"""启动前清空状态：SQLite、watch 旧 JSON、测量/行为运行时目录。

由 start.sh / start_fresh.sh 在 uvicorn 之前调用，使 FishMeasure 与 FishAction 均在无缓存下重新推理。
"""

from __future__ import annotations

from pathlib import Path

from app.db import clear_runtime_compute_dirs, remove_sqlite_database_files
from app.settings import get_settings


def _rm_legacy_json(path: Path | None) -> None:
    if path is None:
        return
    try:
        if path.is_file():
            path.unlink()
            print(f"[prestart-fresh] removed legacy JSON {path}", flush=True)
    except OSError as e:
        print(f"[prestart-fresh] skip {path}: {e}", flush=True)


def run_prestart_fresh() -> None:
    s = get_settings()

    remove_sqlite_database_files(s)
    print(
        f"[prestart-fresh] removed SQLite at {s.sqlite_path} (and -wal/-shm if present).",
        flush=True,
    )

    clear_runtime_compute_dirs(s)
    print(
        "[prestart-fresh] cleared compute dirs: "
        f"measure_output={s.measure_output_root}, "
        f"action_output={s.action_output_root}, "
        f"media={s.media_root}, stream_tmp={s.stream_tmp_dir}",
        flush=True,
    )

    if s.measure_watch_use_state_file:
        if s.measure_watch_state_file is not None:
            _rm_legacy_json(s.measure_watch_state_file)
        elif s.measure_watch_dir is not None:
            _rm_legacy_json(
                s.measure_watch_dir / ".fishmeasure_watch_processed.json"
            )

    if s.action_watch_use_state_file:
        if s.action_watch_state_file is not None:
            _rm_legacy_json(s.action_watch_state_file)
        elif s.action_watch_dir is not None:
            _rm_legacy_json(
                s.action_watch_dir / ".fishaction_watch_processed.json"
            )

    print("[prestart-fresh] done.", flush=True)


def main() -> None:
    run_prestart_fresh()


if __name__ == "__main__":
    main()