from __future__ import annotations

import json
import os
import sys
import tempfile
from datetime import datetime, timezone
from pathlib import Path

from app.logging_config import format_json_pretty
from app.settings import Settings
from app.state import HealthSnapshot
from app.subprocess_run import run_subprocess_with_log
from loguru import logger

BEHAVIOR_EN_TO_ZH = {
    "feeding": "吃饵",
    "normal": "正常游行",
    "scared": "惊吓",
}


def _py_exe(settings: Settings) -> str:
    return settings.python_fish_action or sys.executable


def behavior_to_health(behavior_en: str) -> str:
    if behavior_en == "scared":
        return "不健康"
    return "健康"


def run_action_subprocess(mp4_path: Path, settings: Settings) -> str:
    script = settings.fish_action_root / "predict_video_x3d_3class.py"
    if not script.is_file():
        raise FileNotFoundError(f"Missing FishAction script: {script}")

    mp4_path = mp4_path.resolve()
    path_prefix = str(mp4_path.parent)
    rel_name = mp4_path.name

    with tempfile.NamedTemporaryFile(
        mode="w", suffix=".csv", delete=False, encoding="utf-8"
    ) as tmp:
        tmp.write(f"{rel_name} 0\n")
        csv_path = tmp.name

    out_fd, out_json = tempfile.mkstemp(suffix="_pred.json")
    os.close(out_fd)

    try:
        cmd = [
            _py_exe(settings),
            str(script),
            "--checkpoint",
            settings.action_checkpoint,
            "--csv",
            csv_path,
            "--path_prefix",
            path_prefix,
            "--clips_per_video",
            str(settings.action_clips_per_video),
            "--batch_size",
            str(settings.action_batch_size),
            "--num_workers",
            str(settings.action_num_workers),
            "--output_json",
            out_json,
            "--log_interval",
            "0",
        ]
        proc = run_subprocess_with_log(
            cmd,
            cwd=str(settings.fish_action_root),
            env=os.environ.copy(),
            log_name="FishAction",
            stream_to_logger=False,
        )
        if proc.returncode != 0:
            err = proc.stdout or ""
            raise RuntimeError(
                f"predict_video_x3d_3class.py failed ({proc.returncode}): {err[-4000:]}"
            )
        if not Path(out_json).is_file():
            raise RuntimeError(f"No output_json written: {out_json}")
        with open(out_json, encoding="utf-8") as f:
            rows = json.load(f)
        if not rows:
            raise RuntimeError("Empty prediction JSON")
        pred_en = str(rows[0].get("pred_3class", "")).strip().lower()
        logger.debug(
            "[FishAction] prediction row:\n{}",
            format_json_pretty(rows[0]),
        )
        if pred_en not in BEHAVIOR_EN_TO_ZH:
            raise RuntimeError(f"Unexpected pred_3class: {pred_en!r}")
        return pred_en
    finally:
        Path(csv_path).unlink(missing_ok=True)
        Path(out_json).unlink(missing_ok=True)


def run_full_action(mp4_path: Path, settings: Settings) -> HealthSnapshot:
    logger.info("[FishAction] start mp4={}", mp4_path.resolve())
    pred_en = run_action_subprocess(mp4_path, settings)
    zh = BEHAVIOR_EN_TO_ZH[pred_en]
    health = behavior_to_health(pred_en)
    logger.info(
        "[FishAction] done mp4={} pred_3class={} behavior_zh={} health={}",
        mp4_path.name,
        pred_en,
        zh,
        health,
    )
    return HealthSnapshot(
        behavior_result=zh,
        health_result=health,
        updated_at=datetime.now(timezone.utc),
        raw_class_en=pred_en,
    )