akai-utils/electron/main.js

const { app, BrowserWindow, dialog } = require('electron');
const path = require('path');
const { spawn } = require('child_process');

let mainWindow;
let serverProcess;
let serverPort = 0;

function findServerBinary() {
  const candidates = [
    path.join(__dirname, '..', 'akai-fetch'),
    path.join(__dirname, '..', 'fetch'),
    path.join(process.resourcesPath, 'akai-fetch'),
    path.join(process.resourcesPath, 'fetch'),
  ];
  for (const p of candidates) {
    try {
      require('fs').accessSync(p, require('fs').constants.X_OK);
      return p;
    } catch (_) {}
  }
  return null;
}

async function startServer() {
  const bin = findServerBinary();
  if (!bin) {
    dialog.showErrorBox('Missing Binary',
      'Could not find fetch/akai-fetch binary. Place it next to the app or in resources.');
    app.quit();
    return;
  }

  const usePort = process.env.AKAI_PORT ? parseInt(process.env.AKAI_PORT) : 0;

  return new Promise((resolve, reject) => {
    serverProcess = spawn(bin, ['serve', '-p', String(usePort), '--no-browser'], {
      stdio: ['pipe', 'pipe', 'pipe'],
    });

    let output = '';
    serverProcess.stdout.on('data', (data) => {
      output += data.toString();
      const m = output.match(/Local:\s+http:\/\/localhost:(\d+)/);
      if (m) {
        serverPort = parseInt(m[1]);
        resolve();
      }
    });

    serverProcess.stderr.on('data', (data) => {
      console.error('[server]', data.toString().trim());
    });

    serverProcess.on('error', (err) => {
      console.error('Failed to start server:', err);
      reject(err);
    });

    serverProcess.on('close', (code) => {
      if (serverPort === 0) {
        reject(new Error(`Server exited with code ${code}`));
      }
    });
  });
}

async function createWindow() {
  try {
    await startServer();
  } catch (err) {
    dialog.showErrorBox('Server Error', String(err));
    app.quit();
    return;
  }

  mainWindow = new BrowserWindow({
    width: 1200,
    height: 800,
    minWidth: 800,
    minHeight: 600,
    title: 'AKAI Utils',
    backgroundColor: '#1a1a2e',
    webPreferences: {
      preload: path.join(__dirname, 'preload.js'),
      contextIsolation: true,
      nodeIntegration: false,
    },
  });

  mainWindow.loadURL(`http://localhost:${serverPort}`);
  mainWindow.setMenuBarVisibility(false);

  mainWindow.on('closed', () => {
    mainWindow = null;
  });
}

app.whenReady().then(createWindow);

app.on('window-all-closed', () => {
  if (serverProcess) {
    serverProcess.kill();
    serverProcess = null;
  }
  if (process.platform !== 'darwin') {
    app.quit();
  }
});

app.on('activate', () => {
  if (mainWindow === null) {
    createWindow();
  }
});

app.on('before-quit', () => {
  if (serverProcess) {
    serverProcess.kill();
    serverProcess = null;
  }
});