import TurndownService from 'turndown';
import { marked } from 'marked';
/**
* Transform Markdown to HTML for storage in GAS
* Google Apps Script doesn't support .md files, so we convert to HTML
*/
export function transformMarkdownToHTML(content: string, filename: string): { content: string; filename: string } {
// Convert markdown to HTML
const html = marked(content);
// Wrap in basic HTML structure with metadata
const wrappedHTML = `<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<meta name="original-filename" content="${filename}">
<meta name="file-type" content="markdown-to-html">
<title>${filename.replace('.md', '')}</title>
<style>
body { font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif; line-height: 1.6; padding: 20px; max-width: 900px; margin: 0 auto; }
code { background: #f4f4f4; padding: 2px 4px; border-radius: 3px; }
pre { background: #f4f4f4; padding: 10px; border-radius: 5px; overflow-x: auto; }
blockquote { border-left: 4px solid #ddd; margin: 0; padding-left: 20px; color: #666; }
</style>
</head>
<body>
${html}
</body>
</html>`;
return {
content: wrappedHTML,
filename: filename.replace('.md', '.html')
};
}
/**
* Transform HTML back to Markdown when pulling from GAS
*/
export function transformHTMLToMarkdown(content: string, filename: string): { content: string; filename: string } {
// Check if this is a converted markdown file
if (!content.includes('file-type" content="markdown-to-html"')) {
// Not a converted markdown file, return as-is
return { content, filename };
}
// Extract the body content
const bodyMatch = content.match(/<body[^>]*>([\s\S]*?)<\/body>/i);
if (!bodyMatch) {
return { content, filename };
}
// Convert HTML back to Markdown
const turndown = new TurndownService({
headingStyle: 'atx',
codeBlockStyle: 'fenced',
bulletListMarker: '-'
});
// Configure turndown for better code block handling
turndown.addRule('fencedCodeBlock', {
filter: function (node: any) {
return node.nodeName === 'PRE' && node.firstChild?.nodeName === 'CODE';
},
replacement: function (content: string, node: any) {
const codeNode = node.firstChild as HTMLElement;
const lang = codeNode.className.replace('language-', '') || '';
return '\n```' + lang + '\n' + codeNode.textContent + '\n```\n';
}
});
const markdown = turndown.turndown(bodyMatch[1].trim());
return {
content: markdown,
filename: filename.replace('.html', '.md')
};
}
/**
* Transform dotfiles to GAS-compatible modules
* e.g., .gitignore -> _gitignore.gs with content as exported string
*/
export function transformDotfileToModule(content: string, filename: string): { content: string; filename: string } {
// Replace leading dot with underscore for GAS compatibility
const gasFilename = filename.replace(/^\./, '_') + '.gs';
// Escape the content for JavaScript string
const escapedContent = content
.replace(/\\/g, '\\\\')
.replace(/`/g, '\\`')
.replace(/\$/g, '\\$');
// Wrap content as a CommonJS module that exports the original content
const moduleContent = `function _main(
module = globalThis.__getCurrentModule(),
exports = module.exports,
require = globalThis.require
) {
/**
* Original file: ${filename}
* This is a dotfile converted to GAS-compatible format
* The original content is preserved as a string export
*/
const content = \`${escapedContent}\`;
module.exports = {
filename: '${filename}',
type: 'dotfile',
content: content,
// Helper to write back to disk with original filename
getOriginalContent: function() {
return content;
},
// Helper to get original filename
getOriginalFilename: function() {
return '${filename}';
}
};
}
__defineModule__(_main);`;
return {
content: moduleContent,
filename: gasFilename
};
}
/**
* Transform GAS module back to dotfile
*/
export function transformModuleToDotfile(content: string, filename: string): { content: string; filename: string } | null {
// Check if this is a transformed dotfile
if (!filename.startsWith('_') || !filename.endsWith('.gs')) {
return null;
}
// Check if content indicates it's a transformed dotfile
if (!content.includes('type: \'dotfile\'')) {
return null;
}
// Extract the original content from the module
const contentMatch = content.match(/const content = `([\s\S]*?)`;/);
if (!contentMatch) {
return null;
}
// Unescape the content
const unescapedContent = contentMatch[1]
.replace(/\\\$/g, '$')
.replace(/\\`/g, '`')
.replace(/\\\\/g, '\\');
// Restore original filename (replace leading underscore with dot, remove .gs)
const originalFilename = '.' + filename.slice(1, -3);
return {
content: unescapedContent,
filename: originalFilename
};
}
/**
* Wrap JavaScript content as CommonJS module for GAS
*/
export function wrapAsCommonJSModule(content: string, filename: string): string {
// Check if already wrapped
if (content.includes('function _main(') && content.includes('__defineModule__(_main)')) {
return content;
}
// Extract the base name for module documentation
const moduleName = filename.replace(/\.(gs|js)$/, '');
return `function _main(
module = globalThis.__getCurrentModule(),
exports = module.exports,
require = globalThis.require
) {
/**
* Module: ${moduleName}
* Auto-wrapped for GAS CommonJS compatibility
*/
${content.split('\n').map(line => ' ' + line).join('\n')}
}
__defineModule__(_main);`;
}
/**
* Unwrap CommonJS module to get original content
*/
export function unwrapCommonJSModule(content: string): string {
// Check if this is a wrapped module
if (!content.includes('function _main(') || !content.includes('__defineModule__(_main)')) {
return content;
}
// Extract content between function declaration and closing brace
const match = content.match(/function _main\([^)]*\)\s*{([\s\S]*?)}\s*\n\s*__defineModule__\(_main\);?/);
if (!match) {
return content;
}
// Remove the module wrapper and de-indent
const wrappedContent = match[1];
// Remove module documentation comments if present
const cleanContent = wrappedContent
.replace(/^\s*\/\*\*[\s\S]*?\*\/\s*\n/, '')
.split('\n')
.map(line => line.replace(/^ /, '')) // Remove 2-space indent
.join('\n')
.trim();
return cleanContent;
}
/**
* Check if a file needs transformation based on its name
*/
export function needsTransformation(filename: string): boolean {
// Markdown files
if (filename.endsWith('.md')) return true;
// Dotfiles
if (filename.startsWith('.')) return true;
// Already transformed files
if (filename.startsWith('_') && filename.endsWith('.gs')) return true;
if (filename.endsWith('.html') && filename.toLowerCase().includes('readme')) return true;
return false;
}
/**
* Transform a file for GAS storage
*/
export function transformForGAS(content: string, filename: string): { content: string; filename: string } {
// Handle markdown files
if (filename.endsWith('.md')) {
return transformMarkdownToHTML(content, filename);
}
// Handle dotfiles
if (filename.startsWith('.')) {
return transformDotfileToModule(content, filename);
}
// Handle regular JS files - ensure they have CommonJS wrapper
if (filename.endsWith('.js') || filename.endsWith('.gs')) {
return {
content: wrapAsCommonJSModule(content, filename),
filename: filename.endsWith('.js') ? filename.replace('.js', '.gs') : filename
};
}
// No transformation needed
return { content, filename };
}
/**
* Transform a file from GAS storage back to original format
*/
export function transformFromGAS(content: string, filename: string): { content: string; filename: string } {
// Check for transformed dotfiles
const dotfileResult = transformModuleToDotfile(content, filename);
if (dotfileResult) {
return dotfileResult;
}
// Check for markdown HTML files
if (filename.endsWith('.html') && content.includes('file-type" content="markdown-to-html"')) {
return transformHTMLToMarkdown(content, filename);
}
// Unwrap CommonJS modules for local storage
if (filename.endsWith('.gs')) {
return {
content: unwrapCommonJSModule(content),
filename: filename.replace('.gs', '.js')
};
}
// No transformation needed
return { content, filename };
}
/**
* Get the GAS-compatible filename for a given local filename
*/
export function getGASFilename(localFilename: string): string {
if (localFilename.endsWith('.md')) {
return localFilename.replace('.md', '.html');
}
if (localFilename.startsWith('.')) {
return localFilename.replace(/^\./, '_') + '.gs';
}
if (localFilename.endsWith('.js')) {
return localFilename.replace('.js', '.gs');
}
return localFilename;
}
/**
* Get the local filename for a given GAS filename
*/
export function getLocalFilename(gasFilename: string): string {
// Check for transformed dotfiles
if (gasFilename.startsWith('_') && gasFilename.endsWith('.gs')) {
// Could be a dotfile
return '.' + gasFilename.slice(1, -3);
}
// Check for markdown HTML files
if (gasFilename.endsWith('.html') && gasFilename.toLowerCase().includes('readme')) {
return gasFilename.replace('.html', '.md');
}
// Regular GS to JS conversion
if (gasFilename.endsWith('.gs')) {
return gasFilename.replace('.gs', '.js');
}
return gasFilename;
}
