Implement default preferences

web/preferences.js

@@ -0,0 +1,126 @@
+/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
+/* Copyright 2013 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/* globals DEFAULT_PREFERENCES, PDFJS, isLocalStorageEnabled */
+
+'use strict';
+
+//#include default_preferences.js
+
+var Preferences = (function PreferencesClosure() {
+  function Preferences() {
+    this.prefs = {};
+    this.initializedPromise = this.readFromStorage().then(function(prefObj) {
+      if (prefObj) {
+        this.prefs = prefObj;
+      }
+    }.bind(this));
+  }
+
+  Preferences.prototype = {
+    writeToStorage: function Preferences_writeToStorage(prefObj) {
+      return;
+    },
+
+    readFromStorage: function Preferences_readFromStorage() {
+      var readFromStoragePromise = new PDFJS.Promise();
+      return readFromStoragePromise;
+    },
+
+    reset: function Preferences_reset() {
+      if (this.initializedPromise.isResolved) {
+        this.prefs = {};
+        this.writeToStorage(this.prefs);
+      }
+    },
+
+    set: function Preferences_set(name, value) {
+      if (!this.initializedPromise.isResolved) {
+        return;
+      } else if (DEFAULT_PREFERENCES[name] === undefined) {
+        console.error('Preferences_set: \'' + name + '\' is undefined.');
+        return;
+      } else if (value === undefined) {
+        console.error('Preferences_set: no value is specified.');
+        return;
+      }
+      var valueType = typeof value;
+      var defaultType = typeof DEFAULT_PREFERENCES[name];
+
+      if (valueType !== defaultType) {
+        if (valueType === 'number' && defaultType === 'string') {
+          value = value.toString();
+        } else {
+          console.error('Preferences_set: \'' + value + '\' is a \"' +
+                        valueType + '\", expected a \"' + defaultType + '\".');
+          return;
+        }
+      }
+      this.prefs[name] = value;
+      this.writeToStorage(this.prefs);
+    },
+
+    get: function Preferences_get(name) {
+      var defaultPref = DEFAULT_PREFERENCES[name];
+
+      if (defaultPref === undefined) {
+        console.error('Preferences_get: \'' + name + '\' is undefined.');
+        return;
+      } else if (this.initializedPromise.isResolved) {
+        var pref = this.prefs[name];
+
+        if (pref !== undefined) {
+          return pref;
+        }
+      }
+      return defaultPref;
+    }
+  };
+
+  return Preferences;
+})();
+
+//#if B2G
+//Preferences.prototype.writeToStorage = function(prefObj) {
+//  asyncStorage.setItem('preferences', JSON.stringify(prefObj));
+//};
+//
+//Preferences.prototype.readFromStorage = function() {
+//  var readFromStoragePromise = new PDFJS.Promise();
+//  asyncStorage.getItem('preferences', function(prefString) {
+//    var readPrefs = JSON.parse(prefString);
+//    readFromStoragePromise.resolve(readPrefs);
+//  });
+//  return readFromStoragePromise;
+//};
+//#endif
+
+//#if !(FIREFOX || MOZCENTRAL || B2G)
+Preferences.prototype.writeToStorage = function(prefObj) {
+  if (isLocalStorageEnabled) {
+    localStorage.setItem('preferences', JSON.stringify(prefObj));
+  }
+};
+
+Preferences.prototype.readFromStorage = function() {
+  var readFromStoragePromise = new PDFJS.Promise();
+  if (isLocalStorageEnabled) {
+    var readPrefs = JSON.parse(localStorage.getItem('preferences'));
+    readFromStoragePromise.resolve(readPrefs);
+  }
+  return readFromStoragePromise;
+};
+//#endif