import { utilityProcess } from 'electron';
import logManager from '@electron/service/logger';

export interface OpenClawGatewayLaunchContext {
  port: number;
  token: string;
  openclawDir: string;
  entryScript: string;
}

export async function launchGatewayProcess(
  context: OpenClawGatewayLaunchContext,
): Promise<Electron.UtilityProcess> {
  const gatewayArgs = [
    'gateway',
    '--port',
    String(context.port),
    '--token',
    context.token,
    '--allow-unconfigured',
  ];

  const env: NodeJS.ProcessEnv = {
    ...process.env,
    OPENCLAW_GATEWAY_TOKEN: context.token,
    OPENCLAW_SKIP_CHANNELS: '1',
    OPENCLAW_NO_RESPAWN: '1',
  };

  logManager.info('Starting OpenClaw Gateway process', {
    port: context.port,
    entryScript: context.entryScript,
    cwd: context.openclawDir,
    args: gatewayArgs,
  });

  return await new Promise<Electron.UtilityProcess>((resolve, reject) => {
    const child = utilityProcess.fork(context.entryScript, gatewayArgs, {
      cwd: context.openclawDir,
      stdio: 'pipe',
      env,
      serviceName: 'OpenClaw Gateway',
    });

    let settled = false;

    const resolveOnce = () => {
      if (settled) return;
      settled = true;
      resolve(child);
    };

    const rejectOnce = (error: Error) => {
      if (settled) return;
      settled = true;
      reject(error);
    };

    child.once('spawn', () => {
      logManager.info('OpenClaw Gateway process spawned', { pid: child.pid });
      resolveOnce();
    });

    child.once('error', (error) => {
      logManager.error('OpenClaw Gateway process spawn error:', error);
      rejectOnce(error);
    });

    child.once('exit', (code) => {
      if (!settled) {
        rejectOnce(new Error(`OpenClaw Gateway exited before spawn completed (code=${code ?? 'unknown'})`));
      }
    });

    child.stderr?.on('data', (data) => {
      const raw = data.toString();
      for (const line of raw.split(/\r?\n/)) {
        const trimmed = line.trim();
        if (trimmed) {
          logManager.warn(`[OpenClaw] ${trimmed}`);
        }
      }
    });
  });
}