'use strict';

const API = 'https://api.mangadex.org';
const { parse } = require('../plugins/registry');
const { localizedTitle, chapterNumber, selectChapterReleases, availabilitySummary, pageUrls } = require('../plugins/mangadex');
const { sourceDate } = require('../../chapter-dates');

function mangaDexInfo(value) {
  let url;
  try { url = new URL(String(value)); } catch { return null; }
  if (url.protocol !== 'https:' || !['mangadex.org', 'www.mangadex.org'].includes(url.hostname)) return null;
  const match = /^\/title\/([0-9a-f]{8}-[0-9a-f]{4}-[1-5][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12})(?:\/([^/?#]+))?\/?$/i.exec(url.pathname);
  if (!match) return null;
  const id = match[1].toLowerCase();
  const title = decodeURIComponent(match[2] || id).replace(/[-_]+/g, ' ').trim();
  return { source: 'mangadex', id, title, url: `https://mangadex.org/title/${id}${match[2] ? `/${match[2]}` : ''}` };
}

async function jsonGet(http, url) {
  const response = await http.get(url, { accept: 'application/json' });
  const body = await response.json();
  if (body.result && body.result !== 'ok') throw new Error(`MangaDex API result: ${body.result}`);
  return body;
}

async function discoverMangaDexCatalog(seriesUrl, http) {
  const info = mangaDexInfo(seriesUrl);
  if (!info) throw new Error('Invalid MangaDex title URL');
  const manga = (await jsonGet(http, `${API}/manga/${info.id}`)).data;
  if (!manga || manga.type !== 'manga') throw new Error('MangaDex title was not found');
  const metadata = parse('mangadex', 'metadata', { data: manga, url: `${API}/manga/${info.id}` });

  const releases = [];
  let offset = 0;
  for (;;) {
    const params = new URLSearchParams({ limit: '100', offset: String(offset), includeFutureUpdates: '0', includeExternalUrl: '0' });
    params.append('translatedLanguage[]', 'en');
    params.append('includes[]', 'scanlation_group');
    params.append('order[chapter]', 'asc');
    const page = await jsonGet(http, `${API}/manga/${info.id}/feed?${params}`);
    releases.push(...parse('mangadex', 'feed', { data: page.data || [], url: `${API}/manga/${info.id}/feed` }).releases);
    offset += page.data?.length || 0;
    if (!page.data?.length || offset >= Number(page.total || 0)) break;
  }

  const { title, specialLabel } = metadata;
  const parseCatalog = externalReleases => parse('mangadex', 'catalog', {
    data: { attributes: metadata.availabilityAttributes, releases, specialLabel, externalReleases },
    url: `${API}/manga/${info.id}`,
  });
  let parsed = parseCatalog(null);
  const chapters = parsed.chapters;
  // External-only is a separate feed mode, not a combined hosted+external catalog.
  let externalReleases = null;
  if (!chapters.length) {
    const params = new URLSearchParams({ limit: '1', includeFutureUpdates: '0', includeExternalUrl: '1' });
    params.append('translatedLanguage[]', 'en');
    externalReleases = Number((await jsonGet(http, `${API}/manga/${info.id}/feed?${params}`)).total || 0);
    parsed = parseCatalog(externalReleases);
  }
  return {
    id: info.id,
    title,
    originalLanguage: metadata.originalLanguage,
    links: metadata.links,
    availability: parsed.availability,
    chapters,
  };
}

async function discoverMangaDexChapter(ref, http) {
  const atHome = await jsonGet(http, `${API}/at-home/server/${ref.id}?forcePort443=true`);
  const groupName = ref.group?.name ? ` · ${ref.group.name}` : '';
  const parsed = parse('mangadex', 'atHome', { data: { response: atHome, chapterUrl: ref.url, expectedPages: ref.pages }, url: `${API}/at-home/server/${ref.id}` });
  const source = sourceDate(ref.uploadedAt, `MangaDex${groupName}`, ref.uploadBatch);
  return {
    number: ref.number, title: ref.title || '', ...(source ? { dates: { source } } : {}),
    ...(ref.special ? { special: true, label: ref.label, sourceId: ref.id, sourceNumber: ref.sourceNumber ?? null } : {}),
    source: { name: `MangaDex${groupName}`, url: ref.url },
    pages: parsed.pages,
  };
}

module.exports = {
  API, mangaDexInfo, localizedTitle, chapterNumber, selectChapterReleases, availabilitySummary,
  discoverMangaDexCatalog, discoverMangaDexChapter, pageUrls,
};