from typing import Any, List, Optional

from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.orm import Session

from app import crud, schemas
from app.db.session import get_db
from app.models.inventory_movement import MovementType

router = APIRouter()


@router.get("/movements/", response_model=List[schemas.InventoryMovementWithProduct])
def read_inventory_movements(
    db: Session = Depends(get_db),
    skip: int = 0,
    limit: int = 100,
    product_id: Optional[str] = None,
    movement_type: Optional[schemas.MovementTypeEnum] = None,
) -> Any:
    """
    Retrieve inventory movements with optional filtering.
    """
    if movement_type:
        db_movement_type = MovementType(movement_type)
    else:
        db_movement_type = None

    movements = crud.inventory.get_multi(
        db, skip=skip, limit=limit, product_id=product_id, movement_type=db_movement_type
    )
    return movements


@router.post(
    "/movements/", response_model=schemas.InventoryMovement, status_code=status.HTTP_201_CREATED
)
def create_inventory_movement(
    *,
    db: Session = Depends(get_db),
    movement_in: schemas.InventoryMovementCreate,
) -> Any:
    """
    Create a new inventory movement (stock in, stock out, adjustment, return).
    """
    # Check if product exists
    product = crud.product.get(db, product_id=movement_in.product_id)
    if not product:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Product not found",
        )

    # For stock out, check if there is enough stock
    if (
        movement_in.type == schemas.MovementTypeEnum.STOCK_OUT
        and product.current_stock < movement_in.quantity
    ):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=f"Insufficient stock for product {product.name}. Available: {product.current_stock}, Requested: {movement_in.quantity}",
        )

    try:
        movement = crud.inventory.create(db, obj_in=movement_in)
        return movement
    except ValueError as e:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=str(e),
        ) from e


@router.get("/movements/{movement_id}", response_model=schemas.InventoryMovementWithProduct)
def read_inventory_movement(
    *,
    db: Session = Depends(get_db),
    movement_id: str,
) -> Any:
    """
    Get a specific inventory movement by ID.
    """
    movement = crud.inventory.get(db, movement_id=movement_id)
    if not movement:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Inventory movement not found",
        )
    return movement


@router.delete(
    "/movements/{movement_id}", status_code=status.HTTP_204_NO_CONTENT, response_model=None
)
def delete_inventory_movement(
    *,
    db: Session = Depends(get_db),
    movement_id: str,
) -> Any:
    """
    Delete an inventory movement and revert its effect on stock.
    Warning: This will alter inventory history and may cause inconsistencies.
    Consider using adjustments instead for corrections.
    """
    movement = crud.inventory.get(db, movement_id=movement_id)
    if not movement:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Inventory movement not found",
        )

    try:
        crud.inventory.remove(db, movement_id=movement_id)
        return None
    except ValueError as e:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=str(e),
        ) from e