#!/usr/bin/env bun
/**
 * GitHub Trending Projects Fetcher
 *
 * 从GitHub获取trending项目列表
 * 支持每日/每周趋势，按语言筛选
 */

import { $ } from "bun";

interface TrendingProject {
  rank: number;
  name: string;
  description: string;
  language: string;
  stars: string;
  starsThisPeriod: string;
  url: string;
}

interface TrendingOptions {
  period: "daily" | "weekly";
  language?: string;
  limit: number;
}

function buildTrendingUrl(options: TrendingOptions): string {
  const baseUrl = "https://github.com/trending";
  const since = options.period === "daily" ? "daily" : "weekly";
  let url = `${baseUrl}?since=${since}`;
  if (options.language) {
    url += `&language=${encodeURIComponent(options.language.toLowerCase())}`;
  }
  return url;
}

function parseTrendingProjects(html: string, limit: number): TrendingProject[] {
  const projects: TrendingProject[] = [];
  try {
    const articleRegex = /<article[^>]*>([\s\S]*?)<\/article>/g;
    const articles = html.match(articleRegex) || [];
    const articlesToProcess = articles.slice(0, limit);
    articlesToProcess.forEach((article, index) => {
      try {
        const headingMatch = article.match(/<h[12][^>]*>([\s\S]*?)<\/h[12]>/);
        let repoName: string | null = null;
        if (headingMatch) {
          const headingContent = headingMatch[1];
          const validLinkMatch = headingContent.match(
            /<a[^>]*href="\/([^\/"\/]+\/[^\/"\/]+)"[^>]*>(?![^<]*login)/
          );
          if (validLinkMatch) {
            repoName = validLinkMatch[1];
          }
        }
        if (!repoName) {
          const repoMatch = article.match(
            /<a[^>]*href="\/([a-zA-Z0-9_.-]+\/[a-zA-Z0-9_.-]+)"[^>]*>(?!.*(?:login|stargazers|forks|issues))/
          );
          repoName = repoMatch ? repoMatch[1] : null;
        }
        const descMatch = article.match(/<p[^>]*class="[^"]*col-9[^"]*"[^>]*>([\s\S]*?)<\/p>/);
        const description = descMatch
          ? descMatch[1]
              .replace(/<[^>]+>/g, "")
              .replace(/&amp;/g, "&")
              .replace(/&lt;/g, "<")
              .replace(/&gt;/g, ">")
              .replace(/&quot;/g, '"')
              .trim()
              .substring(0, 200)
          : "No description";
        const langMatch = article.match(/<span[^>]*itemprop="programmingLanguage"[^>]*>([^<]+)<\/span>/);
        const language = langMatch ? langMatch[1].trim() : "Unknown";
        const starsMatch = article.match(/<a[^>]*href="\/[^"]+\/stargazers"[^>]*>(\d[\d,]*)\s*stars?/);
        const totalStars = starsMatch ? starsMatch[1] : "0";
        const starsAddedMatch = article.match(/(\d[\d,]*)\s*stars?\s*(?:today|this week)/i);
        const starsAdded = starsAddedMatch ? `+${starsAddedMatch[1]}` : "";
        if (repoName && !repoName.includes("login") && !repoName.includes("return_to")) {
          projects.push({
            rank: index + 1,
            name: repoName,
            description,
            language,
            stars: totalStars,
            starsThisPeriod: starsAdded,
            url: `https://github.com/${repoName}`,
          });
        }
      } catch (error) {
        console.error(`解析第${index + 1}个项目失败:`, error);
      }
    });
  } catch (error) {
    console.error("解析trending项目失败:", error);
  }
  return projects;
}

function formatProjects(projects: TrendingProject[], options: TrendingOptions): string {
  if (projects.length === 0) {
    return "# GitHub Trending - No Projects Found\n\n没有找到trending项目，可能是网络问题或页面结构变化。";
  }
  const periodLabel = options.period === "daily" ? "Daily" : "Weekly";
  const languageLabel = options.language ? `Language: ${options.language}` : "Language: All";
  const today = new Date().toISOString().split("T")[0];
  let output = `# GitHub Trending Projects - ${periodLabel} (${today})\n\n`;
  output += `📊 **Total:** ${projects.length} projects | **${languageLabel}** | **Period:** ${periodLabel}\n\n`;
  output += `---\n\n`;
  projects.forEach((project) => {
    output += `## ${project.rank}. ${project.name} - ⭐ ${project.stars}`;
    if (project.starsThisPeriod) {
      output += ` (${project.starsThisPeriod} this ${options.period})`;
    }
    output += `\n`;
    output += `**Language:** ${project.language}\n`;
    output += `**Description:** ${project.description}\n`;
    output += `**URL:** ${project.url}\n\n`;
  });
  output += `---\n`;
  output += `📊 Data from: https://github.com/trending\n`;
  return output;
}

async function main() {
  const args = process.argv.slice(2);
  let period: "daily" | "weekly" = "weekly";
  let language: string | undefined;
  let limit = 10;
  for (const arg of args) {
    if (arg === "daily" || arg === "weekly") {
      period = arg;
    } else if (arg.startsWith("--language=")) {
      language = arg.split("=")[1];
    } else if (arg.startsWith("-l=")) {
      language = arg.split("=")[1];
    } else if (arg.startsWith("--limit=")) {
      limit = parseInt(arg.split("=")[1]) || 10;
    }
  }
  const options: TrendingOptions = { period, language, limit };
  try {
    const url = buildTrendingUrl(options);
    console.error(`正在获取 GitHub trending 数据: ${url}`);
    const response = await fetch(url);
    if (!response.ok) {
      throw new Error(`HTTP ${response.status}: ${response.statusText}`);
    }
    const html = await response.text();
    const projects = parseTrendingProjects(html, limit);
    const formatted = formatProjects(projects, options);
    console.log(formatted);
    if (projects.length === 0) {
      const debugFile = `/tmp/github-trending-debug-${Date.now()}.html`;
      await Bun.write(debugFile, html);
      console.error(`\n调试: 原始HTML已保存到 ${debugFile}`);
    }
  } catch (error) {
    console.error("❌ 获取trending数据失败:");
    console.error(error);
    process.exit(1);
  }
}

main();