#!/usr/bin/env python3
"""照片入库处理器：把 content/photos/ 下超限图片压缩到站内规范。

为什么存在：gitea web/本地上传的是原图（曾发生 196M/21 张入仓事故，
见 git log aea21c8 的重写说明）；sharp 只派生 dist 缩略图不管仓内体积。
工作流：上传照片到 content/photos/（顺带跑一次 sidecar 生成或手写）后、
git commit 前执行本脚本；幂等，已在规范内的文件原样跳过（零 diff）。

规范与迁移器一致：长边 ≤2400px、JPEG q86（scripts/migrate/photos_migrate.py）。
"""
import sys
from pathlib import Path

PHOTOS = Path("content/photos")
MAX_EDGE = 2400
QUALITY = 86
# 跳过阈值：小于此字节数的 jpg 视为已处理过（2400px q86 成片通常 200KB-1MB）
SKIP_BELOW_BYTES = 1_500_000


def main() -> int:
    from PIL import Image

    changed, skipped = [], 0
    for jpg in sorted(PHOTOS.glob("*.jpg")):
        size = jpg.stat().st_size
        if size < SKIP_BELOW_BYTES:
            skipped += 1
            continue
        STORE = Path.home() / "docker_apps/blog/photos-originals"
        STORE.mkdir(parents=True, exist_ok=True)
        # 压缩覆写仓内文件前原件先进 store（幂等：store 已有同名则跳过）
        if not (STORE / jpg.name).exists():
            (STORE / jpg.name).write_bytes(jpg.read_bytes())
        img = Image.open(jpg)
        # EXIF 显式保留：重存默认剥离会抽走图库参数条的构建期数据源
        exif = img.info.get("exif")
        if img.mode not in ("RGB", "L"):
            img = img.convert("RGB")
        img.thumbnail((MAX_EDGE, MAX_EDGE))
        kwargs = {"exif": exif} if exif else {}
        img.save(jpg, "JPEG", quality=QUALITY, optimize=True, **kwargs)
        changed.append((jpg.name, size, jpg.stat().st_size))

    for name, before, after in changed:
        print(f"  compressed: {name} {before/1e6:.1f}M -> {after/1e6:.2f}M")
    print(f"photos ingest: {len(changed)} compressed, {skipped} skipped (within spec)")
    return 0


if __name__ == "__main__":
    sys.exit(main())