package redis

import (
	"context"
	"fmt"
	"time"

	"github.com/redis/go-redis/v9"
)

const UserZSet = "chat:users"

type Client struct {
	rdb *redis.Client
}

// NewClient 创建 Redis 客户端
func NewClient(addr string, password string, db int) (*Client, error) {
	rdb := redis.NewClient(&redis.Options{
		Addr:     addr,
		Password: password,
		DB:       db,
	})

	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()

	if err := rdb.Ping(ctx).Err(); err != nil {
		return nil, fmt.Errorf("redis ping error: %w", err)
	}

	return &Client{rdb: rdb}, nil
}

// Close 关闭连接
func (c *Client) Close() error {
	return c.rdb.Close()
}

// AddUserToZSet 添加用户到 ZSet
func (c *Client) AddUserToZSet(key string, user string, score int64) error {
	return c.rdb.ZAdd(context.Background(), key, redis.Z{
		Score:  float64(score),
		Member: user,
	}).Err()
}

// RemoveUserFromZSet 从 ZSet 移除用户
func (c *Client) RemoveUserFromZSet(key string, user string) error {
	return c.rdb.ZRem(context.Background(), key, user).Err()
}

// CountUsers 获取在线用户数
func (c *Client) CountUsers(key string) (int64, error) {
	return c.rdb.ZCard(context.Background(), key).Result()
}