/**
 * Universal Offload Worker (Remote)
 * 
 * Handles worktree provisioning and parallel task execution based on 'playbooks'.
 */
import { spawn, spawnSync } from 'child_process';
import path from 'path';
import fs from 'fs';

const prNumber = process.argv[2];
const branchName = process.argv[3];
const policyPath = process.argv[4];
const action = process.argv[5] || 'review';

async function main() {
  if (!prNumber || !branchName || !policyPath) {
    console.error('Usage: tsx worker.ts <PR_NUMBER> <BRANCH_NAME> <POLICY_PATH> [action]');
    return 1;
  }

  const workDir = process.cwd(); // This is remoteWorkDir
  const targetDir = path.join(workDir, branchName);

  // 1. Provision PR Directory
  if (!fs.existsSync(targetDir)) {
    console.log(`🌿 Provisioning PR #${prNumber} into ${branchName}...`);
    const cloneCmd = `git clone --filter=blob:none https://github.com/google-gemini/gemini-cli.git ${targetDir}`;
    spawnSync(cloneCmd, { stdio: 'inherit', shell: true });
    
    process.chdir(targetDir);
    spawnSync('gh', ['pr', 'checkout', prNumber], { stdio: 'inherit' });
  } else {
    process.chdir(targetDir);
  }

  const logDir = path.join(targetDir, `.gemini/logs/offload-${prNumber}`);
  fs.mkdirSync(logDir, { recursive: true });

  const geminiBin = path.join(workDir, 'node_modules/.bin/gemini');

  // 2. Define Playbooks
  let tasks: any[] = [];

  if (action === 'review') {
    tasks = [
      { id: 'build', name: 'Fast Build', cmd: `cd ${targetDir} && npm ci && npm run build` },
      { id: 'ci', name: 'CI Checks', cmd: `gh pr checks ${prNumber}` },
      { id: 'review', name: 'Gemini Analysis', cmd: `${geminiBin} --policy ${policyPath} --cwd ${targetDir} -p "/review-frontend ${prNumber}"` },
      { id: 'verify', name: 'Behavioral Proof', cmd: `${geminiBin} --policy ${policyPath} --cwd ${targetDir} -p "Analyze the code in ${targetDir} and exercise it to prove it works."`, dep: 'build' }
    ];
  } else if (action === 'fix') {
    tasks = [
      { id: 'build', name: 'Fast Build', cmd: `cd ${targetDir} && npm ci && npm run build` },
      { id: 'failures', name: 'Find Failures', cmd: `gh run view --log-failed` },
      { id: 'fix', name: 'Iterative Fix', cmd: `${geminiBin} --policy ${policyPath} --cwd ${targetDir} -p "Address review comments and fix failing tests for PR ${prNumber}. Repeat until CI is green."`, dep: 'build' }
    ];
  } else if (action === 'ready') {
    tasks = [
      { id: 'clean', name: 'Clean Install', cmd: `npm run clean && npm ci` },
      { id: 'preflight', name: 'Full Preflight', cmd: `npm run preflight`, dep: 'clean' },
      { id: 'conflicts', name: 'Conflict Check', cmd: `git fetch origin main && git merge-base --is-ancestor origin/main HEAD || echo "CONFLICT"` }
    ];
  } else if (action === 'open') {
    console.log(`🚀 Dropping into manual session for ${branchName}...`);
    process.exit(0);
  }

  const state: Record<string, any> = {};
  tasks.forEach(t => state[t.id] = { status: 'PENDING' });

  return new Promise((resolve) => {
    function runTask(task: any) {
      if (task.dep && state[task.dep].status !== 'SUCCESS') {
        setTimeout(() => runTask(task), 1000);
        return;
      }

      state[task.id].status = 'RUNNING';
      const proc = spawn(task.cmd, { shell: true, env: { ...process.env, FORCE_COLOR: '1' } });
      const logStream = fs.createWriteStream(path.join(logDir, `${task.id}.log`));
      proc.stdout.pipe(logStream);
      proc.stderr.pipe(logStream);

      proc.on('close', (code) => {
        const exitCode = code ?? 0;
        state[task.id].status = exitCode === 0 ? 'SUCCESS' : 'FAILED';
        fs.writeFileSync(path.join(logDir, `${task.id}.exit`), exitCode.toString());
        render();
      });
    }

    function render() {
      console.clear();
      console.log(`==================================================`);
      console.log(`🚀 Offload | ${action.toUpperCase()} | PR #${prNumber}`);
      console.log(`📂 Worktree: ${targetDir}`);
      console.log(`==================================================\n`);
      
      tasks.forEach(t => {
        const s = state[t.id];
        const icon = s.status === 'SUCCESS' ? '✅' : s.status === 'FAILED' ? '❌' : s.status === 'RUNNING' ? '⏳' : '💤';
        console.log(`  ${icon} ${t.name.padEnd(20)}: ${s.status}`);
      });

      const allDone = tasks.every(t => ['SUCCESS', 'FAILED'].includes(state[t.id].status));
      if (allDone) {
        console.log(`\n✨ Playbook complete. Launching interactive session...`);
        resolve(0);
      }
    }

    tasks.filter(t => !t.dep).forEach(runTask);
    tasks.filter(t => t.dep).forEach(runTask);
    const intervalId = setInterval(render, 1500);
    
    const checkAllDone = setInterval(() => {
        if (tasks.every(t => ['SUCCESS', 'FAILED'].includes(state[t.id].status))) {
            clearInterval(intervalId);
            clearInterval(checkAllDone);
        }
    }, 1000);
  });
}

if (import.meta.url === `file://${process.argv[1]}`) {
  runWorker(process.argv.slice(2)).catch(console.error);
}