Push API change proposal

/* global cordova:false */

/*!

 * Module dependencies.

 */

var exec = cordova.require('cordova/exec');

/**

 * PushNotification constructor.

 *

 * @param {Object} options to initiate Push Notifications.

 * @return {PushNotification} instance that can be monitored and cancelled.

 */

var PushNotification = function(options) {

    this._handlers = {

        'registration': [],

        'notification': [],

        'error': []

    };

    // require options parameter

    if (typeof options === 'undefined') {

        throw new Error('The options argument is required.');

    }

    // store the options to this object instance

    this.options = options;

    // triggered on registration and notification

    var that = this;

    var success = function(result) {

        if (result && typeof result.registrationId !== 'undefined') {

            that.emit('registration', result);

        } else if (result && typeof result.notification !== 'undefined') {

            that.emit('notification', result);

        }

    };

    // triggered on error

    var fail = function(msg) {

        var e = (typeof msg === 'string') ? new Error(msg) : msg;

        that.emit('error', e);

    };

    // wait at least one process tick to allow event subscriptions

    setTimeout(function() {

        exec(success, fail, 'PushNotification', 'init', [options]);

    }, 10);

};

/**

 * Listen for an event.

 *

 * The following events are supported:

 *

 *   - registration

 *   - notification

 *   - error

 *

 * @param {String} eventName to subscribe to.

 * @param {Function} callback triggered on the event.

 */

PushNotification.prototype.on = function(eventName, callback) {

    if (this._handlers.hasOwnProperty(eventName)) {

        this._handlers[eventName].push(callback);

    }

};

/**

 * Emit an event.

 *

 * This is intended for internal use only.

 *

 * @param {String} eventName is the event to trigger.

 * @param {*} all arguments are passed to the event listeners.

 *

 * @return {Boolean} is true when the event is triggered otherwise false.

 */

PushNotification.prototype.emit = function() {

    var args = Array.prototype.slice.call(arguments);

    var eventName = args.shift();

    if (!this._handlers.hasOwnProperty(eventName)) {

        return false;

    }

    for (var i = 0, length = this._handlers[eventName].length; i < length; i++) {

        this._handlers[eventName][i].apply(undefined,args);

    }

    return true;

};

/*!

 * Push Notification Plugin.

 */

module.exports = {

    /**

     * Register for Push Notifications.

     *

     * This method will instantiate a new copy of the PushNotification object

     * and start the registration process.

     *

     * @param {Object} options

     * @return {PushNotification} instance

     */

    init: function(options) {

        return new PushNotification(options);

    },

    /**

     * PushNotification Object.

     *

     * Expose the PushNotification object for direct use

     * and testing. Typically, you should use the

     * .init helper method.

     */

    PushNotification: PushNotification

};