package broker

import (
	"context"
	"github.com/seaweedfs/seaweedfs/weed/pb/mq_pb"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
)

// FindTopicBrokers returns the brokers that are serving the topic
//
//  1. lock the topic
//
//  2. find the topic partitions on the filer
//     2.1 if the topic is not found, return error
//     2.2 if the request is_for_publish, create the topic
//     2.2.1 if the request is_for_subscribe, return error not found
//     2.2.2 if the request is_for_publish, create the topic
//     2.2 if the topic is found, return the brokers
//
//  3. unlock the topic
func (broker *MessageQueueBroker) LookupTopicBrokers(ctx context.Context, request *mq_pb.LookupTopicBrokersRequest) (resp *mq_pb.LookupTopicBrokersResponse, err error) {
	if broker.currentBalancer == "" {
		return nil, status.Errorf(codes.Unavailable, "no balancer")
	}
	if !broker.lockAsBalancer.IsLocked() {
		proxyErr := broker.withBrokerClient(false, broker.currentBalancer, func(client mq_pb.SeaweedMessagingClient) error {
			resp, err = client.LookupTopicBrokers(ctx, request)
			return nil
		})
		if proxyErr != nil {
			return nil, proxyErr
		}
		return resp, err
	}

	ret := &mq_pb.LookupTopicBrokersResponse{}
	ret.Topic = request.Topic
	ret.BrokerPartitionAssignments, err = broker.Balancer.LookupOrAllocateTopicPartitions(ret.Topic, request.IsForPublish, 6)
	return ret, err
}

// CheckTopicPartitionsStatus check the topic partitions on the broker
func (broker *MessageQueueBroker) CheckTopicPartitionsStatus(c context.Context, request *mq_pb.CheckTopicPartitionsStatusRequest) (*mq_pb.CheckTopicPartitionsStatusResponse, error) {
	ret := &mq_pb.CheckTopicPartitionsStatusResponse{}
	return ret, nil
}