"""清理数据库中文件已不存在的孤儿记录。

video_scanner 入库后，如果录像文件被手动删除或被 dedup_cleanup 清理，
数据库里的 videos/events 记录不会自动消失，导致：
- analyze.py 对不存在的文件跑分析，全部失败或产生空结果
- webapp 点击播放 404
- 统计数据虚高

本脚本扫描 videos 表，删除 file_path 不存在的记录及其关联 events，
并同步清理孤儿缩略图文件。执行前请确保已备份 analysis.db。
"""
import os
import sqlite3

from analysis.config import PROJECT_ROOT, THUMBNAILS_DIR, DB_PATH


def cleanup_orphans(dry_run=True):
    conn = sqlite3.connect(str(DB_PATH))
    conn.row_factory = sqlite3.Row

    videos = conn.execute("SELECT id, file_path, status FROM videos").fetchall()
    to_delete = []
    for v in videos:
        full_path = PROJECT_ROOT / v["file_path"]
        if not full_path.exists():
            to_delete.append(v)

    print(f"videos 总数: {len(videos)}")
    print(f"文件不存在的孤儿记录: {len(to_delete)}")

    # 按状态统计
    by_status = {}
    for v in to_delete:
        by_status[v["status"]] = by_status.get(v["status"], 0) + 1
    for status, cnt in sorted(by_status.items(), key=lambda x: -x[1]):
        print(f"  {status}: {cnt}")

    if dry_run:
        print("\n[dry-run] 未执行任何删除。加 --execute 实际执行。")
        conn.close()
        return

    # 删除关联 events 和缩略图
    deleted_events = 0
    deleted_thumbs = 0
    for v in to_delete:
        events = conn.execute(
            "SELECT id, thumbnail_path FROM events WHERE video_id = ?", (v["id"],)
        ).fetchall()
        for e in events:
            if e["thumbnail_path"]:
                thumb_path = PROJECT_ROOT / e["thumbnail_path"]
                if thumb_path.exists():
                    thumb_path.unlink()
                    deleted_thumbs += 1
        conn.execute("DELETE FROM events WHERE video_id = ?", (v["id"],))
        deleted_events += len(events)

    # 删除 video 记录
    video_ids = [v["id"] for v in to_delete]
    if video_ids:
        placeholders = ",".join("?" * len(video_ids))
        conn.execute(f"DELETE FROM videos WHERE id IN ({placeholders})", video_ids)

    conn.commit()

    # 清理孤儿缩略图（events 已删但文件还在的）
    event_thumbs = set(
        r[0] for r in conn.execute("SELECT thumbnail_path FROM events WHERE thumbnail_path IS NOT NULL")
    )
    orphan_thumbs = 0
    if THUMBNAILS_DIR.exists():
        for f in THUMBNAILS_DIR.glob("*.jpg"):
            rel = str(f.relative_to(PROJECT_ROOT))
            if rel not in event_thumbs:
                f.unlink()
                orphan_thumbs += 1

    conn.close()

    print(f"\n已删除 videos 记录: {len(to_delete)}")
    print(f"已删除 events 记录: {deleted_events}")
    print(f"已清理缩略图文件: {deleted_thumbs + orphan_thumbs}")


if __name__ == "__main__":
    import sys
    dry_run = "--execute" not in sys.argv
    cleanup_orphans(dry_run=dry_run)