from datetime import datetime
from fastapi import APIRouter, Depends, Header, HTTPException, Query
from sqlalchemy.orm import Session

from app.database import get_db
from app.models.db_models import Device, OptionPosition
from app.models.schemas import OptionPositionCreate, OptionPositionClose, OptionPositionResponse

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


def _get_device(x_device_token: str = Header(...), db: Session = Depends(get_db)) -> Device:
    device = db.query(Device).filter(Device.apns_token == x_device_token).first()
    if not device:
        raise HTTPException(status_code=404, detail="Device not registered.")
    return device


@router.get("", response_model=list[OptionPositionResponse])
def get_positions(
    status: str | None = Query(None),
    device: Device = Depends(_get_device),
    db: Session = Depends(get_db),
):
    query = db.query(OptionPosition).filter(OptionPosition.device_id == device.id)
    if status:
        query = query.filter(OptionPosition.status == status)
    return query.order_by(OptionPosition.opened_at.desc()).all()


@router.post("", response_model=OptionPositionResponse, status_code=201)
def log_position(
    body: OptionPositionCreate,
    device: Device = Depends(_get_device),
    db: Session = Depends(get_db),
):
    position = OptionPosition(
        device_id=device.id,
        ticker=body.ticker,
        strategy=body.strategy,
        strike=body.strike,
        expiration=body.expiration,
        premium_received=body.premium_received,
        contracts=body.contracts,
        status="open",
    )
    db.add(position)
    db.commit()
    db.refresh(position)
    return position


@router.patch("/{position_id}", response_model=OptionPositionResponse)
def close_position(
    position_id: int,
    body: OptionPositionClose,
    device: Device = Depends(_get_device),
    db: Session = Depends(get_db),
):
    position = (
        db.query(OptionPosition)
        .filter(OptionPosition.id == position_id, OptionPosition.device_id == device.id)
        .first()
    )
    if not position:
        raise HTTPException(status_code=404, detail="Position not found.")

    valid_statuses = ("closed", "rolled")
    if body.status not in valid_statuses:
        raise HTTPException(status_code=422, detail=f"status must be one of {valid_statuses}")

    position.status = body.status
    position.close_reason = body.close_reason
    position.closed_at = datetime.utcnow()

    db.commit()
    db.refresh(position)
    return position