add small modules for page visibility api and notification apis

www/common/notify.js

@@ -0,0 +1,100 @@
+(function () {
+    var Module = {};
+
+    var isSupported = Module.isSupported = function () {
+        return typeof(window.Notification) === 'function';
+    };
+
+    var hasPermission = Module.hasPermission = function () {
+        return Notification.permission === 'granted';
+    };
+
+    var getPermission = Module.getPermission = function (f) {
+        Notification.requestPermission(function (permission) {
+            if (permission === "granted") { f(true); }
+            else { f(false); }
+        });
+    };
+
+    var create = Module.create = function (msg, title, icon) {
+        return new Notification(title,{
+            // icon: icon,
+            body: msg,
+        });
+    };
+
+    var system = Module.system = function (msg, title, icon) {
+        // Let's check if the browser supports notifications
+        if (!isSupported()) { console.log("Notifications are not supported"); }
+
+        // Let's check whether notification permissions have already been granted
+        else if (hasPermission()) {
+            // If it's okay let's create a notification
+            return create(msg, title, icon);
+        }
+
+        // Otherwise, we need to ask the user for permission
+        else if (Notification.permission !== 'denied') {
+            getPermission(function (state) {
+                if (state) { create(msg, title, icon); }
+            });
+        }
+    };
+
+    var tab = Module.tab = function (msg, frequency, count) {
+        var original = document.title;
+        var key = '_pendingTabNotification';
+
+        var favicon = document.getElementById('favicon');
+        if (favicon) {
+            var main = favicon.getAttribute('href');
+            var alt = favicon.getAttribute('data-alt-favicon');
+        }
+
+        var cancel = function () {
+            // only run one tab notification at a time
+            if (Module[key]) {
+                window.clearInterval(Module[key]);
+                document.title = original;
+                if (favicon) {
+                    favicon.setAttribute('href', main);
+                }
+
+                return true;
+            }
+            return false;
+        };
+
+        cancel();
+
+        var step = function () {
+            document.title = (document.title === original) ? msg : original;
+            if (favicon) {
+                favicon.setAttribute('href', favicon.getAttribute('href') === main? alt : main);
+            }
+
+            --count;
+        };
+
+        Module[key] = window.setInterval(function () {
+            if (count > 0) { return step(); }
+            cancel();
+        }, frequency);
+        step();
+
+        return {
+            cancel: cancel,
+            original: original
+        };
+    };
+
+    if (typeof(module) !== 'undefined' && module.exports) {
+        module.exports = Module;
+    } else if ((typeof(define) !== 'undefined' && define !== null) && (define.amd !== null)) {
+        define(function () {
+            return Module;
+        });
+    } else {
+        window.Visible = Module;
+    }
+}());

www/common/visible.js

@@ -0,0 +1,47 @@
+(function () {
+    // Set the name of the hidden property and the change event for visibility
+    var hidden, visibilityChange; 
+    if (typeof document.hidden !== "undefined") { // Opera 12.10 and Firefox 18 and later support 
+        hidden = "hidden";
+        visibilityChange = "visibilitychange";
+    } else if (typeof document.mozHidden !== "undefined") {
+        hidden = "mozHidden";
+        visibilityChange = "mozvisibilitychange";
+    } else if (typeof document.msHidden !== "undefined") {
+        hidden = "msHidden";
+        visibilityChange = "msvisibilitychange";
+    } else if (typeof document.webkitHidden !== "undefined") {
+        hidden = "webkitHidden";
+        visibilityChange = "webkitvisibilitychange";
+    }
+
+    var Visible = {
+        hidden: hidden,
+        visibilityChange: visibilityChange,
+    };
+
+    var isSupported = Visible.isSupported = function () {
+        return !(typeof(document.addEventListener) === "undefined" ||
+            typeof document[hidden] === "undefined");
+    };
+
+    var onChange = Visible.onChange = function (f) {
+        document.addEventListener(visibilityChange, function (ev) {
+            f(!document[hidden], ev);
+        }, false);
+    };
+
+    var currently = Visible.currently = function () {
+        return !document[hidden];
+    };
+
+    if (typeof(module) !== 'undefined' && module.exports) {
+        module.exports = Visible;
+    } else if ((typeof(define) !== 'undefined' && define !== null) && (define.amd !== null)) {
+        define(function () {
+            return Visible;
+        });
+    } else {
+        window.Visible = Visible;
+    }
+}());