import { existsSync, readFileSync, readdirSync, statSync } from 'node:fs';
import path from 'node:path';

const root = process.cwd();
const checks = [];

function record(level, label, detail = '') {
  checks.push({ level, label, detail });
}

function pass(label, detail = '') {
  record('PASS', label, detail);
}

function warn(label, detail = '') {
  record('WARN', label, detail);
}

function fail(label, detail = '') {
  record('FAIL', label, detail);
}

function file(rel) {
  return path.join(root, rel);
}

function read(rel) {
  return readFileSync(file(rel), 'utf8');
}

function requireFile(rel, label = rel) {
  if (existsSync(file(rel))) pass(label);
  else fail(label, `${rel} is missing`);
}

function requireText(rel, patterns, label = rel) {
  if (!existsSync(file(rel))) {
    fail(label, `${rel} is missing`);
    return;
  }
  const text = read(rel);
  for (const pattern of patterns) {
    if (typeof pattern === 'string' ? text.includes(pattern) : pattern.test(text)) {
      pass(`${label}: ${pattern.toString()}`);
    } else {
      fail(`${label}: ${pattern.toString()}`, 'not found');
    }
  }
}

function walk(rel, predicate, hits = []) {
  const abs = file(rel);
  if (!existsSync(abs)) return hits;
  for (const name of readdirSync(abs)) {
    if (['node_modules', 'dist', '.npm-cache'].includes(name)) continue;
    const childRel = path.join(rel, name);
    const childAbs = file(childRel);
    const stat = statSync(childAbs);
    if (stat.isDirectory()) walk(childRel, predicate, hits);
    else if (predicate(childRel)) hits.push(childRel);
  }
  return hits;
}

requireFile('package.json');
requireFile('backend/package.json');
requireFile('backend/prisma/schema.prisma');
requireFile('.env.prod.example');
requireFile('backend/.env.example');
requireFile('nginx/nginx.conf.example');
requireFile('DEPLOY.md');
requireFile('SECURITY.md');

requireText('package.json', [
  '"check:no-cdn"',
  '"check:responsive"',
  '"check:seo"',
  '"preflight:prod"',
  'generate-article-pages',
  'compress-dist',
], 'frontend scripts');

requireText('backend/package.json', [
  '"build": "tsc"',
  '"test": "node --test tests/*.test.mjs"',
  '"prisma:generate"',
  '"prisma:apply"',
  '"seed"',
], 'backend scripts');

requireText('.env.prod.example', [
  'DATABASE_URL=',
  'REDIS_URL=',
  'SESSION_SECRET=',
  'COOKIE_DOMAIN=".teknav.ir"',
  'CORS_ORIGINS="https://www.teknav.ir,https://teknav.ir"',
  'UPLOAD_DIR="/var/lib/teknav/uploads"',
  'VAPID_PUBLIC_KEY=',
  'VAPID_PRIVATE_KEY=',
  'ZARINPAL_MERCHANT_ID=',
  'STORAGE_BACKEND="local"',
], 'production env template');

requireText('backend/.env.example', [
  'SMTP_HOST=',
  'SMS_PROVIDER=',
  'VAPID_PUBLIC_KEY=',
  'ZARINPAL_MERCHANT_ID=',
  'STORAGE_BACKEND=local',
], 'backend env example');

requireText('nginx/nginx.conf.example', [
  'location = /ACCOUNTS.md',
  /location ~ \^\/api\/\(admin\/stream\|auth\/notifications\/stream\)\$/,
  /proxy_buffering\s+off;/,
  'gzip_static on',
], 'nginx production template');

const accountLeaks = ['public/ACCOUNTS.md', 'dist/ACCOUNTS.md'].filter((rel) => existsSync(file(rel)));
if (accountLeaks.length) fail('operator credentials not public', accountLeaks.join(', '));
else pass('operator credentials not public');

const migrationsDir = file('backend/prisma/migrations');
if (existsSync(migrationsDir)) pass('Prisma migrations directory present');
else warn('Prisma migrations directory absent', 'production currently relies on prisma:apply/db push fallback');

const engineArtifacts = walk('backend', (rel) =>
  /(^|\/)(query_engine.*\.node(\.gz)?|schema-engine.*(\.gz)?)$/.test(rel),
);
if (engineArtifacts.length) fail('no generated Prisma engine artifacts committed', engineArtifacts.join(', '));
else pass('no generated Prisma engine artifacts committed');

const backendTests = walk('backend/tests', (rel) => rel.endsWith('.test.mjs'));
if (backendTests.length >= 2) pass('backend test coverage files', `${backendTests.length} test files`);
else warn('backend test coverage files', `${backendTests.length} test file(s); add more domain tests`);

const output = checks.map(({ level, label, detail }) => `${level} ${label}${detail ? ` - ${detail}` : ''}`);
console.log(output.join('\n'));

const failures = checks.filter((item) => item.level === 'FAIL');
const warnings = checks.filter((item) => item.level === 'WARN');
console.log(`\nProduction readiness: ${failures.length} failure(s), ${warnings.length} warning(s).`);

if (failures.length) process.exit(1);