/**
 * Regenerate all painting thumbnails from their full-size local files.
 * Fixes mismatches where Commons/Wikipedia thumb URLs pointed to the wrong work.
 */
const fs = require('fs');
const path = require('path');
const sharp = require('sharp');
const pool = require('../server/db');
const { generateThumbnailFromFull } = require('./image-fetcher');
const { printCliResult } = require('./lib/cli-result');

const IMAGE_DIR = path.resolve(process.env.IMAGE_DIR || './data/images');

function safeBase(artistName, title) {
  return `${artistName}_${title}`.replace(/[^a-zA-Z0-9_-]/g, '_');
}

function localPath(rel) {
  return path.join(IMAGE_DIR, rel);
}

async function aspectRatio(filePath) {
  const meta = await sharp(filePath).metadata();
  if (!meta.width || !meta.height) return null;
  return meta.width / meta.height;
}

(async () => {
  const rows = await pool.query(
    `SELECT p.id, p.title, p.image_path, p.thumbnail_path, a.name AS artist_name
     FROM paintings p
     JOIN artists a ON a.id = p.artist_id
     WHERE p.image_path IS NOT NULL AND p.image_path <> ''
     ORDER BY p.id`
  );

  let regenerated = 0;
  let skipped = 0;
  let mismatchesBefore = 0;
  const errors = [];

  for (const row of rows.rows) {
    const fullPath = localPath(row.image_path);
    if (!fs.existsSync(fullPath)) {
      skipped++;
      continue;
    }

    const base = safeBase(row.artist_name, row.title);
    const thumbRel = `paintings/thumbs/${base}_thumb.jpg`;
    const thumbPath = localPath(thumbRel);

    if (row.thumbnail_path && fs.existsSync(localPath(row.thumbnail_path))) {
      try {
        const [fullAr, thumbAr] = await Promise.all([
          aspectRatio(fullPath),
          aspectRatio(localPath(row.thumbnail_path)),
        ]);
        if (fullAr && thumbAr && Math.abs(fullAr - thumbAr) / fullAr > 0.15) {
          mismatchesBefore++;
        }
      } catch {
        mismatchesBefore++;
      }
    }

    try {
      if (fs.existsSync(thumbPath)) fs.unlinkSync(thumbPath);
      if (
        row.thumbnail_path &&
        row.thumbnail_path !== thumbRel &&
        fs.existsSync(localPath(row.thumbnail_path))
      ) {
        fs.unlinkSync(localPath(row.thumbnail_path));
      }

      await generateThumbnailFromFull(fullPath, thumbPath);
      await pool.query(`UPDATE paintings SET thumbnail_path = $1 WHERE id = $2`, [thumbRel, row.id]);
      regenerated++;
    } catch (err) {
      errors.push({ id: row.id, title: row.title, error: err.message });
    }
  }

  console.log('Paintings with full image path:', rows.rows.length);
  console.log('Thumbnails regenerated:', regenerated);
  console.log('Skipped (full file missing):', skipped);
  console.log('Aspect-ratio mismatches before fix:', mismatchesBefore);
  if (errors.length) {
    console.log('Errors:', errors.length);
    errors.slice(0, 20).forEach((e) => console.log(`  #${e.id} ${e.title}: ${e.error}`));
  }

  await pool.end();

  if (errors.length) {
    printCliResult({
      script: 'regenerate-thumbnails',
      ok: false,
      summary: `Painting thumbnail regeneration finished with ${errors.length} error(s).`,
      details: [
        `Regenerated: ${regenerated}, skipped: ${skipped}`,
        ...errors.slice(0, 5).map((e) => `  #${e.id} ${e.title}: ${e.error}`),
      ],
    });
  }

  printCliResult({
    script: 'regenerate-thumbnails',
    ok: true,
    summary: 'Painting thumbnail regeneration complete.',
    details: [
      `Regenerated: ${regenerated}, skipped: ${skipped}`,
      `Aspect-ratio mismatches before fix: ${mismatchesBefore}`,
    ],
  });
})().catch((err) => {
  console.error(err);
  printCliResult({
    script: 'regenerate-thumbnails',
    ok: false,
    summary: err.message || String(err),
  });
});