/**
 * The MIT License (MIT)
 * 
 * Copyright (c) 2014 Petka Antonov
 * 
 * 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:</p>
 * 
 * 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.
 * 
 */
var isES5 = (function(){
    "use strict";
    return this === undefined;
})();

if (isES5) {
    module.exports = {
        freeze: Object.freeze,
        defineProperty: Object.defineProperty,
        keys: Object.keys,
        getPrototypeOf: Object.getPrototypeOf,
        isArray: Array.isArray,
        isES5: isES5,
        propertyIsWritable: function(obj, prop) {
            var descriptor = Object.getOwnPropertyDescriptor(obj, prop);
            return !!(!descriptor || descriptor.writable || descriptor.set);
        }
    };
} else {
    var has = {}.hasOwnProperty;
    var str = {}.toString;
    var proto = {}.constructor.prototype;

    var ObjectKeys = function (o) {
        var ret = [];
        for (var key in o) {
            if (has.call(o, key)) {
                ret.push(key);
            }
        }
        return ret;
    }

    var ObjectDefineProperty = function (o, key, desc) {
        o[key] = desc.value;
        return o;
    }

    var ObjectFreeze = function (obj) {
        return obj;
    }

    var ObjectGetPrototypeOf = function (obj) {
        try {
            return Object(obj).constructor.prototype;
        }
        catch (e) {
            return proto;
        }
    }

    var ArrayIsArray = function (obj) {
        try {
            return str.call(obj) === "[object Array]";
        }
        catch(e) {
            return false;
        }
    }

    module.exports = {
        isArray: ArrayIsArray,
        keys: ObjectKeys,
        defineProperty: ObjectDefineProperty,
        freeze: ObjectFreeze,
        getPrototypeOf: ObjectGetPrototypeOf,
        isES5: isES5,
        propertyIsWritable: function() {
            return true;
        }
    };
}
