added Cache

WebKit/scripts/helper/CacheStorage.js

@@ -0,0 +1,64 @@
+define([
+],
+
+function() {
+
+    function CacheStorage(name) {
+        this.name = name;
+    }
+
+    CacheStorage.prototype.mkPath = function(key) {
+        return this.mkInternalPath("") + "-" + key;
+    }
+
+    CacheStorage.prototype.mkInternalPath = function(key) {
+        return "tentia-cache-" + this.name + key;
+    };
+
+    CacheStorage.prototype.getItem = function(key) {
+        return localStorage.getItem(this.mkPath(key));
+    }
+
+    CacheStorage.prototype.setItem = function(key, value) {
+        var item = this.getItem(key);
+
+        localStorage.setItem(this.mkPath(key), value);
+
+        if (!item) {
+            var length_path = this.mkInternalPath("_length");
+            var length = parseInt(localStorage.getItem(length_path), 10) + 1;
+            localStorage.setItem(length_path, length);
+        }
+    }
+
+    CacheStorage.prototype.removeItem = function(key) {
+
+        var item = this.getItem(key);
+
+        localStorage.removeItem(this.mkPath(key));
+
+        if (item) {
+            var length_path = this.mkInternalPath("_length");
+            var length = parseInt(localStorage.getItem(length_path), 10) - 1;
+            localStorage.setItem(length_path, length);
+        }
+    };
+
+    CacheStorage.prototype.clear = function() {
+        for (var i = 0; i < localStorage.length; i++) {
+            var key = localStorage.key(i);
+            if (key.startsWith(this.mkPath(""))) {
+                localStorage.removeItem(key);
+            }
+        }
+
+        localStorage.setItem(this.mkInternalPath("_length"), 0);
+    }
+
+    CacheStorage.prototype.length = function() {
+        return parseInt(localStorage.getItem(this.mkInternalPath("_length")), 10);
+    }
+
+    return CacheStorage;
+
+});