from fastapi import FastAPI, Depends, HTTPException, Query
from sqlalchemy.orm import Session
from models import Base, engine, SessionLocal, Task
from schemas import TaskCreate, TaskResponse

Base.metadata.create_all(bind=engine)
app = FastAPI()

def get_db():
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()

@app.post("/tasks/", response_model=TaskResponse, status_code=201)
def create_task(task: TaskCreate, db: Session = Depends(get_db)):
    db_task = Task(**task.model_dump())
    db.add(db_task)
    db.commit()
    db.refresh(db_task)
    return db_task

@app.get("/tasks/", response_model=list[TaskResponse])
def list_tasks(status: str | None = Query(None), db: Session = Depends(get_db)):
    if status:
        tasks = db.query(Task).filter(Task.status == status).all()
    else:
        tasks = db.query(Task).all()
    return tasks

@app.get("/tasks/{task_id}", response_model=TaskResponse)
def get_task(task_id: int, db: Session = Depends(get_db)):
    task = db.query(Task).filter(Task.id == task_id).first()
    if not task:
        raise HTTPException(status_code=404, detail="Not found")
    return task

@app.put("/tasks/{task_id}", response_model=TaskResponse)
def update_task(task_id: int, task: TaskCreate, db: Session = Depends(get_db)):
    db_task = db.query(Task).filter(Task.id == task_id).first()
    if not db_task:
        raise HTTPException(status_code=404, detail="Not found")
    for key, value in task.model_dump().items():
        setattr(db_task, key, value)
    db.commit()
    db.refresh(db_task)
    return db_task

@app.delete("/tasks/{task_id}", status_code=204)
def delete_task(task_id: int, db: Session = Depends(get_db)):
    db_task = db.query(Task).filter(Task.id == task_id).first()
    if not db_task:
        raise HTTPException(status_code=404, detail="Not found")
    db.delete(db_task)
    db.commit()