import asyncio
import json
import logging
import os
import time
from datetime import datetime, timezone
from sqlalchemy.ext.asyncio import AsyncSession

from app.models.api.api_key import ApiKey
from app.schemas.api_v3.image import ApiImageGenerateRequest, ApiImageGenerateResponse, ApiImageGenerateDataItem
from app.schemas.api_v3.video import ApiVideoCreateRequest, ApiVideoCreateResponse
from app.services.api_v3 import task_service, engine_service, upscale_service
from app.services.api_v3.quota_service import can_start_video_task
from app.services.api_v3.pricing_service import calc_api_video_price, calc_api_image_price, PricingNotConfiguredError
from app.services.api_v3.logging_service import log_model_request

logger = logging.getLogger("videogen")


def _make_image_url(local_path: str) -> str:
    """将本地图片路径转为完整可访问 URL。"""
    if not local_path:
        return local_path
    # 如果已经是完整 URL，直接返回
    if local_path.startswith(("http://", "https://")):
        return local_path
    from app.config import settings
    from app.services.resource_signed_url_service import build_resource_signed_url
    # 生成签名 URL
    signed = build_resource_signed_url(local_path)
    if signed and not signed.startswith(("http://", "https://")):
        base = settings.BASE_URL.rstrip("/")
        if signed.startswith("/"):
            signed = f"{base}{signed}"
        else:
            signed = f"{base}/{signed}"
    return signed or local_path


async def submit_video_generation(
    db: AsyncSession,
    key: ApiKey,
    callable_models: list[dict],
    req: ApiVideoCreateRequest,
) -> ApiVideoCreateResponse:
    """提交视频生成任务（异步）。

    流程：
    1. 检查并发视频任务数
    2. 解析引擎
    3. 构建超分快照
    4. 创建任务记录
    5. 入队 Celery 任务
    6. 返回 task_id
    """
    # 1. 检查是否可以立即启动（并发限制）
    can_start = await can_start_video_task(key, db)

    # 2. 解析引擎
    engine_id, engine = await engine_service.resolve_engine_by_model_name(
        db, req.model, callable_models, "video"
    )
    engine_snapshot = engine_service.build_engine_snapshot(engine)

    # 3. 构建超分快照
    provider_resolution, upscale_enabled, upscale_snapshot_json = await upscale_service.build_api_upscale_snapshot(
        db, key.id, req.resolution or "480p", req.ratio
    )

    # 如果超分要求不同的生成分辨率，使用超分的
    final_provider_resolution = provider_resolution or req.resolution or "480p"

    def _get_max_supported_duration(engine) -> int | None:
        """从引擎 supported_durations 获取最大时长。"""
        try:
            durations = json.loads(engine.supported_durations) if engine.supported_durations else []
            return max(durations) if durations else engine.max_duration
        except (json.JSONDecodeError, TypeError, ValueError):
            return engine.max_duration

    # 3.5 验证传入的媒体文件是否符合引擎配置要求
    from app.services.api_v3.file_service import process_media_url
    from app.services.video_upscale.media_service import probe_video
    from fastapi import HTTPException, status  # noqa: F401
    
    input_image_count = 0
    input_video_count = 0
    input_audio_count = 0
    input_video_duration = 0.0
    local_media_refs = []  # 存储本地路径

    # 统计各类媒体数量
    for p in req.content:
        ptype = p.type
        if ptype == "image_url":
            input_image_count += 1
        elif ptype == "video_url":
            input_video_count += 1
        elif ptype == "audio_url":
            input_audio_count += 1

    # 视频引擎校验（本函数仅处理视频生成）
    # 校验图片数量限制
    if input_image_count > (engine.max_image_count or 0):
        raise HTTPException(
            status_code=400,
            detail=f"该引擎最多支持 {engine.max_image_count} 张参考图片，当前传入 {input_image_count} 张",
        )
    # 校验视频数量限制
    if input_video_count > (engine.max_video_count or 0):
        raise HTTPException(
            status_code=400,
            detail=f"该引擎最多支持 {engine.max_video_count} 个参考视频，当前传入 {input_video_count} 个",
        )
    # 校验音频数量限制
    if input_audio_count > (engine.max_audio_count or 0):
        raise HTTPException(
            status_code=400,
            detail=f"该引擎最多支持 {engine.max_audio_count} 个参考音频，当前传入 {input_audio_count} 个",
        )

    for p in req.content:
        ptype = p.type
        if ptype == "text":
            local_media_refs.append(p.model_dump(exclude_none=True))
            continue

        original_url = ""
        if ptype == "image_url" and p.image_url:
            original_url = p.image_url.get("url", "")
        elif ptype == "video_url" and p.video_url:
            original_url = p.video_url.get("url", "")
        elif ptype == "audio_url" and p.audio_url:
            original_url = p.audio_url.get("url", "")

        # 下载文件到本地
        try:
            local_path = await process_media_url(original_url, ptype.replace("_url", ""))
        except Exception as exc:
            logger.warning("Failed to download media %s: %s", original_url[:80], exc)
            local_path = original_url

        # 如果是视频/音频，探测实际时长并校验
        if ptype in ("video_url", "audio_url") and local_path:
            try:
                media_info = await probe_video(local_path)
                if media_info and media_info.duration_seconds:
                    duration = media_info.duration_seconds
                    # 校验最低时长（2秒）
                    if duration < 2.0:
                        raise HTTPException(
                            status_code=400,
                            detail=f"上传的{ptype.replace('_url', '')}时长不能低于2秒，当前时长: {duration:.1f}秒",
                        )
                    # 校验最高时长（根据引擎 supported_durations 最大值）
                    max_duration = _get_max_supported_duration(engine)
                    if max_duration and duration > max_duration:
                        raise HTTPException(
                            status_code=400,
                            detail=f"上传的{ptype.replace('_url', '')}时长不能超过{max_duration}秒，当前时长: {duration:.1f}秒",
                        )
                    if ptype == "video_url":
                        input_video_duration += duration
            except HTTPException:
                raise
            except Exception as exc:
                logger.warning("Failed to probe media duration: %s", exc)

        local_media_refs.append({
            "type": ptype,
            ptype: {"url": local_path},
            "role": p.role,
        })

    # 3.6 计算价格（基于实际探测的视频时长）
    try:
        estimated_price = await calc_api_video_price(
            db,
            duration=req.duration or 5,
            resolution=req.resolution or "480p",
            engine_id=engine_id,
            input_video_duration=input_video_duration,
            input_image_count=input_image_count,
        )
    except PricingNotConfiguredError as exc:
        from fastapi import HTTPException, status
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=str(exc),
        )
    # 预检配额
    if key.quota_limit is not None and key.quota_used + estimated_price > key.quota_limit:
        from fastapi import HTTPException, status
        raise HTTPException(
            status_code=status.HTTP_429_TOO_MANY_REQUESTS,
            detail=f"配额不足 (需要 {estimated_price:.2f} 元, 剩余 {key.quota_limit - key.quota_used:.2f} 元)",
        )
    # 预扣配额
    if estimated_price > 0:
        key.quota_used = round((key.quota_used or 0.0) + estimated_price, 2)

    # 4. 创建任务记录（幂等性已在路由层检查）
    content_dicts = [p.model_dump(exclude_none=True) for p in req.content]
    task = await task_service.create_video_task(
        db=db,
        api_key_id=key.id,
        model_name=req.model,
        engine_id=engine_id,
        engine_snapshot=engine_snapshot,
        content=content_dicts,
        ratio=req.ratio,
        duration=req.duration,
        resolution=req.resolution,
        provider_generation_resolution=final_provider_resolution,
        upscale_enabled=upscale_enabled,
        upscale_snapshot_json=upscale_snapshot_json,
        idempotency_key=req.idempotency_key,
        local_media_refs=local_media_refs,
    )
    task.credits_cost = estimated_price  # 记录预扣金额

    # 根据并发限制决定立即执行还是排队
    if can_start:
        # 立即执行
        task.status = "pending"
        task.pipeline_stage = "queued"
    else:
        # 排队等待
        task.status = "queued"
        task.pipeline_stage = "waiting_concurrency"

    await db.commit()

    # 提交时即记录使用日志（配额已预扣）
    try:
        from app.services.api_v3.usage_log_service import record_usage
        quota_before = key.quota_used - estimated_price  # 扣减前的余额
        quota_after = key.quota_used  # 扣减后的余额
        price_detail = {
            "base_price": getattr(locals(), "base_price", 0),
            "per_second_price": getattr(locals(), "per_second_price", 0),
            "duration": req.duration,
            "resolution": req.resolution,
            "ratio": req.ratio,
            "total": estimated_price,
        }
        await record_usage(
            db=db,
            api_key_id=key.id,
            request_type="video_create",
            model_name=req.model,
            gen_type="video",
            status="success",
            task_id=task.id,
            credits_cost=estimated_price,
            price_action="deduct",
            resolution=req.resolution,
            duration=req.duration,
            quota_before=quota_before,
            quota_after=quota_after,
            price_detail_json=json.dumps(price_detail, ensure_ascii=False),
        )
    except Exception as log_exc:
        logger.error("Failed to record usage on submit: %s", log_exc)

    # 记录模型调用日志
    log_model_request(
        engine_id=engine_id,
        model_name=req.model,
        task_id=task.id,
        params={
            "ratio": req.ratio,
            "duration": req.duration,
            "resolution": req.resolution,
            "generate_audio": req.generate_audio,
            "watermark": req.watermark,
            "content_count": len(req.content),
            "queued": not can_start,
        },
    )

    # 5. 只有立即执行的才入队 Celery
    if can_start:
        from app.tasks.api_generation_tasks import api_create_generation_task
        api_create_generation_task.apply_async(
            args=[task.id],
            queue="gen_api_create",
        )

    status_str = "queued" if can_start else "pending_queue"
    logger.info("API video task created: task_id=%s model=%s key=%s price=%.2f status=%s", task.id, req.model, key.id, estimated_price, status_str)

    return ApiVideoCreateResponse(id=task.id)


async def generate_image_sync(
    db: AsyncSession,
    key: ApiKey,
    callable_models: list[dict],
    req: "ApiImageGenerateRequest",
    start_time: float,
) -> ApiImageGenerateResponse:
    """同步生成图片。

    流程：
    1. 解析引擎
    2. 创建任务记录
    3. 调用 Volcano Ark SDK（同步）
    4. 下载图片
    5. 更新任务状态
    6. 记录使用日志
    7. 返回结果
    """
    from app.services.api_v3.usage_log_service import record_usage

    # 1. 解析引擎
    engine_id, engine = await engine_service.resolve_engine_by_model_name(
        db, req.model, callable_models, "image"
    )
    engine_snapshot = engine_service.build_engine_snapshot(engine)

    # 2. 创建任务记录
    task = await task_service.create_image_task(
        db=db,
        api_key_id=key.id,
        model_name=req.model,
        engine_id=engine_id,
        engine_snapshot=engine_snapshot,
        prompt=req.prompt,
        size=req.size,
    )

    # 2.5 验证传入的媒体文件是否符合引擎配置要求
    # 校验参考图片数量限制
    input_image_count = len(req.image) if req.image else 0
    if input_image_count > (engine.max_reference_image_count or 0):
        raise HTTPException(
            status_code=400,
            detail=f"该引擎最多支持 {engine.max_reference_image_count} 张参考图片，当前传入 {input_image_count} 张",
        )
    # 校验组图数量限制
    generation_count = req.generation_count or 1
    if generation_count > (engine.multi_image_max_images or 1):
        raise HTTPException(
            status_code=400,
            detail=f"该引擎最多支持生成 {engine.multi_image_max_images} 张图片，当前请求 {generation_count} 张",
        )
    try:
        estimated_price = await calc_api_image_price(
            db,
            image_size=req.size or "2K",
            engine_id=engine_id,
            input_image_count=input_image_count,
        )
    except PricingNotConfiguredError as exc:
        from fastapi import HTTPException, status
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=str(exc),
        )
    # 预检配额
    if key.quota_limit is not None and key.quota_used + estimated_price > key.quota_limit:
        from fastapi import HTTPException, status
        raise HTTPException(
            status_code=status.HTTP_429_TOO_MANY_REQUESTS,
            detail=f"配额不足 (需要 {estimated_price:.2f} 元, 剩余 {key.quota_limit - key.quota_used:.2f} 元)",
        )
    # 预扣配额
    if estimated_price > 0:
        key.quota_used = round((key.quota_used or 0.0) + estimated_price, 2)
    task.credits_cost = estimated_price
    await db.commit()

    # 提交时即记录使用日志（配额已预扣）
    try:
        quota_before = key.quota_used - estimated_price
        quota_after = key.quota_used
        price_detail = {
            "base_price": getattr(locals(), "base_price", 0),
            "size": req.size,
            "generation_count": req.generation_count or 1,
            "total": estimated_price,
        }
        await record_usage(
            db=db,
            api_key_id=key.id,
            request_type="image_generate",
            model_name=req.model,
            gen_type="image",
            status="success",
            task_id=task.id,
            credits_cost=estimated_price,
            price_action="deduct",
            resolution=req.size,
            quota_before=quota_before,
            quota_after=quota_after,
            price_detail_json=json.dumps(price_detail, ensure_ascii=False),
        )
    except Exception as log_exc:
        logger.error("Failed to record usage on image submit: %s", log_exc)

    try:
        # 设置总体超时（120秒，防止同步请求长时间挂起）
        _IMAGE_GEN_TIMEOUT = 120

        # 3. 调用 Volcano Ark SDK（同步函数，在线程中执行）
        from app.services.image_gen import submit_image_task, download_image
        from app.config import settings

        # 构建 media_references，下载图片到本地
        from app.services.api_v3.file_service import process_media_url

        image_refs = []
        if req.image:
            for url in req.image:
                try:
                    local_path = await process_media_url(url, "image")
                except Exception as exc:
                    logger.warning("Failed to download image %s: %s", url[:80], exc)
                    local_path = url
                image_refs.append({"type": "image", "url": local_path})

        # 临时设置 media_references
        task.media_references = json.dumps(image_refs, ensure_ascii=False) if image_refs else None
        task.image_size = req.size or "2K"
        await db.flush()

        # 在线程中执行同步 SDK 调用（带超时保护）
        result = await asyncio.wait_for(
            asyncio.to_thread(
                submit_image_task,
                db,
                engine,
                task,
                True,  # include_media_references
                req.generation_count or 1,
            ),
            timeout=_IMAGE_GEN_TIMEOUT,
        )

        # 4. 下载图片
        items = result.get("items", [])
        downloaded_items: list[ApiImageGenerateDataItem] = []

        for item in items:
            url = item.get("remote_result_url")
            if url:
                # 下载到本地
                date_dir = datetime.now().strftime("%Y%m%d")
                dest_dir = f"./storage/generate/api/images/{date_dir}"
                os.makedirs(dest_dir, exist_ok=True)
                dest_path = os.path.join(dest_dir, f"{task.id}_{item.get('generation_index', 1)}.png")
                try:
                    await asyncio.wait_for(
                        download_image(url, dest_path),
                        timeout=30,
                    )
                except asyncio.TimeoutError:
                    logger.warning("Image download timeout: %s", url[:80])
                except Exception as dl_err:
                    logger.warning("Image download failed: %s", dl_err)

                # 将本地路径转为完整 URL
                image_url = _make_image_url(dest_path)
                downloaded_items.append(ApiImageGenerateDataItem(
                    url=image_url,
                    size=item.get("size"),
                    output_format=item.get("output_format"),
                ))
            elif item.get("error_message"):
                downloaded_items.append(ApiImageGenerateDataItem(
                    url=None,
                ))

        # 5. 使用预扣金额（不再重复扣减）
        task.credits_cost = estimated_price

        # 6. 更新任务状态
        task.status = "completed"
        task.pipeline_stage = "done"
        task.generated_at = datetime.now(timezone.utc)
        if downloaded_items and downloaded_items[0].url:
            task.image_url = downloaded_items[0].url
        await db.commit()

        # 提交时已记录使用日志，成功时无需重复记录
        duration_ms = int((time.perf_counter() - start_time) * 1000)

        return ApiImageGenerateResponse(
            created=result.get("created", int(time.time())),
            data=downloaded_items,
            model=result.get("model", req.model),
        )

    except asyncio.TimeoutError:
        from fastapi import HTTPException, status
        logger.exception("API image generation timed out (task_id=%s)", task.id)
        # 超时：退回预扣配额
        if estimated_price > 0:
            key.quota_used = round(max(0, (key.quota_used or 0.0) - estimated_price), 2)
        task.status = "failed"
        task.error_message = "图片生成超时（超过120秒）"
        task.credits_cost = 0
        await db.commit()
        raise HTTPException(
            status_code=504,
            detail="图片生成超时，请稍后重试",
        )

    except Exception as exc:
        # 失败：退回预扣配额
        if estimated_price > 0:
            key.quota_used = round(max(0, (key.quota_used or 0.0) - estimated_price), 2)

        task.status = "failed"
        task.error_message = str(exc)
        task.credits_cost = 0  # 实际消耗为0（已退回）
        await db.commit()

        duration_ms = int((time.perf_counter() - start_time) * 1000)
        quota_after_refund = key.quota_used  # 退回后的余额
        await record_usage(
            db=db,
            api_key_id=key.id,
            request_type="image_generate",
            model_name=req.model,
            gen_type="image",
            status="failed",
            task_id=task.id,
            credits_cost=estimated_price,
            refund_amount=estimated_price,
            request_duration_ms=duration_ms,
            error_message=str(exc),
            error_code="generation_failed",
            price_action="refund",
            resolution=req.size,
            generation_count=req.generation_count or 1,
            quota_before=quota_after_refund,
            quota_after=quota_after_refund + estimated_price,
        )
        await db.commit()
        raise