package generic

import (
	"context"
	"fmt"
	"google.golang.org/grpc"
	"sync"
)

type GrpcGenericClientFactory struct {
	scheme      string
	defaultOpts []grpc.DialOption
	clientCache *sync.Map
}

func NewGpcGenericClientFactory(scheme string, defaultOpts ...grpc.DialOption) *GrpcGenericClientFactory {
	return &GrpcGenericClientFactory{
		scheme:      scheme,
		defaultOpts: defaultOpts,
	}
}

func (f *GrpcGenericClientFactory) Init() {
	f.clientCache = &sync.Map{}
}

func (f *GrpcGenericClientFactory) NewClient(ctx context.Context, serviceName string, opts ...grpc.DialOption) (client *GrpcGenericClient, err error) {
	addr := fmt.Sprintf("%s:///%s", f.scheme, serviceName)
	dialOpts := make([]grpc.DialOption, 0, len(f.defaultOpts)+len(opts))
	dialOpts = append(dialOpts, f.defaultOpts...)
	dialOpts = append(dialOpts, opts...)
	conn, err := grpc.DialContext(ctx, addr, dialOpts...)
	if err != nil {
		return
	}
	client = NewGpcGenericClient(serviceName, conn)
	err = client.Init(ctx)
	return
}

func (f *GrpcGenericClientFactory) GetClient(ctx context.Context, serviceName string, opts ...grpc.DialOption) (client *GrpcGenericClient, err error) {
	val, ok := f.clientCache.Load(serviceName)
	if ok {
		client = val.(*GrpcGenericClient)
		return
	}
	client, err = f.NewClient(ctx, serviceName, opts...)
	if err != nil {
		return
	}
	f.clientCache.Store(serviceName, client)
	return
}