// build-index.mjs — Node.js utility script
// Scans portraits/ and regenerates portraits/index.json
// Run with: node scripts/build-index.mjs
// (This script is NOT loaded by Foundry — it's a dev tool only.)

import { readdir, writeFile } from 'fs/promises';
import { join, extname, basename, dirname } from 'path';
import { fileURLToPath } from 'url';

const __dirname  = dirname(fileURLToPath(import.meta.url));
const MODULE_DIR = join(__dirname, '..');
const PORTRAITS  = join(MODULE_DIR, 'portraits');
const MODULE_ID  = 'npc-portrait-pack';

// ── Category classification ────────────────────────────────────────────
function classify(filename) {
  const name = basename(filename, '.png');

  // Named NPC: npc_NNNN_description
  if (/^npc_\d+_/.test(name)) {
    const parts = name.split('_');
    const tags  = [];
    let gender  = null;
    for (const p of parts.slice(2)) {
      if (p === 'male' || p === 'female') { gender = p; tags.unshift(p); }
      else if (p === 'elderly')           { tags.push('elderly'); }
      else                                { tags.push(p); }
    }
    return { category: 'named_npc', race: 'human', gender, tags };
  }

  // Race + gender: race_gender_NN
  const rg = name.match(/^(human|ebon|frother|shaktar|stormer|waister|wraith)_(male|female)_\d+$/);
  if (rg) {
    const [, race, gender] = rg;
    return { category: race, race, gender, tags: [gender] };
  }

  if (/^creature_\d+$/.test(name))     return { category: 'creature',      race: 'creature',      gender: null, tags: ['creature'] };
  if (/^mutant_\d+$/.test(name))       return { category: 'creature',      race: 'mutant',        gender: null, tags: ['mutant','creature'] };
  if (/^serial_killer_\d+$/.test(name))return { category: 'serial_killer', race: 'human',         gender: null, tags: ['serial_killer','threat'] };
  if (/^portrait_\d+$/.test(name))     return { category: 'generic',       race: 'human',         gender: null, tags: [] };

  return { category: 'generic', race: 'unknown', gender: null, tags: [] };
}

// ── Main ───────────────────────────────────────────────────────────────
async function buildIndex() {
  const files   = await readdir(PORTRAITS);
  const pngFiles = files.filter(f => extname(f).toLowerCase() === '.png').sort();

  const portraits = pngFiles.map(filename => {
    const id = basename(filename, '.png');
    const { category, race, gender, tags } = classify(filename);
    return {
      id,
      path: `modules/${MODULE_ID}/portraits/${filename}`,
      category,
      race,
      gender,
      tags,
    };
  });

  portraits.sort((a, b) => a.id.localeCompare(b.id));

  const index = { version: '1.0.0', count: portraits.length, portraits };
  const outputPath = join(PORTRAITS, 'index.json');
  await writeFile(outputPath, JSON.stringify(index, null, 2), 'utf-8');

  // Summary
  const cats = portraits.reduce((acc, p) => {
    acc[p.category] = (acc[p.category] ?? 0) + 1;
    return acc;
  }, {});
  console.log(`✓ Built index: ${portraits.length} portraits → ${outputPath}`);
  console.log('\nBy category:');
  for (const [cat, count] of Object.entries(cats).sort()) {
    console.log(`  ${cat.padEnd(15)} ${count}`);
  }
}

buildIndex().catch(err => { console.error('Error:', err); process.exit(1); });