Cleanup yomichan api (#1394)

* Move invokeMessageHandler to core.js

* Move getMessageResponseResult to backghend.js

* Replace getTemporaryListenerResult

8 files changed, 93 insertions, 95 deletions

diff --git a/.eslintrc.json b/.eslintrc.json
index fca1449b..369d26ab 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -111,6 +111,7 @@
                 "deepEqual": "readonly",
                 "generateId": "readonly",
                 "promiseAnimationFrame": "readonly",
+                "invokeMessageHandler": "readonly",
                 "log": "readonly",
                 "DynamicProperty": "readonly",
                 "EventDispatcher": "readonly",
diff --git a/ext/js/app/frontend.js b/ext/js/app/frontend.js
index 02707f41..92366d6e 100644
--- a/ext/js/app/frontend.js
+++ b/ext/js/app/frontend.js
@@ -238,7 +238,7 @@ class Frontend {
     _onRuntimeMessage({action, params}, sender, callback) {
         const messageHandler = this._runtimeMessageHandlers.get(action);
         if (typeof messageHandler === 'undefined') { return false; }
-        return yomichan.invokeMessageHandler(messageHandler, params, callback, sender);
+        return invokeMessageHandler(messageHandler, params, callback, sender);
     }
 
     _onZoomChanged({newZoomFactor}) {
@@ -455,7 +455,7 @@ class Frontend {
     async _getIframeProxyPopup() {
         const targetFrameId = 0; // Root frameId
         try {
-            await this._waitForFrontendReady(targetFrameId);
+            await this._waitForFrontendReady(targetFrameId, 10000);
         } catch (e) {
             // Root frame not available
             return await this._getDefaultPopup();
@@ -613,21 +613,40 @@ class Frontend {
         }
     }
 
-    async _waitForFrontendReady(frameId) {
-        const promise = yomichan.getTemporaryListenerResult(
-            chrome.runtime.onMessage,
-            ({action, params}, {resolve}) => {
-                if (
-                    action === 'frontendReady' &&
-                    params.frameId === frameId
-                ) {
-                    resolve();
+    async _waitForFrontendReady(frameId, timeout) {
+        return new Promise((resolve, reject) => {
+            let timeoutId = null;
+
+            const cleanup = () => {
+                if (timeoutId !== null) {
+                    clearTimeout(timeoutId);
+                    timeoutId = null;
                 }
-            },
-            10000
-        );
-        yomichan.api.broadcastTab('requestFrontendReadyBroadcast', {frameId: this._frameId});
-        await promise;
+                chrome.runtime.onMessage.removeListener(onMessage);
+            };
+            const onMessage = (message, sender, sendResponse) => {
+                try {
+                    const {action, params} = message;
+                    if (action === 'frontendReady' && params.frameId === frameId) {
+                        cleanup();
+                        resolve();
+                        sendResponse();
+                    }
+                } catch (e) {
+                    // NOP
+                }
+            };
+
+            if (timeout !== null) {
+                timeoutId = setTimeout(() => {
+                    timeoutId = null;
+                    cleanup();
+                    reject(new Error(`Wait for frontend ready timed out after ${timeout}ms`));
+                }, timeout);
+            }
+
+            chrome.runtime.onMessage.addListener(onMessage);
+        });
     }
 
     _getPreventMiddleMouseValueForPageType(preventMiddleMouseOptions) {
diff --git a/ext/js/background/backend.js b/ext/js/background/backend.js
index 698724fc..d88c5853 100644
--- a/ext/js/background/backend.js
+++ b/ext/js/background/backend.js
@@ -307,7 +307,7 @@ class Backend {
             }
         }
 
-        return yomichan.invokeMessageHandler(messageHandler, params, callback, sender);
+        return invokeMessageHandler(messageHandler, params, callback, sender);
     }
 
     _onConnect(port) {
@@ -1563,7 +1563,7 @@ class Backend {
         return new Promise((resolve, reject) => {
             const callback = (response) => {
                 try {
-                    resolve(yomichan.getMessageResponseResult(response));
+                    resolve(this._getMessageResponseResult(response));
                 } catch (error) {
                     reject(error);
                 }
@@ -1573,6 +1573,21 @@ class Backend {
         });
     }
 
+    _getMessageResponseResult(response) {
+        let error = chrome.runtime.lastError;
+        if (error) {
+            throw new Error(error.message);
+        }
+        if (!isObject(response)) {
+            throw new Error('Tab did not respond');
+        }
+        error = response.error;
+        if (error) {
+            throw deserializeError(error);
+        }
+        return response.result;
+    }
+
     async _checkTabUrl(tabId, urlPredicate) {
         let tab;
         try {
diff --git a/ext/js/comm/cross-frame-api.js b/ext/js/comm/cross-frame-api.js
index 7dbfb411..461ad45d 100644
--- a/ext/js/comm/cross-frame-api.js
+++ b/ext/js/comm/cross-frame-api.js
@@ -191,7 +191,7 @@ class CrossFrameAPIPort extends EventDispatcher {
         }
 
         const callback = (data) => this._sendResult(id, data);
-        return yomichan.invokeMessageHandler(messageHandler, params, callback);
+        return invokeMessageHandler(messageHandler, params, callback);
     }
 
     _sendResponse(data) {
diff --git a/ext/js/core.js b/ext/js/core.js
index 4384d9f0..9b95c407 100644
--- a/ext/js/core.js
+++ b/ext/js/core.js
@@ -342,6 +342,42 @@ function promiseAnimationFrame(timeout=null) {
 }
 
 /**
+ * Invokes a standard message handler. This function is used to react and respond
+ * to communication messages within the extension.
+ * @param handler A handler function which is passed `params` and `...extraArgs` as arguments.
+ * @param async Whether or not the handler is async or not. Values include `false`, `true`, or `'dynamic'`.
+ *   When the value is `'dynamic'`, the handler should return an object of the format `{async: boolean, result: any}`.
+ * @param params Information which was passed with the original message.
+ * @param callback A callback function which is invoked after the handler has completed. The value passed
+ *   to the function is in the format:
+ *   * `{result: any}` if the handler invoked successfully.
+ *   * `{error: object}` if the handler thew an error. The error is serialized.
+ * @param extraArgs Additional arguments which are passed to the `handler` function.
+ * @returns `true` if the function is invoked asynchronously, `false` otherwise.
+ */
+function invokeMessageHandler({handler, async}, params, callback, ...extraArgs) {
+    try {
+        let promiseOrResult = handler(params, ...extraArgs);
+        if (async === 'dynamic') {
+            ({async, result: promiseOrResult} = promiseOrResult);
+        }
+        if (async) {
+            promiseOrResult.then(
+                (result) => { callback({result}); },
+                (error) => { callback({error: serializeError(error)}); }
+            );
+            return true;
+        } else {
+            callback({result: promiseOrResult});
+            return false;
+        }
+    } catch (error) {
+        callback({error: serializeError(error)});
+        return false;
+    }
+}
+
+/**
  * Base class controls basic event dispatching.
  */
 class EventDispatcher {
diff --git a/ext/js/display/display.js b/ext/js/display/display.js
index b7477bb8..a7c45f19 100644
--- a/ext/js/display/display.js
+++ b/ext/js/display/display.js
@@ -463,7 +463,7 @@ class Display extends EventDispatcher {
         if (typeof messageHandler === 'undefined') { return; }
 
         const callback = () => {}; // NOP
-        yomichan.invokeMessageHandler(messageHandler, params, callback);
+        invokeMessageHandler(messageHandler, params, callback);
     }
 
     _onMessageSetOptionsContext({optionsContext}) {
diff --git a/ext/js/display/search-display-controller.js b/ext/js/display/search-display-controller.js
index 3b48af44..d1a4593f 100644
--- a/ext/js/display/search-display-controller.js
+++ b/ext/js/display/search-display-controller.js
@@ -104,7 +104,7 @@ class SearchDisplayController {
     _onMessage({action, params}, sender, callback) {
         const messageHandler = this._messageHandlers.get(action);
         if (typeof messageHandler === 'undefined') { return false; }
-        return yomichan.invokeMessageHandler(messageHandler, params, callback, sender);
+        return invokeMessageHandler(messageHandler, params, callback, sender);
     }
 
     _onKeyDown(e) {
diff --git a/ext/js/yomichan.js b/ext/js/yomichan.js
index 107694e9..1eae2d4d 100644
--- a/ext/js/yomichan.js
+++ b/ext/js/yomichan.js
@@ -120,42 +120,6 @@ class Yomichan extends EventDispatcher {
         }
     }
 
-    getTemporaryListenerResult(eventHandler, userCallback, timeout=null) {
-        if (!(
-            typeof eventHandler.addListener === 'function' &&
-            typeof eventHandler.removeListener === 'function'
-        )) {
-            throw new Error('Event handler type not supported');
-        }
-
-        return new Promise((resolve, reject) => {
-            const runtimeMessageCallback = ({action, params}, sender, sendResponse) => {
-                let timeoutId = null;
-                if (timeout !== null) {
-                    timeoutId = setTimeout(() => {
-                        timeoutId = null;
-                        eventHandler.removeListener(runtimeMessageCallback);
-                        reject(new Error(`Listener timed out in ${timeout} ms`));
-                    }, timeout);
-                }
-
-                const cleanupResolve = (value) => {
-                    if (timeoutId !== null) {
-                        clearTimeout(timeoutId);
-                        timeoutId = null;
-                    }
-                    eventHandler.removeListener(runtimeMessageCallback);
-                    sendResponse();
-                    resolve(value);
-                };
-
-                userCallback({action, params}, {resolve: cleanupResolve, sender});
-            };
-
-            eventHandler.addListener(runtimeMessageCallback);
-        });
-    }
-
     sendMessage(...args) {
         try {
             return chrome.runtime.sendMessage(...args);
@@ -174,43 +138,6 @@ class Yomichan extends EventDispatcher {
         }
     }
 
-    getMessageResponseResult(response) {
-        let error = chrome.runtime.lastError;
-        if (error) {
-            throw new Error(error.message);
-        }
-        if (!isObject(response)) {
-            throw new Error('Tab did not respond');
-        }
-        error = response.error;
-        if (error) {
-            throw deserializeError(error);
-        }
-        return response.result;
-    }
-
-    invokeMessageHandler({handler, async}, params, callback, ...extraArgs) {
-        try {
-            let promiseOrResult = handler(params, ...extraArgs);
-            if (async === 'dynamic') {
-                ({async, result: promiseOrResult} = promiseOrResult);
-            }
-            if (async) {
-                promiseOrResult.then(
-                    (result) => { callback({result}); },
-                    (error) => { callback({error: serializeError(error)}); }
-                );
-                return true;
-            } else {
-                callback({result: promiseOrResult});
-                return false;
-            }
-        } catch (error) {
-            callback({error: serializeError(error)});
-            return false;
-        }
-    }
-
     triggerExtensionUnloaded() {
         this._isExtensionUnloaded = true;
         if (this._isTriggeringExtensionUnloaded) { return; }
@@ -235,7 +162,7 @@ class Yomichan extends EventDispatcher {
     _onMessage({action, params}, sender, callback) {
         const messageHandler = this._messageHandlers.get(action);
         if (typeof messageHandler === 'undefined') { return false; }
-        return this.invokeMessageHandler(messageHandler, params, callback, sender);
+        return invokeMessageHandler(messageHandler, params, callback, sender);
     }
 
     _onMessageIsReady() {