import { spawn } from 'child_process';
import { existsSync, copyFileSync } from 'fs';
import { join, dirname } from 'path';
import { fileURLToPath } from 'url';

const __dirname = dirname(fileURLToPath(import.meta.url));

const backendDir = join(__dirname, 'backend');
const frontendDir = join(__dirname, 'frontend');
const backendEnv = join(backendDir, '.env');
const backendEnvExample = join(backendDir, '.env.example');

if (!existsSync(backendEnv) && existsSync(backendEnvExample)) {
  console.log('Creating .env from .env.example...');
  copyFileSync(backendEnvExample, backendEnv);
  console.log('Please edit backend/.env and add your DASHSCOPE_API_KEY and DASHSCOPE_APP_ID');
}

const BACKEND_URL = 'http://localhost:3101';
const HEALTH_ENDPOINT = `${BACKEND_URL}/api/health`;

function waitForBackend(maxRetries = 30, interval = 1000) {
  return new Promise((resolve, reject) => {
    let retries = 0;

    const check = async () => {
      try {
        const response = await fetch(HEALTH_ENDPOINT);
        if (response.ok) {
          console.log('Backend is ready!');
          resolve(true);
          return;
        }
      } catch {
      }

      retries++;
      if (retries >= maxRetries) {
        reject(new Error('Backend failed to start'));
        return;
      }

      setTimeout(check, interval);
    };

    check();
  });
}

function startBackend() {
  console.log('Starting backend...');

  const backend = spawn('pnpm', ['dev'], {
    cwd: backendDir,
    shell: true,
    stdio: 'pipe'
  });

  backend.stdout.on('data', (data) => {
    process.stdout.write(`[backend] ${data}`);
  });

  backend.stderr.on('data', (data) => {
    process.stderr.write(`[backend] ${data}`);
  });

  backend.on('close', (code) => {
    if (code !== 0) {
      console.error(`Backend process exited with code ${code}`);
    }
    process.exit(code);
  });

  return backend;
}

function startFrontend() {
  console.log('Starting frontend...');

  const frontend = spawn('pnpm', ['start'], {
    cwd: frontendDir,
    shell: true,
    stdio: 'pipe'
  });

  frontend.stdout.on('data', (data) => {
    process.stdout.write(`[frontend] ${data}`);
  });

  frontend.stderr.on('data', (data) => {
    process.stderr.write(`[frontend] ${data}`);
  });

  frontend.on('close', (code) => {
    if (code !== 0) {
      console.error(`Frontend process exited with code ${code}`);
    }
    process.exit(code);
  });

  return frontend;
}

async function main() {
  console.log('=== Starting Dev Server ===\n');

  const backend = startBackend();

  try {
    await waitForBackend();
    startFrontend();
  } catch (error) {
    console.error(error.message);
    backend.kill();
    process.exit(1);
  }
}

main();