if (typeof(DeviceInfo) != 'object')
    DeviceInfo = {};

/**
 * This represents the PhoneGap API itself, and provides a global namespace for accessing
 * information about the state of PhoneGap.
 * @class
 */
var PhoneGap = {
    queue: {
        ready: true,
        commands: [],
        timer: null
    }
};


/**
 * Custom pub-sub channel that can have functions subscribed to it
 */
PhoneGap.Channel = function(type)
{
    this.type = type;
    this.handlers = {};
    this.guid = 0;
    this.fired = false;
    this.enabled = true;
};

/**
 * Subscribes the given function to the channel. Any time that 
 * Channel.fire is called so too will the function.
 * Optionally specify an execution context for the function
 * and a guid that can be used to stop subscribing to the channel.
 * Returns the guid.
 */
PhoneGap.Channel.prototype.subscribe = function(f, c, g) {
    // need a function to call
    if (f == null) { return; }

    var func = f;
    if (typeof c == "object" && f instanceof Function) { func = PhoneGap.close(c, f); }

    g = g || func.observer_guid || f.observer_guid || this.guid++;
    func.observer_guid = g;
    f.observer_guid = g;
    this.handlers[g] = func;
    return g;
};

/**
 * Like subscribe but the function is only called once and then it
 * auto-unsubscribes itself.
 */
PhoneGap.Channel.prototype.subscribeOnce = function(f, c) {
    var g = null;
    var _this = this;
    var m = function() {
        f.apply(c || null, arguments);
        _this.unsubscribe(g);
    }
    if (this.fired) {
	    if (typeof c == "object" && f instanceof Function) { f = PhoneGap.close(c, f); }
        f.apply(this, this.fireArgs);
    } else {
        g = this.subscribe(m);
    }
    return g;
};

/** 
 * Unsubscribes the function with the given guid from the channel.
 */
PhoneGap.Channel.prototype.unsubscribe = function(g) {
    if (g instanceof Function) { g = g.observer_guid; }
    this.handlers[g] = null;
    delete this.handlers[g];
};

/** 
 * Calls all functions subscribed to this channel.
 */
PhoneGap.Channel.prototype.fire = function(e) {
    if (this.enabled) {
        var fail = false;
        for (var item in this.handlers) {
            var handler = this.handlers[item];
            if (handler instanceof Function) {
                var rv = (handler.apply(this, arguments)==false);
                fail = fail || rv;
            }
        }
        this.fired = true;
        this.fireArgs = arguments;
        return !fail;
    }
    return true;
};

/**
 * Calls the provided function only after all of the channels specified
 * have been fired.
 */
PhoneGap.Channel.join = function(h, c) {
    var i = c.length;
    var f = function() {
        if (!(--i)) h();
    }
    for (var j=0; j<i; j++) {
        (!c[j].fired?c[j].subscribeOnce(f):i--);
    }
    if (!i) h();
};

/**
 * Boolean flag indicating if the PhoneGap API is available and initialized.
 */ // TODO: Remove this, it is unused here ... -jm
PhoneGap.available = DeviceInfo.uuid != undefined;

/**
 * Add an initialization function to a queue that ensures it will run and initialize
 * application constructors only once PhoneGap has been initialized.
 * @param {Function} func The function callback you want run once PhoneGap is initialized
 */
PhoneGap.addConstructor = function(func) {
    PhoneGap.onDeviceReady.subscribeOnce(function() {
        try {
            func();
        } catch(e) {
            if (typeof(debug['log']) == 'function') {
                debug.log("Failed to run constructor: " + debug.processMessage(e));
            } else {
                alert("Failed to run constructor: " + e.message);
            }
        }
    });
};

/**
 * Adds a plugin object to window.plugins
 */
PhoneGap.addPlugin = function(name, obj) {
	if ( !window.plugins ) {
		window.plugins = {};
	}

	if ( !window.plugins[name] ) {
		window.plugins[name] = obj;
	}
}

/**
 * onDOMContentLoaded channel is fired when the DOM content 
 * of the page has been parsed.
 */
PhoneGap.onDOMContentLoaded = new PhoneGap.Channel('onDOMContentLoaded');

/**
 * onNativeReady channel is fired when the PhoneGap native code
 * has been initialized.
 */
PhoneGap.onNativeReady = new PhoneGap.Channel('onNativeReady');

/**
 * onResume channel is fired when the PhoneGap native code
 * resumes.
 */
PhoneGap.onResume = new PhoneGap.Channel('onResume');

/**
 * onPause channel is fired when the PhoneGap native code
 * pauses.
 */
PhoneGap.onPause = new PhoneGap.Channel('onPause');

// _nativeReady is global variable that the native side can set
// to signify that the native code is ready. It is a global since 
// it may be called before any PhoneGap JS is ready.
if (typeof _nativeReady !== 'undefined') { PhoneGap.onNativeReady.fire(); }

/**
 * onDeviceReady is fired only after both onDOMContentLoaded and 
 * onNativeReady have fired.
 */
PhoneGap.onDeviceReady = new PhoneGap.Channel('onDeviceReady');

PhoneGap.onDeviceReady.subscribeOnce(function() {
    PhoneGap.JSCallback();
});

PhoneGap.Channel.join(function() {
    PhoneGap.onDeviceReady.fire();

    // Fire the onresume event, since first one happens before JavaScript is loaded
    PhoneGap.onResume.fire();
}, [ PhoneGap.onDOMContentLoaded, PhoneGap.onNativeReady ]);


// Listen for DOMContentLoaded and notify our channel subscribers
document.addEventListener('DOMContentLoaded', function() {
    PhoneGap.onDOMContentLoaded.fire();
}, false);


// Intercept calls to document.addEventListener and watch for deviceready
PhoneGap.m_document_addEventListener = document.addEventListener;

document.addEventListener = function(evt, handler, capture) {
    var e = evt.toLowerCase();
    if (e == 'deviceready') {
        PhoneGap.onDeviceReady.subscribeOnce(handler);
    } else if (e == 'resume') {
        PhoneGap.onResume.subscribe(handler);
    } else if (e == 'pause') {
        PhoneGap.onPause.subscribe(handler);
    } else {
        PhoneGap.m_document_addEventListener.call(document, evt, handler);
    }
};

/**
 * If JSON not included, use our own stringify. (Android 1.6)
 * The restriction on ours is that it must be an array of simple types.
 *
 * @param args
 * @return
 */
PhoneGap.stringify = function(args) {
    if (typeof JSON == "undefined") {
        var s = "[";
        for (var i=0; i<args.length; i++) {
            if (i > 0) {
                s = s + ",";
            }
            var type = typeof args[i];
            if ((type == "number") || (type == "boolean")) {
                s = s + args[i];
            }
            else {
                s = s + '"' + args[i] + '"';
            }
        }
        s = s + "]";
        return s;
    }
    else {
        return JSON.stringify(args);
    }
};

PhoneGap.callbackId = 0;
PhoneGap.callbacks = {};

/**
 * Execute a PhoneGap command in a queued fashion, to ensure commands do not
 * execute with any race conditions, and only run when PhoneGap is ready to
 * recieve them.
 * @param {String} command Command to be run in PhoneGap, e.g. "ClassName.method"
 * @param {String[]} [args] Zero or more arguments to pass to the method
 */
PhoneGap.exec = function(clazz, action, args) {
    try {
        var callbackId = 0;
        var r = PluginManager.exec(clazz, action, callbackId, this.stringify(args), false);
        eval("var v="+r+";");
        
        // If status is OK, then return value back to caller
        if (v.status == 0) {
            return v.message;
        }

        // If error, then display error
        else {
            console.log("Error: Status="+r.status+" Message="+v.message);
            return null;
        }
    } catch (e) {
        console.log("Error: "+e);
    }
};

PhoneGap.execAsync = function(success, fail, clazz, action, args) {
    try {
        var callbackId = clazz + PhoneGap.callbackId++;
        if (success || fail) {
            PhoneGap.callbacks[callbackId] = {success:success, fail:fail};
        }
        var r = PluginManager.exec(clazz, action, callbackId, this.stringify(args), true);
        
        // If a result was returned
        if ((typeof r == "string") && (r.length > 0)) {
            eval("var v="+r+";");
        
            // If status is OK, then return value back to caller
            if (v.status == 0) {

                // If there is a success callback, then call it now with returned value
                if (success) {
                    success(v.message);
                    delete PhoneGap.callbacks[callbackId];
                }
                return v.message;
            }

            // If error, then display error
            else {
                console.log("Error: Status="+r.status+" Message="+v.message);

                // If there is a fail callback, then call it now with returned value
                if (fail) {
                    fail(v.message);
                    delete PhoneGap.callbacks[callbackId];
                }
                return null;
            }
        }
    } catch (e) {
        console.log("Error: "+e);
    }
};

PhoneGap.callbackSuccess = function(callbackId, args) {
    if (PhoneGap.callbacks[callbackId]) {
        try {
            if (PhoneGap.callbacks[callbackId].success) {
                PhoneGap.callbacks[callbackId].success(args.message);
            }
        }
        catch (e) {
            console.log("Error in success callback: "+callbackId+" = "+e);
        }
        delete PhoneGap.callbacks[callbackId];
    }
};

PhoneGap.callbackError = function(callbackId, args) {
    if (PhoneGap.callbacks[callbackId]) {
        try {
            if (PhoneGap.callbacks[callbackId].fail) {
                PhoneGap.callbacks[callbackId].fail(args.message);
            }
        }
        catch (e) {
            console.log("Error in error callback: "+callbackId+" = "+e);
        }
        delete PhoneGap.callbacks[callbackId];
    }
};


/**
 * Internal function used to dispatch the request to PhoneGap.  It processes the
 * command queue and executes the next command on the list.  If one of the
 * arguments is a JavaScript object, it will be passed on the QueryString of the
 * url, which will be turned into a dictionary on the other end.
 * @private
 */
PhoneGap.run_command = function() {
    if (!PhoneGap.available || !PhoneGap.queue.ready)
        return;

    PhoneGap.queue.ready = false;

    var args = PhoneGap.queue.commands.shift();
    if (PhoneGap.queue.commands.length == 0) {
        clearInterval(PhoneGap.queue.timer);
        PhoneGap.queue.timer = null;
    }

    var uri = [];
    var dict = null;
    for (var i = 1; i < args.length; i++) {
        var arg = args[i];
        if (arg == undefined || arg == null)
            arg = '';
        if (typeof(arg) == 'object')
            dict = arg;
        else
            uri.push(encodeURIComponent(arg));
    }
    var url = "gap://" + args[0] + "/" + uri.join("/");
    if (dict != null) {
        var query_args = [];
        for (var name in dict) {
            if (typeof(name) != 'string')
                continue;
            query_args.push(encodeURIComponent(name) + "=" + encodeURIComponent(dict[name]));
        }
        if (query_args.length > 0)
            url += "?" + query_args.join("&");
    }
    document.location = url;

};

/**
 * Internal function that uses XHR to call into PhoneGap Java code and retrieve 
 * any JavaScript code that needs to be run.  This is used for callbacks from
 * Java to JavaScript.
 */
PhoneGap.JSCallback = function() {
    var xmlhttp = new XMLHttpRequest();

    // Callback function when XMLHttpRequest is ready
    xmlhttp.onreadystatechange=function(){
        if(xmlhttp.readyState == 4){

            // If callback has JavaScript statement to execute
            if (xmlhttp.status == 200) {

                var msg = xmlhttp.responseText;
                setTimeout(function() {
                    try {
                        var t = eval(msg);
                    }
                    catch (e) {
                        console.log("JSCallback Error: "+e);
                    }
                }, 1);
                setTimeout(PhoneGap.JSCallback, 1);
            }

            // If callback ping (used to keep XHR request from timing out)
            else if (xmlhttp.status == 404) {
                setTimeout(PhoneGap.JSCallback, 10);
            }

            // If error, restart callback server
            else {
                console.log("JSCallback Error: Request failed.");
                CallbackServer.restartServer();
                setTimeout(PhoneGap.JSCallback, 100);
            }
        }
    }

    xmlhttp.open("GET", "http://127.0.0.1:"+CallbackServer.getPort()+"/" , true);
    xmlhttp.send();
};

/**
 * Create a UUID
 *
 * @return
 */
PhoneGap.createUUID = function() {
    return PhoneGap.UUIDcreatePart(4) + '-' +
        PhoneGap.UUIDcreatePart(2) + '-' +
        PhoneGap.UUIDcreatePart(2) + '-' +
        PhoneGap.UUIDcreatePart(2) + '-' +
        PhoneGap.UUIDcreatePart(6);
};

PhoneGap.UUIDcreatePart = function(length) {
    var uuidpart = "";
    for (var i=0; i<length; i++) {
        var uuidchar = parseInt((Math.random() * 256)).toString(16);
        if (uuidchar.length == 1) {
            uuidchar = "0" + uuidchar;
        }
        uuidpart += uuidchar;
    }
    return uuidpart;
};

PhoneGap.close = function(context, func, params) {
    if (typeof params === 'undefined') {
        return function() {
            return func.apply(context, arguments);
        }
    } else {
        return function() {
            return func.apply(context, params);
        }
    }
};