#!/usr/bin/env node
/**
 * 一次性下载字体到 reports/assets/fonts/，让报告完全离线可用
 *
 * 来源：jsdelivr + @fontsource npm 包（字体的 CDN 包装，稳定）
 * - Inter: 英文正文 + 标题（400/700/800/900）
 * - Noto Sans SC: 中文正文 + 标题（400/500/700/900）— chinese-simplified subset
 * - JetBrains Mono: 代码字体（400/700）
 *
 * 所有字体都是 woff2 格式，浏览器原生支持，体积最小。
 * 下载后生成 fonts.css，HTML 用相对路径 `./assets/fonts/fonts.css` 引用。
 */
const fs = require('fs');
const path = require('path');
const https = require('https');

const FONTS_DIR = path.join('reports', 'assets', 'fonts');
fs.mkdirSync(FONTS_DIR, { recursive: true });

// ============================================================
// 字体清单（family + weight + subset）
// ============================================================
const FONTS = [
    // Inter 英文
    { family: 'Inter', pkg: '@fontsource/inter', weight: 400, subset: 'latin', localName: 'inter-400.woff2' },
    { family: 'Inter', pkg: '@fontsource/inter', weight: 500, subset: 'latin', localName: 'inter-500.woff2' },
    { family: 'Inter', pkg: '@fontsource/inter', weight: 600, subset: 'latin', localName: 'inter-600.woff2' },
    { family: 'Inter', pkg: '@fontsource/inter', weight: 700, subset: 'latin', localName: 'inter-700.woff2' },
    { family: 'Inter', pkg: '@fontsource/inter', weight: 800, subset: 'latin', localName: 'inter-800.woff2' },
    { family: 'Inter', pkg: '@fontsource/inter', weight: 900, subset: 'latin', localName: 'inter-900.woff2' },

    // Noto Sans SC 中文（核心字重：400/500/700/900）
    // chinese-simplified subset 包含 ~7000 常用汉字
    { family: 'Noto Sans SC', pkg: '@fontsource/noto-sans-sc', weight: 400, subset: 'chinese-simplified', localName: 'noto-sc-400.woff2' },
    { family: 'Noto Sans SC', pkg: '@fontsource/noto-sans-sc', weight: 500, subset: 'chinese-simplified', localName: 'noto-sc-500.woff2' },
    { family: 'Noto Sans SC', pkg: '@fontsource/noto-sans-sc', weight: 700, subset: 'chinese-simplified', localName: 'noto-sc-700.woff2' },
    { family: 'Noto Sans SC', pkg: '@fontsource/noto-sans-sc', weight: 900, subset: 'chinese-simplified', localName: 'noto-sc-900.woff2' },
    // latin fallback for numbers/English in Chinese font family
    { family: 'Noto Sans SC', pkg: '@fontsource/noto-sans-sc', weight: 400, subset: 'latin', localName: 'noto-sc-latin-400.woff2' },
    { family: 'Noto Sans SC', pkg: '@fontsource/noto-sans-sc', weight: 700, subset: 'latin', localName: 'noto-sc-latin-700.woff2' },
    { family: 'Noto Sans SC', pkg: '@fontsource/noto-sans-sc', weight: 900, subset: 'latin', localName: 'noto-sc-latin-900.woff2' },

    // JetBrains Mono 代码
    { family: 'JetBrains Mono', pkg: '@fontsource/jetbrains-mono', weight: 400, subset: 'latin', localName: 'jetbrains-400.woff2' },
    { family: 'JetBrains Mono', pkg: '@fontsource/jetbrains-mono', weight: 500, subset: 'latin', localName: 'jetbrains-500.woff2' },
    { family: 'JetBrains Mono', pkg: '@fontsource/jetbrains-mono', weight: 700, subset: 'latin', localName: 'jetbrains-700.woff2' },
];

function buildUrl(font) {
    // jsdelivr 对 @fontsource npm 包的路径格式：
    // https://cdn.jsdelivr.net/npm/@fontsource/<name>/files/<name>-<subset>-<weight>-normal.woff2
    const pkgName = font.pkg.replace('@fontsource/', '');
    return `https://cdn.jsdelivr.net/npm/${font.pkg}/files/${pkgName}-${font.subset}-${font.weight}-normal.woff2`;
}

function download(url, dest) {
    return new Promise((resolve, reject) => {
        const doDownload = (u, redirects = 0) => {
            if (redirects > 3) return reject(new Error('too many redirects'));
            https.get(u, (res) => {
                if (res.statusCode >= 300 && res.statusCode < 400 && res.headers.location) {
                    res.resume();
                    return doDownload(res.headers.location, redirects + 1);
                }
                if (res.statusCode !== 200) {
                    res.resume();
                    return reject(new Error(`HTTP ${res.statusCode} for ${u}`));
                }
                const chunks = [];
                res.on('data', (c) => chunks.push(c));
                res.on('end', () => {
                    fs.writeFileSync(dest, Buffer.concat(chunks));
                    resolve(Buffer.concat(chunks).length);
                });
                res.on('error', reject);
            }).on('error', reject);
        };
        doDownload(url);
    });
}

async function main() {
    console.log(`╔═══ 字体离线化：下载 ${FONTS.length} 个 woff2 → ${FONTS_DIR} ═══╗\n`);
    const results = [];
    for (const font of FONTS) {
        const url = buildUrl(font);
        const dest = path.join(FONTS_DIR, font.localName);
        if (fs.existsSync(dest) && fs.statSync(dest).size > 1000) {
            const kb = (fs.statSync(dest).size / 1024).toFixed(0);
            console.log(`  ⏭  ${font.localName.padEnd(26)} 已存在 ${kb}KB`);
            results.push({ ...font, size: fs.statSync(dest).size, ok: true });
            continue;
        }
        try {
            const size = await download(url, dest);
            const kb = (size / 1024).toFixed(0);
            console.log(`  ✅ ${font.localName.padEnd(26)} ${kb}KB`);
            results.push({ ...font, size, ok: true });
        } catch (e) {
            console.log(`  ❌ ${font.localName.padEnd(26)} ${e.message}`);
            results.push({ ...font, ok: false, err: e.message });
        }
    }

    // ============================================================
    // 生成 fonts.css
    // ============================================================
    const okFonts = results.filter((r) => r.ok);
    const cssParts = [
        '/* 本地离线字体 · 由 scripts/tools/setup-fonts.js 自动生成 */',
        '/* 相对路径引用：HTML 文件应放在 reports/ 下，字体在 reports/assets/fonts/ */',
        '',
    ];

    // Inter 的 @font-face（英文基本拉丁）
    const interLatinRange = 'U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+2074, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD';
    for (const f of okFonts.filter((x) => x.family === 'Inter')) {
        cssParts.push(`@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: ${f.weight};
  font-display: swap;
  src: url('./${f.localName}') format('woff2');
  unicode-range: ${interLatinRange};
}`);
    }

    // Noto Sans SC 的 @font-face（中文简体 + 西文拉丁各自 unicode-range）
    const nsLatinRange = 'U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+2074, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD';
    // 中文 + 中日韩符号常用范围
    const nsCnRange = 'U+4E00-9FFF, U+3000-303F, U+FF00-FFEF, U+2E80-2EFF, U+31C0-31EF, U+3200-33FF, U+3400-4DBF';
    for (const f of okFonts.filter((x) => x.family === 'Noto Sans SC')) {
        const range = f.subset === 'latin' ? nsLatinRange : nsCnRange;
        cssParts.push(`@font-face {
  font-family: 'Noto Sans SC';
  font-style: normal;
  font-weight: ${f.weight};
  font-display: swap;
  src: url('./${f.localName}') format('woff2');
  unicode-range: ${range};
}`);
    }

    // JetBrains Mono
    for (const f of okFonts.filter((x) => x.family === 'JetBrains Mono')) {
        cssParts.push(`@font-face {
  font-family: 'JetBrains Mono';
  font-style: normal;
  font-weight: ${f.weight};
  font-display: swap;
  src: url('./${f.localName}') format('woff2');
  unicode-range: ${interLatinRange};
}`);
    }

    const cssPath = path.join(FONTS_DIR, 'fonts.css');
    fs.writeFileSync(cssPath, cssParts.join('\n\n') + '\n', 'utf-8');

    const totalKB = (okFonts.reduce((s, f) => s + f.size, 0) / 1024).toFixed(0);
    console.log(`\n✅ fonts.css → ${cssPath}`);
    console.log(`   字体总量: ${okFonts.length} 个 woff2 · ${totalKB} KB`);
    const failed = results.filter((r) => !r.ok);
    if (failed.length) {
        console.log(`\n⚠ 失败 ${failed.length} 个：`);
        failed.forEach((f) => console.log(`   · ${f.localName}: ${f.err}`));
    }
    console.log(`\n╚═══ 完成。现在可在 HTML 里用 <link href="./assets/fonts/fonts.css"> 引用 ═══╝`);
}

main().catch((e) => { console.error(e); process.exit(1); });