from __future__ import annotations

from copy import deepcopy
from typing import Any

from fastapi import HTTPException
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from app.enums.private_portrait import (
    PRIVATE_PORTRAIT_ASSET_URI_PREFIX,
    PrivatePortraitAssetStatus,
    PrivatePortraitAssetType,
    PrivatePortraitEventSource,
    PrivatePortraitEventStatus,
    PrivatePortraitEventType,
    PrivatePortraitReferenceSource,
)
from app.models.private_portrait import PrivatePortraitAsset
from app.services.operation_log_service import log_operation_error, log_operation_event

DOMAIN = "private_portrait"


_ASSET_TYPE_TO_REFERENCE_TYPE = {
    PrivatePortraitAssetType.IMAGE.value: "image",
    PrivatePortraitAssetType.VIDEO.value: "video",
    PrivatePortraitAssetType.AUDIO.value: "audio",
}


_SUPPORTED_GEN_TYPES = {"image", "video"}


def _ref_get(ref: Any, key: str) -> Any:
    if isinstance(ref, dict):
        return ref.get(key)
    return getattr(ref, key, None)


def _ref_set(ref: Any, key: str, value: Any) -> None:
    if isinstance(ref, dict):
        ref[key] = value
    else:
        setattr(ref, key, value)


def _normalize_gen_type(gen_type: str | None) -> str | None:
    value = (gen_type or "").strip().lower()
    if not value:
        return None
    if value not in _SUPPORTED_GEN_TYPES:
        raise HTTPException(status_code=400, detail="gen_type 仅支持 image 或 video")
    return value


def _normalize_ref_type(value: Any) -> str:
    return str(value or "").strip().lower()


async def resolve_private_portrait_references(
    db: AsyncSession,
    *,
    user_id: str,
    media_references: list[Any] | None,
    gen_type: str | None = None,
) -> list[Any] | None:
    """Resolve private portrait references before dispatching a generation task.

    generation_ai_service.py 和 generation_task_factory_service.py 都会传 gen_type。
    这里保留该参数用于兼容调用方，并做基础校验，避免接口因函数签名不一致直接 500。
    """
    normalized_gen_type = _normalize_gen_type(gen_type)
    if not media_references:
        return media_references

    refs = deepcopy(media_references)
    ids = [
        str(_ref_get(ref, "private_asset_id"))
        for ref in refs
        if _ref_get(ref, "source") == PrivatePortraitReferenceSource.PRIVATE_PORTRAIT_ASSET.value
        and _ref_get(ref, "private_asset_id")
    ]
    ids = list(dict.fromkeys(ids))
    if not ids:
        return refs

    log_operation_event(
        domain=DOMAIN,
        event_type=PrivatePortraitEventType.REFERENCE_RESOLVE_START.value,
        event_status=PrivatePortraitEventStatus.PENDING.value,
        source=PrivatePortraitEventSource.SERVICE.value,
        user_id=user_id,
        detail={"private_asset_ids": ids, "gen_type": normalized_gen_type},
    )

    try:
        rows = await db.execute(select(PrivatePortraitAsset).where(PrivatePortraitAsset.id.in_(ids)))
        asset_map = {asset.id: asset for asset in rows.scalars().all()}

        for ref in refs:
            if _ref_get(ref, "source") != PrivatePortraitReferenceSource.PRIVATE_PORTRAIT_ASSET.value:
                continue

            asset_id = str(_ref_get(ref, "private_asset_id") or "")
            if not asset_id:
                raise HTTPException(status_code=400, detail="真人素材引用缺少 private_asset_id")

            asset = asset_map.get(asset_id)
            if not asset:
                raise HTTPException(status_code=400, detail="真人素材不存在")
            if asset.user_id != user_id:
                raise HTTPException(status_code=403, detail="真人素材不属于当前用户")
            if asset.deleted_at is not None:
                raise HTTPException(status_code=400, detail="真人素材已删除")
            if asset.status != PrivatePortraitAssetStatus.ACTIVE.value:
                raise HTTPException(status_code=400, detail=f"真人素材状态为 {asset.status}，Active 后才可用于生成")
            if not asset.remote_asset_id:
                raise HTTPException(status_code=400, detail="真人素材缺少远程 AssetId")

            expected_ref_type = _ASSET_TYPE_TO_REFERENCE_TYPE.get(asset.asset_type)
            ref_type = _normalize_ref_type(_ref_get(ref, "type"))
            if expected_ref_type and ref_type and ref_type != expected_ref_type:
                raise HTTPException(status_code=400, detail=f"真人素材类型不匹配：引用为 {ref_type}，素材为 {expected_ref_type}")

            _ref_set(ref, "source", PrivatePortraitReferenceSource.PRIVATE_PORTRAIT_ASSET.value)
            _ref_set(ref, "private_asset_id", asset.id)
            _ref_set(ref, "remote_asset_id", asset.remote_asset_id)
            _ref_set(ref, "url", f"{PRIVATE_PORTRAIT_ASSET_URI_PREFIX}{asset.remote_asset_id}")
            if expected_ref_type:
                _ref_set(ref, "type", expected_ref_type)
            if not _ref_get(ref, "name") and asset.name:
                _ref_set(ref, "name", asset.name)

        log_operation_event(
            domain=DOMAIN,
            event_type=PrivatePortraitEventType.REFERENCE_RESOLVE_SUCCESS.value,
            event_status=PrivatePortraitEventStatus.SUCCESS.value,
            source=PrivatePortraitEventSource.SERVICE.value,
            user_id=user_id,
            detail={"count": len(ids), "gen_type": normalized_gen_type},
        )
        return refs
    except Exception as exc:
        log_operation_error(
            domain=DOMAIN,
            event_type=PrivatePortraitEventType.REFERENCE_RESOLVE_FAILED.value,
            source=PrivatePortraitEventSource.SERVICE.value,
            user_id=user_id,
            detail={"private_asset_ids": ids, "gen_type": normalized_gen_type},
            exc=exc,
        )
        raise