from typing import List

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

from app.db.session import get_db
from app.models.todo import Todo
from app.schemas.todo import TodoCreate, TodoResponse, TodoUpdate

router = APIRouter()


@router.post("", response_model=TodoResponse, status_code=status.HTTP_201_CREATED)
def create_todo(todo_in: TodoCreate, db: Session = Depends(get_db)) -> TodoResponse:
    """Create a new todo item."""
    db_todo = Todo(
        title=todo_in.title,
        description=todo_in.description,
        completed=todo_in.completed,
    )
    db.add(db_todo)
    db.commit()
    db.refresh(db_todo)
    return db_todo


@router.get("", response_model=List[TodoResponse])
def read_todos(
    skip: int = 0,
    limit: int = 100,
    db: Session = Depends(get_db),
) -> List[TodoResponse]:
    """Read all todo items with pagination."""
    todos = db.query(Todo).offset(skip).limit(limit).all()
    return todos


@router.get("/{todo_id}", response_model=TodoResponse)
def read_todo(todo_id: int, db: Session = Depends(get_db)) -> TodoResponse:
    """Read a specific todo item by ID."""
    db_todo = db.query(Todo).filter(Todo.id == todo_id).first()
    if db_todo is None:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Todo not found")
    return db_todo


@router.put("/{todo_id}", response_model=TodoResponse)
def update_todo(
    todo_id: int,
    todo_in: TodoUpdate,
    db: Session = Depends(get_db),
) -> TodoResponse:
    """Update a todo item."""
    db_todo = db.query(Todo).filter(Todo.id == todo_id).first()
    if db_todo is None:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Todo not found")

    update_data = todo_in.model_dump(exclude_unset=True)
    for field, value in update_data.items():
        setattr(db_todo, field, value)

    db.commit()
    db.refresh(db_todo)
    return db_todo


@router.delete("/{todo_id}", status_code=status.HTTP_204_NO_CONTENT, response_model=None)
def delete_todo(todo_id: int, db: Session = Depends(get_db)) -> None:
    """Delete a todo item."""
    db_todo = db.query(Todo).filter(Todo.id == todo_id).first()
    if db_todo is None:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Todo not found")

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