#!/usr/bin/env node

const fs = require('fs');
const path = require('path');
const { execSync } = require('child_process');
const { marked } = require('marked');

// Custom script to handle Mermaid rendering and fix internal links
async function convertMarkdownToPDF() {
    const inputFile = process.argv[2] || 'complete-documentation.md';
    const outputFile = inputFile.replace('.md', '.pdf');
    
    console.log(`Converting ${inputFile} to PDF with Mermaid support...`);
    
    try {
        // Read the markdown file
        let content = fs.readFileSync(`/app/docs/${inputFile}`, 'utf8');
        
        // Remove YAML front matter if present
        content = content.replace(/^---\n[\s\S]*?\n---\n/, '');
        
        // Remove emojis that don't render well in PDF
        content = content.replace(/📋|🛠️|🔧|📊|🏗️|🎉|✅|❌|🚀|📝|📚|🔍|⚠️|💡/g, '');
        
        // Helper function to generate section ID from text
        function generateSectionId(text) {
            return text
                .toLowerCase()
                .replace(/[^\w\s-]/g, '') // Remove special chars
                .replace(/\s+/g, '-')     // Replace spaces with hyphens
                .replace(/-+/g, '-')      // Collapse multiple hyphens
                .replace(/^-|-$/g, '');   // Remove leading/trailing hyphens
        }
        
        // Fix internal links to work within the same document
        // Convert [text](filename.md) to [text](#section-name)
        let linkCount = 0;
        content = content.replace(/\[([^\]]+)\]\((\d+-[^)]+\.md)\)/g, (match, linkText, filename) => {
            // Use the link text to generate the section ID (since that's what the header will be)
            const sectionId = generateSectionId(linkText);
            linkCount++;
            return `[${linkText}](#${sectionId})`;
        });
        
        // Fix relative links ./filename.md
        content = content.replace(/\[([^\]]+)\]\(\.\/(\d+-[^)]+\.md)\)/g, (match, linkText, filename) => {
            const sectionId = generateSectionId(linkText);
            linkCount++;
            return `[${linkText}](#${sectionId})`;
        });
        
        console.log(`✅ Processed ${linkCount} internal links`);
        
        // Process Mermaid diagrams
        let mermaidCounter = 0;
        content = content.replace(/```mermaid\n([\s\S]*?)\n```/g, (match, mermaidCode) => {
            mermaidCounter++;
            const diagramFile = `/app/docs/diagram-${mermaidCounter}.mmd`;
            const imageFile = `/app/docs/diagram-${mermaidCounter}.png`;
            
            // Write mermaid code to temporary file
            fs.writeFileSync(diagramFile, mermaidCode.trim());
            
            try {
                // Generate PNG from mermaid
                execSync(`mmdc -i ${diagramFile} -o ${imageFile} -w 800 -H 600 --backgroundColor white`);
                
                // Replace with image reference
                return `![Diagram ${mermaidCounter}](diagram-${mermaidCounter}.png)`;
            } catch (error) {
                console.warn(`Warning: Failed to render Mermaid diagram ${mermaidCounter}:`, error.message);
                // Return original code block if mermaid fails
                return match;
            }
        });
        
        // Configure marked to generate proper IDs for headers
        marked.use({
            renderer: {
                heading(text, level) {
                    // Generate ID from text content
                    const id = text
                        .toLowerCase()
                        .replace(/[^\w\s-]/g, '') // Remove special chars
                        .replace(/\s+/g, '-')     // Replace spaces with hyphens
                        .replace(/-+/g, '-')      // Collapse multiple hyphens
                        .replace(/^-|-$/g, '');   // Remove leading/trailing hyphens
                    
                    return `<h${level} id="${id}">${text}</h${level}>`;
                }
            }
        });
        
        // Convert markdown to HTML
        const html = marked(content, {
            gfm: true,
            breaks: false,
            headerIds: true,
            mangle: false
        });
        
        // Create complete HTML document with CSS
        const cssContent = fs.readFileSync('/app/docs/custom-styles.css', 'utf8');
        const fullHtml = `
<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <title>DoczyAI Documentation</title>
    <style>
        ${cssContent}
        body { margin: 0; padding: 20px; }
        @page { margin: 2cm; }
    </style>
</head>
<body>
    ${html}
</body>
</html>`;
        
        // Write HTML to temporary file
        const htmlFile = `/app/docs/temp-${inputFile.replace('.md', '.html')}`;
        fs.writeFileSync(htmlFile, fullHtml);
        
        // Use Chromium to generate PDF with clickable links (suppress stderr)
        execSync(`/usr/bin/chromium-browser --headless --disable-gpu --no-sandbox --run-all-compositor-stages-before-draw --virtual-time-budget=10000 --print-to-pdf=/app/docs/${outputFile} --print-to-pdf-no-header file://${htmlFile} 2>/dev/null`);
        
        console.log(`✅ PDF generated: ${outputFile}`);
        
        // Clean up temporary files
        try {
            fs.unlinkSync(htmlFile);
            for (let i = 1; i <= mermaidCounter; i++) {
                try {
                    fs.unlinkSync(`/app/docs/diagram-${i}.mmd`);
                    // Keep PNG files for debugging, remove in production
                    // fs.unlinkSync(`/app/docs/diagram-${i}.png`);
                } catch (e) {
                    // Ignore cleanup errors
                }
            }
        } catch (e) {
            // Ignore cleanup errors
        }
        
    } catch (error) {
        console.error('❌ Error converting to PDF:', error.message);
        console.error(error.stack);
        process.exit(1);
    }
}

convertMarkdownToPDF();