Organize WKScriptMessageHandler message handling (home-assistant#3566)

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Documentation: home-assistant/companion.home-assistant#

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Author: bgoncal

Sources/App/WebView/WebViewController+WKScriptMessageHandler.swift

@@ -27,72 +27,94 @@ extension WebViewController: WKScriptMessageHandler {
 
         switch WKUserContentControllerMessage(rawValue: message.name) {
         case .externalBus:
-            webViewExternalMessageHandler.handleExternalMessage(messageBody)
+            handleExternalBus(messageBody)
         case .updateThemeColors:
-            handleThemeUpdate(messageBody)
+            handleUpdateThemeColors(messageBody)
         case .getExternalAuth:
-            guard let callbackName = messageBody["callback"] else { return }
-
-            let force = messageBody["force"] as? Bool ?? false
-
-            Current.Log.verbose("getExternalAuth called, forced: \(force)")
-
-            firstly {
-                Current.api(for: server)?.tokenManager
-                    .authDictionaryForWebView(forceRefresh: force) ??
-                    .init(error: HomeAssistantAPI.APIError.noAPIAvailable)
-            }.done { dictionary in
-                let jsonData = try? JSONSerialization.data(withJSONObject: dictionary)
-                if let jsonString = String(data: jsonData!, encoding: .utf8) {
-                    let script = "\(callbackName)(true, \(jsonString))"
-                    self.webView.evaluateJavaScript(script, completionHandler: { result, error in
-                        if let error {
-                            Current.Log.error("Failed to trigger getExternalAuth callback: \(error)")
-                        }
-
-                        Current.Log.verbose("Success on getExternalAuth callback: \(String(describing: result))")
-                    })
-                }
-            }.catch { error in
-                self.webView.evaluateJavaScript("\(callbackName)(false, 'Token unavailable')")
-                Current.Log.error("Failed to authenticate webview: \(error)")
-            }
+            handleGetExternalAuth(messageBody)
         case .revokeExternalAuth:
-            guard let callbackName = messageBody["callback"] else { return }
-
-            Current.Log.warning("Revoking access token")
-
-            firstly {
-                Current.api(for: server)?.tokenManager
-                    .revokeToken() ?? .init(error: HomeAssistantAPI.APIError.noAPIAvailable)
-            }.done { [server] _ in
-                Current.servers.remove(identifier: server.identifier)
+            handleRevokeExternalAuth(messageBody)
+        case .logError:
+            handleLogError(messageBody)
+        default:
+            Current.Log.error("unknown message: \(message.name)")
+        }
+    }
 
-                let script = "\(callbackName)(true)"
+    /// Handle theme changes from frontend, updating local cache and UI
+    private func handleThemeUpdate(_ messageBody: [String: Any]) {
+        ThemeColors.updateCache(with: messageBody, for: traitCollection)
+        styleUI()
+    }
 
-                Current.Log.verbose("Running revoke external auth callback \(script)")
+    /// Handles externalBus messages by passing them to the webViewExternalMessageHandler.
+    private func handleExternalBus(_ messageBody: [String: Any]) {
+        webViewExternalMessageHandler.handleExternalMessage(messageBody)
+    }
 
-                self.webView.evaluateJavaScript(script, completionHandler: { _, error in
-                    Current.onboardingObservation.needed(.logout)
+    /// Updates the theme colors based on the message body.
+    private func handleUpdateThemeColors(_ messageBody: [String: Any]) {
+        handleThemeUpdate(messageBody)
+    }
 
+    /// Retrieves an authentication token for the web view and invokes a JavaScript callback with the result.
+    private func handleGetExternalAuth(_ messageBody: [String: Any]) {
+        guard let callbackName = messageBody["callback"] else { return }
+        let force = messageBody["force"] as? Bool ?? false
+
+        Current.Log.verbose("getExternalAuth called, forced: \(force)")
+
+        firstly {
+            Current.api(for: server)?.tokenManager
+                .authDictionaryForWebView(forceRefresh: force) ??
+                .init(error: HomeAssistantAPI.APIError.noAPIAvailable)
+        }.done { dictionary in
+            let jsonData = try? JSONSerialization.data(withJSONObject: dictionary)
+            if let jsonString = String(data: jsonData!, encoding: .utf8) {
+                let script = "\(callbackName)(true, \(jsonString))"
+                self.webView.evaluateJavaScript(script, completionHandler: { result, error in
                     if let error {
-                        Current.Log.error("Failed calling sign out callback: \(error)")
+                        Current.Log.error("Failed to trigger getExternalAuth callback: \(error)")
                     }
-
-                    Current.Log.verbose("Successfully informed web client of log out.")
+                    Current.Log.verbose("Success on getExternalAuth callback: \(String(describing: result))")
                 })
-            }.catch { error in
-                Current.Log.error("Failed to revoke token: \(error)")
             }
-        case .logError:
-            Current.Log.error("WebView error: \(messageBody.description.replacingOccurrences(of: "\n", with: " "))")
-        default:
-            Current.Log.error("unknown message: \(message.name)")
+        }.catch { error in
+            self.webView.evaluateJavaScript("\(callbackName)(false, 'Token unavailable')")
+            Current.Log.error("Failed to authenticate webview: \(error)")
         }
     }
 
-    func handleThemeUpdate(_ messageBody: [String: Any]) {
-        ThemeColors.updateCache(with: messageBody, for: traitCollection)
-        styleUI()
+    /// Revokes the current authentication token and informs the web view via a JavaScript callback.
+    private func handleRevokeExternalAuth(_ messageBody: [String: Any]) {
+        guard let callbackName = messageBody["callback"] else { return }
+
+        Current.Log.warning("Revoking access token")
+
+        firstly {
+            Current.api(for: server)?.tokenManager
+                .revokeToken() ?? .init(error: HomeAssistantAPI.APIError.noAPIAvailable)
+        }.done { [server] _ in
+            Current.servers.remove(identifier: server.identifier)
+            let script = "\(callbackName)(true)"
+
+            Current.Log.verbose("Running revoke external auth callback \(script)")
+
+            self.webView.evaluateJavaScript(script, completionHandler: { _, error in
+                Current.onboardingObservation.needed(.logout)
+
+                if let error {
+                    Current.Log.error("Failed calling sign out callback: \(error)")
+                }
+
+                Current.Log.verbose("Successfully informed web client of log out.")
+            })
+        }.catch { error in
+            Current.Log.error("Failed to revoke token: \(error)")
+        }
+    }
+
+    private func handleLogError(_ messageBody: [String: Any]) {
+        Current.Log.error("WebView error: \(messageBody.description.replacingOccurrences(of: "\n", with: " "))")
     }
 }