From 90e66a7ad4efd471f1a1f8dc8ed504e911218a75 Mon Sep 17 00:00:00 2001
From: Lea Anthony <lea.anthony@gmail.com>
Date: Mon, 3 Jul 2023 19:52:50 +1000
Subject: [PATCH] [v3] Add PanicHandler application option.

---
 v3/pkg/application/application.go         | 63 +++++++++++------------
 v3/pkg/application/application_windows.go |  8 ---
 v3/pkg/application/options_application.go |  3 ++
 3 files changed, 34 insertions(+), 40 deletions(-)

diff --git a/v3/pkg/application/application.go b/v3/pkg/application/application.go
index f584c56a6..b7207044e 100644
--- a/v3/pkg/application/application.go
+++ b/v3/pkg/application/application.go
@@ -157,6 +157,25 @@ type (
 	}
 )
 
+func processPanic(value any) {
+	if value == nil {
+		value = fmt.Errorf("unknown error")
+	}
+	if globalApplication.options.PanicHandler != nil {
+		globalApplication.options.PanicHandler(value)
+		return
+	}
+	// Print the panic details
+	fmt.Printf("Panic occurred: %v", value)
+
+	// Print the stack trace
+	buf := make([]byte, 1<<16)
+	runtime.Stack(buf, true)
+	fmt.Println("Stack trace:")
+	fmt.Println(string(buf))
+	os.Exit(1)
+}
+
 // Messages sent from javascript get routed here
 type windowMessage struct {
 	windowId uint
@@ -365,6 +384,14 @@ func (a *App) NewSystemTray() *SystemTray {
 
 func (a *App) Run() error {
 	a.info("Starting application")
+
+	// Setup panic handler
+	defer func() {
+		if err := recover(); err != nil {
+			processPanic(err)
+		}
+	}()
+
 	a.impl = newPlatformApp(a)
 	go func() {
 		for {
@@ -683,14 +710,7 @@ func invokeSync(fn func()) {
 	globalApplication.dispatchOnMainThread(func() {
 		defer func() {
 			if err := recover(); err != nil {
-				// Print the panic details
-				fmt.Println("Panic occurred:", err)
-
-				// Print the stack trace
-				buf := make([]byte, 1<<16)
-				runtime.Stack(buf, true)
-				fmt.Println("Stack trace:")
-				fmt.Println(string(buf))
+				processPanic(err)
 			}
 		}()
 		fn()
@@ -705,14 +725,7 @@ func invokeSyncWithResult[T any](fn func() T) (res T) {
 	globalApplication.dispatchOnMainThread(func() {
 		defer func() {
 			if err := recover(); err != nil {
-				// Print the panic details
-				fmt.Println("Panic occurred:", err)
-
-				// Print the stack trace
-				buf := make([]byte, 1<<16)
-				runtime.Stack(buf, true)
-				fmt.Println("Stack trace:")
-				fmt.Println(string(buf))
+				processPanic(err)
 			}
 		}()
 		res = fn()
@@ -728,14 +741,7 @@ func invokeSyncWithError(fn func() error) (err error) {
 	globalApplication.dispatchOnMainThread(func() {
 		defer func() {
 			if err := recover(); err != nil {
-				// Print the panic details
-				fmt.Println("Panic occurred:", err)
-
-				// Print the stack trace
-				buf := make([]byte, 1<<16)
-				runtime.Stack(buf, true)
-				fmt.Println("Stack trace:")
-				fmt.Println(string(buf))
+				processPanic(err)
 			}
 		}()
 		err = fn()
@@ -751,14 +757,7 @@ func invokeSyncWithResultAndError[T any](fn func() (T, error)) (res T, err error
 	globalApplication.dispatchOnMainThread(func() {
 		defer func() {
 			if err := recover(); err != nil {
-				// Print the panic details
-				fmt.Println("Panic occurred:", err)
-
-				// Print the stack trace
-				buf := make([]byte, 1<<16)
-				runtime.Stack(buf, true)
-				fmt.Println("Stack trace:")
-				fmt.Println(string(buf))
+				processPanic(err)
 			}
 		}()
 		res, err = fn()
diff --git a/v3/pkg/application/application_windows.go b/v3/pkg/application/application_windows.go
index db478ef6c..e7a9c0d2e 100644
--- a/v3/pkg/application/application_windows.go
+++ b/v3/pkg/application/application_windows.go
@@ -172,20 +172,12 @@ func (m *windowsApp) setApplicationMenu(menu *Menu) {
 }
 
 func (m *windowsApp) run() error {
-	// Add a hook to the ApplicationDidFinishLaunching event
-	//m.parent.On(events.Mac.ApplicationDidFinishLaunching, func() {
-	//	C.setApplicationShouldTerminateAfterLastWindowClosed(C.bool(m.parent.options.Mac.ApplicationShouldTerminateAfterLastWindowClosed))
-	//	C.setActivationPolicy(C.int(m.parent.options.Mac.ActivationPolicy))
-	//	C.activateIgnoringOtherApps()
-	//})
-	// setup event listeners
 	for eventID := range m.parent.applicationEventListeners {
 		m.on(eventID)
 	}
 
 	_ = m.runMainLoop()
 
-	//C.run()
 	return nil
 }
 
diff --git a/v3/pkg/application/options_application.go b/v3/pkg/application/options_application.go
index 001dd0529..7892822d0 100644
--- a/v3/pkg/application/options_application.go
+++ b/v3/pkg/application/options_application.go
@@ -21,6 +21,9 @@ type Options struct {
 	Assets  AssetOptions
 	Plugins map[string]Plugin
 	Flags   map[string]any
+
+	// PanicHandler is a way to register a custom panic handler
+	PanicHandler func(any)
 }
 
 // AssetOptions defines the configuration of the AssetServer.