import json

from fastapi import APIRouter, Depends
from fastapi import Response

from app.api.dependencies import get_backend_service
from app.core.secret_codec import list_secret_fields
from app.models.entities import Backend
from app.schemas.backend import (
    BackendCheckResponse,
    BackendListResponse,
    BackendMutationResponse,
    BackendSummary,
    CreateBackendRequest,
    CreateBackendResponse,
    UpdateBackendRequest,
)
from app.services.backend_service import BackendService

router = APIRouter()


def summarize_backend(backend: Backend) -> BackendSummary:
    summary = BackendSummary.model_validate(backend, from_attributes=True)
    public_config = json.loads(backend.public_config_json)
    summary.config = public_config
    summary.secret_fields = list_secret_fields(backend.secret_config_json)
    return summary


@router.get("", response_model=BackendListResponse)
async def list_backends(
    service: BackendService = Depends(get_backend_service),
) -> BackendListResponse:
    items = await service.list_backends()
    return BackendListResponse(
        items=[summarize_backend(item) for item in items]
    )


@router.post("", response_model=CreateBackendResponse)
async def create_backend(
    payload: CreateBackendRequest,
    service: BackendService = Depends(get_backend_service),
) -> CreateBackendResponse:
    backend = await service.create_backend(
        name=payload.name,
        backend_type=payload.type,
        stability_class=payload.stability_class,
        read_priority=payload.read_priority,
        write_priority=payload.write_priority,
        config=payload.config,
    )
    return CreateBackendResponse(backend=summarize_backend(backend))


@router.post("/{backend_id}/check", response_model=BackendCheckResponse)
async def check_backend(
    backend_id: str,
    service: BackendService = Depends(get_backend_service),
) -> BackendCheckResponse:
    backend, status, detail = await service.check_backend(backend_id)
    return BackendCheckResponse(
        backend_id=backend.id,
        status=status,
        checked_at=backend.last_health_checked_at,
        detail=detail,
    )


@router.patch("/{backend_id}", response_model=BackendMutationResponse)
async def update_backend(
    backend_id: str,
    payload: UpdateBackendRequest,
    service: BackendService = Depends(get_backend_service),
) -> BackendMutationResponse:
    backend = await service.update_backend(
        backend_id,
        name=payload.name,
        stability_class=payload.stability_class,
        read_priority=payload.read_priority,
        write_priority=payload.write_priority,
        config=payload.config,
    )
    return BackendMutationResponse(backend=summarize_backend(backend))


@router.post("/{backend_id}/disable", response_model=BackendMutationResponse)
async def disable_backend(
    backend_id: str,
    service: BackendService = Depends(get_backend_service),
) -> BackendMutationResponse:
    backend = await service.disable_backend(backend_id)
    return BackendMutationResponse(backend=summarize_backend(backend))


@router.post("/{backend_id}/enable", response_model=BackendMutationResponse)
async def enable_backend(
    backend_id: str,
    service: BackendService = Depends(get_backend_service),
) -> BackendMutationResponse:
    backend = await service.enable_backend(backend_id)
    return BackendMutationResponse(backend=summarize_backend(backend))


@router.delete("/{backend_id}", status_code=204)
async def delete_backend(
    backend_id: str,
    service: BackendService = Depends(get_backend_service),
) -> Response:
    await service.delete_backend(backend_id)
    return Response(status_code=204)