from multiprocessing import connection

from fastapi import HTTPException
from ..db import get_connection
from ..utils.jwt_handler import verify_token
import hashlib


def query_users_by_range(token: str, start: int, end: int):
    """
    1. 验证 token 是否有效，以及是否是 admin 用户
    2. 查询 user_id 在 [start, end] 范围内的用户
    3. 返回用户的基本信息
    """
    # 1. 验证 token
    try:
        payload = verify_token(token)  # 如果验证失败会抛出异常
        username = payload["sub"]
    except ValueError as e:
        raise HTTPException(status_code=401, detail=str(e))

    # 2. 确认用户类型是否为 admin
    connection = get_connection()
    if not connection:
        raise HTTPException(status_code=500, detail="Database connection failed!")

    try:
        cursor = connection.cursor(dictionary=True)
        cursor.execute("SELECT user_type FROM users WHERE username = %s;", (username,))
        admin_user = cursor.fetchone()

        if not admin_user:
            raise HTTPException(status_code=401, detail="Admin user not found.")
        if admin_user["user_type"] != "admin":
            raise HTTPException(status_code=403, detail="Permission denied: Not an admin user.")

        # 3. 查询范围内的用户
        cursor.execute("""
            SELECT 
                user_id,
                username,
                points,
                phone_number,
                gender,
                email,
                user_type,
                created_at,
                updated_at
            FROM users
            WHERE user_id BETWEEN %s AND %s
            ORDER BY user_id ASC
        """, (start, end))
        result = cursor.fetchall()

        # 4. 返回结果
        return result

    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error during query: {str(e)}")
    finally:
        cursor.close()
        connection.close()

def delete_user_by_token(token: str, uid: int):
    """
    删除用户逻辑：
    1. 验证 token 确保为管理员。
    2. 检查指定用户是否存在。
    3. 检查用户是否有相关订单信息。
    4. 删除用户。
    """
    # 1. 验证 token
    try:
        payload = verify_token(token)  # 如果验证失败会抛出异常
        username = payload["sub"]
    except ValueError as e:
        raise HTTPException(status_code=401, detail=str(e))

    # 2. 确认用户类型是否为 admin
    connection = get_connection()
    if not connection:
        raise HTTPException(status_code=500, detail="Database connection failed!")

    try:
        cursor = connection.cursor(dictionary=True)
        cursor.execute("SELECT user_type FROM users WHERE username = %s;", (username,))
        admin_user = cursor.fetchone()

        if not admin_user:
            raise HTTPException(status_code=401, detail="Admin user not found.")
        if admin_user["user_type"] != "admin":
            raise HTTPException(status_code=403, detail="Permission denied: Not an admin user.")

        # 3. 检查用户是否存在
        cursor.execute("SELECT * FROM users WHERE user_id = %s;", (uid,))
        user_to_delete = cursor.fetchone()

        if not user_to_delete:
            raise HTTPException(status_code=404, detail=f"User with ID {uid} not found.")

        # 4. 检查用户是否有订单
        cursor.execute("SELECT COUNT(*) AS order_count FROM orders WHERE user_id = %s;", (uid,))
        order_info = cursor.fetchone()

        if order_info["order_count"] > 0:
            raise HTTPException(status_code=400, detail=f"Cannot delete user with ID {uid}: user has existing orders.")

        # 5. 删除用户
        cursor.execute("DELETE FROM users WHERE user_id = %s;", (uid,))
        connection.commit()

        return f"User with ID {uid} deleted successfully."

    # except Exception as e:
    #     raise HTTPException(status_code=500, detail=f"Error during deletion: {str(e)}")
    finally:
        cursor.close()
        connection.close()


def update_user(token: str, uid: int, username: str = None, email: str = None,
                phone_number: str = None, gender: str = None, user_type: str = None):
    """
    管理员更新用户信息：
    1. 验证 token 确保为管理员。
    2. 确认用户存在。
    3. 根据提供的参数更新用户信息。
    """
    # 1. 验证 token
    try:
        payload = verify_token(token)  # 如果验证失败会抛出异常
        admin_username = payload["sub"]
    except ValueError as e:
        raise HTTPException(status_code=401, detail=str(e))

    # 2. 确认管理员权限
    connection = get_connection()
    if not connection:
        raise HTTPException(status_code=500, detail="Database connection failed!")

    try:
        cursor = connection.cursor(dictionary=True)
        cursor.execute("SELECT user_type FROM users WHERE username = %s;", (admin_username,))
        admin_user = cursor.fetchone()

        if not admin_user:
            raise HTTPException(status_code=401, detail="Admin user not found.")
        if admin_user["user_type"] != "admin":
            raise HTTPException(status_code=403, detail="Permission denied: Not an admin user.")

        # 3. 检查用户是否存在
        cursor.execute("SELECT * FROM users WHERE user_id = %s;", (uid,))
        user_to_update = cursor.fetchone()

        if not user_to_update:
            raise HTTPException(status_code=404, detail=f"User with ID {uid} not found.")

        # 4. 根据提供的字段更新用户信息
        updates = []
        params = []

        print(username, email, phone_number, gender, user_type)

        if username:
            updates.append("username = %s")
            params.append(username)
        if email:
            updates.append("email = %s")
            params.append(email)
        if phone_number:
            updates.append("phone_number = %s")
            params.append(phone_number)
        if gender:
            updates.append("gender = %s")
            params.append(gender)
        if user_type:
            if user_type not in ['admin', 'player']:
                raise HTTPException(status_code=400, detail="Invalid user_type. Must be 'admin' or 'player'.")
            updates.append("user_type = %s")
            params.append(user_type)

        if not updates:
            raise HTTPException(status_code=400, detail="No fields to update.")

        params.append(uid)
        update_query = f"UPDATE users SET {', '.join(updates)} WHERE user_id = %s;"

        # 5. 执行更新操作
        cursor.execute(update_query, tuple(params))
        connection.commit()

        return f"User with ID {uid} updated successfully."

    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error during update: {str(e)}")
    finally:
        cursor.close()
        connection.close()

def get_total_of_users(token: str):
    """
    获取用户总数
    1. 验证 token 确保为管理员。
    2. 查询总人数
    """
    # 1. 验证 token
    try:
        payload = verify_token(token)  # 如果验证失败会抛出异常
        admin_username = payload["sub"]
    except ValueError as e:
        raise HTTPException(status_code=401, detail=str(e))

    connection = get_connection()
    if not connection:
        raise HTTPException(status_code=500, detail="Database connection failed!")

    try:
        cursor = connection.cursor(dictionary=True)
        cursor.execute("SELECT user_type FROM users WHERE username = %s;", (admin_username,))
        admin_user = cursor.fetchone()

        if not admin_user:
            raise HTTPException(status_code=401, detail="Admin user not found.")
        if admin_user["user_type"] != "admin":
            raise HTTPException(status_code=403, detail="Permission denied: Not an admin user.")

        cursor.execute("SELECT COUNT(*) AS user_count FROM users")
        result = cursor.fetchone()
        if not result:
            raise HTTPException(status_code=404, detail="Database connection failed!")
        return result["user_count"]
    finally:
        cursor.close()
        connection.close()

def query_user(token: str, query_mode: str, query_value: str):
    """
    通过 `phone_number` / `email` / `username` / `uid` 进行模糊查询
    """
    # 1. 验证 token
    try:
        payload = verify_token(token)
        username = payload["sub"]
    except ValueError as e:
        raise HTTPException(status_code=401, detail=str(e))

    # 2. 确认管理员身份
    connection = get_connection()
    if not connection:
        raise HTTPException(status_code=500, detail="Database connection failed!")

    try:
        cursor = connection.cursor(dictionary=True)
        cursor.execute("SELECT user_type FROM users WHERE username = %s;", (username,))
        admin_user = cursor.fetchone()

        if not admin_user:
            raise HTTPException(status_code=401, detail="Admin user not found.")
        if admin_user["user_type"] != "admin":
            raise HTTPException(status_code=403, detail="Permission denied: Not an admin user.")
        # 3. 根据查询模式构建 SQL
        valid_modes = {
            "phone_number": "phone_number",
            "email": "email",
            "username": "username",
            "uid": "user_id"
        }

        if query_mode not in valid_modes:
            raise HTTPException(status_code=400, detail="Invalid query mode.")

        search_column = valid_modes[query_mode]

        # `uid` 应该是精确匹配，而不是模糊查询
        if query_mode == "uid":
            query = f"""
            SELECT user_id, username, points, phone_number, gender, email, user_type, created_at, updated_at
            FROM users
            WHERE {search_column} = %s
            """
            cursor.execute(query, (query_value,))
        else:
            # 其余模式使用 `LIKE` 进行模糊查询
            query = f"""
            SELECT user_id, username, points, phone_number, gender, email, user_type, created_at, updated_at
            FROM users
            WHERE {search_column} LIKE %s
            """
            search_value = f"%{query_value}%"  # 模糊匹配
            cursor.execute(query, (search_value,))

        users = cursor.fetchall()

        if not users:
            raise HTTPException(status_code=404, detail="User not found.")

        return users

    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error during query: {str(e)}")
    finally:
        cursor.close()
        connection.close()

def update_user_password(token: str, uid: int, new_password: str):
    """
    管理员修改用户密码：
    1. 验证 token 确保为管理员。
    2. 确认用户存在。
    3. 更新用户密码。
    """
    # 1. 验证 token
    try:
        payload = verify_token(token)  # 如果验证失败会抛出异常
        admin_username = payload["sub"]
    except ValueError as e:
        raise HTTPException(status_code=401, detail=str(e))

    # 2. 确认管理员权限
    connection = get_connection()
    if not connection:
        raise HTTPException(status_code=500, detail="Database connection failed!")

    try:
        cursor = connection.cursor(dictionary=True)
        cursor.execute("SELECT user_type FROM users WHERE username = %s;", (admin_username,))
        admin_user = cursor.fetchone()

        if not admin_user:
            raise HTTPException(status_code=401, detail="Admin user not found.")
        if admin_user["user_type"] != "admin":
            raise HTTPException(status_code=403, detail="Permission denied: Not an admin user.")

        # 3. 检查用户是否存在
        cursor.execute("SELECT * FROM users WHERE user_id = %s;", (uid,))
        user_to_update = cursor.fetchone()

        if not user_to_update:
            raise HTTPException(status_code=404, detail=f"User with ID {uid} not found.")

        # 4. 更新用户密码
        hashed_password = hashlib.md5(new_password.encode()).hexdigest()
        cursor.execute("UPDATE users SET password = %s WHERE user_id = %s;", (hashed_password, uid))
        connection.commit()

        return f"User with ID {uid} password updated successfully."

    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error during password update: {str(e)}")
    finally:
        cursor.close()
        connection.close()

# 在适当位置添加积分更新方法
def update_user_points(token: str, uid: int, points: int, reason: str):
    """更新用户积分"""
    # 1. 验证 token
    try:
        payload = verify_token(token)  # 如果验证失败会抛出异常
        admin_username = payload["sub"]
    except ValueError as e:
        raise HTTPException(status_code=401, detail=str(e))

    # 2. 确认管理员权限
    connection = get_connection()
    if not connection:
        raise HTTPException(status_code=500, detail="Database connection failed!")

    try:
        cursor = connection.cursor(dictionary=True)
        cursor.execute("SELECT user_type FROM users WHERE username = %s;", (admin_username,))
        admin_user = cursor.fetchone()

        if not admin_user:
            raise HTTPException(status_code=401, detail="Admin user not found.")
        if admin_user["user_type"] != "admin":
            raise HTTPException(status_code=403, detail="Permission denied: Not an admin user.")
        # 更新积分
        cursor.execute("UPDATE users SET points = points + %s WHERE user_id = %s",
                      (points, uid))
        # 记录积分变动历史
        cursor.execute(
            "INSERT INTO points_history (user_id, change_amount, reason) VALUES (%s, %s, %s)",
            (uid, points, reason)
        )
        connection.commit()
        return f"用户 {uid} 积分已更新"

    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error during password update: {str(e)}")
    finally:
        cursor.close()
        connection.close()