import os
import psycopg2
from psycopg2.extras import RealDictCursor


def get_db_connection():
    """Get database connection"""
    return psycopg2.connect(
        host=os.getenv("DB_HOST", "localhost"),
        port=int(os.getenv("DB_PORT", "5432")),
        database=os.getenv("DB_NAME", "recipes_db"),
        user=os.getenv("DB_USER", "recipes_user"),
        password=os.getenv("DB_PASSWORD", "recipes_password"),
    )


def create_user(username: str, email: str, password_hash: str, first_name: str = None, last_name: str = None, display_name: str = None, is_admin: bool = False):
    """Create a new user"""
    conn = get_db_connection()
    cur = conn.cursor(cursor_factory=RealDictCursor)
    try:
        # Use display_name if provided, otherwise use username
        final_display_name = display_name if display_name else username
        
        cur.execute(
            """
            INSERT INTO users (username, email, password_hash, first_name, last_name, display_name, is_admin)
            VALUES (%s, %s, %s, %s, %s, %s, %s)
            RETURNING id, username, email, first_name, last_name, display_name, is_admin, created_at
            """,
            (username, email, password_hash, first_name, last_name, final_display_name, is_admin)
        )
        user = cur.fetchone()
        conn.commit()
        return dict(user)
    finally:
        cur.close()
        conn.close()


def get_user_by_username(username: str):
    """Get user by username"""
    conn = get_db_connection()
    cur = conn.cursor(cursor_factory=RealDictCursor)
    try:
        cur.execute(
            "SELECT id, username, email, password_hash, first_name, last_name, display_name, is_admin, created_at FROM users WHERE username = %s",
            (username,)
        )
        user = cur.fetchone()
        return dict(user) if user else None
    finally:
        cur.close()
        conn.close()


def get_user_by_email(email: str):
    """Get user by email"""
    conn = get_db_connection()
    cur = conn.cursor(cursor_factory=RealDictCursor)
    try:
        cur.execute(
            "SELECT id, username, email, password_hash, first_name, last_name, display_name, is_admin, created_at FROM users WHERE email = %s",
            (email,)
        )
        user = cur.fetchone()
        return dict(user) if user else None
    finally:
        cur.close()
        conn.close()


def get_user_by_id(user_id: int):
    """Get user by ID"""
    conn = get_db_connection()
    cur = conn.cursor(cursor_factory=RealDictCursor)
    try:
        cur.execute(
            "SELECT id, username, email, password_hash, first_name, last_name, display_name, is_admin, created_at FROM users WHERE id = %s",
            (user_id,)
        )
        user = cur.fetchone()
        return dict(user) if user else None
    finally:
        cur.close()
        conn.close()


def get_user_by_display_name(display_name: str):
    """Get user by display name"""
    conn = get_db_connection()
    cur = conn.cursor(cursor_factory=RealDictCursor)
    try:
        cur.execute(
            "SELECT id, username, email, display_name, is_admin, created_at FROM users WHERE display_name = %s",
            (display_name,)
        )
        user = cur.fetchone()
        return dict(user) if user else None
    finally:
        cur.close()
        conn.close()