package notify

import (
	"b612.me/stario"
	"context"
	"errors"
	"math"
	"net"
	"testing"
	"time"
)

func TestServerStopClientSessionMarksStoppedAndCleansScopedState(t *testing.T) {
	server := NewServer().(*ServerCommon)
	stopCtx, stopFn := context.WithCancel(context.Background())
	defer stopFn()

	client, _, _ := newRegisteredServerClientForTest(t, server, "client-a", nil, stopCtx, stopFn)

	scope := serverFileScope(client)
	fileWait := server.getFileAckPool().prepare(scope, "file-1", "end", 0)
	signalWait := server.getSignalAckPool().prepare(scope, 1001)
	cache := server.getReceivedSignalCache()
	if seen := cache.seenOrRemember(scope, 1001); seen {
		t.Fatal("first seenOrRemember should report unseen signal")
	}

	server.stopClientSession(client, "manual stop", nil)

	if status := client.Status(); status.Alive || status.Reason != "manual stop" || status.Err != nil {
		t.Fatalf("unexpected client status after stop: %+v", status)
	}
	select {
	case <-client.StopMonitorChan():
	default:
		t.Fatal("client stop context should be closed")
	}
	if err := server.getFileAckPool().waitPrepared(fileWait, defaultFileAckTimeout); err == nil || err.Error() != "file ack canceled" {
		t.Fatalf("file waiter cancel mismatch: %v", err)
	}
	if err := server.getSignalAckPool().waitPrepared(signalWait, defaultSignalAckTimeout); err == nil || err.Error() != "signal ack canceled" {
		t.Fatalf("signal waiter cancel mismatch: %v", err)
	}
	if seen := cache.seenOrRemember(scope, 1001); seen {
		t.Fatal("received signal cache should be cleared for removed client scope")
	}
	if got := server.GetLogicalConn(client.ClientID); got != nil {
		t.Fatalf("logical should be removed from registry, got %+v", got)
	}
}

func TestServerStopLogicalSessionMarksStoppedAndCleansScopedState(t *testing.T) {
	server := NewServer().(*ServerCommon)
	stopCtx, stopFn := context.WithCancel(context.Background())
	defer stopFn()

	client, _, _ := newRegisteredServerClientForTest(t, server, "client-logical-stop", nil, stopCtx, stopFn)
	logical := client.LogicalConn()

	scope := serverFileScope(client)
	fileWait := server.getFileAckPool().prepare(scope, "file-logical-stop", "end", 0)
	signalWait := server.getSignalAckPool().prepare(scope, 1002)
	cache := server.getReceivedSignalCache()
	if seen := cache.seenOrRemember(scope, 1002); seen {
		t.Fatal("first seenOrRemember should report unseen signal")
	}

	server.stopLogicalSession(logical, "logical stop", nil)

	if status := client.Status(); status.Alive || status.Reason != "logical stop" || status.Err != nil {
		t.Fatalf("unexpected client status after logical stop: %+v", status)
	}
	select {
	case <-client.StopMonitorChan():
	default:
		t.Fatal("client stop context should be closed")
	}
	if err := server.getFileAckPool().waitPrepared(fileWait, defaultFileAckTimeout); err == nil || err.Error() != "file ack canceled" {
		t.Fatalf("file waiter cancel mismatch: %v", err)
	}
	if err := server.getSignalAckPool().waitPrepared(signalWait, defaultSignalAckTimeout); err == nil || err.Error() != "signal ack canceled" {
		t.Fatalf("signal waiter cancel mismatch: %v", err)
	}
	if seen := cache.seenOrRemember(scope, 1002); seen {
		t.Fatal("received signal cache should be cleared for removed logical scope")
	}
	if got := server.GetLogicalConn(client.ClientID); got != nil {
		t.Fatalf("logical should be removed from registry, got %+v", got)
	}
}

func TestServerStopClientSessionResetsScopedBulkWithServiceShutdown(t *testing.T) {
	server := NewServer().(*ServerCommon)
	stopCtx, stopFn := context.WithCancel(context.Background())
	defer stopFn()

	client, _, _ := newRegisteredServerClientForTest(t, server, "client-stop-bulk", nil, stopCtx, stopFn)
	scope := serverFileScope(client)
	bulk := newBulkHandle(context.Background(), server.getBulkRuntime(), scope, BulkOpenRequest{
		BulkID: "client-stop-bulk",
		DataID: 1,
		Range:  BulkRange{Length: 1},
	}, 0, client.LogicalConn(), nil, 0, nil, nil, nil, nil, nil)
	if err := server.getBulkRuntime().register(scope, bulk); err != nil {
		t.Fatalf("register bulk failed: %v", err)
	}

	server.stopClientSession(client, "manual stop", nil)

	if err := readBulkError(t, bulk, time.Second); !errors.Is(err, errServiceShutdown) {
		t.Fatalf("stopped client bulk error = %v, want %v", err, errServiceShutdown)
	}
	if _, ok := server.getBulkRuntime().lookup(scope, bulk.ID()); ok {
		t.Fatal("stopped client bulk should be removed from runtime")
	}
}

func TestServerStopLogicalSessionResetsScopedIOWithServiceShutdown(t *testing.T) {
	server := NewServer().(*ServerCommon)
	stopCtx, stopFn := context.WithCancel(context.Background())
	defer stopFn()

	logical, _, _ := newRegisteredServerLogicalForTest(t, server, "logical-stop-io", nil, stopCtx, stopFn)
	scope := serverFileScope(logical)
	stream := newStreamHandle(context.Background(), server.getStreamRuntime(), scope, StreamOpenRequest{
		StreamID: "logical-stop-stream",
		Channel:  StreamDataChannel,
	}, 0, logical, nil, 0, nil, nil, nil, defaultStreamConfig())
	if err := server.getStreamRuntime().register(scope, stream); err != nil {
		t.Fatalf("register stream failed: %v", err)
	}
	bulk := newBulkHandle(context.Background(), server.getBulkRuntime(), scope, BulkOpenRequest{
		BulkID: "logical-stop-bulk",
		DataID: 1,
		Range:  BulkRange{Length: 1},
	}, 0, logical, nil, 0, nil, nil, nil, nil, nil)
	if err := server.getBulkRuntime().register(scope, bulk); err != nil {
		t.Fatalf("register bulk failed: %v", err)
	}

	server.stopLogicalSession(logical, "logical stop", nil)

	if err := readStreamError(t, stream, time.Second); !errors.Is(err, errServiceShutdown) {
		t.Fatalf("stopped logical stream error = %v, want %v", err, errServiceShutdown)
	}
	if err := readBulkError(t, bulk, time.Second); !errors.Is(err, errServiceShutdown) {
		t.Fatalf("stopped logical bulk error = %v, want %v", err, errServiceShutdown)
	}
	if _, ok := server.getStreamRuntime().lookup(scope, stream.ID()); ok {
		t.Fatal("stopped logical stream should be removed from runtime")
	}
	if _, ok := server.getBulkRuntime().lookup(scope, bulk.ID()); ok {
		t.Fatal("stopped logical bulk should be removed from runtime")
	}
}

func TestServerStopClientSessionIsSafeToRepeat(t *testing.T) {
	server := NewServer().(*ServerCommon)
	stopCtx, stopFn := context.WithCancel(context.Background())
	defer stopFn()
	client, _, _ := newRegisteredServerClientForTest(t, server, "client-repeat", nil, stopCtx, stopFn)

	server.stopClientSession(client, "first stop", nil)
	server.stopClientSession(client, "second stop", nil)

	if status := client.Status(); status.Alive || status.Reason != "second stop" {
		t.Fatalf("unexpected repeated stop status: %+v", status)
	}
	if got := server.GetLogicalConn(client.ClientID); got != nil {
		t.Fatalf("logical should stay removed after repeated stop, got %+v", got)
	}
}

func TestServerBootstrapAcceptedLogicalRegistersStartedSession(t *testing.T) {
	server := NewServer().(*ServerCommon)
	UseLegacySecurityServer(server)
	server.maxReadTimeout = 2
	server.maxWriteTimeout = 3

	left, right := net.Pipe()
	defer left.Close()
	defer right.Close()

	logical := server.bootstrapAcceptedLogical("client-stream", nil, left)
	if logical == nil {
		t.Fatal("bootstrapAcceptedLogical should return logical")
	}
	if got := server.GetLogicalConn(logical.ClientID); got != logical {
		t.Fatal("bootstrapAcceptedLogical should register logical in registry")
	}
	client := clientConnFromLogical(logical)
	if !client.Status().Alive {
		t.Fatalf("client should start alive: %+v", client.Status())
	}
	if got := client.clientConnTransportSnapshot(); got != left {
		t.Fatal("client tuConn should match accepted stream conn")
	}
	if client.ClientAddr == nil || client.ClientAddr.String() != left.RemoteAddr().String() {
		t.Fatalf("client addr mismatch: got %v want %v", client.ClientAddr, left.RemoteAddr())
	}
	if client.clientConnStopContextSnapshot() == nil || client.clientConnStopFuncSnapshot() == nil {
		t.Fatal("client stop context should be initialized")
	}
	if got, want := client.clientConnMaxReadTimeoutSnapshot(), server.maxReadTimeout; got != want {
		t.Fatalf("maxReadTimeout mismatch: got %v want %v", got, want)
	}
	if got, want := client.clientConnMaxWriteTimeoutSnapshot(), server.maxWriteTimeout; got != want {
		t.Fatalf("maxWriteTimeout mismatch: got %v want %v", got, want)
	}
	if string(client.GetSecretKey()) != string(server.GetSecretKey()) {
		t.Fatal("client secret key should inherit server transport key")
	}
}

func TestServerBootstrapAcceptedLogicalSupportsPacketClient(t *testing.T) {
	server := NewServer().(*ServerCommon)

	addr, err := net.ResolveUDPAddr("udp", "127.0.0.1:12345")
	if err != nil {
		t.Fatalf("ResolveUDPAddr failed: %v", err)
	}

	logical := server.bootstrapAcceptedLogical("client-udp", addr, nil)
	if logical == nil {
		t.Fatal("bootstrapAcceptedLogical should return logical")
	}
	client := clientConnFromLogical(logical)
	if got := client.clientConnTransportSnapshot(); got != nil {
		t.Fatal("packet client should not keep stream conn")
	}
	if client.ClientAddr == nil || client.ClientAddr.String() != addr.String() {
		t.Fatalf("packet client addr mismatch: got %v want %v", client.ClientAddr, addr)
	}
	if got := server.GetLogicalConn(logical.ClientID); got != logical {
		t.Fatal("packet logical should be registered in registry")
	}
	if !client.Status().Alive {
		t.Fatalf("packet client should start alive: %+v", client.Status())
	}
}

func TestServerAttachAcceptedLogicalTransportRebindsExistingPeer(t *testing.T) {
	server := NewServer().(*ServerCommon)
	stopCtx, stopFn := context.WithCancel(context.Background())
	defer stopFn()
	queue := stario.NewQueueCtx(stopCtx, 4, math.MaxUint32)
	server.setServerSessionRuntime(&serverSessionRuntime{
		stopCtx: stopCtx,
		stopFn:  stopFn,
		queue:   queue,
	})

	oldLeft, oldRight := net.Pipe()
	defer oldRight.Close()
	logical := server.bootstrapAcceptedLogical("client-reattach", nil, oldLeft)
	if logical == nil {
		t.Fatal("bootstrapAcceptedLogical should return logical")
	}
	client := clientConnFromLogical(logical)

	newLeft, newRight := net.Pipe()
	defer newRight.Close()
	if err := server.attachAcceptedLogicalTransport(logical, newLeft.RemoteAddr(), newLeft); err != nil {
		t.Fatalf("attachAcceptedLogicalTransport failed: %v", err)
	}

	if got := server.GetLogicalConn(logical.ClientID); got != logical {
		t.Fatal("reattached logical should remain registered in registry")
	}
	if got := client.clientConnTransportSnapshot(); got != newLeft {
		t.Fatal("client transport snapshot should switch to new conn")
	}
	if client.ClientAddr == nil || client.ClientAddr.String() != newLeft.RemoteAddr().String() {
		t.Fatalf("client addr mismatch after attach: got %v want %v", client.ClientAddr, newLeft.RemoteAddr())
	}

	wire := queue.BuildMessage([]byte("reattached-peer"))
	if _, err := newRight.Write(wire); err != nil {
		t.Fatalf("new transport write failed: %v", err)
	}

	select {
	case msg := <-queue.RestoreChan():
		source := assertServerInboundQueueSource(t, msg.Conn, logical)
		if got, want := source.TransportGeneration, client.clientConnTransportGenerationSnapshot(); got != want {
			t.Fatalf("queue transport generation mismatch: got %d want %d", got, want)
		}
		if got, want := string(msg.Msg), "reattached-peer"; got != want {
			t.Fatalf("queue payload mismatch: got %q want %q", got, want)
		}
	case <-time.After(time.Second):
		t.Fatal("reattached peer did not push framed message")
	}
}

func TestServerUpsertAcceptedLogicalReusesExistingPeerByID(t *testing.T) {
	server := NewServer().(*ServerCommon)
	stopCtx, stopFn := context.WithCancel(context.Background())
	defer stopFn()
	queue := stario.NewQueueCtx(stopCtx, 4, math.MaxUint32)
	server.setServerSessionRuntime(&serverSessionRuntime{
		stopCtx: stopCtx,
		stopFn:  stopFn,
		queue:   queue,
	})

	oldLeft, oldRight := net.Pipe()
	defer oldRight.Close()
	initial, reused, err := server.upsertAcceptedLogical("client-upsert", nil, oldLeft)
	if err != nil {
		t.Fatalf("first upsertAcceptedLogical failed: %v", err)
	}
	if reused {
		t.Fatal("first upsertAcceptedLogical should create, not reuse")
	}

	newLeft, newRight := net.Pipe()
	defer newRight.Close()
	reattached, reused, err := server.upsertAcceptedLogical("client-upsert", newLeft.RemoteAddr(), newLeft)
	if err != nil {
		t.Fatalf("second upsertAcceptedLogical failed: %v", err)
	}
	if !reused {
		t.Fatal("second upsertAcceptedLogical should reuse existing peer")
	}
	if reattached != initial {
		t.Fatal("upsertAcceptedLogical should return the existing logical when ids match")
	}
	if got := server.GetLogicalConn("client-upsert"); got != initial {
		t.Fatal("logical registry should still point at reused peer")
	}

	wire := queue.BuildMessage([]byte("upsert-reused"))
	if _, err := newRight.Write(wire); err != nil {
		t.Fatalf("new transport write failed: %v", err)
	}

	select {
	case msg := <-queue.RestoreChan():
		source := assertServerInboundQueueSource(t, msg.Conn, initial)
		if got, want := source.TransportGeneration, initial.clientConnTransportGenerationSnapshot(); got != want {
			t.Fatalf("queue transport generation mismatch: got %d want %d", got, want)
		}
		if got, want := string(msg.Msg), "upsert-reused"; got != want {
			t.Fatalf("queue payload mismatch: got %q want %q", got, want)
		}
	case <-time.After(time.Second):
		t.Fatal("upsertAcceptedClient reused peer did not push framed message")
	}
}

func TestServerTransportScopedWaitsSwitchGenerationOnReattach(t *testing.T) {
	server := NewServer().(*ServerCommon)
	_, stopFn := context.WithCancel(context.Background())
	defer stopFn()

	firstLeft, firstRight := net.Pipe()
	defer firstRight.Close()
	logical := server.bootstrapAcceptedLogical("client-transport-scope", nil, firstLeft)
	if logical == nil {
		t.Fatal("bootstrapAcceptedLogical should return logical")
	}
	client := clientConnFromLogical(logical)
	client.markClientConnIdentityBound()

	scope1 := serverTransportScope(client)
	pending1 := server.getPendingWaitPool().createAndStoreWithScope(TransferMsg{ID: 8801, Type: MSG_SYNC_ASK}, scope1)
	fileWait1 := server.getFileAckPool().prepare(scope1, "file-transport-scope", "end", 0)
	signalWait1 := server.getSignalAckPool().prepare(scope1, 8802)

	server.detachClientSessionTransport(client, "read error", nil)

	select {
	case _, ok := <-pending1.Reply:
		if ok {
			t.Fatal("pending wait from detached generation should be canceled")
		}
	default:
		t.Fatal("pending wait from detached generation should close immediately")
	}
	if err := server.getFileAckPool().waitPrepared(fileWait1, defaultFileAckTimeout); err == nil || err.Error() != "file ack canceled" {
		t.Fatalf("file waiter from detached generation cancel mismatch: %v", err)
	}
	if err := server.getSignalAckPool().waitPrepared(signalWait1, defaultSignalAckTimeout); err == nil || err.Error() != "signal ack canceled" {
		t.Fatalf("signal waiter from detached generation cancel mismatch: %v", err)
	}

	secondLeft, secondRight := net.Pipe()
	defer secondRight.Close()
	if err := server.attachAcceptedLogicalTransport(logical, secondLeft.RemoteAddr(), secondLeft); err != nil {
		t.Fatalf("attachAcceptedLogicalTransport failed: %v", err)
	}

	scope2 := serverTransportScope(client)
	if scope2 == scope1 {
		t.Fatalf("transport scope should change after reattach: got %q", scope2)
	}

	pending2 := server.getPendingWaitPool().createAndStoreWithScope(TransferMsg{ID: 8803, Type: MSG_SYNC_ASK}, scope2)
	if server.getPendingWaitPool().deliverWithScopes(8803, []string{scope1}, Message{TransferMsg: TransferMsg{ID: 8803}}) {
		t.Fatal("stale generation pending reply should not match new scoped wait")
	}
	if !server.getPendingWaitPool().deliverWithScopes(8803, serverTransportDeliveryScopes(client), Message{TransferMsg: TransferMsg{ID: 8803}}) {
		t.Fatal("current generation pending reply should match scoped wait")
	}
	select {
	case _, ok := <-pending2.Reply:
		if !ok {
			t.Fatal("pending wait reply channel should remain open long enough to read reply")
		}
	case <-time.After(time.Second):
		t.Fatal("current generation pending wait should receive reply")
	}

	fileWait2 := server.getFileAckPool().prepare(scope2, "file-transport-scope", "end", 0)
	if server.getFileAckPool().deliver(scope1, FileEvent{Packet: FilePacket{FileID: "file-transport-scope", Stage: "end"}}) {
		t.Fatal("stale generation file ack should not match new scoped wait")
	}
	if !server.getFileAckPool().deliverAny(serverTransportDeliveryScopes(client), FileEvent{Packet: FilePacket{FileID: "file-transport-scope", Stage: "end"}}) {
		t.Fatal("current generation file ack should match scoped wait")
	}
	if err := server.getFileAckPool().waitPrepared(fileWait2, defaultFileAckTimeout); err != nil {
		t.Fatalf("current generation file waiter should succeed: %v", err)
	}

	signalWait2 := server.getSignalAckPool().prepare(scope2, 8804)
	if server.getSignalAckPool().deliver(scope1, 8804) {
		t.Fatal("stale generation signal ack should not match new scoped wait")
	}
	if !server.getSignalAckPool().deliverAny(serverTransportDeliveryScopes(client), 8804) {
		t.Fatal("current generation signal ack should match scoped wait")
	}
	if err := server.getSignalAckPool().waitPrepared(signalWait2, defaultSignalAckTimeout); err != nil {
		t.Fatalf("current generation signal waiter should succeed: %v", err)
	}
}