1 files changed, 64 insertions, 0 deletions
diff --git a/ext/js/dictionary/dictionary-worker-media-loader.js b/ext/js/dictionary/dictionary-worker-media-loader.js
new file mode 100644
index 00000000..e19a13d3
--- /dev/null
+++ b/ext/js/dictionary/dictionary-worker-media-loader.js
@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2023  Yomitan Authors
+ * Copyright (C) 2021-2022  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/>.
+ */
+
+import {generateId} from '../core.js';
+import {ExtensionError} from '../core/extension-error.js';
+
+/**
+ * Class used for loading and validating media from a worker thread
+ * during the dictionary import process.
+ */
+export class DictionaryWorkerMediaLoader {
+    /**
+     * Creates a new instance of the media loader.
+     */
+    constructor() {
+        /** @type {Map<string, {resolve: (result: import('dictionary-worker-media-loader').ImageDetails) => void, reject: (reason?: import('core').RejectionReason) => void}>} */
+        this._requests = new Map();
+    }
+
+    /**
+     * Handles a response message posted to the worker thread.
+     * @param {import('dictionary-worker-media-loader').HandleMessageParams} params Details of the response.
+     */
+    handleMessage(params) {
+        const {id} = params;
+        const request = this._requests.get(id);
+        if (typeof request === 'undefined') { return; }
+        this._requests.delete(id);
+        const {error} = params;
+        if (typeof error !== 'undefined') {
+            request.reject(ExtensionError.deserialize(error));
+        } else {
+            request.resolve(params.result);
+        }
+    }
+
+    /** @type {import('dictionary-importer-media-loader').GetImageDetailsFunction} */
+    getImageDetails(content, mediaType) {
+        return new Promise((resolve, reject) => {
+            const id = generateId(16);
+            this._requests.set(id, {resolve, reject});
+            // This is executed in a Worker context, so the self needs to be force cast
+            /** @type {Worker} */ (/** @type {unknown} */ (self)).postMessage({
+                action: 'getImageDetails',
+                params: {id, content, mediaType}
+            }, [content]);
+        });
+    }
+}