import { readdir, readFile, mkdir } from 'node:fs/promises'; import { join, resolve } from 'node:path'; import { Marked } from 'marked'; import puppeteer from 'puppeteer'; const SPECS_DIR = resolve('specs'); const DIST_DIR = resolve('dist'); const OUTPUT_FILE = join(DIST_DIR, 'house-spec.pdf'); async function loadSpecs(): Promise<{ filename: string; content: string }[]> { const files = await readdir(SPECS_DIR); const mdFiles = files.filter(f => f.endsWith('.md')).sort(); const specs: { filename: string; content: string }[] = []; for (const file of mdFiles) { const content = await readFile(join(SPECS_DIR, file), 'utf-8'); specs.push({ filename: file, content }); } return specs; } function buildHtml(bodyHtml: string): string { return `

House Specification

Baufritz Build — Clean Air System

maintainable.xyz

Generated: ${new Date().toISOString().split('T')[0]}

Version 1.0

${bodyHtml} `; } /** * Extract mermaid code blocks from markdown, replacing them with unique * placeholders. Returns the cleaned markdown and a map of placeholder → diagram. * This prevents `marked` from corrupting the mermaid syntax (e.g. turning * indented lines into 
 blocks or mangling special characters).
 */
function extractMermaidBlocks(markdown: string): {
  markdown: string;
  diagrams: Map;
} {
  const diagrams = new Map();
  let index = 0;
  const cleaned = markdown.replace(
    /```mermaid\n([\s\S]*?)```/g,
    (_match, diagram: string) => {
      const id = `MERMAIDPLACEHOLDER${index++}END`;
      diagrams.set(id, diagram.trim());
      return id;
    },
  );
  return { markdown: cleaned, diagrams };
}

/**
 * Re-inject mermaid diagrams into the HTML, replacing placeholders
 * with 
 blocks containing the raw diagram source.
 */
function injectMermaidBlocks(html: string, diagrams: Map): string {
  let result = html;
  for (const [id, diagram] of diagrams) {
    // marked may have wrapped the placeholder in a 
 tag
    const wrappedPattern = new RegExp(`
${id}
`, 'g');
    const rawPattern = new RegExp(id, 'g');
    const replacement = `
\n${diagram}\n
`;
    result = result.replace(wrappedPattern, replacement);
    result = result.replace(rawPattern, replacement);
  }
  return result;
}

async function main() {
  console.log('Loading specs...');
  const specs = await loadSpecs();
  console.log(`Found ${specs.length} spec files.`);

  // Combine specs into raw markdown first
  let rawCombined = specs
    .map((spec, i) => {
      const sectionClass = i === 0 ? 'spec-section first' : 'spec-section';
      return `
\n\n${spec.content}\n\n
`;
    })
    .join('\n\n');

  // Extract all mermaid blocks from the combined markdown (single pass, unique IDs)
  const { markdown: combinedMarkdown, diagrams: allDiagrams } = extractMermaidBlocks(rawCombined);
  console.log(`Extracted ${allDiagrams.size} mermaid diagrams.`);

  // Parse markdown to HTML — mermaid blocks are now just placeholder strings
  const marked = new Marked();
  let bodyHtml = await marked.parse(combinedMarkdown);

  // Re-inject raw mermaid diagrams into the HTML
  bodyHtml = injectMermaidBlocks(bodyHtml, allDiagrams);

  const fullHtml = buildHtml(bodyHtml);

  // Ensure dist directory exists
  await mkdir(DIST_DIR, { recursive: true });

  // Write intermediate HTML for debugging
  const htmlPath = join(DIST_DIR, 'house-spec.html');
  const { writeFile } = await import('node:fs/promises');
  await writeFile(htmlPath, fullHtml, 'utf-8');
  console.log(`HTML written to: ${htmlPath}`);

  // Launch puppeteer and render PDF
  console.log('Launching browser...');
  const browser = await puppeteer.launch({
    headless: true,
    args: ['--no-sandbox', '--disable-setuid-sandbox'],
  });

  const page = await browser.newPage();

  // Set content and wait for mermaid to render
  await page.setContent(fullHtml, { waitUntil: 'networkidle0' });

  // Wait for mermaid diagrams to render
  await page.evaluate(async () => {
    // Check if mermaid is loaded
    if (typeof (window as any).mermaid !== 'undefined') {
      await (window as any).mermaid.run();
    }
  });

  // Small delay to ensure all SVGs are rendered
  await new Promise(resolve => setTimeout(resolve, 2000));

  console.log('Generating PDF...');
  await page.pdf({
    path: OUTPUT_FILE,
    format: 'A4',
    printBackground: true,
    margin: {
      top: '20mm',
      bottom: '20mm',
      left: '18mm',
      right: '18mm',
    },
    displayHeaderFooter: true,
    headerTemplate: `
      

        maintainable.xyz — House Specification
        Baufritz Build
      
`,
    footerTemplate: `
      

         / 
      
`,
  });

  await browser.close();

  console.log(`PDF generated: ${OUTPUT_FILE}`);
}

main().catch(err => {
  console.error('Build failed:', err);
  process.exit(1);
});