import { execFileSync } from 'node:child_process';
import { existsSync, readFileSync } from 'node:fs';
import path from 'node:path';

const DEFAULT_BASE = 'https://acs.apps.bokdev.in';
const projectRoot = process.cwd();

function argValue(name, fallback) {
  const prefix = `--${name}=`;
  const inline = process.argv.find((arg) => arg.startsWith(prefix));
  if (inline) return inline.slice(prefix.length);
  const index = process.argv.indexOf(`--${name}`);
  if (index >= 0 && process.argv[index + 1]) return process.argv[index + 1];
  return fallback;
}

function ok(message) {
  console.log(`[ok] ${message}`);
}

function fail(message) {
  console.error(`[fail] ${message}`);
  process.exitCode = 1;
}

function warn(message) {
  console.warn(`[warn] ${message}`);
}

function readLocal(relativePath) {
  return readFileSync(path.join(projectRoot, relativePath), 'utf8');
}

function git(args) {
  return execFileSync('git', args, {
    cwd: projectRoot,
    encoding: 'utf8',
    stdio: ['ignore', 'pipe', 'pipe'],
  }).trim();
}

async function checkJson(base, route) {
  const url = new URL(route, base).toString();
  try {
    const response = await fetch(url);
    const body = await response.text();
    if (!response.ok) {
      fail(`${route} returned HTTP ${response.status}: ${body.slice(0, 160)}`);
      return;
    }
    const parsed = JSON.parse(body);
    if (parsed?.ok !== true) {
      fail(`${route} response did not include ok=true: ${body.slice(0, 160)}`);
      return;
    }
    ok(`${route} ${response.status}`);
  } catch (error) {
    fail(`${route} check failed: ${error instanceof Error ? error.message : String(error)}`);
  }
}

function cookieHeaderFrom(response) {
  if (typeof response.headers.getSetCookie === 'function') {
    return response.headers.getSetCookie().map((cookie) => cookie.split(';')[0]).join('; ');
  }
  const cookie = response.headers.get('set-cookie');
  return cookie ? cookie.split(',').map((part) => part.split(';')[0]).join('; ') : '';
}

async function login(base, username, password) {
  if (!username || !password) return '';

  const url = new URL('/api/auth/login', base).toString();
  try {
    const response = await fetch(url, {
      method: 'POST',
      headers: { 'content-type': 'application/json' },
      body: JSON.stringify({ username, password }),
    });
    const body = await response.text();
    if (!response.ok) {
      fail(`/api/auth/login returned HTTP ${response.status}: ${body.slice(0, 160)}`);
      return '';
    }
    ok('/api/auth/login 200');
    return cookieHeaderFrom(response);
  } catch (error) {
    fail(`/api/auth/login check failed: ${error instanceof Error ? error.message : String(error)}`);
    return '';
  }
}

async function checkTemplate(base, cookie) {
  const route = '/api/visit-requests/template';
  const url = new URL(route, base).toString();
  try {
    const response = await fetch(url, cookie ? { headers: { cookie } } : undefined);
    const contentType = response.headers.get('content-type') ?? '';
    const disposition = response.headers.get('content-disposition') ?? '';

    if (!response.ok) {
      const body = await response.text();
      fail(`${route} returned HTTP ${response.status}: ${body.slice(0, 200)}`);
      return;
    }
    if (!contentType.includes('spreadsheet') && !disposition.includes('.xlsx')) {
      fail(`${route} did not look like an xlsx download: content-type=${contentType || '-'}, content-disposition=${disposition || '-'}`);
      return;
    }
    ok(`${route} xlsx download`);
  } catch (error) {
    fail(`${route} check failed: ${error instanceof Error ? error.message : String(error)}`);
  }
}

function checkLocalTemplate() {
  const templatePath = 'docs/form_sample.xlsx';
  if (!existsSync(path.join(projectRoot, templatePath))) {
    fail(`${templatePath} is missing locally`);
    return;
  }
  ok(`${templatePath} exists locally`);

  try {
    git(['ls-files', '--error-unmatch', templatePath]);
    ok(`${templatePath} is tracked by git`);
  } catch {
    fail(`${templatePath} is not tracked by git`);
  }
}

function checkDockerPackaging() {
  const dockerignore = readLocal('.dockerignore');
  const dockerfile = readLocal('Dockerfile');

  if (!dockerignore.includes('!docs/form_sample.xlsx')) {
    fail('.dockerignore does not allow docs/form_sample.xlsx into the build context');
  } else {
    ok('.dockerignore allows docs/form_sample.xlsx');
  }

  if (!dockerfile.includes('COPY docs/form_sample.xlsx ./docs/form_sample.xlsx')) {
    fail('Dockerfile does not copy docs/form_sample.xlsx into the runtime image');
  } else {
    ok('Dockerfile copies docs/form_sample.xlsx into the runtime image');
  }
}

function checkGitState() {
  try {
    const head = git(['rev-parse', '--short', 'HEAD']);
    ok(`local HEAD ${head}`);

    const upstream = git(['rev-parse', '--abbrev-ref', '--symbolic-full-name', '@{u}']);
    const aheadBehind = git(['rev-list', '--left-right', '--count', `${upstream}...HEAD`]).split(/\s+/);
    const behind = Number(aheadBehind[0] ?? 0);
    const ahead = Number(aheadBehind[1] ?? 0);
    if (ahead || behind) {
      warn(`branch differs from ${upstream}: ahead ${ahead}, behind ${behind}`);
    } else {
      ok(`branch matches ${upstream}`);
    }
  } catch (error) {
    warn(`git state check skipped: ${error instanceof Error ? error.message : String(error)}`);
  }
}

const base = argValue('base', DEFAULT_BASE).replace(/\/+$/, '/');
const username = argValue('username', process.env.ACS_CHECK_USER ?? '');
const password = argValue('password', process.env.ACS_CHECK_PASSWORD ?? '');
console.log(`[acs-deploy-check] base=${base}`);

checkLocalTemplate();
checkDockerPackaging();
checkGitState();
await checkJson(base, '/healthz');
await checkJson(base, '/db');
const cookie = await login(base, username, password);
await checkTemplate(base, cookie);

if (process.exitCode) {
  console.error('[acs-deploy-check] failed');
  process.exit(process.exitCode);
}

console.log('[acs-deploy-check] passed');