'use strict';
const fs = require('node:fs');
const path = require('node:path');

function replaceOnce(text, pattern, replacement) {
  const matches = text.match(new RegExp(pattern.source, 'g'));
  if (matches?.length !== 1) throw new Error(`Canonical devcontainer layout changed: ${pattern}`);
  return text.replace(pattern, () => replacement);
}

function profile(
  source,
  {
    native = false,
    ui = false,
    image,
    imageOnly = false,
    ref = 'main',
    playwright,
    url = 'https://github.com/abhigyanpatwari/GitNexus.git',
  } = {},
) {
  if (imageOnly && image) throw new Error('--image cannot be used with image-build');
  if (
    typeof ref !== 'string' ||
    !/^[a-zA-Z0-9][a-zA-Z0-9._/-]*$/.test(ref) ||
    ref === 'HEAD' ||
    ref.includes('..') ||
    ref.endsWith('.') ||
    ref.split('/').some((part) => !part || part.startsWith('.') || part.endsWith('.lock'))
  )
    throw new Error('Invalid clone branch');
  // Character safety check only; Docker validates the image reference grammar.
  if (image && !/^[a-zA-Z0-9][a-zA-Z0-9./:_@-]*$/.test(image))
    throw new Error('Invalid image reference');
  if (
    native &&
    !/^(?:https:\/\/[a-zA-Z0-9.-]+(?::[0-9]+)?\/|ssh:\/\/git@[a-zA-Z0-9.-]+(?::[0-9]+)?\/|git@[a-zA-Z0-9.-]+:)[a-zA-Z0-9._/-]+$/.test(
      url,
    )
  )
    throw new Error('Invalid clone URL; use HTTPS or Git SSH without embedded credentials');
  let result = source;
  if (image) {
    const start = result.indexOf('  "build": {');
    const end = result.indexOf('\n  // Runs on the HOST', start);
    if (start < 0 || end < 0) throw new Error('Canonical build block changed');
    result = result.slice(0, start) + `  "image": ${JSON.stringify(image)},\n` + result.slice(end);
  } else {
    result = replaceOnce(result, /"dockerfile": "Dockerfile"/, '"dockerfile": "../Dockerfile"');
    result = replaceOnce(result, /"context": "\."/, '"context": ".."');
    if (ui) {
      if (!/^[0-9]+\.[0-9]+\.[0-9]+$/.test(playwright))
        throw new Error('Locked Playwright version required');
      result = replaceOnce(
        result,
        /"BUN_VERSION":/,
        `"INSTALL_BROWSER_DEPS": "true",\n      "PLAYWRIGHT_VERSION": ${JSON.stringify(playwright)},\n      "BUN_VERSION":`,
      );
    }
  }
  if (native) {
    result = replaceOnce(
      result,
      /"workspaceMount": "[^"\n]+"/,
      '"workspaceMount": "source=gitnexus-workspace-${devcontainerId},target=/workspace,type=volume"',
    );
    result = replaceOnce(
      result,
      /"CODEX_HOME":/,
      `"GITNEXUS_CLONE_URL": ${JSON.stringify(url)},\n    ` +
        `"GITNEXUS_CLONE_REF": ${JSON.stringify(ref)},\n    "CODEX_HOME":`,
    );
    result = replaceOnce(
      result,
      /"updateContentCommand":/,
      '"onCreateCommand": "node /usr/local/share/gitnexus-devcontainer/bootstrap-native.cjs",\n  "updateContentCommand":',
    );
  }
  if (imageOnly) {
    const start = result.indexOf('  "build": {');
    const end = result.indexOf('\n  // Runs on the HOST', start);
    const features = result.match(/"features": \{[\s\S]*?\n  \},/);
    if (start < 0 || end < 0 || !features)
      throw new Error('Image build requires the canonical build and feature blocks');
    // Publish toolchain metadata only. Lifecycle hooks and host mounts belong
    // to the consuming profile, avoiding duplicate hook execution on attach.
    return '{\n' + result.slice(start, end) + '\n  ' + features[0].slice(0, -1) + '\n}\n';
  }
  if (ui) {
    result = replaceOnce(
      result,
      /"CODEX_HOME":/,
      '"GITNEXUS_DEV_UI": "1",\n    "PLAYWRIGHT_BROWSERS_PATH": "/home/node/.cache/ms-playwright",\n    "CODEX_HOME":',
    );
    result = replaceOnce(
      result,
      /"source=npm-cache-/,
      '"source=playwright-cache-${devcontainerId},target=/home/node/.cache/ms-playwright,type=volume",\n    "source=npm-cache-',
    );
    result = replaceOnce(
      result,
      /"workspaceMount":/,
      '"runArgs": ["--shm-size=1g"],\n  "workspaceMount":',
    );
  }
  return result;
}

module.exports = { profile };
if (require.main === module) {
  const [mode, ...args] = process.argv.slice(2);
  if (!['native', 'ui', 'prebuilt', 'image-build'].includes(mode))
    throw new Error(
      'Usage: node .devcontainer/profile.cjs native [--ui] [--image IMAGE] [--ref BRANCH] [--url URL]\n' +
        '       node .devcontainer/profile.cjs ui [--image IMAGE]\n' +
        '       node .devcontainer/profile.cjs prebuilt [--ui] [--image IMAGE]\n' +
        '       node .devcontainer/profile.cjs image-build [--ui]',
    );
  const options = new Map();
  for (let i = 0; i < args.length; i++) {
    const flag = args[i];
    if (!['--ui', '--image', '--ref', '--url'].includes(flag))
      throw new Error(`Unknown profile argument: ${flag}`);
    if (options.has(flag)) throw new Error(`Duplicate profile argument: ${flag}`);
    if (flag === '--ui') options.set(flag, true);
    else {
      const value = args[++i];
      if (!value || value.startsWith('--')) throw new Error(`${flag} requires a value`);
      options.set(flag, value);
    }
  }
  if (mode === 'image-build' && options.has('--image'))
    throw new Error('--image cannot be used with image-build');
  if (mode !== 'native' && (options.has('--ref') || options.has('--url')))
    throw new Error('--ref and --url require the native profile');
  const lock = JSON.parse(
    fs.readFileSync(path.join(__dirname, '../gitnexus-web/package-lock.json')),
  );
  const output = path.join(__dirname, 'generated');
  const contents = profile(fs.readFileSync(path.join(__dirname, 'devcontainer.json'), 'utf8'), {
    native: mode === 'native',
    ui: mode === 'ui' || options.has('--ui'),
    image:
      options.get('--image') ||
      (mode === 'prebuilt'
        ? `ghcr.io/abhigyanpatwari/gitnexus-devcontainer:main${options.has('--ui') ? '-ui' : ''}`
        : undefined),
    imageOnly: mode === 'image-build',
    ref: options.get('--ref'),
    url: options.get('--url'),
    playwright: lock.packages['node_modules/@playwright/test'].version,
  });
  fs.mkdirSync(output, { recursive: true });
  fs.writeFileSync(path.join(output, 'devcontainer.json'), contents);
  fs.copyFileSync(
    path.join(__dirname, 'devcontainer-lock.json'),
    path.join(output, 'devcontainer-lock.json'),
  );
  console.log(
    'Generated .devcontainer/generated/devcontainer.json; select it when reopening in container. Regenerate after updating the main configuration.',
  );
}