tguichat and tgui4.1?

tgui/packages/common/storage.js

@@ -6,71 +6,152 @@
  * @license MIT
  */
 
-export const STORAGE_NONE = 0;
-export const STORAGE_LOCAL_STORAGE = 1;
-export const STORAGE_INDEXED_DB = 2;
+export const IMPL_MEMORY = 0;
+export const IMPL_LOCAL_STORAGE = 1;
+export const IMPL_INDEXED_DB = 2;
 
-const createMock = () => {
-  let storage = {};
-  const get = key => storage[key];
-  const set = (key, value) => {
-    storage[key] = value;
-  };
-  const remove = key => {
-    storage[key] = undefined;
-  };
-  const clear = () => {
-    // NOTE: On IE8, this will probably leak memory if used often.
-    storage = {};
-  };
-  return {
-    get,
-    set,
-    remove,
-    clear,
-    engine: STORAGE_NONE,
-  };
-};
+const INDEXED_DB_VERSION = 1;
+const INDEXED_DB_NAME = 'tgui';
+const INDEXED_DB_STORE_NAME = 'storage-v1';
 
-const createLocalStorage = () => {
-  const get = key => {
-    const value = localStorage.getItem(key);
-    if (typeof value !== 'string') {
-      return;
-    }
-    return JSON.parse(value);
-  };
-  const set = (key, value) => {
-    localStorage.setItem(key, JSON.stringify(value));
-  };
-  const remove = key => {
-    localStorage.removeItem(key);
-  };
-  const clear = () => {
-    localStorage.clear();
-  };
-  return {
-    get,
-    set,
-    remove,
-    clear,
-    engine: STORAGE_LOCAL_STORAGE,
-  };
-};
+const READ_ONLY = 'readonly';
+const READ_WRITE = 'readwrite';
 
-const testLocalStorage = () => {
-  // Localstorage can sometimes throw an error, even if DOM storage is not
-  // disabled in IE11 settings.
-  // See: https://superuser.com/questions/1080011
+const testGeneric = testFn => () => {
   try {
-    return Boolean(window.localStorage && window.localStorage.getItem);
+    return Boolean(testFn());
   }
   catch {
     return false;
   }
 };
 
+// Localstorage can sometimes throw an error, even if DOM storage is not
+// disabled in IE11 settings.
+// See: https://superuser.com/questions/1080011
+const testLocalStorage = testGeneric(() => (
+  window.localStorage && window.localStorage.getItem
+));
+
+const testIndexedDb = testGeneric(() => (
+  (window.indexedDB || window.msIndexedDB)
+  && (window.IDBTransaction || window.msIDBTransaction)
+));
+
+class MemoryBackend {
+  constructor() {
+    this.impl = IMPL_MEMORY;
+    this.store = {};
+  }
+
+  async get(key) {
+    return this.store[key];
+  }
+
+  async set(key, value) {
+    this.store[key] = value;
+  }
+
+  async remove(key) {
+    this.store[key] = undefined;
+  }
+
+  async clear() {
+    this.store = {};
+  }
+}
+
+class LocalStorageBackend {
+  constructor() {
+    this.impl = IMPL_LOCAL_STORAGE;
+    this.store = {};
+  }
+
+  async get(key) {
+    const value = localStorage.getItem(key);
+    if (typeof value === 'string') {
+      return JSON.parse(value);
+    }
+  }
+
+  async set(key, value) {
+    localStorage.setItem(key, JSON.stringify(value));
+  }
+
+  async remove(key) {
+    localStorage.removeItem(key);
+  }
+
+  async clear() {
+    localStorage.clear();
+  }
+}
+
+class IndexedDbBackend {
+  constructor() {
+    this.impl = IMPL_INDEXED_DB;
+    /** @type {Promise<IDBDatabase>} */
+    this.dbPromise = new Promise((resolve, reject) => {
+      const indexedDB = window.indexedDB || window.msIndexedDB;
+      const req = indexedDB.open(INDEXED_DB_NAME, INDEXED_DB_VERSION);
+      req.onupgradeneeded = () => {
+        try {
+          req.result.createObjectStore(INDEXED_DB_STORE_NAME);
+        }
+        catch (err) {
+          reject(new Error('Failed to upgrade IDB: ' + req.error));
+        }
+      };
+      req.onsuccess = () => resolve(req.result);
+      req.onerror = () => {
+        reject(new Error('Failed to open IDB: ' + req.error));
+      };
+    });
+  }
+
+  getStore(mode) {
+    return this.dbPromise.then(db => db
+      .transaction(INDEXED_DB_STORE_NAME, mode)
+      .objectStore(INDEXED_DB_STORE_NAME));
+  }
+
+  async get(key) {
+    const store = await this.getStore(READ_ONLY);
+    return new Promise((resolve, reject) => {
+      const req = store.get(key);
+      req.onsuccess = () => resolve(req.result);
+      req.onerror = () => reject(req.error);
+    });
+  }
+
+  async set(key, value) {
+    // The reason we don't _save_ null is because IE 10 does
+    // not support saving the `null` type in IndexedDB. How
+    // ironic, given the bug below!
+    // See: https://github.com/mozilla/localForage/issues/161
+    if (value === null) {
+      value = undefined;
+    }
+    // NOTE: We deliberately make this operation transactionless
+    const store = await this.getStore(READ_WRITE);
+    store.put(value, key);
+  }
+
+  async remove(key) {
+    // NOTE: We deliberately make this operation transactionless
+    const store = await this.getStore(READ_WRITE);
+    store.delete(key);
+  }
+
+  async clear() {
+    // NOTE: We deliberately make this operation transactionless
+    const store = await this.getStore(READ_WRITE);
+    store.clear();
+  }
+}
+
 export const storage = (
-  testLocalStorage() && createLocalStorage()
-  || createMock()
+  testIndexedDb() && new IndexedDbBackend()
+  || testLocalStorage() && new LocalStorageBackend()
+  || new MemoryBackend()
 );