/*! @license
 ==========================================================================
 SproutCore -- JavaScript Application Framework
 copyright 2006-2009, Sprout Systems Inc., Apple Inc. and contributors.

 Permission is hereby granted, free of charge, to any person obtaining a
 copy of this software and associated documentation files (the "Software"),
 to deal in the Software without restriction, including without limitation
 the rights to use, copy, modify, merge, publish, distribute, sublicense,
 and/or sell copies of the Software, and to permit persons to whom the
 Software is furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 DEALINGS IN THE SOFTWARE.

 SproutCore and the SproutCore logo are trademarks of Sprout Systems, Inc.

 For more information about SproutCore, visit http://www.sproutcore.com


 ==========================================================================
 @license */

// Most of the following code is taken from SproutCore with a few changes.

define(function (require, exports, module) {
    "use strict";

    require("./fixoldbrowsers");

    var oop = require("./oop");

    /*
     * Helper functions and hashes for key handling.
     */
    var Keys = (function () {
        var ret = {
            MODIFIER_KEYS: {
                16: 'Shift', 17: 'Ctrl', 18: 'Alt', 224: 'Meta'
            },

            KEY_MODS: {
                "ctrl": 1, "alt": 2, "option": 2, "shift": 4,
                "super": 8, "meta": 8, "command": 8, "cmd": 8
            },

            FUNCTION_KEYS: {
                8: "Backspace",
                9: "Tab",
                13: "Return",
                19: "Pause",
                27: "Esc",
                32: "Space",
                33: "PageUp",
                34: "PageDown",
                35: "End",
                36: "Home",
                37: "Left",
                38: "Up",
                39: "Right",
                40: "Down",
                44: "Print",
                45: "Insert",
                46: "Delete",
                96: "Numpad0",
                97: "Numpad1",
                98: "Numpad2",
                99: "Numpad3",
                100: "Numpad4",
                101: "Numpad5",
                102: "Numpad6",
                103: "Numpad7",
                104: "Numpad8",
                105: "Numpad9",
                '-13': "NumpadEnter",
                112: "F1",
                113: "F2",
                114: "F3",
                115: "F4",
                116: "F5",
                117: "F6",
                118: "F7",
                119: "F8",
                120: "F9",
                121: "F10",
                122: "F11",
                123: "F12",
                144: "Numlock",
                145: "Scrolllock"
            },

            PRINTABLE_KEYS: {
                32: ' ', 48: '0', 49: '1', 50: '2', 51: '3', 52: '4', 53: '5',
                54: '6', 55: '7', 56: '8', 57: '9', 59: ';', 61: '=', 65: 'a',
                66: 'b', 67: 'c', 68: 'd', 69: 'e', 70: 'f', 71: 'g', 72: 'h',
                73: 'i', 74: 'j', 75: 'k', 76: 'l', 77: 'm', 78: 'n', 79: 'o',
                80: 'p', 81: 'q', 82: 'r', 83: 's', 84: 't', 85: 'u', 86: 'v',
                87: 'w', 88: 'x', 89: 'y', 90: 'z', 107: '+', 109: '-', 110: '.',
                186: ';', 187: '=', 188: ',', 189: '-', 190: '.', 191: '/', 192: '`',
                219: '[', 220: '\\', 221: ']', 222: "'", 111: '/', 106: '*'
            }
        };

        // A reverse map of FUNCTION_KEYS
        var name, i;
        for (i in ret.FUNCTION_KEYS) {
            name = ret.FUNCTION_KEYS[i].toLowerCase();
            ret[name] = parseInt(i, 10);
        }

        // A reverse map of PRINTABLE_KEYS
        for (i in ret.PRINTABLE_KEYS) {
            name = ret.PRINTABLE_KEYS[i].toLowerCase();
            ret[name] = parseInt(i, 10);
        }

        // Add the MODIFIER_KEYS, FUNCTION_KEYS and PRINTABLE_KEYS to the KEY
        // variables as well.
        oop.mixin(ret, ret.MODIFIER_KEYS);
        oop.mixin(ret, ret.PRINTABLE_KEYS);
        oop.mixin(ret, ret.FUNCTION_KEYS);

        // aliases
        ret.enter = ret["return"];
        ret.escape = ret.esc;
        ret.del = ret["delete"];

        // workaround for firefox bug
        ret[173] = '-';

        (function () {
            var mods = ["cmd", "ctrl", "alt", "shift"];
            for (var i = Math.pow(2, mods.length); i--;) {
                ret.KEY_MODS[i] = mods.filter(function (x) {
                        return i & ret.KEY_MODS[x];
                    }).join("-") + "-";
            }
        })();

        ret.KEY_MODS[0] = "";
        ret.KEY_MODS[-1] = "input-";

        return ret;
    })();
    oop.mixin(exports, Keys);

    exports.keyCodeToString = function (keyCode) {
        // Language-switching keystroke in Chrome/Linux emits keyCode 0.
        var keyString = Keys[keyCode];
        if (typeof keyString != "string")
            keyString = String.fromCharCode(keyCode);
        return keyString.toLowerCase();
    };

});
