from fastapi import APIRouter, Depends, HTTPException, Query
from sqlalchemy.orm import Session
from typing import List, Optional
from app.db.session import get_db
from app.models.task import Task, TaskStatus, TaskPriority
from app.schemas.task import TaskCreate, TaskUpdate, TaskResponse

router = APIRouter(prefix="/tasks", tags=["tasks"])


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


@router.get("/", response_model=List[TaskResponse])
def get_tasks(
    skip: int = Query(0, ge=0, description="Number of tasks to skip"),
    limit: int = Query(100, ge=1, le=1000, description="Number of tasks to return"),
    status: Optional[TaskStatus] = Query(None, description="Filter by task status"),
    priority: Optional[TaskPriority] = Query(
        None, description="Filter by task priority"
    ),
    db: Session = Depends(get_db),
):
    query = db.query(Task)

    if status:
        query = query.filter(Task.status == status)
    if priority:
        query = query.filter(Task.priority == priority)

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


@router.get("/{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="Task not found")
    return task


@router.put("/{task_id}", response_model=TaskResponse)
def update_task(task_id: int, task_update: TaskUpdate, db: Session = Depends(get_db)):
    task = db.query(Task).filter(Task.id == task_id).first()
    if not task:
        raise HTTPException(status_code=404, detail="Task not found")

    update_data = task_update.dict(exclude_unset=True)
    for field, value in update_data.items():
        setattr(task, field, value)

    db.commit()
    db.refresh(task)
    return task


@router.delete("/{task_id}", status_code=204)
def delete_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="Task not found")

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