/**
 * Provides core functionality to Cloud9. This module sets up the plugin
 * system, event system and settings.
 *
 * @module c9.core
 * @main c9.core
 */
define(function(require, module, exports) {
    main.consumes = ["Plugin", "ext", "vfs"];
    main.provides = ["c9"];
    return main;

    function main(options, imports, register) {
        var Plugin = imports.Plugin;
        var vfs = imports.vfs;
        
        /***** Initialization *****/
        
        var plugin = new Plugin("Ajax.org", main.consumes);
        var emit = plugin.getEmitter();
        emit.setMaxListeners(500);
        
        imports.ext.vfs = imports.vfs;

        var loaded = false;
        var loggedIn = false;
        var isReady = false;
        var state = 0;
        
        var STORAGE = 1 << 1;
        var NETWORK = 1 << 2;
        var PROCESS = 1 << 3;
        var LOCAL = 1 << 4;
        
        // Copy configuration settings - To Be Deprecated!
        var skipProps = { "consumes": 1, "provides": 1, "install": 1, "name": 1 };
        for (var prop in options) {
            if (!skipProps[prop])
                plugin[prop] = options[prop];
        }
        var totalLoadTime, startLoadTime;
        
        function load() {
            if (loaded) return false;
            loaded = true;
            
            loggedIn = parseInt(plugin.uid, 10) > 0;
            
            if (vfs.connection)
                setStatus(state | STORAGE | PROCESS);
            if (vfs.connected)
                setStatus(state | NETWORK);
            if (plugin.local)
                setStatus(state | LOCAL);
    
            vfs.on("connecting", function() {
                emit("connecting");
            }, plugin);
            
            vfs.on("disconnect", function(reason) {
                setStatus(state & ~STORAGE & ~PROCESS & ~NETWORK);
                emit("disconnect");
            }, plugin);
        
            vfs.on("connect", function() {
                setStatus(state | NETWORK | STORAGE | PROCESS);
                emit("connect");
            }, plugin);
            
            vfs.on("error", function(message) {
                setStatus(state & ~STORAGE & ~PROCESS);
                // TODO: Don't display all errors?
                if (emit("showerrormessage", message) !== false) {
                    console.error(
                        "Error on server",
                        "Received following error from server:",
                        JSON.stringify(message.message)
                    );
                }
            }, plugin);
            
            vfs.on("message", function(message) {
                emit("message", message);
            }, plugin);
        
            vfs.on("away", function() {
                emit("away");
            }, plugin);
            
            vfs.on("back", function() {
                emit("back");
            }, plugin);
            
            // Before unload
            window.addEventListener("beforeunload", beforequit);
            
            // Unload
            window.addEventListener("unload", quit);
        }
        
        /***** Methods *****/

        function setStatus(s) {
            state = s;
            emit("stateChange", {state: s, last: state});
        }
        
        function has(check) {
            return (state & check) ? true : false;
        }

        function ready(){
            isReady = true;
            emit.sticky("ready");
        }
        
        function beforequit(){
            emit("beforequit");
        }
        
        function quit(){
            emit("quit");
        }
        
        function toExternalPath(path) {
            if (plugin.platform == "win32")
                path = path.replace(/^[/]+/, "").replace(/[/]+/g, "\\");
            return path;
        }
        
        function toInternalPath(path) {
            if (plugin.platform == "win32") {
                path = path.replace(/[\\/]+/g, "/");
                path = path.replace(/^\/*(\w):/, function(_, a) {
                    return "/" + a.toUpperCase() + ":";
                });
            }
            return path;
        }

        /***** Lifecycle *****/
        
        plugin.on("load", function(){
            load();
        });
        plugin.on("enable", function(){
            
        });
        plugin.on("disable", function(){
            
        });
        plugin.on("unload", function(){
            loaded = false;
        });
        
        /***** Register and define API *****/
        
        /**
         * Main c9 object for Cloud9 which holds error handlers
         * of the entire application as well as the state for availability of resources
         * @singleton
         **/
        plugin.freezePublicAPI({
             /**
              * use this constant to see if storage capabilities are currently 
              * available. This is relevant for {@link fs}.
              * 
              *   c9.has(c9.STORAGE); // Will return true if storage is available
              * 
              * @property {Number} STORAGE 
              * @readonly
              */
            STORAGE: STORAGE,
             /**
              * use this constant to see if network capabilities are currently 
              * available. This is relevant for {@link net#connect}.
              * 
              *   c9.has(c9.NETWORK); // Will return true if network is available
              * 
              * @property {Number} NETWORK
              * @readonly
              */
            NETWORK: NETWORK,
             /**
              * use this constant to see if process control capabilities are 
              * currently available. This is relevant for {@link proc#spawn}, 
              * {@link proc#execFile} and {@link proc#pty}.
              * 
              *   c9.has(c9.PROCESS); // Will return true if storage is available
              * 
              * @property {Number} PROCESS
              * @readonly
              */
            PROCESS: PROCESS,
             /**
              * use this constant to see if Cloud9 is running locally and the 
              * local runtime is available.
              * 
              *   c9.has(c9.LOCAL); // Will return true if storage is available
              * 
              * @property {Number} LOCAL
              * @readonly
              */
            LOCAL: LOCAL,
            
            /**
             * @property {String}  workspaceDir
             * @readonly
             */
            /**
             * @property {Boolean} debug        
             * @readonly
             */
            /**
             * @property {Number}  sessionId    
             * @readonly
             */
            /**
             * @property {String}  workspaceId  
             * @readonly
             */
            /**
             * @property {Boolean} readonly     
             * @readonly
             */
            /**
             * @property {String}  projectName  
             * @readonly
             */
            /**
             * @property {String}  version      
             * @readonly
             */
            /**
             * @property {Boolean} hosted       
             * @readonly
             */
            /**
             * @property {Boolean} local        
             * @readonly
             */
            
            /**
             * Specifies whether the user is logged in to Cloud9.
             * @property {Boolean} loggedIn 
             * @readonly
             */
            get loggedIn(){ return loggedIn; },
            /**
             * the connection object that manages the connection between Cloud9
             * and the workspace server. Cloud9 uses Engine.IO to manage this
             * connection.
             * @property {Object} connection 
             * @readonly
             */
            get connection(){ return vfs.connection; },
            /**
             * Specifies whether Cloud9 is connceted to the workspace server
             * @property {Boolean} connected
             * @readonly
             */
            get connected(){ return vfs.connected; },
            /**
             * a bitmask of the constants {@link c9#NETWORK}, {@link c9#STORAGE},
             * {@link c9#PROCESS}, {@link c9#LOCAL}. Use this for complex 
             * queries. 
             * See also: {@link c9#has}
             * 
             * @property {Number} status
             * @readonly
             */
            get status(){ return state; },
            /**
             * the URL from which Cloud9 is loaded.
             * @property {String} location
             * @readonly
             */
            get location(){ return location && location.href || ""; },
            /**
             * 
             */
            get totalLoadTime(){ return totalLoadTime; },
            set totalLoadTime(v){ totalLoadTime = v; },
            /**
             * 
             */
            get startLoadTime(){ return startLoadTime; },
            set startLoadTime(v){ startLoadTime = v; },
            /**
             * 
             */
            get isReady(){ return isReady; },
            
            _events: [
                /**
                 * Fires when a javascript exception occurs.
                 * @event error 
                 * @param {Object} e
                 * @param {String} e.oldpath
                 */
                "error",
                /**
                 * Fires when Cloud9 starts connecting to the workspace server.
                 * @event connecting
                 */
                "connecting",
                /**
                 * Fires when Cloud9 is connected to the workspace server.
                 * @event connect
                 */
                "connect",
                /**
                 * Fires when Cloud9 is permanently disconnected from the 
                 * workspace server.
                 * 
                 * @event disconnect
                 */
                "disconnect",
                /**
                 * Fires when Cloud9 receives a message from the workspace server.
                 * @event message
                 * @param {String} message the message that is received
                 */
                "message",
                /**
                 * Fires when Cloud9 is disconnected from the workspace server.
                 * Cloud9 will try to re-establish the connection with the server
                 * for a few minutes. When that doesn't happen the disconnect 
                 * event is fired.
                 * @event away
                 */
                "away",
                /**
                 * Fires when Cloud9 is reconnected to a pre-existing session 
                 * from which it was temporarily disconnected.
                 * @event back
                 */
                "back",
                /**
                 * Fires when there is a connection error
                 * @event showerrormessage
                 * @param {String} message the error message to display
                 */
                "showerrormessage",
                /**
                 * Fires when all plugins have loaded
                 * @event ready
                 */
                "ready",
                /**
                 * Fires just before exiting the application.
                 * @event beforequit
                 */
                "beforequit"
            ],
            
            /**
             * Send a message to the statefull server
             * @param {Object} msg the JSON to send to the client
             */
            send: vfs.send,
            
            /**
             * Sets the availability of resources. Use bitwise operations to
             * set availability of different resources. The default 
             * resources are {@link c9#NETWORK}, {@link c9#STORAGE}, 
             * {@link c9#PROCESS}, {@link c9#LOCAL}
             * @param {Number} status a bitwised & of {@link c9#NETWORK}, 
             *   {@link c9#STORAGE}, {@link c9#PROCESS}, {@link c9#LOCAL}
             */
            setStatus: setStatus,
            
            /**
             * Checks the availability of resources. Use the following constants 
             * {@link c9#NETWORK}, {@link c9#STORAGE}, {@link c9#PROCESS}, 
             * {@link c9#LOCAL}
             * @param {Number} test one of {@link c9#NETWORK}, {@link c9#STORAGE}, 
             *   {@link c9#PROCESS}, {@link c9#LOCAL}
             */
            has: has,

            /**
             * This method is called by the boot loader, it triggers the ready 
             * event.
             * 
             * @private
             */
            ready: ready,

            /**
             * This method is called before exiting cloud9.
             * 
             * @private
             */
            beforequit: beforequit,

            /**
             * This method is called to exit cloud9.
             * 
             * @private
             */
            quit: quit,
            
            /**
             * Canonicalizes a path to its internal form.
             * For example, turns C:\ into /C:/ on Windows.
             */
            toInternalPath: toInternalPath,
            
            /**
             * Canonicalizes a path to its external form.
             * For example, turns /C:/ into C:\ on Windows.
             */
            toExternalPath: toExternalPath
        });
        
        register(null, {
            c9: plugin
        });
    }
});