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

const __dirname = dirname(fileURLToPath(import.meta.url));
const LOCAL_BIN = join(__dirname, '..', 'sitespeed.io', 'bin', 'sitespeed.js');

// Shell-escape a single argument (single-quote wrapping)
function q(arg) {
  return `'${String(arg).replace(/'/g, "'\\''")}'`;
}

export function runTest(job, onLine) {
  return new Promise((resolve, reject) => {
    const outputFolder = join(__dirname, 'reports', job.id);
    const isDocker = !!process.env.IN_DOCKER;

    const sitespeedArgs = [
      job.url,
      '--browser', job.browser,
      '-n', String(job.runs),
      '--outputFolder', outputFolder,
      '--json',
      '--sustainable.enable',
      '--axe.enable',
      '--coach',
    ];

    if (job.mobile) sitespeedArgs.push('--mobile');

    if (isDocker) {
      sitespeedArgs.push('--browsertime.chrome.args', 'no-sandbox');
      sitespeedArgs.push('--browsertime.chrome.args', 'disable-dev-shm-usage');
      sitespeedArgs.push('--browsertime.chrome.args', 'disable-gpu');
    }

    const env = { ...process.env, DISPLAY: process.env.DISPLAY || ':99' };

    let child;

    if (isDocker) {
      // In Docker, sitespeed.io is on PATH but execSync can't see it from Node's
      // limited environment. Use 'sh -c' so the full shell PATH is used.
      const shellCmd = ['sitespeed.io', ...sitespeedArgs].map(q).join(' ');
      onLine(`[runner] sh -c ${shellCmd.slice(0, 120)}...`);
      onLine(`[runner] DISPLAY=${env.DISPLAY}`);
      child = spawn('sh', ['-c', shellCmd], { cwd: __dirname, env });
    } else {
      if (!existsSync(LOCAL_BIN)) {
        return reject(new Error(
          `Local sitespeed.io not found at ${LOCAL_BIN}\n` +
          `Run: cd /home/malin/c0ding/sitespeed.io && npm install`
        ));
      }
      onLine(`[runner] node ${LOCAL_BIN.slice(-40)}...`);
      child = spawn('node', [LOCAL_BIN, ...sitespeedArgs], { cwd: __dirname, env });
    }

    const allLines = [];

    child.stdout.on('data', (data) => {
      const lines = data.toString().split('\n').filter(Boolean);
      for (const line of lines) { allLines.push(line); onLine(line); }
    });

    child.stderr.on('data', (data) => {
      const lines = data.toString().split('\n').filter(Boolean);
      for (const line of lines) { allLines.push('[stderr] ' + line); onLine('[stderr] ' + line); }
    });

    child.on('close', (code) => {
      if (code === 0) {
        resolve(outputFolder);
      } else {
        const tail = allLines.slice(-20).join('\n');
        reject(new Error(`sitespeed.io exited with code ${code}\n${tail}`));
      }
    });

    child.on('error', (err) => {
      reject(new Error(`Failed to spawn process: ${err.message}`));
    });
  });
}