import sqlite3
import logging
from typing import Optional, List, Dict, Any
from config import DATABASE_PATH

logger = logging.getLogger(__name__)

class Database:
    def __init__(self, db_path: str = DATABASE_PATH):
        self.db_path = db_path
        self.init_database()
    
    def init_database(self):
        """Initialize database tables"""
        with sqlite3.connect(self.db_path) as conn:
            cursor = conn.cursor()
            
            # Create telegram_users table (Telegram bot users)
            cursor.execute('''
                CREATE TABLE IF NOT EXISTS telegram_users (
                    user_id INTEGER PRIMARY KEY,
                    username TEXT,
                    first_name TEXT,
                    last_name TEXT,
                    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
                )
            ''')
            
            # Create gamers table (Lichess players only)
            cursor.execute('''
                CREATE TABLE IF NOT EXISTS gamers (
                    id INTEGER PRIMARY KEY AUTOINCREMENT,
                    username TEXT UNIQUE NOT NULL,
                    token TEXT,
                    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
                )
            ''')
            
            # Create user_gamers table (relationship between users and gamers)
            cursor.execute('''
                CREATE TABLE IF NOT EXISTS user_gamers (
                    id INTEGER PRIMARY KEY AUTOINCREMENT,
                    user_id INTEGER NOT NULL,
                    gamer_id INTEGER NOT NULL,
                    token TEXT,
                    is_active BOOLEAN DEFAULT FALSE,
                    period_minutes INTEGER DEFAULT 0,
                    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
                    FOREIGN KEY (user_id) REFERENCES telegram_users(user_id),
                    FOREIGN KEY (gamer_id) REFERENCES gamers(id),
                    UNIQUE(user_id, gamer_id)
                )
            ''')
            
            # Add token column to user_gamers if it doesn't exist
            try:
                cursor.execute("ALTER TABLE user_gamers ADD COLUMN token TEXT")
            except sqlite3.OperationalError:
                # Column already exists
                pass
            
            conn.commit()
            
            # Migrate tokens from gamers to user_gamers if needed
            self._migrate_tokens_from_gamers()
            
            logger.info("Database initialized successfully")
    
    def _migrate_tokens_from_gamers(self):
        """Migrate tokens from old gamers table to user_gamers table if needed"""
        with sqlite3.connect(self.db_path) as conn:
            cursor = conn.cursor()
            
            # Check if there are tokens in gamers table that need migration
            cursor.execute("SELECT COUNT(*) FROM gamers WHERE token IS NOT NULL")
            gamers_with_tokens = cursor.fetchone()[0]
            
            if gamers_with_tokens == 0:
                return  # No tokens to migrate
            
            # Check if user_gamers already has tokens
            cursor.execute("SELECT COUNT(*) FROM user_gamers WHERE token IS NOT NULL")
            user_gamers_with_tokens = cursor.fetchone()[0]
            
            if user_gamers_with_tokens > 0:
                return  # Migration already done
            
            # Migrate tokens from gamers to user_gamers
            cursor.execute("SELECT id, token FROM gamers WHERE token IS NOT NULL")
            gamers_tokens = cursor.fetchall()
            
            migrated = 0
            for gamer_id, token in gamers_tokens:
                # Update all user-gamer relationships for this gamer
                cursor.execute(
                    "UPDATE user_gamers SET token = ? WHERE gamer_id = ? AND token IS NULL",
                    (token, gamer_id)
                )
                migrated += cursor.rowcount
            
            conn.commit()
            
            if migrated > 0:
                logger.info(f"Migrated {migrated} tokens from gamers to user_gamers")
    
    def add_or_get_telegram_user(self, user_id: int, username: Optional[str] = None, 
                                  first_name: Optional[str] = None, last_name: Optional[str] = None) -> bool:
        """Add or update Telegram user"""
        with sqlite3.connect(self.db_path) as conn:
            cursor = conn.cursor()
            
            cursor.execute("SELECT user_id FROM telegram_users WHERE user_id = ?", (user_id,))
            existing = cursor.fetchone()
            
            if not existing:
                cursor.execute(
                    "INSERT INTO telegram_users (user_id, username, first_name, last_name) VALUES (?, ?, ?, ?)",
                    (user_id, username, first_name, last_name)
                )
                conn.commit()
                return True
            return False
    
    def add_gamer(self, username: str) -> int:
        """Add a new gamer to the database (return gamer_id)"""
        with sqlite3.connect(self.db_path) as conn:
            cursor = conn.cursor()
            
            # Check if gamer already exists
            cursor.execute("SELECT id FROM gamers WHERE username = ?", (username,))
            existing = cursor.fetchone()
            
            if existing:
                gamer_id = existing[0]
            else:
                # Add new gamer (without token - tokens are stored in user_gamers)
                cursor.execute(
                    "INSERT INTO gamers (username) VALUES (?)",
                    (username,)
                )
                gamer_id = cursor.lastrowid
            
            conn.commit()
            return gamer_id
    
    def add_user_gamer(self, user_id: int, gamer_id: int, token: Optional[str] = None) -> bool:
        """Add relationship between user and gamer with optional token"""
        with sqlite3.connect(self.db_path) as conn:
            cursor = conn.cursor()
            
            try:
                cursor.execute(
                    "INSERT INTO user_gamers (user_id, gamer_id, token) VALUES (?, ?, ?)",
                    (user_id, gamer_id, token)
                )
                conn.commit()
                return True
            except sqlite3.IntegrityError:
                # Already exists - update token if provided
                if token:
                    cursor.execute(
                        "UPDATE user_gamers SET token = ? WHERE user_id = ? AND gamer_id = ?",
                        (token, user_id, gamer_id)
                    )
                    conn.commit()
                return False
    
    def get_user_gamers(self, user_id: int) -> List[Dict[str, Any]]:
        """Get all gamers for a specific user"""
        with sqlite3.connect(self.db_path) as conn:
            cursor = conn.cursor()
            cursor.execute('''
                SELECT g.id, g.username, ug.token, ug.is_active, ug.period_minutes
                FROM user_gamers ug
                JOIN gamers g ON ug.gamer_id = g.id
                WHERE ug.user_id = ?
                ORDER BY ug.id
            ''', (user_id,))
            
            gamers = []
            for row in cursor.fetchall():
                gamers.append({
                    'id': row[0],
                    'username': row[1],
                    'token': row[2],  # Token from user_gamers, not gamers
                    'is_active': bool(row[3]),
                    'period_minutes': row[4]
                })
            
            return gamers
    
    def get_user_active_gamer(self, user_id: int) -> Optional[Dict[str, Any]]:
        """Get the active gamer for a specific user"""
        with sqlite3.connect(self.db_path) as conn:
            cursor = conn.cursor()
            cursor.execute('''
                SELECT g.id, g.username, ug.token
                FROM user_gamers ug
                JOIN gamers g ON ug.gamer_id = g.id
                WHERE ug.user_id = ? AND ug.is_active = TRUE
                LIMIT 1
            ''', (user_id,))
            
            row = cursor.fetchone()
            if row:
                return {
                    'id': row[0],
                    'username': row[1],
                    'token': row[2]  # Token from user_gamers
                }
            return None
    
    def set_user_active_gamer(self, user_id: int, gamer_id: int):
        """Set active gamer for a specific user"""
        with sqlite3.connect(self.db_path) as conn:
            cursor = conn.cursor()
            
            # Deactivate all gamers for this user
            cursor.execute(
                "UPDATE user_gamers SET is_active = FALSE WHERE user_id = ?",
                (user_id,)
            )
            
            # Activate the selected gamer
            cursor.execute(
                "UPDATE user_gamers SET is_active = TRUE WHERE user_id = ? AND gamer_id = ?",
                (user_id, gamer_id)
            )
            
            conn.commit()
    
    def set_user_gamer_period(self, user_id: int, gamer_id: int, period_minutes: int):
        """Set period for a gamer for a specific user"""
        with sqlite3.connect(self.db_path) as conn:
            cursor = conn.cursor()
            cursor.execute(
                "UPDATE user_gamers SET period_minutes = ? WHERE user_id = ? AND gamer_id = ?",
                (period_minutes, user_id, gamer_id)
            )
            conn.commit()
    
    def get_user_gamers_with_periods(self, user_id: int) -> List[Dict[str, Any]]:
        """Get all gamers for a user that have periods set"""
        with sqlite3.connect(self.db_path) as conn:
            cursor = conn.cursor()
            cursor.execute('''
                SELECT g.id, g.username, ug.token, ug.period_minutes
                FROM user_gamers ug
                JOIN gamers g ON ug.gamer_id = g.id
                WHERE ug.user_id = ? AND ug.period_minutes > 0
            ''', (user_id,))
            
            gamers = []
            for row in cursor.fetchall():
                gamers.append({
                    'id': row[0],
                    'username': row[1],
                    'token': row[2],  # Token from user_gamers
                    'period_minutes': row[3]
                })
            
            return gamers
    
    def get_all_gamers_with_periods(self) -> List[Dict[str, Any]]:
        """Get all user-gamer pairs that have periods set (for periodic checks across all users)"""
        with sqlite3.connect(self.db_path) as conn:
            cursor = conn.cursor()
            cursor.execute('''
                SELECT ug.user_id, g.id, g.username, ug.token, ug.period_minutes
                FROM user_gamers ug
                JOIN gamers g ON ug.gamer_id = g.id
                WHERE ug.period_minutes > 0
            ''')
            
            gamers = []
            for row in cursor.fetchall():
                gamers.append({
                    'user_id': row[0],
                    'id': row[1],
                    'username': row[2],
                    'token': row[3],  # Token from user_gamers
                    'period_minutes': row[4]
                })
            
            return gamers