DictionaryImporterMediaLoader (#1860)

* Rename param for consistency

* Move media loading functionality into DictionaryImporterMediaLoader

* Create test class for media loading

* Remove unnecessary Blob/Image/URL functionality

9 files changed, 91 insertions, 119 deletions

diff --git a/dev/database-vm.js b/dev/database-vm.js
index 07d9bd5a..ebde5a2a 100644
--- a/dev/database-vm.js
+++ b/dev/database-vm.js
@@ -30,63 +30,6 @@ const chrome = {
     }
 };
 
-class Image {
-    constructor() {
-        this._src = '';
-        this._loadCallbacks = [];
-    }
-
-    get src() {
-        return this._src;
-    }
-
-    set src(value) {
-        this._src = value;
-        this._delayTriggerLoad();
-    }
-
-    get naturalWidth() {
-        return 100;
-    }
-
-    get naturalHeight() {
-        return 100;
-    }
-
-    addEventListener(eventName, callback) {
-        if (eventName === 'load') {
-            this._loadCallbacks.push(callback);
-        }
-    }
-
-    removeEventListener(eventName, callback) {
-        if (eventName === 'load') {
-            const index = this._loadCallbacks.indexOf(callback);
-            if (index >= 0) {
-                this._loadCallbacks.splice(index, 1);
-            }
-        }
-    }
-
-    removeAttribute() {
-        // NOP
-    }
-
-    async _delayTriggerLoad() {
-        await Promise.resolve();
-        for (const callback of this._loadCallbacks) {
-            callback();
-        }
-    }
-}
-
-class Blob {
-    constructor(array, options) {
-        this._array = array;
-        this._options = options;
-    }
-}
-
 async function fetch(url2) {
     const extDir = path.join(__dirname, '..', 'ext');
     let filePath;
@@ -114,8 +57,6 @@ class DatabaseVM extends VM {
     constructor(globals={}) {
         super(Object.assign({
             chrome,
-            Image,
-            Blob,
             fetch,
             indexedDB: global.indexedDB,
             IDBKeyRange: global.IDBKeyRange,
@@ -127,6 +68,14 @@ class DatabaseVM extends VM {
     }
 }
 
+class DatabaseVMDictionaryImporterMediaLoader {
+    async getImageResolution() {
+        // Placeholder values
+        return {width: 100, height: 100};
+    }
+}
+
 module.exports = {
-    DatabaseVM
+    DatabaseVM,
+    DatabaseVMDictionaryImporterMediaLoader
 };
diff --git a/dev/translator-vm.js b/dev/translator-vm.js
index 3c3886ba..d616afc5 100644
--- a/dev/translator-vm.js
+++ b/dev/translator-vm.js
@@ -18,7 +18,7 @@
 const fs = require('fs');
 const path = require('path');
 const assert = require('assert');
-const {DatabaseVM} = require('./database-vm');
+const {DatabaseVM, DatabaseVMDictionaryImporterMediaLoader} = require('./database-vm');
 const {createDictionaryArchive} = require('./util');
 
 function clone(value) {
@@ -75,7 +75,8 @@ class TranslatorVM extends DatabaseVM {
         const testDictionaryContent = await testDictionary.generateAsync({type: 'arraybuffer'});
 
         // Setup database
-        const dictionaryImporter = new DictionaryImporter();
+        const dictionaryImporterMediaLoader = new DatabaseVMDictionaryImporterMediaLoader();
+        const dictionaryImporter = new DictionaryImporter(dictionaryImporterMediaLoader);
         const dictionaryDatabase = new DictionaryDatabase();
         await dictionaryDatabase.prepare();
 
diff --git a/dev/vm.js b/dev/vm.js
index 363cc115..9db87cdf 100644
--- a/dev/vm.js
+++ b/dev/vm.js
@@ -116,7 +116,7 @@ function deepStrictEqual(actual, expected) {
 }
 
 
-function createURLClass(urlMap) {
+function createURLClass() {
     const BaseURL = URL;
     const result = function URL(url) {
         const u = new BaseURL(url);
@@ -133,23 +133,13 @@ function createURLClass(urlMap) {
         this.searchParams = u.searchParams;
         this.username = u.username;
     };
-    result.createObjectURL = (object) => {
-        const id = crypto.randomBytes(16).toString('hex');
-        const url = `blob:${id}`;
-        urlMap.set(url, object);
-        return url;
-    };
-    result.revokeObjectURL = (url) => {
-        urlMap.delete(url);
-    };
     return result;
 }
 
 
 class VM {
     constructor(context={}) {
-        this._urlMap = new Map();
-        context.URL = createURLClass(this._urlMap);
+        context.URL = createURLClass();
         context.crypto = {
             getRandomValues: (array) => {
                 const buffer = crypto.randomBytes(array.byteLength);
@@ -205,10 +195,6 @@ class VM {
 
         return single ? results[0] : results;
     }
-
-    getUrlObject(url) {
-        return this._urlMap.get(url);
-    }
 }
 
 
diff --git a/ext/js/language/dictionary-importer-media-loader.js b/ext/js/language/dictionary-importer-media-loader.js
new file mode 100644
index 00000000..bbcc5476
--- /dev/null
+++ b/ext/js/language/dictionary-importer-media-loader.js
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2021  Yomichan Authors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/* global
+ * MediaUtil
+ */
+
+/**
+ * Class used for loading and validating media during the dictionary import process.
+ */
+class DictionaryImporterMediaLoader {
+    /**
+     * Attempts to load an image using a base64 encoded content and a media type
+     * and returns its resolution.
+     * @param mediaType The media type for the image content.
+     * @param content The binary content for the image, encoded in base64.
+     * @returns A Promise which resolves with {width, height} on success,
+     *   otherwise an error is thrown.
+     */
+    getImageResolution(mediaType, content) {
+        return new Promise((resolve, reject) => {
+            const image = new Image();
+            const eventListeners = new EventListenerCollection();
+            const cleanup = () => {
+                image.removeAttribute('src');
+                URL.revokeObjectURL(url);
+                eventListeners.removeAllEventListeners();
+            };
+            eventListeners.addEventListener(image, 'load', () => {
+                const {naturalWidth: width, naturalHeight: height} = image;
+                cleanup();
+                resolve({width, height});
+            }, false);
+            eventListeners.addEventListener(image, 'error', () => {
+                cleanup();
+                reject(new Error('Image failed to load'));
+            }, false);
+            const blob = MediaUtil.createBlobFromBase64Content(content, mediaType);
+            const url = URL.createObjectURL(blob);
+            image.src = url;
+        });
+    }
+}
diff --git a/ext/js/language/dictionary-importer.js b/ext/js/language/dictionary-importer.js
index 27b3c44e..b931c929 100644
--- a/ext/js/language/dictionary-importer.js
+++ b/ext/js/language/dictionary-importer.js
@@ -22,11 +22,12 @@
  */
 
 class DictionaryImporter {
-    constructor() {
+    constructor(mediaLoader) {
+        this._mediaLoader = mediaLoader;
         this._schemas = new Map();
     }
 
-    async importDictionary(dictionaryDatabase, archiveSource, details, onProgress) {
+    async importDictionary(dictionaryDatabase, archiveContent, details, onProgress) {
         if (!dictionaryDatabase) {
             throw new Error('Invalid database');
         }
@@ -37,7 +38,7 @@ class DictionaryImporter {
         const hasOnProgress = (typeof onProgress === 'function');
 
         // Read archive
-        const archive = await JSZip.loadAsync(archiveSource);
+        const archive = await JSZip.loadAsync(archiveContent);
 
         // Read and validate index
         const indexFileName = 'index.json';
@@ -469,7 +470,7 @@ class DictionaryImporter {
         let width;
         let height;
         try {
-            ({width, height} = await this._getImageResolution(mediaType, content));
+            ({width, height} = await this._mediaLoader.getImageResolution(mediaType, content));
         } catch (e) {
             throw createError('Could not load image');
         }
@@ -502,36 +503,4 @@ class DictionaryImporter {
         }
         return await response.json();
     }
-
-    /**
-     * Attempts to load an image using a base64 encoded content and a media type
-     * and returns its resolution.
-     * @param mediaType The media type for the image content.
-     * @param content The binary content for the image, encoded in base64.
-     * @returns A Promise which resolves with {width, height} on success,
-     *   otherwise an error is thrown.
-     */
-    _getImageResolution(mediaType, content) {
-        return new Promise((resolve, reject) => {
-            const image = new Image();
-            const eventListeners = new EventListenerCollection();
-            const cleanup = () => {
-                image.removeAttribute('src');
-                URL.revokeObjectURL(url);
-                eventListeners.removeAllEventListeners();
-            };
-            eventListeners.addEventListener(image, 'load', () => {
-                const {naturalWidth: width, naturalHeight: height} = image;
-                cleanup();
-                resolve({width, height});
-            }, false);
-            eventListeners.addEventListener(image, 'error', () => {
-                cleanup();
-                reject(new Error('Image failed to load'));
-            }, false);
-            const blob = MediaUtil.createBlobFromBase64Content(content, mediaType);
-            const url = URL.createObjectURL(blob);
-            image.src = url;
-        });
-    }
 }
diff --git a/ext/js/pages/settings/dictionary-import-controller.js b/ext/js/pages/settings/dictionary-import-controller.js
index db9a1a50..128e18cb 100644
--- a/ext/js/pages/settings/dictionary-import-controller.js
+++ b/ext/js/pages/settings/dictionary-import-controller.js
@@ -19,6 +19,7 @@
  * DictionaryController
  * DictionaryDatabase
  * DictionaryImporter
+ * DictionaryImporterMediaLoader
  */
 
 class DictionaryImportController {
@@ -184,7 +185,8 @@ class DictionaryImportController {
     async _importDictionary(file, importDetails, onProgress) {
         const dictionaryDatabase = await this._getPreparedDictionaryDatabase();
         try {
-            const dictionaryImporter = new DictionaryImporter();
+            const dictionaryImporterMediaLoader = new DictionaryImporterMediaLoader();
+            const dictionaryImporter = new DictionaryImporter(dictionaryImporterMediaLoader);
             const archiveContent = await this._readFile(file);
             const {result, errors} = await dictionaryImporter.importDictionary(dictionaryDatabase, archiveContent, importDetails, onProgress);
             yomichan.api.triggerDatabaseUpdated('dictionary', 'import');
diff --git a/ext/settings.html b/ext/settings.html
index 9d2d9791..cd2376d6 100644
--- a/ext/settings.html
+++ b/ext/settings.html
@@ -3451,6 +3451,7 @@
 <script src="/js/input/hotkey-util.js"></script>
 <script src="/js/language/dictionary-database.js"></script>
 <script src="/js/language/dictionary-importer.js"></script>
+<script src="/js/language/dictionary-importer-media-loader.js"></script>
 <script src="/js/language/sandbox/dictionary-data-util.js"></script>
 <script src="/js/language/sandbox/japanese-util.js"></script>
 <script src="/js/media/audio-system.js"></script>
diff --git a/ext/welcome.html b/ext/welcome.html
index 85022e2c..5c9f4469 100644
--- a/ext/welcome.html
+++ b/ext/welcome.html
@@ -409,6 +409,7 @@
 <script src="/js/input/hotkey-util.js"></script>
 <script src="/js/language/dictionary-database.js"></script>
 <script src="/js/language/dictionary-importer.js"></script>
+<script src="/js/language/dictionary-importer-media-loader.js"></script>
 <script src="/js/media/media-util.js"></script>
 <script src="/js/pages/settings/dictionary-controller.js"></script>
 <script src="/js/pages/settings/dictionary-import-controller.js"></script>
diff --git a/test/test-database.js b/test/test-database.js
index 19ac49e2..ac7e825b 100644
--- a/test/test-database.js
+++ b/test/test-database.js
@@ -18,7 +18,7 @@
 const path = require('path');
 const assert = require('assert');
 const {createDictionaryArchive, testMain} = require('../dev/util');
-const {DatabaseVM} = require('../dev/database-vm');
+const {DatabaseVM, DatabaseVMDictionaryImporterMediaLoader} = require('../dev/database-vm');
 
 
 const vm = new DatabaseVM();
@@ -41,6 +41,12 @@ function createTestDictionaryArchive(dictionary, dictionaryName) {
 }
 
 
+function createDictionaryImporter() {
+    const dictionaryImporterMediaLoader = new DatabaseVMDictionaryImporterMediaLoader();
+    return new DictionaryImporter(dictionaryImporterMediaLoader);
+}
+
+
 function countDictionaryDatabaseEntriesWithTerm(dictionaryDatabaseEntries, term) {
     return dictionaryDatabaseEntries.reduce((i, v) => (i + (v.term === term ? 1 : 0)), 0);
 }
@@ -125,7 +131,7 @@ async function testDatabase1() {
     ];
 
     // Setup database
-    const dictionaryImporter = new DictionaryImporter();
+    const dictionaryImporter = createDictionaryImporter();
     const dictionaryDatabase = new DictionaryDatabase();
     await dictionaryDatabase.prepare();
 
@@ -775,7 +781,7 @@ async function testDatabase2() {
     ]);
 
     // Setup database
-    const dictionaryImporter = new DictionaryImporter();
+    const dictionaryImporter = createDictionaryImporter();
     const dictionaryDatabase = new DictionaryDatabase();
 
     // Error: not prepared
@@ -817,7 +823,7 @@ async function testDatabase3() {
     ];
 
     // Setup database
-    const dictionaryImporter = new DictionaryImporter();
+    const dictionaryImporter = createDictionaryImporter();
     const dictionaryDatabase = new DictionaryDatabase();
     await dictionaryDatabase.prepare();