/* Baby Buddy Dashboard
 *
 * Provides a "watch" function to update the dashboard at one minute intervals
 * and/or on visibility state changes.
 */
BabyBuddy.Dashboard = function ($) {
    var runIntervalId = null;
    var dashboardElement = null;
    var hidden = null;

    var Dashboard = {
        watch: function(element_id, refresh_rate) {
            dashboardElement = $('#' + element_id);

            if (dashboardElement.length == 0) {
                console.error('Baby Buddy: Dashboard element not found.');
                return false;
            }

            if (typeof document.hidden !== "undefined") {
                hidden = "hidden";
            }
            else if (typeof document.msHidden !== "undefined") {
                hidden = "msHidden";
            }
            else if (typeof document.webkitHidden !== "undefined") {
                hidden = "webkitHidden";
            }

            if (typeof window.addEventListener === "undefined" || typeof document.hidden === "undefined") {
                if (refresh_rate) {
                    runIntervalId = setInterval(this.update, refresh_rate);
                }
            }
            else {
                window.addEventListener('focus', Dashboard.handleVisibilityChange, false);
                if (refresh_rate) {
                    runIntervalId = setInterval(Dashboard.handleVisibilityChange, refresh_rate);
                }
            }
        },

        handleVisibilityChange: function() {
            if (!document[hidden]) {
                Dashboard.update();
            }
        },

        update: function() {
            // TODO: Someday maybe update in place?
            location.reload();
        }
    };

    return Dashboard;
}(jQuery);