#!/usr/bin/env node

/**
 * Generate output HTML from template + data for space-route documents.
 *
 * Usage: node generate.mjs <docId>
 * Example: node generate.mjs space-route-1
 *
 * Reads:  docs/<docId>.template.html
 * Reads:  docs/<docId>.data.json (optional)
 * Writes: docs/<docId>.output.html
 *
 * data.json format (from space-route editor):
 * {
 *   pages: [{
 *     page: 1,
 *     objects: [{ nodeId, type, src, left, top, w, h, rotate, flipH }],
 *     nodes: [{ nodeId, left, top }]
 *   }]
 * }
 */

import { readFileSync, writeFileSync, existsSync } from 'fs';
import { join, dirname } from 'path';
import { fileURLToPath } from 'url';
import { postGenerate } from '../../../src/scripts/post-generate.mjs';

const __dirname = dirname(fileURLToPath(import.meta.url));
const docsDir = join(__dirname, '..', 'docs');

const docId = process.argv[2];
if (!docId) {
  console.error('Usage: node generate.mjs <docId>');
  process.exit(1);
}

const templatePath = join(docsDir, `${docId}.template.html`);
const dataPath = join(docsDir, `${docId}.data.json`);
const outputPath = join(docsDir, `${docId}.output.html`);

if (!existsSync(templatePath)) {
  console.error(`Template not found: ${templatePath}`);
  process.exit(1);
}

let html = readFileSync(templatePath, 'utf-8');

if (existsSync(dataPath)) {
  const data = JSON.parse(readFileSync(dataPath, 'utf-8'));
  html = applyData(html, data);
  console.log(`Applied data from ${data.pages?.length || 0} pages`);
}

writeFileSync(outputPath, html);
console.log(`Generated: ${outputPath}`);
await postGenerate(outputPath);

function applyData(html, data) {
  if (!data.pages) return html;

  // Split by page divs
  const pageRegex = /<div class="w-\[210mm\] h-\[297mm\]"/g;
  const starts = [];
  let match;
  while ((match = pageRegex.exec(html)) !== null) {
    starts.push(match.index);
  }

  if (starts.length === 0) return html;

  for (let i = data.pages.length - 1; i >= 0; i--) {
    const pageData = data.pages[i];
    const pageNum = pageData.page || (i + 1);
    const pageIdx = pageNum - 1;

    if (pageIdx >= starts.length) continue;

    const pageStart = starts[pageIdx];
    const pageEnd = pageIdx + 1 < starts.length ? starts[pageIdx + 1] : html.length;
    let pageHtml = html.slice(pageStart, pageEnd);

    // Apply object positions
    if (pageData.objects) {
      for (const obj of pageData.objects) {
        pageHtml = applyObject(pageHtml, obj);
      }
    }

    // Apply node positions and update edges
    if (pageData.nodes) {
      for (const node of pageData.nodes) {
        pageHtml = applyNode(pageHtml, node);
      }
    }

    html = html.slice(0, pageStart) + pageHtml + html.slice(pageEnd);
  }

  return html;
}

function applyObject(pageHtml, obj) {
  // Match: <img class="space-obj" data-node-id="N" data-type="..." style="..."
  const nodeId = obj.nodeId;
  const regex = new RegExp(
    `(<img class="space-obj"[^>]*data-node-id="${nodeId}"[^>]*style=")([^"]*)(")`
  );

  return pageHtml.replace(regex, (match, prefix, oldStyle, suffix) => {
    const parts = [];
    parts.push(`left: ${obj.left}`);
    parts.push(`top: ${obj.top}`);
    if (obj.w) parts.push(`width: ${obj.w}`);
    if (obj.h) parts.push(`height: ${obj.h}`);

    const transforms = [];
    if (obj.rotate) transforms.push(`rotate(${obj.rotate}deg)`);
    if (obj.flipH) transforms.push('scaleX(-1)');
    if (transforms.length) parts.push(`transform: ${transforms.join(' ')}`);

    // Preserve margin if present in old style
    const marginMatch = oldStyle.match(/margin[^;]+;/);
    if (marginMatch) parts.push(marginMatch[0].replace(/;$/, ''));

    return prefix + parts.join('; ') + ';' + suffix;
  });
}

function applyNode(pageHtml, node) {
  // Update node div position
  const nodeRegex = new RegExp(
    `(<div[^>]*data-node-id="${node.nodeId}"[^>]*style=")([^"]*)(")`
  );

  pageHtml = pageHtml.replace(nodeRegex, (match, prefix, oldStyle, suffix) => {
    const newStyle = oldStyle
      .replace(/left:\s*[^;]+/, `left: ${node.left}`)
      .replace(/top:\s*[^;]+/, `top: ${node.top}`);
    return prefix + newStyle + suffix;
  });

  // Update edges connected to this node
  const leftMm = parseFloat(node.left);
  const topMm = parseFloat(node.top);

  // Edges where this node is first: <line data-edge="N-M" x1="..." y1="..."
  const edgeRegex1 = new RegExp(
    `(<line[^>]*data-edge="${node.nodeId}-\\d+"[^>]*)(x1=")[^"]*("\\s*y1=")[^"]*(")`,'g'
  );
  pageHtml = pageHtml.replace(edgeRegex1, (match, prefix, x1p, y1p, suffix) => {
    return `${prefix}${x1p}${leftMm}mm${y1p}${topMm}mm${suffix}`;
  });

  // Edges where this node is second: <line data-edge="M-N" ... x2="..." y2="..."
  const edgeRegex2 = new RegExp(
    `(<line[^>]*data-edge="\\d+-${node.nodeId}"[^>]*)(x2=")[^"]*("\\s*y2=")[^"]*(")`,'g'
  );
  pageHtml = pageHtml.replace(edgeRegex2, (match, prefix, x2p, y2p, suffix) => {
    return `${prefix}${x2p}${leftMm}mm${y2p}${topMm}mm${suffix}`;
  });

  return pageHtml;
}