package cmppadapter

import (
	"bytes"
	"crypto/md5"
	"fmt"
	"log"
	"net"
	"testing"
	"time"

	cmpp "github.com/bigwhite/gocmpp"
	cmpputils "github.com/bigwhite/gocmpp/utils"
)

const (
	spikeUser     = "900001"
	spikePassword = "888888"
)

func TestGocmppConnectSubmitAndActiveTest(t *testing.T) {
	addr := reserveTCPAddr(t)
	handlers := []cmpp.Handler{
		cmpp.HandlerFunc(handleSpikeLogin),
		cmpp.HandlerFunc(handleSpikeSubmit),
	}

	go func() {
		err := cmpp.ListenAndServe(addr, cmpp.V30, 2*time.Second, 3, nil, handlers...)
		if err != nil {
			log.Printf("gocmpp spike server stopped: %v", err)
		}
	}()
	time.Sleep(300 * time.Millisecond)

	client := cmpp.NewClient(cmpp.V30)
	defer client.Disconnect()

	if err := client.Connect(addr, spikeUser, spikePassword, 2*time.Second); err != nil {
		t.Fatalf("connect gocmpp server: %v", err)
	}

	content, err := cmpputils.Utf8ToUcs2("测试gocmpp submit")
	if err != nil {
		t.Fatalf("encode submit content: %v", err)
	}

	_, err = client.SendReqPkt(&cmpp.Cmpp3SubmitReqPkt{
		PkTotal:            1,
		PkNumber:           1,
		RegisteredDelivery: 1,
		MsgLevel:           1,
		ServiceId:          "test",
		FeeUserType:        2,
		FeeTerminalId:      "13500002696",
		FeeTerminalType:    0,
		MsgFmt:             8,
		MsgSrc:             spikeUser,
		FeeType:            "02",
		FeeCode:            "10",
		ValidTime:          "151105131555101+",
		AtTime:             "",
		SrcId:              spikeUser,
		DestUsrTl:          1,
		DestTerminalId:     []string{"13500002696"},
		DestTerminalType:   0,
		MsgLength:          uint8(len(content)),
		MsgContent:         content,
	})
	if err != nil {
		t.Fatalf("send submit: %v", err)
	}

	submitRsp := recvUntil[*cmpp.Cmpp3SubmitRspPkt](t, client, 2*time.Second)
	if submitRsp.Result != 0 {
		t.Fatalf("unexpected submit result: %d", submitRsp.Result)
	}
	if submitRsp.MsgId == 0 {
		t.Fatal("expected gateway msg id")
	}

	_, err = client.SendReqPkt(&cmpp.CmppActiveTestReqPkt{})
	if err != nil {
		t.Fatalf("send active test: %v", err)
	}
	_ = recvUntil[*cmpp.CmppActiveTestRspPkt](t, client, 2*time.Second)
}

func TestGocmppDeliverReceiptPackAndUnpack(t *testing.T) {
	receipt := &cmpp.CmppReceiptPkt{
		MsgId:          12878564852733378560,
		Stat:           "DELIVRD",
		SubmitTime:     "2607010900",
		DoneTime:       "2607010901",
		DestTerminalId: "13500002696",
		SmscSequence:   42,
	}
	receiptBytes, err := receipt.Pack()
	if err != nil {
		t.Fatalf("pack receipt: %v", err)
	}

	deliver := &cmpp.Cmpp3DeliverReqPkt{
		MsgId:            12878564852733378560,
		DestId:           "106900000000",
		ServiceId:        "test",
		TpPid:            0,
		TpUdhi:           0,
		MsgFmt:           0,
		SrcTerminalId:    "13500002696",
		SrcTerminalType:  0,
		RegisterDelivery: 1,
		MsgLength:        uint8(cmpp.CmppReceiptPktLen),
		MsgContent:       string(receiptBytes),
	}

	data, err := deliver.Pack(1001)
	if err != nil {
		t.Fatalf("pack deliver receipt: %v", err)
	}

	var unpacked cmpp.Cmpp3DeliverReqPkt
	if err := unpacked.Unpack(data[8:]); err != nil {
		t.Fatalf("unpack deliver receipt: %v", err)
	}

	var gotReceipt cmpp.CmppReceiptPkt
	if err := gotReceipt.Unpack([]byte(unpacked.MsgContent)); err != nil {
		t.Fatalf("unpack receipt content: %v", err)
	}
	if gotReceipt.Stat != "DELIVRD" || gotReceipt.SmscSequence != 42 {
		t.Fatalf("unexpected receipt payload: %+v", &gotReceipt)
	}
}

func reserveTCPAddr(t *testing.T) string {
	t.Helper()

	listener, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatalf("reserve tcp addr: %v", err)
	}
	addr := listener.Addr().String()
	if err := listener.Close(); err != nil {
		t.Fatalf("close reserved listener: %v", err)
	}
	return addr
}

func recvUntil[T any](t *testing.T, client *cmpp.Client, timeout time.Duration) T {
	t.Helper()

	deadline := time.Now().Add(timeout)
	for time.Now().Before(deadline) {
		packet, err := client.RecvAndUnpackPkt(200 * time.Millisecond)
		if err != nil {
			continue
		}
		if typed, ok := packet.(T); ok {
			return typed
		}
	}

	var zero T
	t.Fatalf("timed out waiting for %T", zero)
	return zero
}

func handleSpikeLogin(response *cmpp.Response, packet *cmpp.Packet, logger *log.Logger) (bool, error) {
	req, ok := packet.Packer.(*cmpp.CmppConnReqPkt)
	if !ok {
		return true, nil
	}

	resp := response.Packer.(*cmpp.Cmpp3ConnRspPkt)
	resp.Version = 0x30

	if req.SrcAddr != cmpputils.OctetString(spikeUser, 6) {
		resp.Status = uint32(cmpp.ErrnoConnInvalidSrcAddr)
		return false, cmpp.ConnRspStatusErrMap[cmpp.ErrnoConnInvalidSrcAddr]
	}

	authSrc := md5.Sum(bytes.Join([][]byte{
		[]byte(cmpputils.OctetString(spikeUser, 6)),
		make([]byte, 9),
		[]byte(spikePassword),
		[]byte(cmpputils.TimeStamp2Str(req.Timestamp)),
	}, nil))

	if req.AuthSrc != string(authSrc[:]) {
		resp.Status = uint32(cmpp.ErrnoConnAuthFailed)
		return false, cmpp.ConnRspStatusErrMap[cmpp.ErrnoConnAuthFailed]
	}

	authIsmg := md5.Sum(bytes.Join([][]byte{{byte(resp.Status)}, authSrc[:], []byte(spikePassword)}, nil))
	resp.AuthIsmg = string(authIsmg[:])
	return false, nil
}

func handleSpikeSubmit(response *cmpp.Response, packet *cmpp.Packet, logger *log.Logger) (bool, error) {
	req, ok := packet.Packer.(*cmpp.Cmpp3SubmitReqPkt)
	if !ok {
		return true, nil
	}

	if req.DestUsrTl == 0 || len(req.DestTerminalId) == 0 {
		return false, fmt.Errorf("missing submit destination")
	}

	resp := response.Packer.(*cmpp.Cmpp3SubmitRspPkt)
	resp.MsgId = 12878564852733378560
	resp.Result = 0
	return false, nil
}