package mqtt

// MqttClient 定义了通用 MQTT 客户端接口
type MqttClient interface {
	// Publish 发布消息到指定 topic
	Publish(topic string, payload []byte) error
	// Subscribe 订阅指定 topic，接收回调
	Subscribe(topic string, handler func(topic string, payload []byte)) error
}

// 全局注册表
var clients = make(map[string]MqttClient)

// Register 注册一个 MQTT 客户端实现
func Register(name string, client MqttClient) {
	clients[name] = client
}

// GetClient 获取已注册的客户端
func GetClient(name string) (MqttClient, bool) {
	client, ok := clients[name]
	return client, ok
}