import { mkdir, readFile, readdir, rm, stat, writeFile } from 'node:fs/promises';
import path from 'node:path';
import { fileURLToPath } from 'node:url';
import { nodecg } from './util/nodecg.js';

const CHARACTER_NAMES_FILE = 'fighting-characters.json';
const LOCAL_MANIFEST_FILE = 'manifest.json';

type RemoteGame = {
  title: string;
  slug: string;
  repoFolder: string;
  logoFile: string;
};

type AssetFileEntry = {
  path: string;
  size: number;
  downloadUrl: string;
};

type HttpManifestEntry = string | {
  path?: unknown;
  size?: unknown;
  url?: unknown;
};

const extensionDir = path.dirname(fileURLToPath(import.meta.url));
const bundleRoot = path.resolve(extensionDir, '..');
const assetsRoot = path.join(bundleRoot, 'game-assets');

const assetsRouter = nodecg.Router();

assetsRouter.get('/*', async (req, res) => {
  const wildcardParam = (req.params as Record<string, unknown>)['0']
    ?? (req.params as Record<string, unknown>)[''];
  const requestedPath = Array.isArray(wildcardParam)
    ? String(wildcardParam[0] ?? '')
    : typeof wildcardParam === 'string'
      ? wildcardParam
      : '';
  const normalizedPath = path.normalize(requestedPath).replace(/^(\.\.(?:[\\/]|$))+/, '');
  const filePath = path.resolve(assetsRoot, normalizedPath);

  if (!filePath.startsWith(assetsRoot)) {
    res.status(400).send('Invalid asset path.');
    return;
  }

  try {
    const fileStats = await stat(filePath);
    if (!fileStats.isFile()) {
      res.status(404).send('Asset not found.');
      return;
    }

    res.type(path.extname(filePath));
    res.send(await readFile(filePath));
  } catch {
    res.status(404).send('Asset not found.');
  }
});

nodecg.mount(`/bundles/${nodecg.bundleName}/game-assets`, assetsRouter);

const requestHeaders = {
  'User-Agent': 'scoreko-dev-nodecg-bundle',
};

const getConfiguredAssetsBaseUrl = () => {
  const configuredValue = nodecg.bundleConfig.assetsBaseUrl;
  if (typeof configuredValue !== 'string') {
    return 'http://localhost';
  }

  const trimmed = configuredValue.trim();
  if (!trimmed) {
    return 'http://localhost';
  }

  return trimmed.replace(/\/+$/, '');
};

const emitProgress = (title: string, progress: number, status: 'downloading' | 'completed' | 'error') => {
  nodecg.sendMessage('scoreko-assets:downloadProgress', {
    title,
    progress: Math.max(0, Math.min(100, progress)),
    status,
  });
};

const fetchJson = async <T>(url: string): Promise<T> => {
  const response = await fetch(url, { headers: requestHeaders });
  if (!response.ok) {
    throw new Error(`Error HTTP (${response.status}) al solicitar ${url}`);
  }

  return response.json() as Promise<T>;
};

const normalizeManifestEntry = (entry: HttpManifestEntry, gameTitle: string) => {
  if (typeof entry === 'string') {
    return {
      path: entry,
      size: 0,
      explicitUrl: null,
    };
  }

  if (typeof entry === 'object' && entry !== null && typeof entry.path === 'string') {
    return {
      path: entry.path,
      size: typeof entry.size === 'number' ? entry.size : 0,
      explicitUrl: typeof entry.url === 'string' ? entry.url : null,
    };
  }

  throw new Error(`El ${LOCAL_MANIFEST_FILE} de ${gameTitle} contiene entradas inválidas.`);
};

const titleFromSlug = (slug: string) => slug
  .split('-')
  .filter(Boolean)
  .map((segment) => segment[0].toUpperCase() + segment.slice(1))
  .join(' ');

const listRemoteGames = async (): Promise<RemoteGame[]> => {
  const baseUrl = getConfiguredAssetsBaseUrl();
  const gamesIndexUrl = `${baseUrl}/games/`;
  const response = await fetch(gamesIndexUrl, { headers: requestHeaders });
  if (!response.ok) {
    throw new Error(`Error HTTP (${response.status}) al solicitar ${gamesIndexUrl}`);
  }

  const html = await response.text();
  const hrefMatches = [...html.matchAll(/href=["']([^"']+)["']/gi)].map((match) => match[1]);
  const slugs = hrefMatches
    .map((href) => {
      const withoutQuery = href.split('?')[0]?.split('#')[0] ?? '';
      if (!withoutQuery.endsWith('/')) {
        return null;
      }
      const decoded = decodeURIComponent(withoutQuery);
      const trimmed = decoded.replace(/^\/+|\/+$/g, '');
      if (!trimmed || trimmed.includes('/') || trimmed === '.' || trimmed === '..') {
        return null;
      }
      return trimmed;
    })
    .filter((slug): slug is string => slug !== null);

  const uniqueSlugs = [...new Set(slugs)].sort((left, right) => left.localeCompare(right));
  return uniqueSlugs.map((slug) => ({
    slug,
    repoFolder: slug,
    title: titleFromSlug(slug),
    logoFile: `${slug}.png`,
  }));
};

const listHttpFiles = async (game: RemoteGame): Promise<AssetFileEntry[]> => {
  const baseUrl = getConfiguredAssetsBaseUrl();
  const manifestUrl = `${baseUrl}/games/${game.repoFolder}/${LOCAL_MANIFEST_FILE}`;
  const entries = await fetchJson<HttpManifestEntry[]>(manifestUrl);

  if (!Array.isArray(entries) || entries.length === 0) {
    throw new Error(`No se encontraron archivos en ${manifestUrl}.`);
  }

  return entries.map((rawEntry) => {
    const normalized = normalizeManifestEntry(rawEntry, game.title);
    const cleanPath = normalized.path.replace(/^\/+/, '');

    return {
      path: `games/${game.repoFolder}/${cleanPath}`,
      size: Math.max(0, normalized.size),
      downloadUrl: normalized.explicitUrl ?? `${baseUrl}/games/${game.repoFolder}/${cleanPath}`,
    };
  });
};

const listInstalledGames = async () => {
  const entries = await readdir(assetsRoot, { withFileTypes: true }).catch(() => []);
  return entries.filter((entry) => entry.isDirectory()).map((entry) => entry.name).sort((left, right) => left.localeCompare(right));
};

const parseCharacterNames = (content: string, gameTitle: string) => {
  const parsed = JSON.parse(content) as unknown;
  const names = Array.isArray(parsed)
    ? parsed
    : typeof parsed === 'object' && parsed !== null && Array.isArray((parsed as { characters?: unknown }).characters)
      ? (parsed as { characters: unknown[] }).characters
      : null;

  if (!names || names.some((name) => typeof name !== 'string')) {
    throw new Error(`El archivo ${CHARACTER_NAMES_FILE} de ${gameTitle} no tiene un formato válido.`);
  }

  return names;
};

const listInstalledCharacterNamesByGame = async () => {
  const installedGames = await listInstalledGames();
  const charactersByGame = await Promise.all(installedGames.map(async (slug) => {
    const sourcePath = path.join(assetsRoot, slug, CHARACTER_NAMES_FILE);

    try {
      const fileContent = await readFile(sourcePath, 'utf8');
      const names = parseCharacterNames(fileContent, slug);
      return [slug, names] as const;
    } catch {
      return [slug, []] as const;
    }
  }));

  return Object.fromEntries(charactersByGame) as Record<string, string[]>;
};

const downloadGameAssets = async (gameSlug: string) => {
  const game: RemoteGame = {
    slug: gameSlug,
    repoFolder: gameSlug,
    title: titleFromSlug(gameSlug),
    logoFile: `${gameSlug}.png`,
  };

  emitProgress(game.slug, 0, 'downloading');

  const files = await listHttpFiles(game);
  if (!files.length) {
    throw new Error(`No se encontraron archivos para ${game.title}.`);
  }

  const hasCharacterNamesFile = files.some((file) => file.path.endsWith(`/${CHARACTER_NAMES_FILE}`));
  if (!hasCharacterNamesFile) {
    throw new Error(`No se encontró ${CHARACTER_NAMES_FILE} para ${game.title}.`);
  }

  const totalBytes = files.reduce((acc, file) => acc + (file.size || 0), 0);
  let downloadedBytes = 0;

  const destinationFolder = path.join(assetsRoot, game.slug);
  await rm(destinationFolder, { recursive: true, force: true });

  for (const file of files) {
    const relativePath = file.path.replace(`games/${game.repoFolder}/`, '');
    const targetPath = path.join(destinationFolder, relativePath);
    await mkdir(path.dirname(targetPath), { recursive: true });

    const response = await fetch(file.downloadUrl, { headers: requestHeaders });
    if (!response.ok) {
      throw new Error(`No se pudo descargar ${file.path} (status ${response.status}).`);
    }

    const arrayBuffer = await response.arrayBuffer();
    await writeFile(targetPath, Buffer.from(arrayBuffer));

    downloadedBytes += file.size || 0;
    const progress = totalBytes > 0 ? Math.round((downloadedBytes / totalBytes) * 100) : 100;
    emitProgress(game.slug, progress, 'downloading');
  }

  emitProgress(game.slug, 100, 'completed');

  return {
    title: game.title,
    slug: game.slug,
  };
};

const removeGameAssets = async (gameSlug: string) => {
  const destinationFolder = path.join(assetsRoot, gameSlug);
  await rm(destinationFolder, { recursive: true, force: true });

  return {
    title: titleFromSlug(gameSlug),
    slug: gameSlug,
  };
};

nodecg.listenFor('scoreko-assets:listRemoteGames', async (_payload: unknown, ack) => {
  if (typeof ack !== 'function') {
    return;
  }

  try {
    ack(null, await listRemoteGames());
  } catch (error) {
    ack((error as Error).message);
  }
});

nodecg.listenFor('scoreko-assets:listInstalled', async (_payload: unknown, ack) => {
  if (typeof ack !== 'function') {
    return;
  }

  try {
    ack(null, await listInstalledGames());
  } catch (error) {
    ack((error as Error).message);
  }
});

nodecg.listenFor('scoreko-assets:listCharactersByGame', async (_payload: unknown, ack) => {
  if (typeof ack !== 'function') {
    return;
  }

  try {
    ack(null, await listInstalledCharacterNamesByGame());
  } catch (error) {
    ack((error as Error).message);
  }
});

nodecg.listenFor('scoreko-assets:getAssetsBaseUrl', async (_payload: unknown, ack) => {
  if (typeof ack !== 'function') {
    return;
  }

  try {
    ack(null, { assetsBaseUrl: getConfiguredAssetsBaseUrl() });
  } catch (error) {
    ack((error as Error).message);
  }
});

nodecg.listenFor('scoreko-assets:downloadGame', async (payload: unknown, ack) => {
  if (typeof ack !== 'function') {
    return;
  }

  try {
    const slug = typeof payload === 'object' && payload !== null ? (payload as { slug?: unknown }).slug : undefined;
    if (typeof slug !== 'string') {
      throw new Error('Slug de juego inválido.');
    }

    const downloaded = await downloadGameAssets(slug);
    ack(null, {
      downloaded,
      installedGames: await listInstalledGames(),
    });
  } catch (error) {
    if (typeof payload === 'object' && payload !== null && typeof (payload as { slug?: unknown }).slug === 'string') {
      emitProgress((payload as { slug: string }).slug, 0, 'error');
    }
    ack((error as Error).message);
  }
});

nodecg.listenFor('scoreko-assets:removeGame', async (payload: unknown, ack) => {
  if (typeof ack !== 'function') {
    return;
  }

  try {
    const slug = typeof payload === 'object' && payload !== null ? (payload as { slug?: unknown }).slug : undefined;
    if (typeof slug !== 'string') {
      throw new Error('Slug de juego inválido.');
    }

    const removed = await removeGameAssets(slug);
    ack(null, {
      removed,
      installedGames: await listInstalledGames(),
    });
  } catch (error) {
    ack((error as Error).message);
  }
});