"""Kling AI video generation — PiAPI gateway 경유.

POST https://api.piapi.ai/api/v1/task → GET /api/v1/task/{id} 폴링 → data.output.video_url 다운로드.
"""
from __future__ import annotations

import logging
import os
import time
from typing import Optional

import requests

from nas_client import webhook_update_task

logger = logging.getLogger(__name__)

PIAPI_BASE_URL = "https://api.piapi.ai/api/v1"
VIDEO_MEDIA_ROOT = os.getenv("VIDEO_MEDIA_ROOT", "/mnt/nas/webpage/data/video")
VIDEO_MEDIA_URL_PREFIX = os.getenv("VIDEO_MEDIA_URL_PREFIX", "/media/video")

POLL_INTERVAL = 10   # Kling은 30~180초
POLL_MAX_ATTEMPTS = 60   # 최대 10분

DEFAULT_VERSION = "2.6"


def _headers() -> dict:
    api_key = os.getenv("PIAPI_API_KEY", "")
    return {
        "x-api-key": api_key,
        "Content-Type": "application/json",
    }


def run_kling_generation(task_id: str, params: dict) -> None:
    """Kling으로 영상 생성 → mp4 → NAS SMB → webhook."""
    try:
        if not os.getenv("PIAPI_API_KEY"):
            webhook_update_task(task_id, "failed", 0, "", error="PIAPI_API_KEY 미설정")
            return

        webhook_update_task(task_id, "processing", 5, "Kling API 호출 중...")

        input_obj = {
            "prompt": params["prompt"][:2500],
            "duration": params.get("duration", 5),
            "aspect_ratio": params.get("aspect_ratio", "16:9"),
            "mode": params.get("mode", "std"),
            "version": params.get("model") or DEFAULT_VERSION,
        }
        if params.get("negative_prompt"):
            input_obj["negative_prompt"] = params["negative_prompt"][:2500]
        if params.get("cfg_scale") is not None:
            input_obj["cfg_scale"] = str(params["cfg_scale"])
        if params.get("image_url"):
            input_obj["image_url"] = params["image_url"]

        body = {
            "model": "kling",
            "task_type": "video_generation",
            "input": input_obj,
            "config": {"service_mode": "public"},
        }

        resp = requests.post(f"{PIAPI_BASE_URL}/task", headers=_headers(), json=body, timeout=30)
        if resp.status_code != 200:
            webhook_update_task(task_id, "failed", 0, "",
                                error=f"Kling/PiAPI 오류: {resp.status_code} {resp.text[:300]}")
            return

        body_json = resp.json()
        if body_json.get("code") != 200:
            webhook_update_task(task_id, "failed", 0, "",
                                error=f"Kling/PiAPI 거부: {body_json.get('message', '?')}")
            return

        piapi_task_id = (body_json.get("data") or {}).get("task_id", "")
        if not piapi_task_id:
            webhook_update_task(task_id, "failed", 0, "", error="Kling/PiAPI 응답에 task_id 없음")
            return

        webhook_update_task(task_id, "processing", 15, "Kling 작업 등록됨")

        # 폴링 — GET /task/{id}
        video_url = None
        for attempt in range(POLL_MAX_ATTEMPTS):
            time.sleep(POLL_INTERVAL)
            fetch = requests.get(f"{PIAPI_BASE_URL}/task/{piapi_task_id}",
                                 headers=_headers(), timeout=30)
            if fetch.status_code != 200:
                continue
            fd = fetch.json()
            data = fd.get("data", {})
            status = data.get("status", "")
            scaled = min(15 + int((attempt / POLL_MAX_ATTEMPTS) * 65), 79)
            webhook_update_task(task_id, "processing", scaled, f"Kling 생성 중... ({status})")

            if status == "Completed":
                video_url = (data.get("output") or {}).get("video_url", "")
                break
            elif status in ("Failed", "failed"):
                err = (data.get("error") or {}).get("message", "Kling 작업 실패")
                webhook_update_task(task_id, "failed", 0, "", error=err)
                return
            # Pending/Processing/Staged → 계속 폴링
        else:
            webhook_update_task(task_id, "failed", 0, "", error="Kling 폴링 timeout (10분)")
            return

        if not video_url:
            webhook_update_task(task_id, "failed", 0, "", error="Kling 완료했으나 video_url 없음")
            return

        webhook_update_task(task_id, "processing", 85, "Kling 결과 다운로드 중...")
        filename = f"{task_id}.mp4"
        os.makedirs(VIDEO_MEDIA_ROOT, exist_ok=True)
        file_path = os.path.join(VIDEO_MEDIA_ROOT, filename)

        dl = requests.get(video_url, stream=True, timeout=300)
        dl.raise_for_status()
        with open(file_path, "wb") as f:
            for chunk in dl.iter_content(chunk_size=8192):
                f.write(chunk)

        local_url = f"{VIDEO_MEDIA_URL_PREFIX}/{filename}"
        webhook_update_task(task_id, "succeeded", 100, "Kling 생성 완료", video_url=local_url)

    except requests.Timeout:
        webhook_update_task(task_id, "failed", 0, "", error="Kling/PiAPI 타임아웃")
    except Exception as e:
        logger.exception("Kling generation error task=%s", task_id)
        webhook_update_task(task_id, "failed", 0, "", error=str(e))