package srpc

import (
	"io"
	"net"
	"sync"
)

type RPCStatus uint8

const (
	RPCOK  RPCStatus = 0
	RPCERR RPCStatus = 1
)

type RPCRequest struct {
	FuncName string
	Payload  []byte
}

type RPCResponse struct {
	Status  RPCStatus
	Error   string
	Payload []byte
}

type IRPCConn interface {
	ReceiveRequest() (*RPCRequest, error)
	ReceiveResponse() (*RPCResponse, error)
	SendRequest(request *RPCRequest) error
	SendResponse(response *RPCResponse) error
	Close()
}

type TCPConn struct {
	conn net.Conn
	ed   IEncoderDecoder

	// interface
	IRPCConn
}

func (tc *TCPConn) ReceiveRequest() (ret *RPCRequest, err error) {
	ret = new(RPCRequest)

	dec := tc.ed.NewDecoder(tc.conn)
	if err = dec.Decode(ret); err != nil {
		return nil, err
	}

	return ret, err
}

func (tc *TCPConn) ReceiveResponse() (ret *RPCResponse, err error) {
	ret = new(RPCResponse)

	dec := tc.ed.NewDecoder(tc.conn)
	if err = dec.Decode(ret); err != nil {
		return nil, err
	}

	return ret, err
}

func (tc *TCPConn) SendRequest(request *RPCRequest) (err error) {
	enc := tc.ed.NewEncoder(tc.conn)
	err = enc.Encode(request)

	return err
}

func (tc *TCPConn) SendResponse(response *RPCResponse) (err error) {
	enc := tc.ed.NewEncoder(tc.conn)
	err = enc.Encode(response)

	return err
}

func (tc *TCPConn) Close() {
	tc.conn.Close()
}

func NewTCPConn(conn net.Conn, ed IEncoderDecoder) *TCPConn {
	ret := &TCPConn{}
	ret.conn = conn
	ret.ed = ed

	return ret
}

type NetHeartbeatConn struct {
	sync.Mutex
	conn io.ReadWriteCloser
	dec  IDecoder
	enc  IEncoder

	// interfaces
	IRPCConn
}

func (nhc *NetHeartbeatConn) ReceiveRequest() (ret *RPCRequest, err error) {
	nhc.Lock()
	defer nhc.Unlock()

	ret = new(RPCRequest)
	if err = nhc.dec.Decode(ret); err != nil {
		return nil, err
	}

	return ret, err
}

func (nhc *NetHeartbeatConn) ReceiveResponse() (ret *RPCResponse, err error) {
	nhc.Lock()
	defer nhc.Unlock()

	ret = new(RPCResponse)
	if err = nhc.dec.Decode(ret); err != nil {
		return nil, err
	}

	return ret, err
}

func (nhc *NetHeartbeatConn) SendRequest(request *RPCRequest) (err error) {
	nhc.Lock()
	defer nhc.Unlock()

	err = nhc.enc.Encode(request)
	return err
}

func (nhc *NetHeartbeatConn) SendResponse(response *RPCResponse) (err error) {
	nhc.Lock()
	defer nhc.Unlock()

	err = nhc.enc.Encode(response)
	return err
}

func (nhc *NetHeartbeatConn) Close() {
	nhc.Lock()
	defer nhc.Unlock()

	nhc.conn.Close()
}