import { parseNitterDateTime } from '../../utils/date.js';

/**
 * 트윗 텍스트에서 첫 문단 추출 (title용)
 */
export function extractTitle(text) {
  if (!text) return '';
  const paragraphs = text.split(/\n\n+/);
  return paragraphs[0]?.trim() || '';
}

/**
 * HTML에서 이미지 URL 추출
 */
export function extractImageUrls(html) {
  const urls = [];
  const regex = /href="\/pic\/(orig\/)?media%2F([^"]+)"/g;
  let match;
  while ((match = regex.exec(html)) !== null) {
    const mediaPath = decodeURIComponent(match[2]);
    const cleanPath = mediaPath.split('%3F')[0].split('?')[0];
    urls.push(`https://pbs.twimg.com/media/${cleanPath}`);
  }
  return [...new Set(urls)];
}

/**
 * 텍스트에서 유튜브 videoId 추출
 */
export function extractYoutubeVideoIds(text) {
  if (!text) return [];
  const ids = new Set();

  // youtu.be/{id}
  const shortRegex = /youtu\.be\/([a-zA-Z0-9_-]{11})/g;
  let m;
  while ((m = shortRegex.exec(text)) !== null) {
    ids.add(m[1]);
  }

  // youtube.com/watch?v={id}
  const watchRegex = /youtube\.com\/watch\?v=([a-zA-Z0-9_-]{11})/g;
  while ((m = watchRegex.exec(text)) !== null) {
    ids.add(m[1]);
  }

  // youtube.com/shorts/{id}
  const shortsRegex = /youtube\.com\/shorts\/([a-zA-Z0-9_-]{11})/g;
  while ((m = shortsRegex.exec(text)) !== null) {
    ids.add(m[1]);
  }

  return [...ids];
}

/**
 * HTML에서 프로필 정보 추출
 */
export function extractProfile(html) {
  const profile = { displayName: null, avatarUrl: null };

  const nameMatch = html.match(/class="profile-card-fullname"[^>]*title="([^"]+)"/);
  if (nameMatch) {
    profile.displayName = nameMatch[1].trim();
  }

  const avatarMatch = html.match(/class="profile-card-avatar"[^>]*>[\s\S]*?<img[^>]*src="([^"]+)"/);
  if (avatarMatch) {
    let url = avatarMatch[1];
    const encodedMatch = url.match(/\/pic\/(.+)/);
    if (encodedMatch) {
      url = decodeURIComponent(encodedMatch[1]);
    }
    profile.avatarUrl = url;
  }

  return profile;
}

/**
 * HTML에서 트윗 목록 파싱
 */
export function parseTweets(html, username) {
  const tweets = [];
  const containers = html.split('class="timeline-item ');

  for (let i = 1; i < containers.length; i++) {
    const container = containers[i];

    // 고정/리트윗 제외
    const isPinned = container.includes('class="pinned"');
    const isRetweet = container.includes('class="retweet-header"');
    if (isPinned || isRetweet) continue;

    // 트윗 ID
    const idMatch = container.match(/href="\/[^\/]+\/status\/(\d+)/);
    if (!idMatch) continue;
    const id = idMatch[1];

    // 시간
    const timeMatch = container.match(/<span class="tweet-date"[^>]*><a[^>]*title="([^"]+)"/);
    const time = timeMatch ? parseNitterDateTime(timeMatch[1]) : null;
    if (!time) continue;

    // 텍스트
    const contentMatch = container.match(/<div class="tweet-content[^"]*"[^>]*>([\s\S]*?)<\/div>/);
    let text = '';
    if (contentMatch) {
      text = contentMatch[1]
        .replace(/<br\s*\/?>/g, '\n')
        .replace(/<a[^>]*>([^<]*)<\/a>/g, '$1')
        .replace(/<[^>]+>/g, '')
        .trim();
    }

    // 이미지
    const imageUrls = extractImageUrls(container);

    tweets.push({
      id,
      time,
      text,
      imageUrls,
      url: `https://x.com/${username}/status/${id}`,
    });
  }

  return tweets;
}

/**
 * Nitter에서 단일 트윗 조회
 */
export async function fetchSingleTweet(nitterUrl, username, postId) {
  const url = `${nitterUrl}/${username}/status/${postId}`;
  const res = await fetch(url);

  if (!res.ok) {
    throw new Error(`트윗을 찾을 수 없습니다 (${res.status})`);
  }

  const html = await res.text();

  // 메인 트윗 파싱 (main-tweet ~ replies 사이)
  const mainTweetMatch = html.match(/<div id="m" class="main-tweet">([\s\S]*?)<div id="r" class="replies">/);
  if (!mainTweetMatch) {
    throw new Error('트윗 내용을 파싱할 수 없습니다');
  }

  const container = mainTweetMatch[1];

  // 시간
  const timeMatch = container.match(/<span class="tweet-date"[^>]*><a[^>]*title="([^"]+)"/);
  const time = timeMatch ? parseNitterDateTime(timeMatch[1]) : null;

  // 텍스트
  const contentMatch = container.match(/<div class="tweet-content[^"]*"[^>]*>([\s\S]*?)<\/div>/);
  let text = '';
  if (contentMatch) {
    text = contentMatch[1]
      .replace(/<br\s*\/?>/g, '\n')
      .replace(/<a[^>]*>([^<]*)<\/a>/g, '$1')
      .replace(/<[^>]+>/g, '')
      .trim();
  }

  // 이미지
  const imageUrls = extractImageUrls(container);

  // 프로필 정보
  const profile = extractProfile(html);

  return {
    id: postId,
    time,
    text,
    imageUrls,
    url: `https://x.com/${username}/status/${postId}`,
    profile,
  };
}

/**
 * Nitter에서 트윗 수집 (첫 페이지만)
 */
export async function fetchTweets(nitterUrl, username) {
  const url = `${nitterUrl}/${username}`;
  const res = await fetch(url);
  const html = await res.text();

  // 프로필 정보
  const profile = extractProfile(html);

  // 트윗 파싱
  const tweets = parseTweets(html, username);

  return { tweets, profile };
}

/**
 * Nitter에서 전체 트윗 수집 (페이지네이션)
 */
export async function fetchAllTweets(nitterUrl, username, log) {
  const allTweets = [];
  let cursor = null;
  let pageNum = 1;
  let emptyCount = 0;

  while (true) {
    const url = cursor
      ? `${nitterUrl}/${username}?cursor=${cursor}`
      : `${nitterUrl}/${username}`;

    log?.info(`[페이지 ${pageNum}] 스크래핑 중...`);

    try {
      const res = await fetch(url);
      const html = await res.text();
      const tweets = parseTweets(html, username);

      if (tweets.length === 0) {
        emptyCount++;
        if (emptyCount >= 3) break;
      } else {
        emptyCount = 0;
        allTweets.push(...tweets);
        log?.info(`  -> ${tweets.length}개 추출 (누적: ${allTweets.length})`);
      }

      // 다음 페이지 cursor
      const cursorMatch = html.match(/class="show-more"[^>]*>\s*<a href="\?cursor=([^"]+)"/);
      if (!cursorMatch) break;

      cursor = cursorMatch[1];
      pageNum++;

      await new Promise(r => setTimeout(r, 1000));
    } catch (err) {
      log?.error(`  -> 오류: ${err.message}`);
      emptyCount++;
      if (emptyCount >= 5) break;
      await new Promise(r => setTimeout(r, 3000));
    }
  }

  return allTweets;
}