1 files changed, 101 insertions, 0 deletions
diff --git a/browser/components/search/DomainToCategoriesMap.worker.mjs b/browser/components/search/DomainToCategoriesMap.worker.mjs
new file mode 100644
index 0000000000..07dc52cfb8
--- /dev/null
+++ b/browser/components/search/DomainToCategoriesMap.worker.mjs
@@ -0,0 +1,101 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+import { PromiseWorker } from "resource://gre/modules/workers/PromiseWorker.mjs";
+
+/**
+ * Boilerplate to connect with the main thread PromiseWorker.
+ */
+const worker = new PromiseWorker.AbstractWorker();
+worker.dispatch = function (method, args = []) {
+  return agent[method](...args);
+};
+worker.postMessage = function (message, ...transfers) {
+  self.postMessage(message, ...transfers);
+};
+worker.close = function () {
+  self.close();
+};
+
+self.addEventListener("message", msg => worker.handleMessage(msg));
+self.addEventListener("unhandledrejection", function (error) {
+  throw error.reason;
+});
+
+/**
+ * Stores and manages the Domain-to-Categories Map.
+ */
+class Agent {
+  /**
+   * @type {Map<string, Array<number>>} Hashes mapped to categories and values.
+   */
+  #map = new Map();
+
+  /**
+   * Converts data from the array directly into a Map.
+   *
+   * @param {Array<ArrayBuffer>} fileContents Files
+   * @returns {boolean} Returns whether the Map contains results.
+   */
+  populateMap(fileContents) {
+    this.#map.clear();
+
+    for (let fileContent of fileContents) {
+      let obj;
+      try {
+        obj = JSON.parse(new TextDecoder().decode(fileContent));
+      } catch (ex) {
+        return false;
+      }
+      for (let objKey in obj) {
+        if (Object.hasOwn(obj, objKey)) {
+          this.#map.set(objKey, obj[objKey]);
+        }
+      }
+    }
+    return this.#map.size > 0;
+  }
+
+  /**
+   * Retrieves scores for the hash from the map.
+   *
+   * @param {string} hash Key to look up in the map.
+   * @returns {Array<number>}
+   */
+  getScores(hash) {
+    if (this.#map.has(hash)) {
+      return this.#map.get(hash);
+    }
+    return [];
+  }
+
+  /**
+   * Empties the internal map.
+   *
+   * @returns {boolean}
+   */
+  emptyMap() {
+    this.#map.clear();
+    return true;
+  }
+
+  /**
+   * Test only function to allow the map to contain information without
+   * having to go through Remote Settings.
+   *
+   * @param {object} obj The data to directly import into the Map.
+   * @returns {boolean} Whether the map contains values.
+   */
+  overrideMapForTests(obj) {
+    this.#map.clear();
+    for (let objKey in obj) {
+      if (Object.hasOwn(obj, objKey)) {
+        this.#map.set(objKey, obj[objKey]);
+      }
+    }
+    return this.#map.size > 0;
+  }
+}
+
+const agent = new Agent();