1 files changed, 62 insertions, 0 deletions
diff --git a/lib/keyboard_utils.coffee b/lib/keyboard_utils.coffee
new file mode 100644
index 00000000..df5bbbad
--- /dev/null
+++ b/lib/keyboard_utils.coffee
@@ -0,0 +1,62 @@
+KeyboardUtils =
+  keyCodes:
+    { ESC: 27, backspace: 8, deleteKey: 46, enter: 13, space: 32, shiftKey: 16, f1: 112, f12: 123, tab: 9 }
+
+  keyNames:
+    { 37: "left", 38: "up", 39: "right", 40: "down" }
+
+  # This is a mapping of the incorrect keyIdentifiers generated by Webkit on Windows during keydown events to
+  # the correct identifiers, which are correctly generated on Mac. We require this mapping to properly handle
+  # these keys on Windows. See https://bugs.webkit.org/show_bug.cgi?id=19906 for more details.
+  keyIdentifierCorrectionMap:
+    "U+00C0": ["U+0060", "U+007E"] # `~
+    "U+00BD": ["U+002D", "U+005F"] # -_
+    "U+00BB": ["U+003D", "U+002B"] # =+
+    "U+00DB": ["U+005B", "U+007B"] # [{
+    "U+00DD": ["U+005D", "U+007D"] # ]}
+    "U+00DC": ["U+005C", "U+007C"] # \|
+    "U+00BA": ["U+003B", "U+003A"] # ;:
+    "U+00DE": ["U+0027", "U+0022"] # '"
+    "U+00BC": ["U+002C", "U+003C"] # ,<
+    "U+00BE": ["U+002E", "U+003E"] # .>
+    "U+00BF": ["U+002F", "U+003F"] # /?
+
+  init: ->
+    if (navigator.userAgent.indexOf("Mac") != -1)
+      @platform = "Mac"
+    else if (navigator.userAgent.indexOf("Linux") != -1)
+      @platform = "Linux"
+    else
+      @platform = "Windows"
+
+  getKeyChar: (event) ->
+    # Not a letter
+    if (event.keyIdentifier.slice(0, 2) != "U+")
+      return @keyNames[event.keyCode] if (@keyNames[event.keyCode])
+      # F-key
+      if (event.keyCode >= @keyCodes.f1 && event.keyCode <= @keyCodes.f12)
+        return "f" + (1 + event.keyCode - keyCodes.f1)
+      return ""
+
+    keyIdentifier = event.keyIdentifier
+    # On Windows, the keyIdentifiers for non-letter keys are incorrect. See
+    # https://bugs.webkit.org/show_bug.cgi?id=19906 for more details.
+    if ((@platform == "Windows" || @platform == "Linux") && @keyIdentifierCorrectionMap[keyIdentifier])
+      correctedIdentifiers = @keyIdentifierCorrectionMap[keyIdentifier]
+      keyIdentifier = if event.shiftKey then correctedIdentifiers[1] else correctedIdentifiers[0]
+    unicodeKeyInHex = "0x" + keyIdentifier.substring(2)
+    character = String.fromCharCode(parseInt(unicodeKeyInHex)).toLowerCase()
+    if event.shiftKey then character.toUpperCase() else character
+
+  isPrimaryModifierKey: (event) -> if (@platform == "Mac") then event.metaKey else event.ctrlKey
+
+  isEscape: (event) ->
+    # c-[ is mapped to ESC in Vim by default.
+    (event.keyCode == @keyCodes.ESC) || (event.ctrlKey && @getKeyChar(event) == '[')
+
+KeyboardUtils.init()
+
+root = exports ? window
+root.KeyboardUtils = KeyboardUtils
+# TODO(philc): A lot of code uses this keyCodes hash... maybe we shouldn't export it as a global.
+root.keyCodes = KeyboardUtils.keyCodes