import { defineConfig } from 'astro/config';
import { readFile, writeFile, stat } from 'node:fs/promises';
import path from 'node:path';
import mdx from '@astrojs/mdx';
import sitemap from '@astrojs/sitemap';

const EXCLUDED_PATHS = new Set([
  'https://unique.rzen.dev/grid/',
  'https://unique.rzen.dev/index3/',
  'https://unique.rzen.dev/404/',
]);

const FIND_ROOT = path.resolve('src/content/find');
const REVIEW_ROOT = path.resolve('src/content/reviews');
const PICK_FILE = path.resolve('src/data/pick.json');
const VALID_SLUG = /^[a-z0-9][a-z0-9-]*$/;
const VALID_TAG = /^[a-z0-9][a-z0-9-]{0,40}$/i;

function readBody(req) {
  return new Promise((resolve, reject) => {
    let data = '';
    req.setEncoding('utf8');
    req.on('data', (c) => { data += c; if (data.length > 8192) reject(new Error('body too large')); });
    req.on('end', () => resolve(data));
    req.on('error', reject);
  });
}

function send(res, status, payload) {
  res.statusCode = status;
  res.setHeader('content-type', 'application/json');
  res.end(JSON.stringify(payload));
}

function parseEditorialTags(fm) {
  const inline = fm.match(/^editorialTags:\s*\[([^\]]*)\]\s*$/m);
  if (inline) {
    return inline[1]
      .split(',')
      .map((s) => s.trim().replace(/^["']|["']$/g, ''))
      .filter(Boolean);
  }
  const list = fm.match(/^editorialTags:\s*\n((?:[ \t]+-[^\n]*\n?)+)/m);
  if (list) {
    return list[1]
      .split('\n')
      .map((line) => line.replace(/^[ \t]+-[ \t]*/, '').trim().replace(/^["']|["']$/g, ''))
      .filter(Boolean);
  }
  if (/^editorialTags:\s*\[\s*\]\s*$/m.test(fm) || /^editorialTags:\s*$/m.test(fm)) return [];
  return null; // field absent
}

function stripEditorialTags(fm) {
  return fm.replace(/^editorialTags:[^\n]*(?:\n[ \t]+-[^\n]*)*\n?/m, '');
}

function formatEditorialTags(tags) {
  return `editorialTags: [${tags.map((t) => JSON.stringify(t)).join(', ')}]`;
}

const editFindTagApi = {
  name: 'edit-find-tag-dev-api',
  apply: 'serve',
  configureServer(server) {
    server.middlewares.use('/api/edit-find-tag', async (req, res, next) => {
      if (req.method !== 'POST') return next();
      try {
        const raw = await readBody(req);
        const { slug, tag, mode } = JSON.parse(raw || '{}');
        if (typeof slug !== 'string' || !VALID_SLUG.test(slug)) return send(res, 400, { error: 'invalid slug' });
        if (typeof tag !== 'string' || !VALID_TAG.test(tag)) return send(res, 400, { error: 'invalid tag' });

        const filePath = path.join(FIND_ROOT, slug, 'index.mdx');
        if (!filePath.startsWith(FIND_ROOT + path.sep)) return send(res, 400, { error: 'path escape' });
        try { await stat(filePath); } catch { return send(res, 404, { error: 'find not found' }); }

        const text = await readFile(filePath, 'utf8');
        const m = text.match(/^---\n([\s\S]*?)\n---\n?([\s\S]*)$/);
        if (!m) return send(res, 422, { error: 'no frontmatter' });
        const fm = m[1];
        const body = m[2];

        const current = parseEditorialTags(fm) ?? [];
        const has = current.includes(tag);
        let next;
        if (mode === 'add') next = has ? current : [...current, tag];
        else if (mode === 'remove') next = current.filter((t) => t !== tag);
        else next = has ? current.filter((t) => t !== tag) : [...current, tag]; // toggle

        const stripped = stripEditorialTags(fm).replace(/\n+$/, '');
        const newFm = next.length
          ? `${stripped}\n${formatEditorialTags(next)}`
          : stripped;
        const out = `---\n${newFm}\n---\n${body}`;
        await writeFile(filePath, out, 'utf8');

        return send(res, 200, { slug, tag, editorialTags: next });
      } catch (err) {
        return send(res, 500, { error: String(err && err.message ? err.message : err) });
      }
    });
  },
};

const setPickApi = {
  name: 'set-pick-dev-api',
  apply: 'serve',
  configureServer(server) {
    server.middlewares.use('/api/set-pick', async (req, res, next) => {
      if (req.method !== 'POST') return next();
      try {
        const raw = await readBody(req);
        const { slug } = JSON.parse(raw || '{}');
        if (typeof slug !== 'string' || !VALID_SLUG.test(slug)) return send(res, 400, { error: 'invalid slug' });

        const reviewPath = path.join(REVIEW_ROOT, slug, 'index.mdx');
        if (!reviewPath.startsWith(REVIEW_ROOT + path.sep)) return send(res, 400, { error: 'path escape' });
        try { await stat(reviewPath); } catch { return send(res, 404, { error: 'review not found' }); }

        await writeFile(PICK_FILE, JSON.stringify({ hero: slug }, null, 2) + '\n', 'utf8');

        return send(res, 200, { slug });
      } catch (err) {
        return send(res, 500, { error: String(err && err.message ? err.message : err) });
      }
    });
  },
};

export default defineConfig({
  site: 'https://unique.rzen.dev',
  trailingSlash: 'always',
  build: { format: 'directory' },
  vite: { plugins: [editFindTagApi, setPickApi] },
  integrations: [
    mdx(),
    sitemap({
      filter: (page) => !EXCLUDED_PATHS.has(page),
      changefreq: 'weekly',
    }),
  ],
});