jam-cloud/app/assets/javascripts/findSession.js

(function(context,$) {

    "use strict";

    context.JK = context.JK || {};
    context.JK.FindSessionScreen = function(app) {
        var logger = context.JK.logger;
        var sessionLatency;
        var sessions = {};
        var selectors = {
            TABLE_BODY: '#findSession-tableBody'
        };

        function loadSessions() {
            $.ajax({
                type: "GET",
                url: "/api/sessions",
                success: startSessionLatencyChecks
            });
        }

        function startSessionLatencyChecks(response) {
            sessionLatency.subscribe(app.clientId, latencyResponse);
            $.each(response, function(index, session) {
                sessions[session.id] = session;
                sessionLatency.sessionPings(session);
            });
        }

        function latencyResponse(sessionId) {
            renderSession(sessionId);
        }

        /**
        * Not used normally. Allows modular unit testing
        * of the renderSession method without having to do
        * as much heavy setup.
        */
        function setSession(session) { sessions[session.id] = session; }

        /**
        * Render a single session line into the table.
        * It will be inserted at the appropriate place according to the
        * sortScore in sessionLatency.
        */
        function renderSession(sessionId) {
            var $tb = $(selectors.TABLE_BODY);
            var rowTemplate = $('#template-findSession-row').html();
            var session = sessions[sessionId];
            var latencyInfo = sessionLatency.sessionInfo(sessionId);
            var vals = {
                id: session.id,
                genres: session.genres.join (','),
                sortScore: latencyInfo.sortScore,
                participants: session.participants.length,
                description: session.description || "(No description)"
            };
            var row = context.JK.fillTemplate(rowTemplate, vals);
            var insertedEarly = false;
            $.each($('tr', $tb), function(index, nextRow) {
                var $nextRow = $(nextRow);
                var rowSortScore = parseInt($nextRow.attr('data-sortScore'), 10);
                if (vals.sortScore > rowSortScore) {
                    $nextRow.before(row);
                    insertedEarly = true;
                    return false; // break
                }
            });
            if (!(insertedEarly)) {
                return $tb.append(row);
            }
        }

        function afterShow(data) {
            var $tb = $(selectors.TABLE_BODY);
            $tb.empty();
            loadSessions();
        }

        function deleteSession(evt) {
            var sessionId = $(evt.currentTarget).attr("action-id");
            if (sessionId) {
                $.ajax({
                    type: "DELETE",
                    url: "/api/sessions/" + sessionId
                }).done(loadSessions);
            }
        }

        function events() {
            $('#findSession-tableBody').on("click", '[action="delete"]', deleteSession);
        }

        /**
        * Initialize, providing an instance of the SessionLatency class.
        */
        function initialize(_sessionLatency) {
            if (_sessionLatency) {
                sessionLatency = _sessionLatency;
            } else {
                logger.warn("No sessionLatency provided.");
            }
            var screenBindings = {
                'afterShow': afterShow
            };
            app.bindScreen('findSession', screenBindings);
            events();
        }

        this.initialize = initialize;
        this.afterShow = afterShow;
        this.renderSession = renderSession;

        // Following exposed for easier testing.
        this.setSession = setSession;
        this.selectors = selectors;

    };

 })(window,jQuery);