package micro

import (
	"context"
	"fmt"
	"git.nspix.com/golang/micro/gateway/rpc"
	"git.nspix.com/golang/micro/registry"
	"sync"
)

type Client struct {
	selector     *registry.Selector
	clientLocker sync.RWMutex
	clients      map[string]*rpc.Client
}

func (c *Client) Do(ctx context.Context, r *Request) (resp Response, err error) {
	var (
		ok     bool
		node   *registry.ServiceNode
		client *rpc.Client
	)
	c.clientLocker.RLock()
	client, ok = c.clients[r.ServiceName]
	c.clientLocker.RUnlock()
	if ok {
		goto _EXEC
	}
	if node, err = c.selector.Select(ctx, r.ServiceName); err != nil {
		return
	}
	client = rpc.NewClient()
	if err = client.Dialer("tcp", fmt.Sprintf("%s:%d", node.Address, node.Port)); err != nil {
		return
	}
_EXEC:
	return client.Do(ctx, rpc.NewRequest(r.Method, r.Body))
}

func (c *Client) Close() (err error) {
	c.clientLocker.Lock()
	defer c.clientLocker.Unlock()
	for name, client := range c.clients {
		_ = client.Close()
		delete(c.clients, name)
	}
	return
}

func NewClient(reg registry.Registry) *Client {
	return &Client{
		clients:  make(map[string]*rpc.Client),
		selector: registry.NewSelector(reg),
	}
}