3 files changed, 40 insertions, 54 deletions

diff --git a/ext/js/app/popup.js b/ext/js/app/popup.js
index 7a8b3f8c..4caf8241 100644
--- a/ext/js/app/popup.js
+++ b/ext/js/app/popup.js
@@ -722,22 +722,25 @@ export class Popup extends EventDispatcher {
     }
 
     /**
-     * @param {string} action
-     * @param {import('core').SerializableObject} params
+     * @template {import('display').WindowApiNames} TName
+     * @param {TName} action
+     * @param {import('display').WindowApiParams<TName>} params
      */
-    _invokeWindow(action, params = {}) {
+    _invokeWindow(action, params) {
         const contentWindow = this._frame.contentWindow;
         if (this._frameClient === null || !this._frameClient.isConnected() || contentWindow === null) { return; }
 
-        const message = this._frameClient.createMessage({action, params});
-        contentWindow.postMessage(message, this._targetOrigin);
+        /** @type {import('display').WindowApiMessage<TName>} */
+        const message = {action, params};
+        const messageWrapper = this._frameClient.createMessage(message);
+        contentWindow.postMessage(messageWrapper, this._targetOrigin);
     }
 
     /**
      * @returns {void}
      */
     _onExtensionUnloaded() {
-        this._invokeWindow('displayExtensionUnloaded');
+        this._invokeWindow('displayExtensionUnloaded', void 0);
     }
 
     /**
diff --git a/ext/js/pages/settings/popup-preview-controller.js b/ext/js/pages/settings/popup-preview-controller.js
index 8361809d..e661b738 100644
--- a/ext/js/pages/settings/popup-preview-controller.js
+++ b/ext/js/pages/settings/popup-preview-controller.js
@@ -71,38 +71,41 @@ export class PopupPreviewController {
     /** */
     _onCustomCssChange() {
         const css = /** @type {HTMLTextAreaElement} */ (this._customCss).value;
-        this._invoke('PopupPreviewFrame.setCustomCss', {css});
+        this._invoke('setCustomCss', {css});
     }
 
     /** */
     _onCustomOuterCssChange() {
         const css = /** @type {HTMLTextAreaElement} */ (this._customOuterCss).value;
-        this._invoke('PopupPreviewFrame.setCustomOuterCss', {css});
+        this._invoke('setCustomOuterCss', {css});
     }
 
     /** */
     _onOptionsContextChange() {
         const optionsContext = this._settingsController.getOptionsContext();
-        this._invoke('PopupPreviewFrame.updateOptionsContext', {optionsContext});
+        this._invoke('updateOptionsContext', {optionsContext});
     }
 
     /**
      * @param {import('settings-controller').EventArgument<'optionsChanged'>} details
      */
     _onOptionsChanged({options}) {
-        this._invoke('PopupPreviewFrame.optionsChanged', {options});
+        this._invoke('setLanguageExampleText', {language: options.general.language});
     }
 
     /**
      * @param {import('dom-data-binder').SettingChangedEvent} settingChangedEvent
      */
     _onLanguageSelectChanged(settingChangedEvent) {
-        this._invoke('PopupPreviewFrame.setLanguageExampleText', {language: settingChangedEvent.detail.value});
+        const {value} = settingChangedEvent.detail;
+        if (typeof value !== 'string') { return; }
+        this._invoke('setLanguageExampleText', {language: value});
     }
 
     /**
-     * @param {string} action
-     * @param {import('core').SerializableObject} params
+     * @template {import('popup-preview-frame').ApiNames} TName
+     * @param {TName} action
+     * @param {import('popup-preview-frame').ApiParams<TName>} params
      */
     _invoke(action, params) {
         if (this._frame === null || this._frame.contentWindow === null) { return; }
diff --git a/ext/js/pages/settings/popup-preview-frame.js b/ext/js/pages/settings/popup-preview-frame.js
index 8d881cc6..ad6e420f 100644
--- a/ext/js/pages/settings/popup-preview-frame.js
+++ b/ext/js/pages/settings/popup-preview-frame.js
@@ -18,6 +18,7 @@
 
 import * as wanakana from '../../../lib/wanakana.js';
 import {Frontend} from '../../app/frontend.js';
+import {createApiMap, invokeApiMapHandler} from '../../core/api-map.js';
 import {querySelectorNotNull} from '../../dom/query-selector.js';
 import {TextSourceRange} from '../../dom/text-source-range.js';
 
@@ -58,15 +59,14 @@ export class PopupPreviewFrame {
         this._wanakanaBound = false;
 
         /* eslint-disable @stylistic/no-multi-spaces */
-        /** @type {Map<string, (params: import('core').SerializableObjectAny) => void>} */
-        this._windowMessageHandlers = new Map(/** @type {[key: string, handler: (params: import('core').SerializableObjectAny) => void][]} */ ([
-            ['PopupPreviewFrame.setText',                this._onSetText.bind(this)],
-            ['PopupPreviewFrame.setCustomCss',           this._setCustomCss.bind(this)],
-            ['PopupPreviewFrame.setCustomOuterCss',      this._setCustomOuterCss.bind(this)],
-            ['PopupPreviewFrame.updateOptionsContext',   this._updateOptionsContext.bind(this)],
-            ['PopupPreviewFrame.optionsChanged',         this._onOptionsChanged.bind(this)],
-            ['PopupPreviewFrame.setLanguageExampleText', this._setLanguageExampleText.bind(this)]
-        ]));
+        /** @type {import('popup-preview-frame').ApiMap} */
+        this._windowMessageHandlers = createApiMap([
+            ['setText',                this._onSetText.bind(this)],
+            ['setCustomCss',           this._setCustomCss.bind(this)],
+            ['setCustomOuterCss',      this._setCustomOuterCss.bind(this)],
+            ['updateOptionsContext',   this._updateOptionsContext.bind(this)],
+            ['setLanguageExampleText', this._setLanguageExampleText.bind(this)]
+        ]);
         /* eslint-enable @stylistic/no-multi-spaces */
     }
 
@@ -89,7 +89,7 @@ export class PopupPreviewFrame {
 
         this._languageSummaries = await this._application.api.getLanguageSummaries();
         const options = await this._application.api.optionsGet({current: true});
-        void this._onOptionsChanged({options, optionsContext: {current: true}});
+        void this._setLanguageExampleText({language: options.general.language});
 
         // Overwrite frontend
         this._frontend = new Frontend({
@@ -156,16 +156,13 @@ export class PopupPreviewFrame {
     }
 
     /**
-     * @param {MessageEvent<{action: string, params: import('core').SerializableObject}>} e
+     * @param {MessageEvent<import('popup-preview-frame.js').ApiMessageAny>} event
      */
-    _onMessage(e) {
-        if (e.origin !== this._targetOrigin) { return; }
-
-        const {action, params} = e.data;
-        const handler = this._windowMessageHandlers.get(action);
-        if (typeof handler !== 'function') { return; }
-
-        handler(params);
+    _onMessage(event) {
+        if (event.origin !== this._targetOrigin) { return; }
+        const {action, params} = event.data;
+        const callback = () => {}; // NOP
+        invokeApiMapHandler(this._windowMessageHandlers, action, params, [], callback);
     }
 
     /**
@@ -209,9 +206,7 @@ export class PopupPreviewFrame {
         this._setText(element.value, false);
     }
 
-    /**
-     * @param {{text: string}} details
-     */
+    /** @type {import('popup-preview-frame').ApiHandler<'setText'>} */
     _onSetText({text}) {
         this._setText(text, true);
     }
@@ -242,9 +237,7 @@ export class PopupPreviewFrame {
         node.classList.toggle('placeholder-info-visible', visible);
     }
 
-    /**
-     * @param {{css: string}} details
-     */
+    /** @type {import('popup-preview-frame').ApiHandler<'setCustomCss'>} */
     _setCustomCss({css}) {
         if (this._frontend === null) { return; }
         const popup = this._frontend.popup;
@@ -252,9 +245,7 @@ export class PopupPreviewFrame {
         void popup.setCustomCss(css);
     }
 
-    /**
-     * @param {{css: string}} details
-     */
+    /** @type {import('popup-preview-frame').ApiHandler<'setCustomOuterCss'>} */
     _setCustomOuterCss({css}) {
         if (this._frontend === null) { return; }
         const popup = this._frontend.popup;
@@ -262,9 +253,7 @@ export class PopupPreviewFrame {
         void popup.setCustomOuterCss(css, false);
     }
 
-    /**
-     * @param {{optionsContext: import('settings').OptionsContext}} details
-     */
+    /** @type {import('popup-preview-frame').ApiHandler<'updateOptionsContext'>} */
     async _updateOptionsContext(details) {
         const {optionsContext} = details;
         this._optionsContext = optionsContext;
@@ -274,16 +263,7 @@ export class PopupPreviewFrame {
         await this._updateSearch();
     }
 
-    /**
-     * @param {import('settings-controller').EventArgument<'optionsChanged'>} details
-     */
-    async _onOptionsChanged({options: {general: {language}}}) {
-        this._setLanguageExampleText({language});
-    }
-
-    /**
-     * @param {{language: string}} details
-     */
+    /** @type {import('popup-preview-frame').ApiHandler<'setLanguageExampleText'>} */
     _setLanguageExampleText({language}) {
         const activeLanguage = /** @type {import('language').LanguageSummary} */ (this._languageSummaries.find(({iso}) => iso === language));