package client

import (
	"fmt"
	"log"
	"net"
	"smpptester/pdu"
)

type SMPPClient struct {
	Id   int
	conn net.Conn
	port string
	log  log.Logger
}

func NewSMPPClient(port string, id int) *SMPPClient {
	client := &SMPPClient{
		Id:   id,
		port: port,
		log:  log.Logger{},
	}
	client.log = *log.New(log.Writer(), "", log.LstdFlags)
	client.log.SetPrefix(fmt.Sprintf("SMPP client %d: ", client.Id))
	return client
}

func (c *SMPPClient) Connect() error {
	conn, err := net.Dial("tcp", c.port)
	if err != nil {
		return fmt.Errorf("failed to connect to SMPP server: %w", err)
	}
	c.log.Printf("SMPP client %d connected to %s", c.Id, c.port)
	c.conn = conn
	return nil
}

func (c *SMPPClient) Close() {
	c.conn.Close()
	c.log.Printf("SMPP client %d closed connection", c.Id)
}

func (c *SMPPClient) Send(pdata pdu.PDU) error {
	if c.conn == nil {
		return fmt.Errorf("connection is not established")
	}

	pdata.UpdateSize()
	buf := pdu.ByteBufferPool.Get(pdata.Size())
	err := pdata.Encode(buf)
	if err != nil {
		return fmt.Errorf("failed to encode PDU: %w", err)
	}

	_, err = c.conn.Write(buf.Bytes())
	if err != nil {
		return fmt.Errorf("failed to send PDU: %w", err)
	}

	c.log.Printf("SMPP client %d sent PDU: %+v", c.Id, pdata)
	return nil
}