// 获取弹幕 API 路由
import { NextRequest, NextResponse } from 'next/server';

import { getConfig } from '@/lib/config';

export const runtime = 'nodejs';

// 解析弹幕 XML 为 JSON
function parseXmlDanmaku(xmlText: string): Array<{ p: string; m: string; cid: number }> {
  const comments: Array<{ p: string; m: string; cid: number }> = [];

  // 使用正则表达式提取所有 <d> 标签
  const dTagRegex = /<d\s+p="([^"]+)"[^>]*>([^<]*)<\/d>/g;
  let match;

  while ((match = dTagRegex.exec(xmlText)) !== null) {
    const p = match[1];
    const m = match[2];

    // 从 p 属性中提取 cid（弹幕ID）
    const pParts = p.split(',');
    const cid = pParts[7] ? parseInt(pParts[7]) : 0;

    comments.push({
      p,
      m,
      cid,
    });
  }

  return comments;
}

export async function GET(request: NextRequest) {
  try {
    const searchParams = request.nextUrl.searchParams;
    const episodeId = searchParams.get('episodeId');
    const url = searchParams.get('url');

    // 至少需要一个参数
    if (!episodeId && !url) {
      return NextResponse.json(
        {
          count: 0,
          comments: [],
        },
        { status: 400 }
      );
    }

    // 从数据库读取弹幕配置
    const config = await getConfig();
    const { DanmakuApiBase, DanmakuApiToken } = config.SiteConfig;

    // 构建 API URL
    const baseUrl =
      DanmakuApiToken === '87654321'
        ? DanmakuApiBase
        : `${DanmakuApiBase}/${DanmakuApiToken}`;

    let apiUrl: string;

    if (episodeId) {
      // 通过剧集 ID 获取弹幕 - 使用 XML 格式
      apiUrl = `${baseUrl}/api/v2/comment/${episodeId}?format=xml`;
    } else {
      // 通过视频 URL 获取弹幕 - 使用 XML 格式
      apiUrl = `${baseUrl}/api/v2/comment?url=${encodeURIComponent(url!)}&format=xml`;
    }

    const response = await fetch(apiUrl, {
      method: 'GET',
      headers: {
        'Accept': 'application/xml, text/xml',
      },
    });

    if (!response.ok) {
      throw new Error(`HTTP error! status: ${response.status}`);
    }

    // 获取 XML 文本
    const xmlText = await response.text();

    // 解析 XML 为 JSON
    const comments = parseXmlDanmaku(xmlText);

    return NextResponse.json({
      count: comments.length,
      comments,
    });
  } catch (error) {
    console.error('获取弹幕代理错误:', error);
    return NextResponse.json(
      {
        count: 0,
        comments: [],
      },
      { status: 500 }
    );
  }
}