/**
* Markdown conversion service for the StatPearls MCP server
*/
import TurndownService from 'turndown';
import type { ArticleContent, FormatOptions } from '../types/index.js';
/**
* Configures the Turndown service with custom rules for medical content
* @returns Configured Turndown service
*/
function configureTurndown(): TurndownService {
const turndownService = new TurndownService({
headingStyle: 'atx',
codeBlockStyle: 'fenced',
emDelimiter: '*'
});
// Add custom rules for medical content
// Preserve tables
turndownService.addRule('tables', {
filter: ['table'],
replacement: function(content, node) {
// For complex tables, we might want to keep the HTML
// This is a simple implementation that might need enhancement
const tableHtml = (node as HTMLElement).outerHTML;
return '\n\n' + tableHtml + '\n\n';
}
});
// Preserve definition lists which are common in medical content
turndownService.addRule('definitionList', {
filter: ['dl'],
replacement: function(content) {
return '\n\n' + content + '\n\n';
}
});
// Preserve definition terms
turndownService.addRule('definitionTerm', {
filter: ['dt'],
replacement: function(content) {
return '**' + content + '**\n\n';
}
});
// Preserve definition descriptions
turndownService.addRule('definitionDescription', {
filter: ['dd'],
replacement: function(content) {
return content + '\n\n';
}
});
return turndownService;
}
/**
* Converts HTML content to Markdown
* @param html The HTML content to convert
* @returns Markdown content
*/
export function convertToMarkdown(html: string): string {
const turndownService = configureTurndown();
return turndownService.turndown(html);
}
/**
* Generates a table of contents from article sections
* @param content The article content
* @returns Markdown table of contents
*/
function generateTableOfContents(content: ArticleContent): string {
let toc = '## Table of Contents\n\n';
content.sections.forEach(section => {
// Create indentation based on heading level
const indent = ' '.repeat(section.level - 1);
// Create a link-friendly version of the heading
const linkId = section.heading
.toLowerCase()
.replace(/[^\w\s-]/g, '')
.replace(/\s+/g, '-');
toc += `${indent}- [${section.heading}](#${linkId})\n`;
});
return toc + '\n';
}
/**
* Formats the article content as a structured Markdown document
* @param content The filtered article content
* @param options Formatting options
* @returns Formatted Markdown content
*/
export function formatMarkdown(content: ArticleContent, options: FormatOptions = {}): string {
const { includeToc = true, maxLength } = options;
// Start with the title
let markdown = `# ${content.title}\n\n`;
// Add source information
markdown += `*Source: [StatPearls - ${content.title}](${content.url})*\n\n`;
// Add table of contents if requested
if (includeToc) {
markdown += generateTableOfContents(content);
}
// Add each section
content.sections.forEach(section => {
// Create the appropriate heading level
const headingMarkers = '#'.repeat(section.level);
// Add the section heading
markdown += `${headingMarkers} ${section.heading}\n\n`;
// Convert the section content from HTML to Markdown
const sectionContent = convertToMarkdown(section.content);
// Add the section content
markdown += `${sectionContent}\n\n`;
});
// Add a disclaimer
markdown += '---\n\n';
markdown += '*This information is provided by StatPearls, a trusted source of peer-reviewed medical content.*\n';
// Apply length limit if specified
if (maxLength && markdown.length > maxLength) {
markdown = markdown.substring(0, maxLength) + '\n\n*[Content truncated due to length limitations]*';
}
return markdown;
}
