3 files changed, 14 insertions, 28 deletions

diff --git a/ext/mixed/js/api.js b/ext/mixed/js/api.js
index fa61a1e2..26f4389d 100644
--- a/ext/mixed/js/api.js
+++ b/ext/mixed/js/api.js
@@ -122,30 +122,6 @@ function apiGetDefaultAnkiFieldTemplates() {
 }
 
 function _apiInvoke(action, params={}) {
-    if (!_isBackendReady) {
-        if (_isBackendReadyPromise === null) {
-            _isBackendReadyPromise = new Promise((resolve) => (_isBackendReadyResolve = resolve));
-            const checkBackendReady = async () => {
-                try {
-                    if (await _apiInvokeRaw('isBackendReady')) {
-                        _isBackendReady = true;
-                        _isBackendReadyResolve();
-                    }
-                } catch (e) {
-                    // NOP
-                }
-                setTimeout(checkBackendReady, 100); // poll Backend until it responds
-            };
-            checkBackendReady();
-        }
-        return _isBackendReadyPromise.then(
-            () => _apiInvokeRaw(action, params)
-        );
-    }
-    return _apiInvokeRaw(action, params);
-}
-
-function _apiInvokeRaw(action, params={}) {
     const data = {action, params};
     return new Promise((resolve, reject) => {
         try {
@@ -172,7 +148,3 @@ function _apiInvokeRaw(action, params={}) {
 function _apiCheckLastError() {
     // NOP
 }
-
-let _isBackendReady = false;
-let _isBackendReadyResolve = null;
-let _isBackendReadyPromise = null;
diff --git a/ext/mixed/js/core.js b/ext/mixed/js/core.js
index 83813796..a3cb2459 100644
--- a/ext/mixed/js/core.js
+++ b/ext/mixed/js/core.js
@@ -269,17 +269,26 @@ const yomichan = (() => {
         constructor() {
             super();
 
+            this._isBackendPreparedResolve = null;
+            this._isBackendPreparedPromise = new Promise((resolve) => (this._isBackendPreparedResolve = resolve));
+
             this._messageHandlers = new Map([
+                ['backendPrepared', this._onBackendPrepared.bind(this)],
                 ['getUrl', this._onMessageGetUrl.bind(this)],
                 ['optionsUpdated', this._onMessageOptionsUpdated.bind(this)],
                 ['zoomChanged', this._onMessageZoomChanged.bind(this)]
             ]);
 
             chrome.runtime.onMessage.addListener(this._onMessage.bind(this));
+            chrome.runtime.sendMessage({action: 'yomichanOnline'});
         }
 
         // Public
 
+        prepare() {
+            return this._isBackendPreparedPromise;
+        }
+
         generateId(length) {
             const array = new Uint8Array(length);
             window.crypto.getRandomValues(array);
@@ -305,6 +314,10 @@ const yomichan = (() => {
             return false;
         }
 
+        _onBackendPrepared() {
+            this._isBackendPreparedResolve();
+        }
+
         _onMessageGetUrl() {
             return {url: window.location.href};
         }
diff --git a/ext/mixed/js/display.js b/ext/mixed/js/display.js
index e3e5e7df..6a762a65 100644
--- a/ext/mixed/js/display.js
+++ b/ext/mixed/js/display.js
@@ -153,6 +153,7 @@ class Display {
     }
 
     async prepare(options=null) {
+        await yomichan.prepare();
         const displayGeneratorPromise = this.displayGenerator.prepare();
         const updateOptionsPromise = this.updateOptions(options);
         await Promise.all([displayGeneratorPromise, updateOptionsPromise]);