"""
全局共享依赖：

- 认证：get_current_user / get_optional_user
- Port DI factory：get_sms_sender / get_llm_provider / get_tts_provider / ...
"""

from functools import lru_cache
from typing import Optional

from fastapi import Depends, HTTPException, status
from fastapi.security import OAuth2PasswordBearer
from sqlalchemy.ext.asyncio import AsyncSession

from app.core.config import settings
from app.core.db import get_async_db
from app.core.security import verify_token
from app.ports.asr import ASRProvider
from app.ports.embedding import EmbeddingProvider
from app.ports.image_gen import ImageGenerator
from app.ports.llm import LLMProvider
from app.ports.sms import SmsSender
from app.ports.storage import ObjectStorage
from app.ports.tts import TTSProvider

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="/api/auth/login")


# ── Port DI factories ───────────────────────────────────────


@lru_cache
def get_sms_sender() -> SmsSender:
    from app.adapters.sms.tencent import TencentSmsSender

    return TencentSmsSender(
        secret_id=settings.tencent_sms_secret_id,
        secret_key=settings.tencent_sms_secret_key,
        sdk_app_id=settings.tencent_sms_sdk_app_id,
        sign_name=settings.tencent_sms_sign_name,
        template_id=settings.tencent_sms_template_id,
        template_param_count=settings.tencent_sms_template_param_count,
    )


@lru_cache
def get_llm_provider() -> LLMProvider:
    from app.adapters.llm.deepseek import DeepSeekLLMProvider

    api_key = settings.deepseek_api_key or settings.llm_api_key
    base_url = settings.deepseek_base_url or settings.llm_base_url
    model = settings.deepseek_model or settings.llm_model or "deepseek-chat"
    return DeepSeekLLMProvider(
        api_key=api_key,
        base_url=base_url,
        model=model,
        temperature=settings.llm_temperature,
    )


@lru_cache
def get_llm_provider_fast() -> LLMProvider:
    """快档位：与默认共用密钥与 base_url，仅模型名可单独配置。"""
    fast = (settings.llm_fast_model or "").strip()
    if not fast:
        return get_llm_provider()
    from app.adapters.llm.deepseek import DeepSeekLLMProvider

    api_key = settings.deepseek_api_key or settings.llm_api_key
    base_url = settings.deepseek_base_url or settings.llm_base_url
    return DeepSeekLLMProvider(
        api_key=api_key,
        base_url=base_url,
        model=fast,
        temperature=settings.llm_temperature,
    )


@lru_cache
def get_tts_provider() -> TTSProvider:
    if settings.tts_provider == "tencent":
        from app.adapters.tts.tencent_tts import TencentTTSProvider

        return TencentTTSProvider(
            secret_id=settings.tencent_secret_id,
            secret_key=settings.tencent_secret_key,
            voice_type=settings.tts_voice_type,
            codec=settings.tts_codec,
        )
    from app.adapters.tts.openai_tts import OpenAITTSProvider

    return OpenAITTSProvider(api_key=settings.openai_api_key)


@lru_cache
def get_asr_provider() -> ASRProvider:
    if settings.asr_provider == "tencent":
        from app.adapters.asr.tencent_asr import TencentASRProvider

        return TencentASRProvider(
            secret_id=settings.tencent_secret_id,
            secret_key=settings.tencent_secret_key,
        )

    from app.adapters.asr.whisper_local import WhisperASRProvider

    return WhisperASRProvider(
        model_size=settings.asr_model_size,
        device=settings.asr_device,
        compute_type=settings.asr_compute_type,
        cache_dir=settings.asr_model_cache_dir,
    )


@lru_cache
def get_image_generator() -> ImageGenerator:
    from app.adapters.image_gen.liblib import LiblibImageGenerator

    return LiblibImageGenerator(
        access_key=settings.liblib_access_key,
        secret_key=settings.liblib_secret_key,
        base_url=settings.liblib_base_url,
        template_uuid=settings.liblib_template_uuid,
        poll_interval=settings.memoir_image_poll_interval,
        max_attempts=settings.memoir_image_max_attempts,
    )


@lru_cache
def get_object_storage() -> ObjectStorage:
    from app.adapters.storage.tencent_cos import TencentCosStorage

    return TencentCosStorage(
        secret_id=settings.tencent_cos_secret_id,
        secret_key=settings.tencent_cos_secret_key,
        region=settings.tencent_cos_region,
        bucket=settings.tencent_cos_bucket,
        base_url=settings.tencent_cos_base_url,
        token=settings.tencent_cos_token,
    )


@lru_cache
def get_embedding_provider() -> EmbeddingProvider:
    from app.adapters.embedding.zhipu import ZhipuEmbeddingProvider

    return ZhipuEmbeddingProvider(
        api_key=settings.zhipu_api_key,
        base_url=settings.embedding_base_url or None,
        model=settings.embedding_model,
    )


# ── Auth dependencies ────────────────────────────────────────


async def get_current_user(
    token: str = Depends(oauth2_scheme),
    db: AsyncSession = Depends(get_async_db),
):
    """Resolve authenticated user from JWT access token."""
    from app.features.user.models import User  # deferred to avoid circular import

    credentials_exception = HTTPException(
        status_code=status.HTTP_401_UNAUTHORIZED,
        detail="无法验证凭据",
        headers={"WWW-Authenticate": "Bearer"},
    )

    payload = verify_token(token)
    if payload is None:
        raise credentials_exception

    user_id: str | None = payload.get("sub")
    if user_id is None:
        raise credentials_exception

    if payload.get("type") != "access":
        raise credentials_exception

    user = await db.get(User, user_id)
    if user is None:
        raise credentials_exception

    return user


async def get_optional_user(
    token: Optional[str] = Depends(oauth2_scheme),
    db: AsyncSession = Depends(get_async_db),
):
    """Return user if a valid token is provided, else None."""
    if token is None:
        return None
    try:
        return await get_current_user(token, db)
    except HTTPException:
        return None