feat: focus on second opening

cmd/app/electron.go

@@ -8,6 +8,7 @@ import (
 	"io"
 	"io/ioutil"
 	stdlog "log"
+	"net/http"
 	"os"
 	"os/exec"
 	"os/signal"
@@ -20,6 +21,7 @@ import (
 	"github.com/BigJk/snd/printing/preview"
 	"github.com/BigJk/snd/rendering"
 	"github.com/BigJk/snd/server"
+	"github.com/labstack/echo/v4"
 
 	"github.com/asticode/go-astikit"
 	"github.com/asticode/go-astilectron"
@@ -33,11 +35,28 @@ var astilectronVersion = "0.0.1"
 
 var prev preview.Preview
 
+var mainWindow *astilectron.Window
+
 // This will change the starting routine so that an additional Electron window
 // will open with the frontend in it.
 func init() {
 	startFunc = startElectron
-	serverOptions = append(serverOptions, server.WithPrinter(&prev))
+	onAlreadyRunning = func() {
+		fmt.Println("ERROR: Sales & Dungeons is already running!")
+
+		// Send GET request to the server to focus the Electron window
+		if _, err := http.Get("http://127.0.0.1:7123/api/focusElectron"); err != nil {
+			fmt.Println("ERROR: could not focus Electron window:", err)
+		}
+	}
+	serverOptions = append(serverOptions, server.WithPrinter(&prev), server.WithAdditionalRoutes(func(api *echo.Group) {
+		api.GET("/focusElectron", func(c echo.Context) error {
+			if mainWindow != nil {
+				go mainWindow.Show()
+			}
+			return c.NoContent(http.StatusOK)
+		})
+	}))
 }
 
 func startElectron(db database.Database, debug bool) {
@@ -83,14 +102,10 @@ contextBridge.exposeInMainWorld("api", {
 	}
 
 	if isMacAppBundle() {
-		home, err := os.UserHomeDir()
-		if err != nil {
-			panic(err)
-		}
-		opts.BaseDirectoryPath = filepath.Join(home, "/Documents/Sales & Dungeons/electron")
-		opts.DataDirectoryPath = filepath.Join(home, "/Documents/Sales & Dungeons/electron")
+		opts.BaseDirectoryPath = filepath.Join(sndDataDir, "/electron")
+		opts.DataDirectoryPath = filepath.Join(sndDataDir, "/electron")
 
-		err = os.MkdirAll(opts.BaseDirectoryPath, 0777)
+		err := os.MkdirAll(opts.BaseDirectoryPath, 0777)
 		log.Info("Changed electron provision folder because of app bundle", log.WithValue("path", opts.BaseDirectoryPath), log.WithValue("mkdir error", err))
 
 		// copy icon files to the electron folder
@@ -133,6 +148,8 @@ contextBridge.exposeInMainWorld("api", {
 		_ = w.OpenDevTools()
 	}
 
+	mainWindow = w
+
 	// Wait for interrupt signal to trigger shutdown of application.
 	go func() {
 		quit := make(chan os.Signal, 1)

cmd/app/main.go

@@ -25,6 +25,9 @@ import (
 
 var serverOptions []server.Option
 var startFunc = startServer
+var onAlreadyRunning = func() {
+	fmt.Println("ERROR: Sales & Dungeons is already running!")
+}
 
 func syncBaseUrl() string {
 	override := os.Getenv("SND_SYNC_BASE_URL")
@@ -70,6 +73,10 @@ func openDatabase() database.Database {
 
 	db, err := badger.New(userdata)
 	if err != nil {
+		if strings.Contains(err.Error(), "Another process is using this Badger database") {
+			onAlreadyRunning()
+			os.Exit(0)
+		}
 		panic(err)
 	}
 
@@ -92,7 +99,14 @@ func openDatabase() database.Database {
 func startServer(db database.Database, debug bool) {
 	rand.Seed(time.Now().UnixNano())
 
-	s, err := server.New(db, append(serverOptions, server.WithDataDir(sndDataDir), server.WithDebug(debug), server.WithPrinter(&cups.CUPS{}), server.WithPrinter(&remote.Remote{}), server.WithPrinter(&serial.Serial{}), server.WithPrinter(&dump.Dump{}))...)
+	s, err := server.New(db, append(serverOptions,
+		server.WithDataDir(sndDataDir),
+		server.WithDebug(debug),
+		server.WithPrinter(&cups.CUPS{}),
+		server.WithPrinter(&remote.Remote{}),
+		server.WithPrinter(&serial.Serial{}),
+		server.WithPrinter(&dump.Dump{}))...,
+	)
 	if err != nil {
 		panic(err)
 	}

server/server.go

@@ -49,13 +49,14 @@ type Option func(s *Server) error
 // Server represents an instance of the S&D server.
 type Server struct {
 	sync.RWMutex
-	debug    bool
-	db       database.Database
-	dataDir  string
-	e        *echo.Echo
-	m        *melody.Melody
-	cache    *cache.Cache
-	printers printing.PossiblePrinter
+	debug            bool
+	db               database.Database
+	dataDir          string
+	e                *echo.Echo
+	m                *melody.Melody
+	cache            *cache.Cache
+	printers         printing.PossiblePrinter
+	additionalRoutes []func(e *echo.Group)
 }
 
 // New creates a new instance of the S&D server.
@@ -101,6 +102,14 @@ func WithDataDir(dir string) Option {
 	}
 }
 
+// WithAdditionalRoutes adds additional routes to the server.
+func WithAdditionalRoutes(routes ...func(e *echo.Group)) Option {
+	return func(s *Server) error {
+		s.additionalRoutes = routes
+		return nil
+	}
+}
+
 // Close closes the server and all its connections.
 func (s *Server) Close() error {
 	ctx, cancel := context.WithTimeout(context.Background(), time.Second*1)
@@ -140,6 +149,10 @@ func (s *Server) Start(bindAddr string) error {
 	api := s.e.Group("/api")
 	extern := api.Group("/extern")
 
+	for i := range s.additionalRoutes {
+		s.additionalRoutes[i](api)
+	}
+
 	api.GET("/dataDir", func(c echo.Context) error {
 		absDir, err := filepath.Abs(s.dataDir)
 		if err != nil {