"""
Database Operations - Async persistence layer for game data.

Provides async operations for persisting and retrieving game data.
Used by StateManager for database persistence and recovery.

Author: Claude
Date: 2025-10-22
"""

import logging
from typing import Optional, List, Dict
from uuid import UUID
from sqlalchemy import select
from sqlalchemy.orm import joinedload

from app.database.session import AsyncSessionLocal
from app.models.db_models import Game, Play, Lineup, GameSession

logger = logging.getLogger(f'{__name__}.DatabaseOperations')


class DatabaseOperations:
    """
    Async database operations for game persistence.

    Provides methods for creating, reading, and updating game data in PostgreSQL.
    All operations are async and use the AsyncSessionLocal for session management.
    """

    async def create_game(
        self,
        game_id: UUID,
        league_id: str,
        home_team_id: int,
        away_team_id: int,
        game_mode: str,
        visibility: str,
        home_team_is_ai: bool = False,
        away_team_is_ai: bool = False,
        ai_difficulty: Optional[str] = None
    ) -> Game:
        """
        Create new game in database.

        Args:
            game_id: Unique game identifier
            league_id: League identifier ('sba' or 'pd')
            home_team_id: Home team ID
            away_team_id: Away team ID
            game_mode: Game mode ('ranked', 'friendly', 'practice')
            visibility: Visibility ('public', 'private')
            home_team_is_ai: Whether home team is AI
            away_team_is_ai: Whether away team is AI
            ai_difficulty: AI difficulty if applicable

        Returns:
            Created Game model

        Raises:
            SQLAlchemyError: If database operation fails
        """
        async with AsyncSessionLocal() as session:
            try:
                game = Game(
                    id=game_id,
                    league_id=league_id,
                    home_team_id=home_team_id,
                    away_team_id=away_team_id,
                    game_mode=game_mode,
                    visibility=visibility,
                    home_team_is_ai=home_team_is_ai,
                    away_team_is_ai=away_team_is_ai,
                    ai_difficulty=ai_difficulty,
                    status="pending"
                )
                session.add(game)
                await session.commit()
                await session.refresh(game)
                logger.info(f"Created game {game_id} in database ({league_id})")
                return game
            except Exception as e:
                await session.rollback()
                logger.error(f"Failed to create game {game_id}: {e}")
                raise

    async def get_game(self, game_id: UUID) -> Optional[Game]:
        """
        Get game by ID.

        Args:
            game_id: Game identifier

        Returns:
            Game model if found, None otherwise
        """
        async with AsyncSessionLocal() as session:
            result = await session.execute(
                select(Game).where(Game.id == game_id)
            )
            game = result.scalar_one_or_none()
            if game:
                logger.debug(f"Retrieved game {game_id} from database")
            return game

    async def update_game_state(
        self,
        game_id: UUID,
        inning: int,
        half: str,
        home_score: int,
        away_score: int,
        status: Optional[str] = None
    ) -> None:
        """
        Update game state fields.

        Args:
            game_id: Game identifier
            inning: Current inning
            half: Current half ('top' or 'bottom')
            home_score: Home team score
            away_score: Away team score
            status: Game status if updating

        Raises:
            ValueError: If game not found
        """
        async with AsyncSessionLocal() as session:
            try:
                result = await session.execute(
                    select(Game).where(Game.id == game_id)
                )
                game = result.scalar_one_or_none()

                if not game:
                    raise ValueError(f"Game {game_id} not found")

                game.current_inning = inning
                game.current_half = half
                game.home_score = home_score
                game.away_score = away_score

                if status:
                    game.status = status

                await session.commit()
                logger.debug(f"Updated game {game_id} state (inning {inning}, {half})")

            except Exception as e:
                await session.rollback()
                logger.error(f"Failed to update game {game_id} state: {e}")
                raise

    async def create_lineup_entry(
        self,
        game_id: UUID,
        team_id: int,
        card_id: int,
        position: str,
        batting_order: Optional[int] = None,
        is_starter: bool = True
    ) -> Lineup:
        """
        Create lineup entry in database.

        Args:
            game_id: Game identifier
            team_id: Team identifier
            card_id: Player card ID
            position: Player position
            batting_order: Batting order (1-9) if applicable
            is_starter: Whether player is starting lineup

        Returns:
            Created Lineup model

        Raises:
            SQLAlchemyError: If database operation fails
        """
        async with AsyncSessionLocal() as session:
            try:
                lineup = Lineup(
                    game_id=game_id,
                    team_id=team_id,
                    card_id=card_id,
                    position=position,
                    batting_order=batting_order,
                    is_starter=is_starter,
                    is_active=True
                )
                session.add(lineup)
                await session.commit()
                await session.refresh(lineup)
                logger.debug(f"Created lineup entry for card {card_id} in game {game_id}")
                return lineup

            except Exception as e:
                await session.rollback()
                logger.error(f"Failed to create lineup entry: {e}")
                raise

    async def get_active_lineup(self, game_id: UUID, team_id: int) -> List[Lineup]:
        """
        Get active lineup for team.

        Args:
            game_id: Game identifier
            team_id: Team identifier

        Returns:
            List of active Lineup models, sorted by batting order
        """
        async with AsyncSessionLocal() as session:
            result = await session.execute(
                select(Lineup)
                .where(
                    Lineup.game_id == game_id,
                    Lineup.team_id == team_id,
                    Lineup.is_active == True
                )
                .order_by(Lineup.batting_order)
            )
            lineups = list(result.scalars().all())
            logger.debug(f"Retrieved {len(lineups)} active lineup entries for team {team_id}")
            return lineups

    async def save_play(self, play_data: dict) -> Play:
        """
        Save play to database.

        Args:
            play_data: Dictionary with play data matching Play model fields

        Returns:
            Created Play model

        Raises:
            SQLAlchemyError: If database operation fails
        """
        async with AsyncSessionLocal() as session:
            try:
                play = Play(**play_data)
                session.add(play)
                await session.commit()
                await session.refresh(play)
                logger.info(f"Saved play {play.play_number} for game {play.game_id}")
                return play

            except Exception as e:
                await session.rollback()
                logger.error(f"Failed to save play: {e}")
                raise

    async def get_plays(self, game_id: UUID) -> List[Play]:
        """
        Get all plays for game.

        Args:
            game_id: Game identifier

        Returns:
            List of Play models, ordered by play_number
        """
        async with AsyncSessionLocal() as session:
            result = await session.execute(
                select(Play)
                .where(Play.game_id == game_id)
                .order_by(Play.play_number)
            )
            plays = list(result.scalars().all())
            logger.debug(f"Retrieved {len(plays)} plays for game {game_id}")
            return plays

    async def load_game_state(self, game_id: UUID) -> Optional[Dict]:
        """
        Load complete game state for recovery.

        Loads game, lineups, and plays in a single transaction.

        Args:
            game_id: Game identifier

        Returns:
            Dictionary with 'game', 'lineups', and 'plays' keys, or None if game not found
        """
        async with AsyncSessionLocal() as session:
            # Get game
            game_result = await session.execute(
                select(Game).where(Game.id == game_id)
            )
            game = game_result.scalar_one_or_none()

            if not game:
                logger.warning(f"Game {game_id} not found for recovery")
                return None

            # Get lineups
            lineup_result = await session.execute(
                select(Lineup)
                .where(Lineup.game_id == game_id, Lineup.is_active == True)
            )
            lineups = list(lineup_result.scalars().all())

            # Get plays
            play_result = await session.execute(
                select(Play)
                .where(Play.game_id == game_id)
                .order_by(Play.play_number)
            )
            plays = list(play_result.scalars().all())

            logger.info(f"Loaded game state for {game_id}: {len(lineups)} lineups, {len(plays)} plays")

            return {
                'game': {
                    'id': game.id,
                    'league_id': game.league_id,
                    'home_team_id': game.home_team_id,
                    'away_team_id': game.away_team_id,
                    'home_team_is_ai': game.home_team_is_ai,
                    'away_team_is_ai': game.away_team_is_ai,
                    'status': game.status,
                    'current_inning': game.current_inning,
                    'current_half': game.current_half,
                    'home_score': game.home_score,
                    'away_score': game.away_score
                },
                'lineups': [
                    {
                        'id': l.id,
                        'team_id': l.team_id,
                        'card_id': l.card_id,
                        'position': l.position,
                        'batting_order': l.batting_order,
                        'is_active': l.is_active
                    }
                    for l in lineups
                ],
                'plays': [
                    {
                        'play_number': p.play_number,
                        'inning': p.inning,
                        'half': p.half,
                        'outs_before': p.outs_before,
                        'result_description': p.result_description
                    }
                    for p in plays
                ]
            }

    async def create_game_session(self, game_id: UUID) -> GameSession:
        """
        Create game session record for WebSocket tracking.

        Args:
            game_id: Game identifier

        Returns:
            Created GameSession model
        """
        async with AsyncSessionLocal() as session:
            try:
                game_session = GameSession(game_id=game_id)
                session.add(game_session)
                await session.commit()
                await session.refresh(game_session)
                logger.info(f"Created game session for {game_id}")
                return game_session

            except Exception as e:
                await session.rollback()
                logger.error(f"Failed to create game session: {e}")
                raise

    async def update_session_snapshot(
        self,
        game_id: UUID,
        state_snapshot: dict
    ) -> None:
        """
        Update session state snapshot.

        Args:
            game_id: Game identifier
            state_snapshot: JSON-serializable state snapshot

        Raises:
            ValueError: If game session not found
        """
        async with AsyncSessionLocal() as session:
            try:
                result = await session.execute(
                    select(GameSession).where(GameSession.game_id == game_id)
                )
                game_session = result.scalar_one_or_none()

                if not game_session:
                    raise ValueError(f"Game session {game_id} not found")

                game_session.state_snapshot = state_snapshot
                await session.commit()
                logger.debug(f"Updated session snapshot for {game_id}")

            except Exception as e:
                await session.rollback()
                logger.error(f"Failed to update session snapshot: {e}")
                raise