/* ***** BEGIN LICENSE BLOCK *****
 * Distributed under the BSD license:
 *
 * Copyright (c) 2010, Ajax.org B.V.
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of Ajax.org B.V. nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL AJAX.ORG B.V. BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * ***** END LICENSE BLOCK ***** */

/**
 * Define a module along with a payload
 * @param module a name for the payload
 * @param payload a function to call with (require, exports, module) params
 */

(function() {

var ACE_NAMESPACE = "";

var global = (function() {
    return this;
})();

// take care of the case when requirejs is used and we just need to patch it a little bit
if (!ACE_NAMESPACE && typeof requirejs !== "undefined") {

    var define = global.define;
    global.define = function(id, deps, callback) {
        if (typeof callback !== "function")
            return define.apply(this, arguments);

        return define(id, deps, function(require, exports, module) {
            if (deps[2] == "module")
                module.packaged = true;
            return callback.apply(this, arguments);
        });
    };
    global.define.packaged = true;

    return;
}


var _define = function(module, deps, payload) {
    if (typeof module !== 'string') {
        if (_define.original)
            _define.original.apply(window, arguments);
        else {
            console.error('dropping module because define wasn\'t a string.');
            console.trace();
        }
        return;
    }

    if (arguments.length == 2)
        payload = deps;

    if (!_define.modules)
        _define.modules = {};

    _define.modules[module] = payload;
};

/**
 * Get at functionality define()ed using the function above
 */
var _require = function(parentId, module, callback) {
    if (Object.prototype.toString.call(module) === "[object Array]") {
        var params = [];
        for (var i = 0, l = module.length; i < l; ++i) {
            var dep = lookup(parentId, module[i]);
            if (!dep && _require.original)
                return _require.original.apply(window, arguments);
            params.push(dep);
        }
        if (callback) {
            callback.apply(null, params);
        }
    }
    else if (typeof module === 'string') {
        var payload = lookup(parentId, module);
        if (!payload && _require.original)
            return _require.original.apply(window, arguments);

        if (callback) {
            callback();
        }

        return payload;
    }
    else {
        if (_require.original)
            return _require.original.apply(window, arguments);
    }
};

var normalizeModule = function(parentId, moduleName) {
    // normalize plugin requires
    if (moduleName.indexOf("!") !== -1) {
        var chunks = moduleName.split("!");
        return normalizeModule(parentId, chunks[0]) + "!" + normalizeModule(parentId, chunks[1]);
    }
    // normalize relative requires
    if (moduleName.charAt(0) == ".") {
        var base = parentId.split("/").slice(0, -1).join("/");
        moduleName = base + "/" + moduleName;

        while(moduleName.indexOf(".") !== -1 && previous != moduleName) {
            var previous = moduleName;
            moduleName = moduleName.replace(/\/\.\//, "/").replace(/[^\/]+\/\.\.\//, "");
        }
    }

    return moduleName;
};

/**
 * Internal function to lookup moduleNames and resolve them by calling the
 * definition function if needed.
 */
var lookup = function(parentId, moduleName) {

    moduleName = normalizeModule(parentId, moduleName);

    var module = _define.modules[moduleName];
    if (!module) {
        return null;
    }

    if (typeof module === 'function') {
        var exports = {};
        var mod = {
            id: moduleName,
            uri: '',
            exports: exports,
            packaged: true
        };

        var req = function(module, callback) {
            return _require(moduleName, module, callback);
        };

        var returnValue = module(req, exports, mod);
        exports = returnValue || mod.exports;

        // cache the resulting module object for next time
        _define.modules[moduleName] = exports;
        return exports;
    }

    return module;
};

function exportAce(ns) {
    var require = function(module, callback) {
        return _require("", module, callback);
    };    

    var root = global;
    if (ns) {
        if (!global[ns])
            global[ns] = {};
        root = global[ns];
    }

    if (!root.define || !root.define.packaged) {
        _define.original = root.define;
        root.define = _define;
        root.define.packaged = true;
    }

    if (!root.require || !root.require.packaged) {
        _require.original = root.require;
        root.require = require;
        root.require.packaged = true;
    }
}

exportAce(ACE_NAMESPACE);

})();