false

  hasJavascriptPrefix: (url) ->
    url.startsWith "javascript:"

  hasFullUrlPrefix: do ->
    urlPrefix = new RegExp "^[a-z]{3,}://."
    (url) -> urlPrefix.test url

  # Apply heuristics to test whether a string (such as a "javascript:" URI) has been URL encoded.
  isUrlEncoded: (string) ->
    # If it doesn't contain "%", it's not URL encoded.
    return false if -1 == string.indexOf "%"
    # If it contains certain non-URL characters, then it's not URL encoded.
    for char in [ " ", "{", "}", ";", '"', "'" ]
      return false if 0 <= string.indexOf char
    # If it contains any of these non-ascii characters, then it's not URL encoded.
    return false if /[\u0000-\u001f\u00ff-\uffff]/.test string
    # If every occurence of "%" is followed by two hexadecimal digits, then it's URL encoded (otherwise, it is
    # not).
    string.split(/%/).length == string.split(/%[0-9a-f][0-9a-f]/i).length

  # Completes a partial URL (without scheme)
  createFullUrl: (partialUrl) ->
    if @hasFullUrlPrefix(partialUrl) then partialUrl else ("http://" + partialUrl)

  # Tries to detect if :str is a valid URL.
  isUrl: (str) ->
    # Must not contain spaces
    return false if ' ' in str

    # Starts with a scheme: URL
    return true if @hasFullUrlPrefix str

    # More or less RFC compliant URL host part parsing. This should be sufficient for our needs
    urlRegex = new RegExp(
      '^(?:([^:]+)(?::([^:]+))?@)?' + # user:password (optional) => \1, \2
      '([^:]+|\\[[^\\]]+\\])'       + # host name (IPv6 addresses in square brackets allowed) => \3
      '(?::(\\d+))?$'                 # port number (optional) => \4
      )

    # Official ASCII TLDs that are longer than 3 characters + inofficial .onion TLD used by TOR
    longTlds = ['arpa', 'asia', 'coop', 'info', 'jobs', 'local', 'mobi', 'museum', 'name', 'onion']

    specialHostNames = ['localhost']

    # Try to parse the URL into its meaningful parts. If matching fails we're pretty sure that we don't have
    # some kind of URL here.
    match = urlRegex.exec (str.split '/')[0]
    return false unless match
    hostName = match[3]

    # Allow known special host names
    return true if hostName in specialHostNames

    # Allow IPv6 addresses (need to be wrapped in brackets as required by RFC). It is sufficient to check for
    # a colon, as the regex wouldn't match colons in the host name unless it's an v6 address
    return true if ':' in hostName

    # At this point we have to make a decision. As a heuristic, we check if the input has dots in it. If yes,
    # and if the last part could be a TLD, treat it as an URL
    dottedParts = hostName.split '.'

    if dottedParts.length > 1
      lastPart = dottedParts.pop()
      return true if 2 <= lastPart.length <= 3 or lastPart in longTlds

    # Allow IPv4 addresses
    return true if /^(\d{1,3}\.){3}\d{1,3}$/.test hostName

    # Fallback: no URL
    return false

  # Map a search query to its URL encoded form. The query may be either a string or an array of strings.
  # E.g. "BBC Sport" -> "BBC+Sport".
  createSearchQuery: (query) ->
    query = query.split(/\s+/) if typeof(query) == "string"
    query.map(encodeURIComponent).join "+"

  # Creates a search URL from the given :query.
  createSearchUrl: (query) ->
    # It would be better to pull the default search engine from chrome itself.  However, unfortunately chrome
    # does not provide an API for doing so.
    Settings.get("searchUrl") + @createSearchQuery query

  # Converts :string into a Google search if it's not already a URL. We don't bother with escaping characters
  # as Chrome will do that for us.
  convertToUrl: (string) ->
    string = string.trim()

    # Special-case about:[url], view-source:[url] and the like
    if Utils.hasChromePrefix string
      string
    else if Utils.hasJavascriptPrefix string
      # In some workflows, Chrome URL encodes bookmarklets.  We URL decode them, if necessary.  See #1611.
      if Utils.isUrlEncoded string then decodeURI string else string
    else if Utils.isUrl string
      Utils.createFullUrl string
    else
      Utils.createSearchUrl string

  # detects both literals and dynamically created strings
  isString: (obj) -> typeof obj == 'string' or obj instanceof String

  # Transform "zjkjkabz" into "abjkz".
  distinctCharacters: (str) ->
    unique = ""
    for char in str.split("").sort()
      unique += char unless 0 <= unique.indexOf char
    unique

  # Compares two version strings (e.g. "1.1" and "1.5") and returns
  # -1 if versionA is < versionB, 0 if they're equal, and 1 if versionA is > versionB.
  compareVersions: (versionA, versionB) ->
    versionA = versionA.split(".")
    versionB = versionB.split(".")
    for i in [0...(Math.max(versionA.length, versionB.length))]
      a = parseInt(versionA[i] || 0, 10)
      b = parseInt(versionB[i] || 0, 10)
      if (a < b)
        return -1
      else if (a > b)
        return 1
    0

  # True if the current Chrome version is at least the required version.
  haveChromeVersion: (required) ->
    chromeVersion = navigator.appVersion.match(/Chrome\/(.*?) /)?[1]
    chromeVersion and 0 <= Utils.compareVersions chromeVersion, required

  # Zip two (or more) arrays:
  #   - Utils.zip([ [a,b], [1,2] ]) returns [ [a,1], [b,2] ]
  #   - Length of result is `arrays[0].length`.
  #   - Adapted from: http://stackoverflow.com/questions/4856717/javascript-equivalent-of-pythons-zip-function
  zip: (arrays) ->
    arrays[0].map (_,i) ->
      arrays.map( (array) -> array[i] )

  # locale-sensitive uppercase detection
  hasUpperCase: (s) -> s.toLowerCase() != s

  # Give objects (including elements) distinct identities.
  getIdentity: do ->
    identities = []

    (obj) ->
      index = identities.indexOf obj
      if index < 0
        index = identities.length
        identities.push obj
      "identity-" + index

  # Return a copy of object, but with some of its properties omitted.
  copyObjectOmittingProperties: (obj, properties...) ->
    obj = extend {}, obj
    delete obj[property] for property in properties
    obj

# This creates a new function out of an existing function, where the new function takes fewer arguments. This
# allows us to pass around functions instead of functions + a partial list of arguments.
Function::curry = ->
  fixedArguments = Array.copy(arguments)
  fn = this
  -> fn.apply(this, fixedArguments.concat(Array.copy(arguments)))

Array.copy = (array) -> Array.prototype.slice.call(array, 0)

String::startsWith = (str) -> @indexOf(str) == 0

globalRoot = window ? global
globalRoot.extend = (hash1, hash2) ->
  for key of hash2
    hash1[key] = hash2[key]
  hash1

root = exports ? window
root.Utils = Utils