feat: option to auto-launch game for prism launcher users

Author: wendellmeset

app.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"net/http"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"sort"
 	"strconv"
@@ -42,6 +43,7 @@ type App struct {
 	ProjectFilePath    string
 	ProjectModified    bool
 	SyncCancelled      bool
+	AutoLaunchGame     bool
 	testResultChan     chan bool
 	closeConfirmChan   chan string
 	mu                 sync.Mutex
@@ -938,19 +940,33 @@ func (a *App) GetTheme() string {
 
 // --- Debug Control ---
 
-func (a *App) StartDebug(mode string, selectedMods []string) error {
+func findPrismLauncher() (string, error) {
+	if path, err := exec.LookPath("prismlauncher"); err == nil {
+		return path, nil
+	}
+	return "", fmt.Errorf("Prism Launcher not found. Install it or turn off Auto Launch Game.")
+}
+
+func (a *App) StartDebug(mode string, selectedMods []string, autoLaunch bool) error {
 	a.mu.Lock()
 	if a.ActiveScan {
 		a.mu.Unlock()
 		return fmt.Errorf("a debug session is already in progress")
 	}
+	a.AutoLaunchGame = autoLaunch
 	modsDir := a.ProjectData.ModsDir
 	a.mu.Unlock()
 
 	if modsDir == "" {
 		return fmt.Errorf("please select a mod folder first")
 	}
 
+	if autoLaunch {
+		if _, err := findPrismLauncher(); err != nil {
+			return fmt.Errorf("Failed to start debug session, Prism Launcher is not installed. Please install Prism Launcher or turn off Auto Launch Game.")
+		}
+	}
+
 	entries, err := os.ReadDir(modsDir)
 	if err != nil {
 		return fmt.Errorf("mod folder does not exist")

debug.go

@@ -4,8 +4,10 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"sort"
+	"time"
 
 	wailsRuntime "github.com/wailsapp/wails/v2/pkg/runtime"
 )
@@ -318,11 +320,46 @@ func (a *App) testGroup(mods []string) bool {
 }
 
 func (a *App) waitForTestResult(modCount int) bool {
-	wailsRuntime.EventsEmit(a.ctx, "test-group-prompt", map[string]int{"count": modCount})
+	if a.AutoLaunchGame {
+		prismPath, err := findPrismLauncher()
+		if err != nil {
+			a.emitLog(fmt.Sprintf("Failed to launch Prism Launcher: %v", err), LogError)
+			wailsRuntime.EventsEmit(a.ctx, "test-group-prompt", map[string]interface{}{
+				"count":       modCount,
+				"auto_launch": false,
+			})
+			result := <-a.testResultChan
+			return result
+		}
+		instanceName := a.getInstanceName()
+		cmd := exec.Command(prismPath, "-l", instanceName)
+		if err := cmd.Start(); err != nil {
+			a.emitLog(fmt.Sprintf("Failed to launch Prism Launcher: %v", err), LogError)
+			wailsRuntime.EventsEmit(a.ctx, "test-group-prompt", map[string]interface{}{
+				"count":       modCount,
+				"auto_launch": false,
+			})
+			result := <-a.testResultChan
+			return result
+		}
+		defer func() {
+			cmd.Process.Kill()
+			time.Sleep(500 * time.Millisecond)
+		}()
+	}
+
+	wailsRuntime.EventsEmit(a.ctx, "test-group-prompt", map[string]interface{}{
+		"count":       modCount,
+		"auto_launch": a.AutoLaunchGame,
+	})
 	result := <-a.testResultChan
 	return result
 }
 
+func (a *App) getInstanceName() string {
+	return filepath.Base(filepath.Dir(filepath.Dir(a.ProjectData.ModsDir)))
+}
+
 func readDirNames(dir string) []string {
 	entries, err := os.ReadDir(dir)
 	if err != nil {

frontend/dist/index.html

@@ -62,6 +62,10 @@ <h3 class="panel-title">Debug Mode</h3>
                             Mode 2: Specific New Mods
                         </label>
                     </div>
+                    <label class="checkbox-label" style="margin-top: 8px; margin-bottom: 8px; display: flex; align-items: center; font-size: 12px; gap: 6px;">
+                        <input type="checkbox" id="auto-launch-checkbox"/>
+                        Auto Launch Game <span style="color: var(--text-secondary);">(Only Works for Prism Launcher)</span>
+                    </label>
                     <button class="btn btn-primary" id="start-debug-btn">Start Debug</button>
                 </div>
 

frontend/dist/src/main.js

@@ -125,7 +125,7 @@ window.runtime.EventsOn("log", function(data) {
 });
 
 window.runtime.EventsOn("test-group-prompt", function(data) {
-    showTestDialog(data.count);
+    showTestDialog(data.count, data.auto_launch);
 });
 
 window.runtime.EventsOn("debug-complete", function(culprit) {
@@ -178,12 +178,16 @@ window.runtime.EventsOn("close-confirm", function() {
     );
 });
 
-function showTestDialog(count) {
+function showTestDialog(count, autoLaunch) {
     testDialogActive = true;
+    var launchText = autoLaunch
+        ? "The game has been launched, please wait and see if Minecraft loads properly"
+        : "Launch Minecraft now and test if it loads properly";
     showModal("Test Launch",
         '<div class="test-dialog-main">' +
         '<h2>Testing ' + count + ' mods</h2>' +
-        '<p>Launch Minecraft now and test if it loads properly.</p>' +
+        '<p>' + launchText + '</p>' +
+        '<p style="font-weight: bold; color: var(--log-error);">MAKE SURE TO CLOSE THE GAME BEFORE SELECTING AN OPTION.</p>' +
         '<p style="color: var(--text-secondary); font-size: 12px;">Only the selected mods are in your mods folder.</p>' +
         '</div>',
         '<button class="btn btn-danger" onclick="cancelDebug()">Cancel Debug</button>' +
@@ -397,7 +401,8 @@ async function startDebugWithSelection(mods, checkId) {
     }
     closeModal();
     try {
-        await window.go.main.App.StartDebug("specific", selected);
+        const autoLaunch = document.getElementById("auto-launch-checkbox").checked;
+        await window.go.main.App.StartDebug("specific", selected, autoLaunch);
         await updateUI();
     } catch (err) {
         await showError("Error", err);
@@ -715,9 +720,11 @@ document.getElementById("start-debug-btn").addEventListener("click", async funct
     const mode = document.querySelector('input[name="mode"]:checked');
     if (!mode) return;
 
+    const autoLaunch = document.getElementById("auto-launch-checkbox").checked;
+
     try {
         if (mode.value === "all") {
-            await window.go.main.App.StartDebug("all", null);
+            await window.go.main.App.StartDebug("all", null, autoLaunch);
         } else {
             const savedMods = await window.go.main.App.GetSavedNewMods();
             if (!savedMods || savedMods.length === 0) {

frontend/dist/src/style.css

@@ -561,6 +561,13 @@ html, body {
     font-size: 13px;
 }
 
+#auto-launch-checkbox {
+    accent-color: var(--accent);
+    width: 15px;
+    height: 15px;
+    cursor: pointer;
+}
+
 .checkbox-item input[type="checkbox"],
 .checkbox-item input[type="radio"] {
     accent-color: var(--accent);