From: Vincent Vanwaelscappel <vincent@cubedesigners.com>
Date: Wed, 3 Jun 2015 09:32:15 +0000 (+0000)
Subject: Add storage polyfill
X-Git-Url: http://git.cubedesigners.com/?a=commitdiff_plain;h=5fd2d22827363f6b4c0c3f01254262673f45e2a9;p=fluidbook-html5.git

Add storage polyfill
---

diff --git a/js/libs/storage.js b/js/libs/storage.js
new file mode 100644
index 00000000..50f6b0f2
--- /dev/null
+++ b/js/libs/storage.js
@@ -0,0 +1,125 @@
+/**
+ * Created by Vincent on 03/06/2015.
+ */
+try {
+    // Test webstorage existence.
+    if (!window.localStorage || !window.sessionStorage) throw "exception";
+    // Test webstorage accessibility - Needed for Safari private browsing.
+    localStorage.setItem('storage_test', 1);
+    localStorage.removeItem('storage_test');
+} catch (e) {
+    (function () {
+        var Storage = function (type) {
+            function createCookie(name, value, days) {
+                var date, expires;
+
+                if (days) {
+                    date = new Date();
+                    date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
+                    expires = "; expires=" + date.toGMTString();
+                } else {
+                    expires = "";
+                }
+                document.cookie = name + "=" + value + expires + "; path=/";
+            }
+
+            function readCookie(name) {
+                var nameEQ = name + "=",
+                    ca = document.cookie.split(';'),
+                    i, c;
+
+                for (i = 0; i < ca.length; i++) {
+                    c = ca[i];
+                    while (c.charAt(0) == ' ') {
+                        c = c.substring(1, c.length);
+                        2480
+                    }
+
+                    if (c.indexOf(nameEQ) == 0) {
+                        return c.substring(nameEQ.length, c.length);
+                    }
+                }
+                return null;
+            }
+
+            function setData(data) {
+                // Convert data into JSON and encode to accommodate for special characters.
+                data = encodeURIComponent(JSON.stringify(data));
+                // Create cookie.
+                if (type == 'session') {
+                    createCookie(getSessionName(), data, 365);
+                } else {
+                    createCookie('localStorage', data, 365);
+                }
+            }
+
+            function clearData() {
+                if (type == 'session') {
+                    createCookie(getSessionName(), '', 365);
+                } else {
+                    createCookie('localStorage', '', 365);
+                }
+            }
+
+            function getData() {
+                // Get cookie data.
+                var data = type == 'session' ? readCookie(getSessionName()) : readCookie('localStorage');
+                // If we have some data decode, parse and return it.
+                return data ? JSON.parse(decodeURIComponent(data)) : {};
+            }
+
+            function getSessionName() {
+                // If there is no name for this window, set one.
+                // To ensure it's unquie use the current timestamp.
+                if (!window.name) {
+                    window.name = new Date().getTime();
+                }
+                return 'sessionStorage' + window.name;
+            }
+
+            // Initialise if there's already data.
+            var data = getData();
+
+            return {
+                length: 0,
+                clear: function () {
+                    data = {};
+                    this.length = 0;
+                    clearData();
+                },
+                getItem: function (key) {
+                    return data[key] === undefined ? null : data[key];
+                },
+                key: function (i) {
+                    // not perfect, but works
+                    var ctr = 0;
+                    for (var k in data) {
+                        if (ctr == i) return k;
+                        else ctr++;
+                    }
+                    return null;
+                },
+                removeItem: function (key) {
+                    delete data[key];
+                    this.length--;
+                    setData(data);
+                },
+                setItem: function (key, value) {
+                    data[key] = value + ''; // forces the value to a string
+                    this.length++;
+                    setData(data);
+                }
+            };
+        };
+
+        // Replace window.localStorage and window.sessionStorage with out custom
+        // implementation.
+        var localStorage = new Storage('local');
+        var sessionStorage = new Storage('session');
+        window.localStorage = localStorage;
+        window.sessionStorage = sessionStorage;
+        // For Safari private browsing need to also set the proto value.
+        window.localStorage.__proto__ = localStorage;
+        window.sessionStorage.__proto__ = sessionStorage;
+    })();
+}