from fastapi import APIRouter, Depends, HTTPException

from core_domain import ChatCompletionRequestContract, ChatCompletionResponseContract, ServiceHealth
from app.application.services import ModelGatewayApplicationService
from app.bootstrap.settings import ModelGatewayServiceSettings
from app.infrastructure.provider import ModelProviderClient, ModelProviderClientError

router = APIRouter()


def get_model_gateway_settings() -> ModelGatewayServiceSettings:
    return ModelGatewayServiceSettings()


def get_model_gateway_application_service(
    settings: ModelGatewayServiceSettings = Depends(get_model_gateway_settings),
) -> ModelGatewayApplicationService:
    return ModelGatewayApplicationService(
        provider_client=ModelProviderClient(settings=settings),
        settings=settings,
    )


@router.get("/health", response_model=ServiceHealth)
def health_check(
    settings: ModelGatewayServiceSettings = Depends(get_model_gateway_settings),
) -> ServiceHealth:
    provider_status = "configured" if settings.provider_base_url else "missing"
    return ServiceHealth(service="model-gateway-service", status="ok", database=provider_status)


@router.post("/chat-completions", response_model=ChatCompletionResponseContract)
def create_chat_completion(
    payload: ChatCompletionRequestContract,
    service: ModelGatewayApplicationService = Depends(get_model_gateway_application_service),
) -> ChatCompletionResponseContract:
    try:
        return service.create_chat_completion(payload)
    except ModelProviderClientError as exc:
        raise HTTPException(status_code=502, detail=str(exc)) from exc