#!/usr/bin/env node
// README 动效资产抓取器（5i T8）：把只能靠外部生成的 SVG 数据卡抓成本地静态文件
// 设计取舍：
//   · 产物入仓（public/github-assets/）→ 构建确定性与离线可构建优先，不在 CI 里跑本脚本
//   · 单资产失败保留旧文件；无旧文件则跳过（组件侧按存在性决定是否渲染该块）
//   · 配色按站点 tokens 近似：透明底 + 文字 #33343a(亮)/#c9ccd4(暗) + 线条 #3454d1
//   · manifest.json 记录来源 URL 与抓取时间（可追溯，不含任何凭据）
// 用法：node scripts/build-perf/fetch-readme-assets.mjs [--force]
import { mkdirSync, writeFileSync, existsSync, readFileSync } from 'node:fs';
import { join } from 'node:path';

const OUT_DIR = 'public/github-assets';
const LOGIN = 'wait4xx';
const TIMEOUT_MS = 10_000;
const UA = 'wait4x-blog-assets/1.0 (+https://wait4x.online)';

// 站点 tokens 近似值（与灰阶纪律一致：底透明，线条单一强调色）
const ACCENT = '3454d1';
const INK_LIGHT = '33343a';
const INK_DARK = 'c9ccd4';
const MUTED_LIGHT = '8b8f98';
const MUTED_DARK = '9aa0aa';

/** 同一张卡按明暗两套参数各存一份（组件内用 CSS 切换，零运行时请求） */
const ASSETS = [
  {
    name: 'stats',
    url: (theme) =>
      `https://github-readme-stats.vercel.app/api?username=${LOGIN}` +
      '&show_icons=true&hide_border=true&include_all_commits=true&count_private=true&rank_icon=github' +
      `&bg_color=00000000&title_color=${ACCENT}&icon_color=${ACCENT}` +
      `&text_color=${theme === 'dark' ? INK_DARK : INK_LIGHT}`,
    label: 'GitHub 统计',
  },
  {
    name: 'top-langs',
    url: (theme) =>
      `https://github-readme-stats.vercel.app/api/top-langs/?username=${LOGIN}` +
      '&layout=compact&hide_border=true&langs_count=6' +
      `&bg_color=00000000&title_color=${ACCENT}` +
      `&text_color=${theme === 'dark' ? INK_DARK : INK_LIGHT}`,
    label: '语言分布',
  },
  {
    name: 'streak',
    url: (theme) =>
      `https://streak-stats.demolab.com/?user=${LOGIN}&hide_border=true` +
      '&background=00000000' +
      `&ring=${ACCENT}&fire=${ACCENT}&currStreakLabel=${ACCENT}` +
      `&currStreakNum=${theme === 'dark' ? INK_DARK : INK_LIGHT}` +
      `&sideNums=${theme === 'dark' ? INK_DARK : INK_LIGHT}` +
      `&sideLabels=${theme === 'dark' ? MUTED_DARK : MUTED_LIGHT}` +
      `&dates=${theme === 'dark' ? MUTED_DARK : MUTED_LIGHT}`,
    label: '连续贡献',
  },
  {
    // 贡献蛇：GitHub Action 生成，配色由 action 侧决定，无法传参 → 只抓一份
    name: 'snake',
    url: () => `https://raw.githubusercontent.com/${LOGIN}/${LOGIN}/output/github-contribution-grid-snake.svg`,
    label: '贡献蛇',
    single: true,
  },
];

/** 10s 超时抓取；返回 SVG 文本或 null */
async function grab(url) {
  try {
    const res = await fetch(url, {
      headers: { 'User-Agent': UA, Accept: 'image/svg+xml,image/*;q=0.8,*/*;q=0.5' },
      signal: AbortSignal.timeout(TIMEOUT_MS),
    });
    if (!res.ok) {
      console.warn(`[assets] HTTP ${res.status}: ${url.slice(0, 90)}…`);
      return null;
    }
    const text = await res.text();
    if (!text.includes('<svg')) {
      console.warn(`[assets] 非 SVG 响应，已跳过: ${url.slice(0, 90)}…`);
      return null;
    }
    return text;
  } catch (err) {
    console.warn(`[assets] 抓取失败（${err.name === 'TimeoutError' ? '超时' : err.message}）: ${url.slice(0, 90)}…`);
    return null;
  }
}

const force = process.argv.includes('--force');
mkdirSync(OUT_DIR, { recursive: true });
const manifestPath = join(OUT_DIR, 'manifest.json');
const manifest = existsSync(manifestPath) ? JSON.parse(readFileSync(manifestPath, 'utf8')) : { assets: {} };
const now = new Date().toISOString();
let ok = 0;
let kept = 0;
let skipped = 0;

for (const asset of ASSETS) {
  const themes = asset.single ? [null] : ['light', 'dark'];
  for (const theme of themes) {
    const fileName = theme ? `${asset.name}-${theme}.svg` : `${asset.name}.svg`;
    const filePath = join(OUT_DIR, fileName);
    const url = asset.url(theme);
    const svg = await grab(url);
    if (svg) {
      writeFileSync(filePath, svg, 'utf8');
      manifest.assets[fileName] = { source: url, fetchedAt: now, label: asset.label, theme: theme ?? 'any' };
      console.log(`[assets] ✓ ${fileName} (${Math.round(svg.length / 1024)}KB)`);
      ok += 1;
    } else if (existsSync(filePath)) {
      console.log(`[assets] ↺ ${fileName} 抓取失败，保留旧文件`);
      kept += 1;
    } else {
      console.warn(`[assets] ⊘ ${fileName} 抓取失败且无旧文件 → 构建时将跳过该块`);
      skipped += 1;
    }
  }
}

writeFileSync(manifestPath, `${JSON.stringify(manifest, null, 2)}\n`, 'utf8');
console.log(`[assets] 完成：新增/更新 ${ok}，保留旧文件 ${kept}，跳过 ${skipped}；manifest → ${manifestPath}`);
process.exit(0);