import uuid

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

from app.core.deps import get_current_user, get_db_session, require_study_member, require_study_roles
from app.crud import audit as audit_crud
from app.crud import imp_batch as batch_crud
from app.crud import study as study_crud
from app.schemas.imp import BatchCreate, BatchRead, BatchUpdate

router = APIRouter()


async def _ensure_study_exists(db: AsyncSession, study_id: uuid.UUID):
    study = await study_crud.get(db, study_id)
    if not study:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Study not found")
    return study


@router.post(
    "/",
    response_model=BatchRead,
    status_code=status.HTTP_201_CREATED,
    dependencies=[Depends(require_study_roles(["PM", "IMP"]))],
)
async def create_batch(
    study_id: uuid.UUID,
    batch_in: BatchCreate,
    db: AsyncSession = Depends(get_db_session),
    current_user=Depends(get_current_user),
) -> BatchRead:
    await _ensure_study_exists(db, study_id)
    try:
        batch = await batch_crud.create_batch(db, study_id, batch_in)
    except ValueError as exc:
        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(exc)) from exc
    await audit_crud.log_action(
        db,
        study_id=study_id,
        entity_type="imp_batch",
        entity_id=batch.id,
        action="CREATE_IMP_BATCH",
        detail=f"IMP batch {batch.batch_no} created",
        operator_id=current_user.id,
        operator_role=current_user.role,
    )
    return BatchRead.model_validate(batch)


@router.get(
    "/",
    response_model=list[BatchRead],
    dependencies=[Depends(require_study_member())],
)
async def list_batches(
    study_id: uuid.UUID,
    product_id: uuid.UUID | None = None,
    status_filter: str | None = None,
    db: AsyncSession = Depends(get_db_session),
) -> list[BatchRead]:
    await _ensure_study_exists(db, study_id)
    batches = await batch_crud.list_batches(db, study_id, product_id=product_id, status=status_filter)
    return [BatchRead.model_validate(b) for b in batches]


@router.patch(
    "/{batch_id}",
    response_model=BatchRead,
    dependencies=[Depends(require_study_roles(["PM", "IMP"]))],
)
async def update_batch(
    study_id: uuid.UUID,
    batch_id: uuid.UUID,
    batch_in: BatchUpdate,
    db: AsyncSession = Depends(get_db_session),
    current_user=Depends(get_current_user),
) -> BatchRead:
    await _ensure_study_exists(db, study_id)
    batch = await batch_crud.get_batch(db, batch_id)
    if not batch or batch.study_id != study_id:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Batch not found")
    updated = await batch_crud.update_batch(db, batch, batch_in)
    await audit_crud.log_action(
        db,
        study_id=study_id,
        entity_type="imp_batch",
        entity_id=batch_id,
        action="UPDATE_IMP_BATCH",
        detail=f"IMP batch {batch_id} updated",
        operator_id=current_user.id,
        operator_role=current_user.role,
    )
    return BatchRead.model_validate(updated)