"""Transcode les AVIF q98 des visualisations en AVIF q60 (one-shot).

Usage (dans le conteneur, volume output monté) :
    python3 /tmp/transcode_q60.py [--quality 60] [--workers N]

Ne remplace un fichier que si la version q60 est plus légère (garde-fou).
"""
import sys
import os
from pathlib import Path
from concurrent.futures import ProcessPoolExecutor

from PIL import Image

QUALITY = int(sys.argv[sys.argv.index('--quality') + 1]) if '--quality' in sys.argv else 60
WORKERS = int(sys.argv[sys.argv.index('--workers') + 1]) if '--workers' in sys.argv else (os.cpu_count() or 4)
ROOT = Path('/data/output/visualisations')


def transcode(path):
    try:
        before = path.stat().st_size
        img = Image.open(path)
        img.load()
        tmp = path.with_name(path.name + '.q60.tmp.avif')
        img.save(tmp, format='AVIF', quality=QUALITY)
        after = tmp.stat().st_size
        if after < before:
            os.replace(tmp, path)
            return (path.name, before, after, 'remplacé')
        tmp.unlink()
        return (path.name, before, after, 'conservé (q60 plus lourd)')
    except Exception as exc:  # noqa: BLE001
        return (path.name, 0, 0, f'ERREUR {exc}')


if __name__ == '__main__':
    files = sorted(ROOT.rglob('*.avif'))
    files = [f for f in files if '.q60.tmp' not in f.name]
    print(f'{len(files)} AVIF à transcoder en q{QUALITY}, {WORKERS} workers', flush=True)
    total_before = total_after = n_ok = 0
    with ProcessPoolExecutor(max_workers=WORKERS) as pool:
        for i, (name, before, after, status) in enumerate(pool.map(transcode, files), 1):
            total_before += before
            total_after += min(before, after)
            if status.startswith('remplacé'):
                n_ok += 1
            if i % 50 == 0 or i == len(files):
                print(f'  {i}/{len(files)} — {n_ok} remplacés — '
                      f'{total_before / 2**30:.1f} → {total_after / 2**30:.1f} Gio', flush=True)
            elif status.startswith('ERREUR'):
                print(f'  {name}: {status}', flush=True)
    print(f'FIN: {total_before / 2**30:.1f} → {total_after / 2**30:.1f} Gio '
          f'({n_ok} fichiers réencodés)', flush=True)