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

由 start_fresh.sh 在 uvicorn 之前调用，使 FishMeasure 与 FishAction 均在无缓存下重新推理。
可通过环境变量 KEEP_MEASURE_OUTPUT=1 保留测量输出目录以复用点云。
"""

from __future__ import annotations

import os
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,
    )

    # 检查是否保留测量输出目录（用于复用点云）
    keep_measure_output = os.environ.get("KEEP_MEASURE_OUTPUT", "").strip() in ("1", "true", "yes")

    if keep_measure_output:
        # 只清理其他目录，保留 measure_output_root
        from app.db import _safe_rm_tree
        _safe_rm_tree(s.action_output_root)
        _safe_rm_tree(s.media_root)
        _safe_rm_tree(s.stream_tmp_dir)
        print(
            "[prestart-fresh] cleared compute dirs (kept measure_output for cloud reuse): "
            f"action_output={s.action_output_root}, "
            f"media={s.media_root}, stream_tmp={s.stream_tmp_dir}",
            flush=True,
        )
    else:
        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()