import uuid
from typing import List, Optional

from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel, Field
from sqlalchemy.orm import Session, selectinload

from game.card import compute_deck_type
from core.database import get_db
from core.dependencies import get_current_user
from core.models import Card as CardModel
from core.models import Deck as DeckModel
from core.models import DeckCard as DeckCardModel
from core.models import User as UserModel

router = APIRouter()


class DeckUpdate(BaseModel):
  name: Optional[str] = Field(None, max_length=64)
  card_ids: Optional[List[str]] = None


@router.get("/decks")
def get_decks(user: UserModel = Depends(get_current_user), db: Session = Depends(get_db)):
  decks = db.query(DeckModel).options(
    selectinload(DeckModel.deck_cards).selectinload(DeckCardModel.card)
  ).filter(
    DeckModel.user_id == user.id,
    DeckModel.deleted == False
  ).order_by(DeckModel.created_at).all()
  result = []
  for deck in decks:
    cards = [dc.card for dc in deck.deck_cards]
    result.append({
      "id": str(deck.id),
      "name": deck.name,
      "card_count": len(cards),
      "total_cost": sum(card.cost for card in cards),
      "times_played": deck.times_played,
      "wins": deck.wins,
      "losses": deck.losses,
      "deck_type": compute_deck_type(cards),
    })
  return result


@router.post("/decks")
def create_deck(user: UserModel = Depends(get_current_user), db: Session = Depends(get_db)):
  count = db.query(DeckModel).filter(DeckModel.user_id == user.id).count()
  deck = DeckModel(id=uuid.uuid4(), user_id=user.id, name=f"Deck #{count + 1}")
  db.add(deck)
  db.commit()
  return {"id": str(deck.id), "name": deck.name, "card_count": 0}


@router.patch("/decks/{deck_id}")
def update_deck(deck_id: str, body: DeckUpdate, user: UserModel = Depends(get_current_user), db: Session = Depends(get_db)):
  deck = db.query(DeckModel).filter(DeckModel.id == uuid.UUID(deck_id), DeckModel.user_id == user.id).first()
  if not deck:
    raise HTTPException(status_code=404, detail="Deck not found")
  if body.name is not None:
    deck.name = body.name
  if body.card_ids is not None:
    db.query(DeckCardModel).filter(DeckCardModel.deck_id == deck.id).delete()
    for card_id in body.card_ids:
      db.add(DeckCardModel(deck_id=deck.id, card_id=uuid.UUID(card_id)))
    if deck.times_played > 0:
      deck.wins = 0
      deck.losses = 0
      deck.times_played = 0
  db.commit()
  return {"id": str(deck.id), "name": deck.name}


@router.delete("/decks/{deck_id}")
def delete_deck(deck_id: str, user: UserModel = Depends(get_current_user), db: Session = Depends(get_db)):
  deck = db.query(DeckModel).filter(DeckModel.id == uuid.UUID(deck_id), DeckModel.user_id == user.id).first()
  if not deck:
    raise HTTPException(status_code=404, detail="Deck not found")
  if deck.times_played > 0:
    deck.deleted = True
  else:
    db.delete(deck)
  db.commit()
  return {"message": "Deleted"}


@router.get("/decks/{deck_id}/cards")
def get_deck_cards(deck_id: str, user: UserModel = Depends(get_current_user), db: Session = Depends(get_db)):
  deck = db.query(DeckModel).filter(DeckModel.id == uuid.UUID(deck_id), DeckModel.user_id == user.id).first()
  if not deck:
    raise HTTPException(status_code=404, detail="Deck not found")
  deck_cards = db.query(DeckCardModel).options(
    selectinload(DeckCardModel.card)
  ).filter(DeckCardModel.deck_id == deck.id).all()
  return [{"id": str(dc.card_id), "cost": dc.card.cost} for dc in deck_cards]