package nnet

import (
	"encoding/json"
	"fmt"
	"git.noahlan.cn/noahlan/nnet"
	"git.noahlan.cn/noahlan/nnet/conn"
	"git.noahlan.cn/noahlan/nnet/event"
	"git.noahlan.cn/noahlan/nnet/packet"
	"git.noahlan.cn/noahlan/ntool/nlog"
)

type OnReadyFunc func()

func WithNNetClientEvents(onReady OnReadyFunc, packer packet.Packer) nnet.RunOption {
	return func(ngin *nnet.Engine) {
		ngin.EventManager().RegisterEventFront(event.EvtOnReceive, onReceiveEvent(ngin, onReady, packer))
	}
}

func onReceiveEvent(ngin *nnet.Engine, onReady OnReadyFunc, packer packet.Packer) event.OnReceiveFn {
	return func(nc *conn.Connection, p packet.IPacket) {
		pkg, ok := p.(*Packet)
		if !ok {
			nlog.Error(packet.ErrWrongPacketType)
			return
		}
		// Server to client
		switch pkg.PacketType {
		case Handshake:
			var handshakeData HandshakeResp
			err := json.Unmarshal(pkg.Data, &handshakeData)
			nlog.Must(err)

			hrd, _ := packer.Pack(Header{
				PacketType:    HandshakeAck,
				MessageHeader: MessageHeader{},
			}, nil)
			if err := nc.SendBytes(hrd); err != nil {
				return
			}
			nc.SetStatus(conn.StatusWorking)
			// onReady
			if onReady != nil {
				onReady()
			}
			if ngin.ShallLogDebug() {
				nlog.Debugf("connection handshake Id=%d, Remote=%s", nc.Session().ID(), nc.Conn().RemoteAddr())
			}
		case Kick:
			_ = nc.Close()
		case Data:
			status := nc.Status()
			if status != conn.StatusWorking {
				nlog.Errorf(fmt.Sprintf("receive data on socket which not yet ACK, session will be closed immediately, remote=%s",
					nc.Conn().RemoteAddr()))
				return
			}

			var lastMid uint64
			switch pkg.MsgType {
			case Response:
				lastMid = pkg.ID
			case Notify:
				lastMid = 0
			}
			nc.SetLastMID(lastMid)
		}
	}
}