refactor(display): use chrome devtools protocol (#38)

display/pkg/start_screen.go

@@ -0,0 +1,117 @@
+package pkg
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"image/color"
+	"log/slog"
+	"net"
+	"os"
+	"plg-mudics/shared"
+	"strings"
+
+	"plg-mudics/display/browser"
+
+	"github.com/skip2/go-qrcode"
+)
+
+func OpenStartScreen() {
+	var err error
+
+	raw := shared.RawSplashScreenTemplate
+	html := strings.ReplaceAll(raw, "%%APP-VERSION%%", shared.Version)
+
+	ip, err := getDeviceIp()
+	if err != nil {
+		slog.Error("Failed to get device IP", "error", err)
+	}
+	mac, err := getDeviceMac()
+	if err != nil {
+		slog.Error("Failed to get device MAC address", "error", err)
+	}
+
+	port := 8080
+	showQrCode := !isPortFree(port)
+	qrCodePath := ""
+	if showQrCode {
+		qrCodePath, err = generateQRCode(fmt.Sprintf("http://%s:%d", ip, port))
+		if err != nil {
+			slog.Error("could not generate qr code", "error", err)
+		}
+	}
+
+	var templateBuffer bytes.Buffer
+	startScreenTemplate(html, ip, mac, qrCodePath).Render(context.Background(), &templateBuffer)
+	browser.Browser.OpenHTML(templateBuffer.String())
+}
+
+func getDeviceIp() (string, error) {
+	addrs, err := net.InterfaceAddrs()
+	if err != nil {
+		return "", fmt.Errorf("failed to get network interfaces: %w", err)
+	}
+	for _, addr := range addrs {
+		ipNet, ok := addr.(*net.IPNet)
+		if ok && !ipNet.IP.IsLoopback() && ipNet.IP.To4() != nil {
+			return ipNet.IP.String(), nil
+		}
+	}
+
+	return "", fmt.Errorf("no suitable IP address found")
+}
+
+func isPortFree(port int) bool {
+	addr := fmt.Sprintf("127.0.0.1:%d", port)
+	l, err := net.Listen("tcp", addr)
+	if err != nil {
+		return false
+	}
+	_ = l.Close()
+	return true
+}
+
+func getDeviceMac() (string, error) {
+	interfaces, err := net.Interfaces()
+	if err != nil {
+		return "", fmt.Errorf("failed to get network interfaces: %w", err)
+	}
+
+	for _, interf := range interfaces {
+		mac := interf.HardwareAddr.String()
+		if mac != "" {
+			return mac, nil
+		}
+	}
+
+	return "", fmt.Errorf("no suitable MAC address found")
+}
+
+func generateQRCode(data string) (string, error) {
+	qr, err := qrcode.New(data, qrcode.Medium)
+	if err != nil {
+		return "", fmt.Errorf("could not generate qr code: %w", err)
+	}
+
+	qr.DisableBorder = true
+	qr.ForegroundColor = color.RGBA{R: 0x1c, G: 0x19, B: 0x17, A: 0xff}
+	qr.BackgroundColor = color.RGBA{R: 0xe7, G: 0xe5, B: 0xe4, A: 0xff}
+
+	png, err := qr.PNG(-1)
+	if err != nil {
+		return "", fmt.Errorf("could not render qr code: %w", err)
+	}
+
+	file, err := os.CreateTemp("", "mudics-qr-code-*.png")
+	if err != nil {
+		return "", fmt.Errorf("could not save qr code: %w", err)
+	}
+	defer file.Close()
+
+	_, err = file.Write(png)
+	if err != nil {
+		return "", fmt.Errorf("could not write qr code to file: %w", err)
+	}
+
+	return file.Name(), nil
+}