1import fs from "node:fs";
2import os from "node:os";
3import path from "node:path";
4import process from "node:process";
5 
6import {
7  COLOR_PRESETS,
8  FONT_FAMILY_MAP,
9  FONT_SIZE_OPTIONS,
10  THEME_NAMES,
11  extractSummaryFromBody,
12  extractTitleFromMarkdown,
13  formatTimestamp,
14  parseArgs,
15  parseFrontmatter,
16  renderMarkdownDocument,
17  replaceMarkdownImagesWithPlaceholders,
18  resolveContentImages,
19  serializeFrontmatter,
20  stripWrappingQuotes,
21} from "baoyu-md";
22import type { CliOptions } from "baoyu-md";
23 
24interface ImageInfo {
25  placeholder: string;
26  localPath: string;
27  originalPath: string;
28}
29 
30interface ParsedResult {
31  title: string;
32  author: string;
33  summary: string;
34  htmlPath: string;
35  backupPath?: string;
36  contentImages: ImageInfo[];
37}
38 
39type ConvertMarkdownOptions = Partial<Omit<CliOptions, "inputPath">> & {
40  title?: string;
41};
42 
43export async function convertMarkdown(
44  markdownPath: string,
45  options?: ConvertMarkdownOptions,
46): Promise<ParsedResult> {
47  const baseDir = path.dirname(markdownPath);
48  const content = fs.readFileSync(markdownPath, "utf-8");
49  const theme = options?.theme;
50  const keepTitle = options?.keepTitle ?? false;
51  const citeStatus = options?.citeStatus ?? false;
52 
53  const { frontmatter, body } = parseFrontmatter(content);
54 
55  let title = stripWrappingQuotes(options?.title ?? "")
56    || stripWrappingQuotes(frontmatter.title ?? "")
57    || extractTitleFromMarkdown(body);
58  if (!title) {
59    title = path.basename(markdownPath, path.extname(markdownPath));
60  }
61 
62  const author = stripWrappingQuotes(frontmatter.author ?? "");
63  let summary = stripWrappingQuotes(frontmatter.description ?? "")
64    || stripWrappingQuotes(frontmatter.summary ?? "");
65  if (!summary) {
66    summary = extractSummaryFromBody(body, 120);
67  }
68 
69  const effectiveFrontmatter = options?.title
70    ? { ...frontmatter, title }
71    : frontmatter;
72 
73  const { images, markdown: rewrittenBody } = replaceMarkdownImagesWithPlaceholders(
74    body,
75    "MDTOHTMLIMGPH_",
76  );
77  const rewrittenMarkdown = `${serializeFrontmatter(effectiveFrontmatter)}${rewrittenBody}`;
78 
79  console.error(
80    `[markdown-to-html] Rendering with theme: ${theme ?? "default"}, keepTitle: ${keepTitle}, citeStatus: ${citeStatus}`,
81  );
82 
83  const { html } = await renderMarkdownDocument(rewrittenMarkdown, {
84    codeTheme: options?.codeTheme,
85    countStatus: options?.countStatus,
86    citeStatus,
87    defaultTitle: title,
88    fontFamily: options?.fontFamily,
89    fontSize: options?.fontSize,
90    isMacCodeBlock: options?.isMacCodeBlock,
91    isShowLineNumber: options?.isShowLineNumber,
92    keepTitle,
93    legend: options?.legend,
94    primaryColor: options?.primaryColor,
95    theme,
96  });
97 
98  const finalHtmlPath = markdownPath.replace(/\.md$/i, ".html");
99  let backupPath: string | undefined;
100 
101  if (fs.existsSync(finalHtmlPath)) {
102    backupPath = `${finalHtmlPath}.bak-${formatTimestamp()}`;
103    console.error(`[markdown-to-html] Backing up existing file to: ${backupPath}`);
104    fs.renameSync(finalHtmlPath, backupPath);
105  }
106 
107  fs.writeFileSync(finalHtmlPath, html, "utf-8");
108 
109  const hasRemoteImages = images.some((image) =>
110    image.originalPath.startsWith("http://") || image.originalPath.startsWith("https://"),
111  );
112  const tempDir = hasRemoteImages
113    ? fs.mkdtempSync(path.join(os.tmpdir(), "markdown-to-html-"))
114    : baseDir;
115  const contentImages = await resolveContentImages(images, baseDir, tempDir, "markdown-to-html");
116 
117  let finalContent = fs.readFileSync(finalHtmlPath, "utf-8");
118  for (const image of contentImages) {
119    const imgTag = `<img src="${image.originalPath}" data-local-path="${image.localPath}" style="display: block; width: 100%; margin: 1.5em auto;">`;
120    finalContent = finalContent.replace(image.placeholder, imgTag);
121  }
122  fs.writeFileSync(finalHtmlPath, finalContent, "utf-8");
123 
124  console.error(`[markdown-to-html] HTML saved to: ${finalHtmlPath}`);
125 
126  return {
127    title,
128    author,
129    summary,
130    htmlPath: finalHtmlPath,
131    backupPath,
132    contentImages,
133  };
134}
135 
136function printUsage(exitCode = 0): never {
137  const colorNames = Object.keys(COLOR_PRESETS).join(", ");
138  const fontFamilyNames = Object.keys(FONT_FAMILY_MAP).join(", ");
139 
140  console.log(`Convert Markdown to styled HTML
141 
142Usage:
143  npx -y bun main.ts <markdown_file> [options]
144 
145Options:
146  --title <title>         Override title
147  --theme <name>          Theme name (${THEME_NAMES.join(", ")}). Default: default
148  --color <name|hex>      Primary color: ${colorNames}
149  --font-family <name>    Font: ${fontFamilyNames}, or CSS value
150  --font-size <N>         Font size: ${FONT_SIZE_OPTIONS.join(", ")} (default: 16px)
151  --code-theme <name>     Code highlight theme (default: github)
152  --mac-code-block        Show Mac-style code block header
153  --no-mac-code-block     Hide Mac-style code block header
154  --line-number           Show line numbers in code blocks
155  --cite                  Convert ordinary external links to bottom citations. Default: off
156  --count                 Show reading time / word count
157  --legend <value>        Image caption: title-alt, alt-title, title, alt, none
158  --keep-title            Keep the first heading in content. Default: false (removed)
159  --help                  Show this help
160 
161Output:
162  HTML file saved to same directory as input markdown file.
163  Example: article.md -> article.html
164 
165  If HTML file already exists, it will be backed up first:
166  article.html -> article.html.bak-YYYYMMDDHHMMSS
167 
168Output JSON format:
169{
170  "title": "Article Title",
171  "htmlPath": "/path/to/article.html",
172  "backupPath": "/path/to/article.html.bak-20260128180000",
173  "contentImages": [...]
174}
175 
176Example:
177  npx -y bun main.ts article.md
178  npx -y bun main.ts article.md --theme grace
179  npx -y bun main.ts article.md --theme modern --color red
180  npx -y bun main.ts article.md --cite
181`);
182  process.exit(exitCode);
183}
184 
185function parseArgValue(argv: string[], i: number, flag: string): string | null {
186  const arg = argv[i]!;
187  if (arg.includes("=")) {
188    return arg.slice(flag.length + 1);
189  }
190  const next = argv[i + 1];
191  return next ?? null;
192}
193 
194function extractTitleArg(argv: string[]): { renderArgs: string[]; title?: string } {
195  let title: string | undefined;
196  const renderArgs: string[] = [];
197 
198  for (let i = 0; i < argv.length; i += 1) {
199    const arg = argv[i]!;
200    if (arg === "--title" || arg.startsWith("--title=")) {
201      const value = parseArgValue(argv, i, "--title");
202      if (!value) {
203        console.error("Missing value for --title");
204        printUsage(1);
205      }
206      title = value;
207      if (!arg.includes("=")) {
208        i += 1;
209      }
210      continue;
211    }
212    renderArgs.push(arg);
213  }
214 
215  return { renderArgs, title };
216}
217 
218async function main(): Promise<void> {
219  const args = process.argv.slice(2);
220  if (args.length === 0 || args.includes("--help") || args.includes("-h")) {
221    printUsage(0);
222  }
223 
224  const { renderArgs, title } = extractTitleArg(args);
225  const options = parseArgs(renderArgs);
226  if (!options) {
227    printUsage(1);
228  }
229 
230  const markdownPath = path.resolve(process.cwd(), options.inputPath);
231  if (!markdownPath.toLowerCase().endsWith(".md")) {
232    console.error("Input file must end with .md");
233    process.exit(1);
234  }
235 
236  if (!fs.existsSync(markdownPath)) {
237    console.error(`Error: File not found: ${markdownPath}`);
238    process.exit(1);
239  }
240 
241  const result = await convertMarkdown(markdownPath, { ...options, title });
242  console.log(JSON.stringify(result, null, 2));
243}
244 
245await main().catch((error) => {
246  console.error(`Error: ${error instanceof Error ? error.message : String(error)}`);
247  process.exit(1);
248});
249