exports.deployment = async (req, res) => {
    try {
    const fs = require('fs');
    const path = require('path');
    const { spawn } = require('child_process');
    const logger = require("../services/logger");
    const providedKey = (req.query.apikey || '').toString();
    const BITBUCKET_API_KEY = process.env.BITBUCKET_API_KEY || '';
    const EXPECTED_REPO = process.env.EXPECTED_REPO;
    const EXPECTED_BRANCH = process.env.EXPECTED_BRANCH;
    const DEPLOY_SCRIPT = process.env.DEPLOY_SCRIPT;

    // Utility: pick branch name from a changes object
    function getBranchNamesFromChanges(changes = []) {
      const names = [];
      for (const ch of changes) {
        if (!ch || typeof ch !== 'object') continue;
        if (ch.new && ch.new.name) names.push(ch.new.name);
        if (ch.old && ch.old.name) names.push(ch.old.name);
        // some payloads may have 'ref' or other places; add if needed
      }
      return names;
    }

    if (!BITBUCKET_API_KEY) {
      // appendLog('ERROR: Server API_KEY not configured in env.');
      logger.info("Server misconfigured - API_KEY");
      return res.status(500).json({ ok: false, message: 'Server misconfigured - API_KEY' });
    }

    if (!EXPECTED_REPO) {
      // appendLog('ERROR: Server API_KEY not configured in env.');
      logger.info("Server misconfigured - REPO");
      return res.status(500).json({ ok: false, message: 'Server misconfigured - REPO ' });
    } 

     if (!EXPECTED_BRANCH) {
      // appendLog('ERROR: Server API_KEY not configured in env.');
      logger.info("Server misconfigured - BRANCH");
      return res.status(500).json({ ok: false, message: 'Server misconfigured - BRANCH ' });
    } 

    if (!DEPLOY_SCRIPT) {
      // appendLog('ERROR: Server API_KEY not configured in env.');
      logger.info("Server misconfigured - Script");
      return res.status(500).json({ ok: false, message: 'Server misconfigured - Script ' });
    } 


    if (!providedKey) {
      // appendLog('ERROR: Server API_KEY not configured in env.');
      logger.info("API key missing");
      return res.status(401).json({ ok: false, message: 'API key missing' });
    } 

     if (providedKey != BITBUCKET_API_KEY) {
      // appendLog('ERROR: Server API_KEY not configured in env.');
      logger.info("Invalid API key");
      return res.status(401).json({ ok: false, message: 'Invalid API key' });
    }
      
    // ##############################################################

      const payload = req.body;
    if (!payload || typeof payload !== 'object') {
      logger.info('BAD_PAYLOAD: empty or invalid JSON body');
      return res.status(400).json({ ok: false, message: 'Invalid payload' });
    }

    const repoFullName = payload.repository && payload.repository.full_name;
    if (repoFullName !== EXPECTED_REPO) {
      logger.info('IGNORED: repo mismatch', 'expected=' + EXPECTED_REPO, 'got=' + repoFullName);
      // do nothing except log
      return res.status(200).json({ ok: true, action: 'ignored', reason: 'repository mismatch' });
    }

    const changes = (payload.push && payload.push.changes) || [];
    const branchNames = getBranchNamesFromChanges(changes);

    const hasMaster = branchNames.includes(EXPECTED_BRANCH);

    if (!hasMaster) {
      logger.info('IGNORED: branch not master', 'branches=' + JSON.stringify(branchNames));
      return res.status(200).json({ ok: true, action: 'ignored', reason: 'branch not as exp' });
    }

    // All checks passed — call the deploy script
    if (!fs.existsSync(DEPLOY_SCRIPT)) {
      logger.info('ERROR: deploy script not found at', DEPLOY_SCRIPT);
      return res.status(500).json({ ok: false, message: 'Deploy script missing' });
    }

    logger.info('DEPLOY_TRIGGER: repo ' + repoFullName +  'branch - ' +  EXPECTED_BRANCH +  'script - ' +  DEPLOY_SCRIPT);

    // spawn the script (non-blocking). Adjust args as required.
    const child = spawn(DEPLOY_SCRIPT, [], {
      cwd: path.dirname(DEPLOY_SCRIPT),
      env: process.env,
       detached: true,
      stdio: ['ignore', 'ignore', 'ignore'] // detach fully
    });
    child.unref();
    // capture output for logs
    // child.stdout.on('data', (d) => logger.info('SCRIPT_OUT:' + d.toString().trim()));
    // child.stderr.on('data', (d) => logger.info('SCRIPT_ERR:' + d.toString().trim()));

    // child.on('close', (code) => logger.info('SCRIPT_EXIT:' + `code=${code}`));
    // child.on('error', (err) => logger.info('SCRIPT_ERROR:' + (err && err.message ? err.message : String(err))) );

    // Respond immediately saying it was started with child id
    return res.status(200).json({ ok: true, action: 'deploy_started', pid: child.pid });

 


    // ##############################################################


    } catch (err) {
      logger.error(err.message);
      logger.error(`Stack trace: ${err.stack}`);
      res.status(500).send({'status':"failed",'message': "Internal server error" });
    }
  };