#!/usr/bin/env python3
"""Download the reviewed artwork manifest, preserving aspect ratio, as local WebP.
Requires Pillow. Existing valid files are reused; failed downloads never replace files.
"""
import argparse
from concurrent.futures import ThreadPoolExecutor
import io
import json
from pathlib import Path
import time
import urllib.request
from PIL import Image, ImageOps

ROOT = Path(__file__).resolve().parents[1]

def download(row):
    target = ROOT / 'static' / row['path'].lstrip('/')
    if target.exists():
        with Image.open(target) as img:
            if img.format == 'WEBP':
                return row['id'], None
    for attempt in range(3):
        try:
            request = urllib.request.Request(row['url'], headers={'User-Agent': 'PersonalGameJournal/1.0 (image catalog)'})
            with urllib.request.urlopen(request, timeout=45) as response:
                content = response.read()
            with Image.open(io.BytesIO(content)) as image:
                image = ImageOps.exif_transpose(image).convert('RGBA')
                image.thumbnail((row.get('maxSize', 800),) * 2, Image.Resampling.LANCZOS)
                target.parent.mkdir(parents=True, exist_ok=True)
                temporary = target.with_suffix('.tmp')
                image.save(temporary, format='WEBP', lossless=row.get('lossless', False), quality=88, method=6)
                temporary.replace(target)
            return row['id'], None
        except Exception as error:
            if attempt == 2:
                return row['id'], str(error)
            time.sleep(attempt + 1)

def main():
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument('--filter', default='')
    parser.add_argument('--workers', type=int, default=6)
    args = parser.parse_args()
    rows = json.loads((ROOT / 'data/game-images.json').read_text())
    rows = [r for r in rows if args.filter in r['id']]
    failed = []
    with ThreadPoolExecutor(max_workers=args.workers) as pool:
        for index, (name, error) in enumerate(pool.map(download, rows), 1):
            if error:
                failed.append((name, error))
                print('FAILED', name, error, flush=True)
            elif index % 100 == 0 or len(rows) < 100:
                print(f'{index}/{len(rows)} {name}', flush=True)
    print(f'{len(rows) - len(failed)}/{len(rows)} images ready', flush=True)
    if failed:
        raise SystemExit(1)

if __name__ == '__main__':
    main()