(function(_window){

    'use strict';

    var _skykick = {};

    var _loaded = false;

    var _configBackup = null;

    var _configMig = null;

    var _baseDomain = 'https://app.skykick.com';

    if (typeof angular != 'undefined' && angular != null) {
        _skykick.$angular = angular;
    }

    /////////////////////////////////////////////////////////
    //
    //  Public methods
    //
    /////////////////////////////////////////////////////////
    _skykick.backup = function(config){
        // Validate the configuration properties
        _validateConfig(config);

        _configBackup = config;

        // If angular is already loaded, lets get the backup code
        if(_loaded){
            _downloadProductCore('backup');
        }

        return _skykick;

    }

    _skykick.migration = function(config){

        _validateConfig(config);

        _configMig = config;

        // If angular is already loaded, lets get the migration code
        if(_loaded){
            _downloadProductCore('migration');
        }

        return _skykick;

    }

    _skykick.initialize = function (config) {
        console.log("The initialize method is deprecated.  Please use the backup or migration methods instead.")
        if (config.product == 'migration') {
            _skykick.migration(config);
        } else if(config.product == 'backup') {
            _skykick.backup(config);
        }
    }

    /*
     *  Name: getConfig
     *  Description: Getter method that provides read access to the config object for use by the product libraries
     *
     */
    _skykick.getBackupConfig = function(){
        return _configBackup;
    }

    _skykick.getMigrationConfig = function(){
        return _configMig;
    }

    _skykick.downloadScript = function (url, callback){
        var script = document.createElement('script');
        script.src = url;
        script.onload = callback;
        document.head.appendChild(script);
    }

    /////////////////////////////////////////////////////////
    //
    //  Private methods
    //
    /////////////////////////////////////////////////////////

    /*
     *  Name: downloadProductCore
     *  Description: Adds a script tag to the page which downloads the correct product and version
     *
     */
    function _downloadProductCore(product){
        var revision = '';

        if(product == 'backup') {
            var url = _baseDomain+'/js/syndication/syndication.backup' + revision + '.js';
        }else{
            var url = _baseDomain+'/js/syndication/syndication.migration' + revision + '.js';
        }

        _skykick.downloadScript(url);

    }

    /*
     *  Name: validateConfig
     *  Description: Method for ensuring our config object is valid
     */
    function _validateConfig(config){
        if(config.subscriptionId == null){
            throw new Error("Please provide a valid SubscriptionId");
        }

        // Do more?
    }

    function getNGResource(){
        try {
            // Try to get the ngResource
            angular.module('ngResource');
        }catch(e) {
            skykick.downloadScript(_baseDomain+'/scripts/angular-resource/angular-resource.min.js', finish);
        }
    }

    function init(){
        _skykick.downloadScript(_baseDomain+'/scripts/angular/angular.min.js', getNGResource);
    }

    function finish(){

        _loaded = true;

        if(_configBackup) {
            _downloadProductCore('backup');
        }

        if(_configMig) {
            _downloadProductCore('migration');
        }
    }


    // Give global access to our APIs
    _window.skykick = _skykick;

    init();


}(window));