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

from app.db.session import get_db
from app.models import models
from app.schemas.item import Item, ItemCreate, ItemUpdate

router = APIRouter()


@router.post("/items/", response_model=Item, status_code=status.HTTP_201_CREATED)
def create_item(item: ItemCreate, db: Session = Depends(get_db)):
    """
    Create a new item.

    Args:
        item: The item data to create
        db: Database session

    Returns:
        The created item
    """
    db_item = models.Item(**item.model_dump())
    db.add(db_item)
    db.commit()
    db.refresh(db_item)
    return db_item


@router.get("/items/", response_model=List[Item])
def read_items(
    skip: int = 0,
    limit: int = 100,
    name: Optional[str] = None,
    db: Session = Depends(get_db),
):
    """
    Retrieve items with optional filtering.

    Args:
        skip: Number of items to skip
        limit: Maximum number of items to return
        name: Optional filter by item name
        db: Database session

    Returns:
        List of items
    """
    query = db.query(models.Item)

    if name:
        query = query.filter(models.Item.name.ilike(f"%{name}%"))

    items = query.offset(skip).limit(limit).all()
    return items


@router.get("/items/{item_id}", response_model=Item)
def read_item(item_id: int, db: Session = Depends(get_db)):
    """
    Get item by ID.

    Args:
        item_id: The ID of the item to retrieve
        db: Database session

    Returns:
        The requested item

    Raises:
        HTTPException: If item is not found
    """
    item = db.query(models.Item).filter(models.Item.id == item_id).first()
    if item is None:
        raise HTTPException(status_code=404, detail="Item not found")
    return item


@router.patch("/items/{item_id}", response_model=Item)
def update_item(item_id: int, item_update: ItemUpdate, db: Session = Depends(get_db)):
    """
    Update an item.

    Args:
        item_id: The ID of the item to update
        item_update: The updated item data
        db: Database session

    Returns:
        The updated item

    Raises:
        HTTPException: If item is not found
    """
    db_item = db.query(models.Item).filter(models.Item.id == item_id).first()
    if db_item is None:
        raise HTTPException(status_code=404, detail="Item not found")

    # Update item attributes that are provided
    update_data = item_update.model_dump(exclude_unset=True)
    for key, value in update_data.items():
        setattr(db_item, key, value)

    db.commit()
    db.refresh(db_item)
    return db_item


@router.delete(
    "/items/{item_id}", status_code=status.HTTP_204_NO_CONTENT, response_model=None
)
def delete_item(item_id: int, db: Session = Depends(get_db)):
    """
    Delete an item.

    Args:
        item_id: The ID of the item to delete
        db: Database session

    Returns:
        None

    Raises:
        HTTPException: If item is not found
    """
    db_item = db.query(models.Item).filter(models.Item.id == item_id).first()
    if db_item is None:
        raise HTTPException(status_code=404, detail="Item not found")

    db.delete(db_item)
    db.commit()
    return None