/**
* @author Sam Mueller
* @version 0.1 
*/
(function($) {

    $.dynamicLoader = function(o) { };

    $.dynamicLoader.extend = $.extend;

    var loadUCDefaults = {
        ucName: '',
        queryString: '',
        eventBindings: {
            loaded: null, //default events
            busy: null,
            unbusy: null,
            finished: null
        }
    };

    var registeredScripts = {};

    $.dynamicLoader.extend({
        register: function(scriptUrl, onInit) {
            //only register the script if it hasn't been registered already
            if (!registeredScripts[scriptUrl]) //TODO: don't just check the dynamicLoader hash, but also check the dom for static-loaded scripts
                registeredScripts[scriptUrl] = onInit;
        },

        //right now, registerUC expects the javascript resource to share the same name as the user control
        registerUC: function(ucName, onInit) {
            var scriptUrl = ucName.toLowerCase() + '.js';
            $.dynamicLoader.register(scriptUrl, onInit);
        },

        bind: function(scriptUrl, uiCtx, eventBindings) {
            var bindAndRun = function() {
                //the script that we just received should have registered itself to the scriptloader
                //bind to all of the events
                var script = registeredScripts[scriptUrl];
                for (eventName in eventBindings) {
                    if (eventBindings[eventName]) {
                        //TODO: we need to check to make sure we don't double bind
                        if (script) {
                            $.event.add(script, eventName, function(evt) {
                                if (eventBindings[evt.type])
                                    eventBindings[evt.type](uiCtx, evt.type);
                            });
                        }
                    }
                }
                //now that we've bound to the events, we run the script
                registeredScripts[scriptUrl](uiCtx, registeredScripts[scriptUrl]);
            }

            if (!registeredScripts[scriptUrl]) {
                $.dynamicLoader.load(scriptUrl, bindAndRun);
            } else {
                //script is already loaded
                bindAndRun();
            }
        },

        load: function(scriptUrl, callback) {
            $.getScript(scriptUrl, callback); //TODO: getScript doesn't cache scripts!  write a $.getHashedScript that does this for us
        },

        loadUC: function(o) {
        var options = $.extend({}, loadUCDefaults, o || {});
        $.ajaxSetup({ cache: false });
            $.ajax({
            url: '/indoorfrontend/AjaxDynamicLoader.svc/RenderUC?path=' + options.ucName.toLowerCase() + '&' + options.queryString,
                dataType: 'html',
                success: function(data) {
                var scriptUrl = '/indoorfrontend/' + options.ucName.toLowerCase().replace('.ascx', '.js');  //js url is based on the same name and directory as the user control
                    //now bind to js (which will be dynamically loaded if it doesnt yet exist
                    var userControl = $(data);
                    $.dynamicLoader.bind(scriptUrl, userControl, options.eventBindings);
                },
                error: function showError(xhr, status, exc) {
                    //do nothing
                }
            });
            $.ajaxSetup({ cache: true });
        }
    });
})(jQuery);