CosmicClash/server/api/service_test.go

package api

import (
	"bufio"
	"bytes"
	"context"
	"encoding/binary"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"net"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"
	"time"

	"github.com/cosmic-clash/cosmic-clash/server/domain"
	"github.com/cosmic-clash/cosmic-clash/server/observability"
)

type queueBackendSpy struct{ createCalls, heartbeatCalls, cancelCalls, getCalls int }

func TestQueueResponseCarriesRecoveredMatchIdentity(t *testing.T) {
	response := toQueueResponse(domain.QueueTicket{TicketID: "ticket-1234567890", PlayerID: "player-1234567890", ProposalID: "proposal-1234567890", MatchID: "match-1234567890", State: domain.AssignmentReady})
	if response.ProposalID != "proposal-1234567890" {
		t.Fatalf("queue response proposal ID = %q", response.ProposalID)
	}
	if response.MatchID != "match-1234567890" {
		t.Fatalf("queue response match ID = %q", response.MatchID)
	}
}

type candidateIndexSpy struct {
	upsertCalls, removeCalls int
	upsertErr, removeErr     error
	last                     domain.Candidate
}

type probeRecorderSpy struct {
	calls int
	err   error
	last  struct {
		player, region string
		rtt            time.Duration
	}
}

type resultSubmitterSpy struct {
	calls  int
	err    error
	key    string
	result domain.MatchResult
}

type serverRegistrarSpy struct {
	calls           int
	binding         domain.WorkloadBinding
	protocol        int
	assignmentReady bool
	err             error
}

type serverShutdownerSpy struct {
	calls   int
	binding domain.WorkloadBinding
	reason  string
	key     string
	err     error
}

type serverConnectionSpy struct {
	connectCalls       int
	disconnectCalls    int
	binding            domain.WorkloadBinding
	playerID           string
	key                string
	expectedGeneration uint64
	generation         uint64
	err                error
}

func (s *serverConnectionSpy) ClaimPlayerConnection(_ context.Context, binding domain.WorkloadBinding, playerID string, expectedGeneration uint64, key string, _ time.Time) (uint64, error) {
	s.connectCalls++
	s.binding, s.playerID, s.expectedGeneration, s.key = binding, playerID, expectedGeneration, key
	return expectedGeneration + 1, s.err
}

func (s *serverConnectionSpy) RecordPlayerDisconnected(_ context.Context, binding domain.WorkloadBinding, playerID string, generation uint64, key string, _ time.Time) error {
	s.disconnectCalls++
	s.binding, s.playerID, s.generation, s.key = binding, playerID, generation, key
	return s.err
}

func (s *serverShutdownerSpy) ShutdownServer(_ context.Context, binding domain.WorkloadBinding, reason, key string, _ time.Time) error {
	s.calls++
	s.binding, s.reason, s.key = binding, reason, key
	return s.err
}

func (s *serverRegistrarSpy) RegisterServer(_ context.Context, binding domain.WorkloadBinding, protocol int, assignmentReady bool, _ string, _ time.Time) error {
	s.calls++
	s.binding, s.protocol, s.assignmentReady = binding, protocol, assignmentReady
	return s.err
}

type proposalPromoterSpy struct {
	calls    int
	proposal domain.Proposal
	err      error
}

func (p *proposalPromoterSpy) Promote(_ context.Context, proposal domain.Proposal, _ time.Time) error {
	p.calls++
	p.proposal = proposal
	return p.err
}

func (r *resultSubmitterSpy) SubmitResult(_ context.Context, key string, result domain.MatchResult, _ domain.WorkloadBinding, _ []byte, _ time.Time) error {
	r.calls++
	r.key, r.result = key, result
	return r.err
}

func (p *probeRecorderSpy) RecordProbe(_ context.Context, player, region string, rtt time.Duration, _ time.Time) error {
	p.calls++
	p.last.player, p.last.region, p.last.rtt = player, region, rtt
	return p.err
}

func (i *candidateIndexSpy) Upsert(_ context.Context, candidate domain.Candidate) error {
	i.upsertCalls++
	i.last = candidate
	return i.upsertErr
}

func (i *candidateIndexSpy) Remove(_ context.Context, _ domain.Playlist, _ string) error {
	i.removeCalls++
	return i.removeErr
}

type sessionBackendSpy struct{ calls int }

type proposalBackendSpy struct {
	proposal  domain.Proposal
	calls     int
	mutations int
}

func (b *proposalBackendSpy) Respond(_ context.Context, playerID, _ string, key string, accept bool, revision uint64, now time.Time) (domain.Proposal, error) {
	b.mutations++
	updated, err := b.proposal.Respond(playerID, key, accept, revision, now)
	if err == nil {
		b.proposal = updated
	}
	return updated, err
}

func (b *proposalBackendSpy) Get(_ context.Context, playerID, _ string, _ time.Time) (domain.Proposal, error) {
	b.calls++
	if !b.proposal.HasParticipant(playerID) {
		return domain.Proposal{}, domain.ErrNotParticipant
	}
	return b.proposal, nil
}

func (s *sessionBackendSpy) Authenticate(_ context.Context, sessionID, _ string, _ time.Time) (domain.Session, error) {
	s.calls++
	return domain.Session{SessionID: sessionID, PlayerID: "player-1"}, nil
}

type steamLoginSpy struct{ calls int }

func (s *steamLoginSpy) Authenticate(_ context.Context, ticket string, _ time.Time) (domain.VerifiedIdentity, error) {
	s.calls++
	if ticket != "valid-web-ticket" {
		return domain.VerifiedIdentity{}, domain.ErrTicketRejected
	}
	return domain.VerifiedIdentity{PlayerID: "player-1", SteamID: "steam-1"}, nil
}

func (b *queueBackendSpy) Create(_ context.Context, playerID, ticketID, _ string, spec domain.QueueSpec, now time.Time) (domain.QueueTicket, error) {
	b.createCalls++
	return domain.QueueTicket{TicketID: ticketID, PlayerID: playerID, Playlist: spec.Playlist, State: domain.Queued, EnqueuedAt: now, ExpiresAt: now.Add(domain.QueueExpiryWindow)}, nil
}
func (b *queueBackendSpy) Heartbeat(_ context.Context, playerID, ticketID, _ string, revision uint64, now time.Time) (domain.QueueTicket, error) {
	b.heartbeatCalls++
	return domain.QueueTicket{TicketID: ticketID, PlayerID: playerID, State: domain.Queued, Revision: revision + 1, EnqueuedAt: now, ExpiresAt: now.Add(domain.QueueExpiryWindow)}, nil
}
func (b *queueBackendSpy) Cancel(_ context.Context, playerID, ticketID, _ string, revision uint64, now time.Time) (domain.QueueTicket, error) {
	b.cancelCalls++
	return domain.QueueTicket{TicketID: ticketID, PlayerID: playerID, State: domain.Cancelled, Revision: revision + 1, EnqueuedAt: now, ExpiresAt: now}, nil
}
func (b *queueBackendSpy) Get(_ context.Context, playerID, ticketID string, now time.Time) (domain.QueueTicket, error) {
	b.getCalls++
	return domain.QueueTicket{TicketID: ticketID, PlayerID: playerID, State: domain.Queued, EnqueuedAt: now, ExpiresAt: now.Add(domain.QueueExpiryWindow)}, nil
}

func TestAuthenticatedQueueAPIUsesServerCandidateAndRevisionedMutations(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, err := sessions.Issue("player-1", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	queue := domain.NewQueue()
	service := &Service{Sessions: sessions, Queue: queue, Now: func() time.Time { return now }, Candidate: func(playerID, ticketID string) (domain.Candidate, error) {
		return domain.Candidate{PlayerID: playerID, TicketID: ticketID, EnqueuedAt: now, PredictedRTT: map[string]float64{"EU": 20}}, nil
	}}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	request := func(method, path, body string, headers map[string]string) *http.Response {
		req, _ := http.NewRequest(method, server.URL+path, strings.NewReader(body))
		for key, value := range headers {
			req.Header.Set(key, value)
		}
		response, requestErr := http.DefaultClient.Do(req)
		if requestErr != nil {
			t.Fatal(requestErr)
		}
		return response
	}
	headers := map[string]string{"Authorization": "Bearer " + session.SessionID + ":" + token, "Idempotency-Key": "create-key-123456"}
	response := request(http.MethodPost, "/v1/queue", `{"ticket_id":"ticket-1","playlist":"casual","client_build":"build-1","protocol_version":1}`, headers)
	if response.StatusCode != http.StatusCreated {
		t.Fatalf("create status = %d", response.StatusCode)
	}
	var created queueResponse
	if err := json.NewDecoder(response.Body).Decode(&created); err != nil {
		t.Fatal(err)
	}
	_ = response.Body.Close()
	if created.PlayerID != "player-1" || created.State != "QUEUED" || created.Revision != 0 {
		t.Fatalf("created = %+v", created)
	}
	response = request(http.MethodPost, "/v1/queue/ticket-1/heartbeat", `{}`, map[string]string{"Authorization": headers["Authorization"], "Idempotency-Key": "heartbeat-key-123456", "If-Match-Revision": "0"})
	if response.StatusCode != http.StatusOK {
		t.Fatalf("heartbeat status = %d", response.StatusCode)
	}
	_ = response.Body.Close()
	response = request(http.MethodPost, "/v1/queue/ticket-1/cancel", `{}`, map[string]string{"Authorization": headers["Authorization"], "Idempotency-Key": "cancel-key-123456", "If-Match-Revision": "0"})
	if response.StatusCode != http.StatusConflict {
		t.Fatalf("stale cancel status = %d", response.StatusCode)
	}
	_ = response.Body.Close()
}

func TestDocumentedContractRoutesAdaptToServiceAPI(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	backend := &queueBackendSpy{}
	service := &Service{
		SessionBackend: &sessionBackendSpy{},
		QueueBackend:   backend,
		Now:            func() time.Time { return now },
	}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	auth := "Bearer session-1:token-1"
	create, err := http.NewRequest(http.MethodPost, server.URL+"/api/v1/queue/tickets", strings.NewReader(`{"playlist":"casual","client_build":"build-1","protocol_version":1}`))
	if err != nil {
		t.Fatal(err)
	}
	create.Header.Set("Authorization", auth)
	create.Header.Set("Idempotency-Key", "contract-create-key-123456")
	response, err := http.DefaultClient.Do(create)
	if err != nil {
		t.Fatal(err)
	}
	if response.StatusCode != http.StatusCreated || backend.createCalls != 1 {
		t.Fatalf("create status = %d, calls = %d", response.StatusCode, backend.createCalls)
	}
	var ticket queueResponse
	if err := json.NewDecoder(response.Body).Decode(&ticket); err != nil {
		t.Fatal(err)
	}
	_ = response.Body.Close()
	if ticket.TicketID == "" {
		t.Fatal("contract adapter did not assign a ticket id")
	}
	heartbeat, err := http.NewRequest(http.MethodPost, server.URL+"/api/v1/queue/tickets/"+ticket.TicketID+"/heartbeat", nil)
	if err != nil {
		t.Fatal(err)
	}
	heartbeat.Header.Set("Authorization", auth)
	heartbeat.Header.Set("Idempotency-Key", "contract-heartbeat-key-123")
	heartbeat.Header.Set("If-Match-Revision", "0")
	response, err = http.DefaultClient.Do(heartbeat)
	if err != nil {
		t.Fatal(err)
	}
	_ = response.Body.Close()
	if response.StatusCode != http.StatusOK || backend.heartbeatCalls != 1 {
		t.Fatalf("heartbeat status = %d, calls = %d", response.StatusCode, backend.heartbeatCalls)
	}
	cancel, err := http.NewRequest(http.MethodDelete, server.URL+"/api/v1/queue/tickets/"+ticket.TicketID, nil)
	if err != nil {
		t.Fatal(err)
	}
	cancel.Header.Set("Authorization", auth)
	cancel.Header.Set("Idempotency-Key", "contract-cancel-key-123456")
	cancel.Header.Set("If-Match-Revision", "0")
	response, err = http.DefaultClient.Do(cancel)
	if err != nil {
		t.Fatal(err)
	}
	_ = response.Body.Close()
	if response.StatusCode != http.StatusNoContent || backend.cancelCalls != 1 {
		t.Fatalf("cancel status = %d, calls = %d", response.StatusCode, backend.cancelCalls)
	}
}

func TestDocumentedContractRoutesRejectNonOpaqueResourceIDs(t *testing.T) {
	service := &Service{}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	request, err := http.NewRequest(http.MethodPost, server.URL+"/api/v1/queue/tickets", strings.NewReader(`{"ticket_id":"short","playlist":"casual","client_build":"build-1","protocol_version":1}`))
	if err != nil {
		t.Fatal(err)
	}
	if response, requestErr := http.DefaultClient.Do(request); requestErr != nil {
		t.Fatal(requestErr)
	} else {
		if response.StatusCode != http.StatusBadRequest {
			t.Fatalf("short supplied ticket id status = %d, want 400", response.StatusCode)
		}
		response.Body.Close()
	}
	paths := []string{
		"/api/v1/queue/tickets/short/heartbeat",
		"/api/v1/proposals/proposal/unsafe/accept",
		"/api/v1/assignments/match/unsafe",
		"/api/v1/servers/server/unsafe/result",
	}
	for _, path := range paths {
		request, err := http.NewRequest(http.MethodGet, server.URL+path, nil)
		if err != nil {
			t.Fatal(err)
		}
		response, err := http.DefaultClient.Do(request)
		if err != nil {
			t.Fatal(err)
		}
		if response.StatusCode != http.StatusNotFound {
			t.Fatalf("%s status = %d, want 404", path, response.StatusCode)
		}
		response.Body.Close()
	}
}

func TestAuthenticatedWebSocketDeliversOnlyTargetedRevisionedEvents(t *testing.T) {
	service := &Service{SessionBackend: &sessionBackendSpy{}}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	invalid, err := http.NewRequest(http.MethodGet, server.URL+"/v1/events", nil)
	if err != nil {
		t.Fatal(err)
	}
	invalid.Header.Set("Upgrade", "websocket")
	invalid.Header.Set("Connection", "Upgrade")
	invalid.Header.Set("Sec-WebSocket-Key", "not-a-websocket-key")
	invalid.Header.Set("Authorization", "Bearer session-1:token-1")
	invalidResponse, err := server.Client().Do(invalid)
	if err != nil {
		t.Fatal(err)
	}
	_ = invalidResponse.Body.Close()
	if invalidResponse.StatusCode != http.StatusBadRequest {
		t.Fatalf("invalid handshake status = %d", invalidResponse.StatusCode)
	}
	connection, err := net.Dial("tcp", strings.TrimPrefix(server.URL, "http://"))
	if err != nil {
		t.Fatal(err)
	}
	defer connection.Close()
	_, err = io.WriteString(connection, "GET /v1/events HTTP/1.1\r\nHost: localhost\r\nUpgrade: websocket\r\nConnection: Upgrade\r\nSec-WebSocket-Version: 13\r\nSec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==\r\nAuthorization: Bearer session-1:token-1\r\n\r\n")
	if err != nil {
		t.Fatal(err)
	}
	reader := bufio.NewReader(connection)
	status, err := reader.ReadString('\n')
	if err != nil {
		t.Fatal(err)
	}
	if !strings.Contains(status, "101 Switching Protocols") {
		t.Fatalf("handshake status = %q", status)
	}
	for {
		line, err := reader.ReadString('\n')
		if err != nil {
			t.Fatal(err)
		}
		if line == "\r\n" {
			break
		}
	}
	time.Sleep(10 * time.Millisecond)
	if err := service.PublishControlPlaneEvent(ControlPlaneEvent{Event: "state_changed", Revision: 1, ResourceID: "ticket-1234567890123456", OccurredAt: time.Unix(1000, 0).UTC(), State: "QUEUED", PlayerID: "player-1"}); err != nil {
		t.Fatal(err)
	}
	if err := service.PublishControlPlaneEvent(ControlPlaneEvent{Event: "state_changed", Revision: 2, ResourceID: "ticket-1234567890123456", OccurredAt: time.Unix(1001, 0).UTC(), State: "PROPOSED", PlayerID: "player-2"}); err != nil {
		t.Fatal(err)
	}
	first, err := readServerWebSocketFrame(reader)
	if err != nil {
		t.Fatal(err)
	}
	var event ControlPlaneEvent
	if err := json.Unmarshal(first, &event); err != nil {
		t.Fatal(err)
	}
	if event.PlayerID != "" || event.Revision != 1 || event.ResourceID != "ticket-1234567890123456" || event.State != "QUEUED" {
		t.Fatalf("event = %+v", event)
	}
}

func TestServerRosterRequiresWorkloadBindingAndReturnsRawSignedEnvelopes(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	service := &Service{
		Now: func() time.Time { return now },
		WorkloadVerify: func(token string, at time.Time) (domain.WorkloadBinding, error) {
			if token != "workload-token" || !at.Equal(now) {
				t.Fatal("unexpected workload verification input")
			}
			return domain.WorkloadBinding{ServerID: "server-1", MatchID: "match-1", AllocationID: "allocation-1"}, nil
		},
		Roster: func(_ context.Context, binding domain.WorkloadBinding, at time.Time) ([][]byte, error) {
			if binding.ServerID != "server-1" || binding.MatchID != "match-1" || !at.Equal(now) {
				t.Fatal("unexpected roster binding")
			}
			return [][]byte{[]byte(`{"authorisation":{"player_id":"player-1","expires_at":"1970-01-01T00:33:20Z"},"signature":"sig"}`)}, nil
		},
	}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	request, _ := http.NewRequest(http.MethodGet, server.URL+"/v1/servers/server-1/roster", nil)
	request.Header.Set("Authorization", "Bearer workload-token")
	response, err := server.Client().Do(request)
	if err != nil {
		t.Fatal(err)
	}
	defer response.Body.Close()
	if response.StatusCode != http.StatusOK {
		t.Fatalf("roster status=%d", response.StatusCode)
	}
	var roster []json.RawMessage
	if err := json.NewDecoder(response.Body).Decode(&roster); err != nil {
		t.Fatal(err)
	}
	if len(roster) != 1 || !bytes.Contains(roster[0], []byte(`"player_id":"player-1"`)) {
		t.Fatalf("roster=%s", roster[0])
	}
}

func readServerWebSocketFrame(reader *bufio.Reader) ([]byte, error) {
	first, err := reader.ReadByte()
	if err != nil {
		return nil, err
	}
	second, err := reader.ReadByte()
	if err != nil {
		return nil, err
	}
	if first&0x0f != 0x1 || second&0x80 != 0 {
		return nil, errors.New("unexpected server websocket frame")
	}
	length := int(second & 0x7f)
	if length == 126 {
		var extended uint16
		if err := binary.Read(reader, binary.BigEndian, &extended); err != nil {
			return nil, err
		}
		length = int(extended)
	}
	payload := make([]byte, length)
	_, err = io.ReadFull(reader, payload)
	return payload, err
}

func TestEventHubClosesSlowSubscribersExactlyOnce(t *testing.T) {
	hub := newEventHub()
	subscriber := hub.subscribe("player-1")
	event := ControlPlaneEvent{Event: "state_changed", Revision: 1, ResourceID: "ticket-1234567890123456", OccurredAt: time.Unix(1000, 0).UTC(), State: "QUEUED", PlayerID: "player-1"}
	for i := 0; i < eventQueueCapacity; i++ {
		if err := hub.publish(event); err != nil {
			t.Fatal(err)
		}
	}
	if err := hub.publish(event); err != nil {
		t.Fatal(err)
	}
	for {
		_, open := <-subscriber.queue
		if !open {
			break
		}
	}
	hub.unsubscribe(subscriber)
}

func TestEventHubRejectsEventsOutsideTheV1Vocabulary(t *testing.T) {
	hub := newEventHub()
	base := ControlPlaneEvent{Revision: 1, ResourceID: "ticket-1234567890123456", OccurredAt: time.Unix(1000, 0).UTC(), PlayerID: "player-1"}
	invalid := []ControlPlaneEvent{
		{Event: "unknown", Revision: base.Revision, ResourceID: base.ResourceID, OccurredAt: base.OccurredAt, PlayerID: base.PlayerID},
		{Event: "state_changed", State: "QUEUED", Revision: base.Revision, ResourceID: "short", OccurredAt: base.OccurredAt, PlayerID: base.PlayerID},
		{Event: "state_changed", State: "QUEUED", Revision: base.Revision, ResourceID: "ticket-1234567890/unsafe", OccurredAt: base.OccurredAt, PlayerID: base.PlayerID},
		{Event: "state_changed", State: "NOT_A_STATE", Revision: base.Revision, ResourceID: base.ResourceID, OccurredAt: base.OccurredAt, PlayerID: base.PlayerID},
		{Event: "proposal_changed", State: "LIVE", Revision: base.Revision, ResourceID: base.ResourceID, OccurredAt: base.OccurredAt, PlayerID: base.PlayerID},
		{Event: "assignment_changed", Revision: base.Revision, ResourceID: base.ResourceID, OccurredAt: base.OccurredAt, PlayerID: base.PlayerID},
		{Event: "assignment_changed", MatchID: "match-1", ServerID: "server-1", Revision: base.Revision, ResourceID: base.ResourceID, OccurredAt: base.OccurredAt, PlayerID: base.PlayerID},
		{Event: "assignment_changed", MatchID: "match_1234567890", ServerID: "server/unsafe", Revision: base.Revision, ResourceID: base.ResourceID, OccurredAt: base.OccurredAt, PlayerID: base.PlayerID},
		{Event: "error", Code: "SECRET_LEAK", Revision: base.Revision, ResourceID: base.ResourceID, OccurredAt: base.OccurredAt, PlayerID: base.PlayerID},
	}
	for _, event := range invalid {
		if err := hub.publish(event); err == nil {
			t.Fatalf("invalid event was accepted: %+v", event)
		}
	}
}

func TestStateChangingAPIActionsPublishTargetedEvents(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	backend := &queueBackendSpy{}
	service := &Service{SessionBackend: &sessionBackendSpy{}, QueueBackend: backend, Now: func() time.Time { return now }, Proposals: make(map[string]*domain.Proposal)}
	subscriber := service.getEventHub().subscribe("player-1")
	defer service.getEventHub().unsubscribe(subscriber)

	create := httptest.NewRequest(http.MethodPost, "/v1/queue", strings.NewReader(`{"ticket_id":"ticket-1234567890123456","playlist":"casual","client_build":"build-1","protocol_version":1}`))
	create.Header.Set("Authorization", "Bearer session-1:token-1")
	create.Header.Set("Idempotency-Key", "create-event-key-123456")
	createRecorder := httptest.NewRecorder()
	service.queueCreate(createRecorder, create)
	if createRecorder.Code != http.StatusCreated {
		t.Fatalf("create status = %d", createRecorder.Code)
	}
	var queueEvent ControlPlaneEvent
	if err := json.Unmarshal(<-subscriber.queue, &queueEvent); err != nil {
		t.Fatal(err)
	}
	if queueEvent.Event != "state_changed" || queueEvent.ResourceID != "ticket-1234567890123456" || queueEvent.PlayerID != "" {
		t.Fatalf("queue event = %+v", queueEvent)
	}

	proposal, err := domain.NewProposal("proposal-1234567890123456", domain.Casual, []string{"player-1", "player-2"}, now)
	if err != nil {
		t.Fatal(err)
	}
	service.Proposals[proposal.ProposalID] = &proposal
	respond := httptest.NewRequest(http.MethodPost, "/v1/proposals/"+proposal.ProposalID+"/accept", nil)
	respond.Header.Set("Authorization", "Bearer session-1:token-1")
	respond.Header.Set("Idempotency-Key", "proposal-event-key-123456")
	respond.Header.Set("If-Match-Revision", "0")
	respondRecorder := httptest.NewRecorder()
	service.proposalMutation(respondRecorder, respond)
	if respondRecorder.Code != http.StatusOK {
		t.Fatalf("proposal status = %d", respondRecorder.Code)
	}
	var proposalEvent ControlPlaneEvent
	if err := json.Unmarshal(<-subscriber.queue, &proposalEvent); err != nil {
		t.Fatal(err)
	}
	if proposalEvent.Event != "proposal_changed" || proposalEvent.ResourceID != proposal.ProposalID || proposalEvent.State != "OPEN" {
		t.Fatalf("proposal event = %+v", proposalEvent)
	}
}

func TestFinalProposalAcceptancePromotesDurableMatchAndFailsRetryably(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	proposal, err := domain.NewProposal("proposal-promote-123456", domain.Casual, []string{"player-1", "player-2"}, now)
	if err != nil {
		t.Fatal(err)
	}
	backend := &proposalBackendSpy{proposal: proposal}
	promoter := &proposalPromoterSpy{}
	sessions := domain.NewSessionStore()
	session1, token1, err := sessions.Issue("player-1", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	session2, token2, err := sessions.Issue("player-2", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	service := &Service{Sessions: sessions, ProposalBackend: backend, ProposalPromoter: promoter, Now: func() time.Time { return now }}
	respond := func(credential, key, revision string) int {
		req := httptest.NewRequest(http.MethodPost, "/v1/proposals/"+proposal.ProposalID+"/accept", nil)
		req.Header.Set("Authorization", "Bearer "+credential)
		req.Header.Set("Idempotency-Key", key)
		req.Header.Set("If-Match-Revision", revision)
		recorder := httptest.NewRecorder()
		service.proposalMutation(recorder, req)
		return recorder.Code
	}
	credential1 := session1.SessionID + ":" + token1
	credential2 := session2.SessionID + ":" + token2
	if status := respond(credential1, "proposal-promote-first", "0"); status != http.StatusOK || promoter.calls != 0 {
		t.Fatalf("first acceptance status/calls = %d/%d", status, promoter.calls)
	}
	if status := respond(credential2, "proposal-promote-final", "1"); status != http.StatusOK || promoter.calls != 1 || promoter.proposal.State != domain.Accepted {
		t.Fatalf("final acceptance status/promoter = %d/%+v", status, promoter)
	}
	promoter.err = errors.New("database unavailable")
	// A duplicate response is replayed by the durable proposal backend and
	// retries promotion instead of asking the player to accept again.
	if status := respond(credential2, "proposal-promote-final", "1"); status != http.StatusServiceUnavailable || promoter.calls != 2 {
		t.Fatalf("promotion retry status/calls = %d/%d", status, promoter.calls)
	}
}

func TestProposalRecoveryUsesDurableBackendAndRemainsParticipantScoped(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	proposal, err := domain.NewProposal("proposal-1234567890123456", domain.Casual, []string{"player-1", "player-2"}, now)
	if err != nil {
		t.Fatal(err)
	}
	backend := &proposalBackendSpy{proposal: proposal}
	sessions := domain.NewSessionStore()
	participantSession, participantToken, err := sessions.Issue("player-1", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	outsiderSession, outsiderToken, err := sessions.Issue("outsider", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	service := &Service{Sessions: sessions, Proposals: map[string]*domain.Proposal{}, ProposalBackend: backend, Now: func() time.Time { return now }}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	get := func(session domain.Session, token string) int {
		request, err := http.NewRequest(http.MethodGet, server.URL+"/v1/proposals/"+proposal.ProposalID, nil)
		if err != nil {
			t.Fatal(err)
		}
		request.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
		response, err := server.Client().Do(request)
		if err != nil {
			t.Fatal(err)
		}
		_ = response.Body.Close()
		return response.StatusCode
	}
	if status := get(participantSession, participantToken); status != http.StatusOK {
		t.Fatalf("participant recovery status = %d", status)
	}
	respond, err := http.NewRequest(http.MethodPost, server.URL+"/v1/proposals/"+proposal.ProposalID+"/accept", nil)
	if err != nil {
		t.Fatal(err)
	}
	respond.Header.Set("Authorization", "Bearer "+participantSession.SessionID+":"+participantToken)
	respond.Header.Set("Idempotency-Key", "proposal-durable-response-123456")
	respond.Header.Set("If-Match-Revision", "0")
	response, err := server.Client().Do(respond)
	if err != nil {
		t.Fatal(err)
	}
	_ = response.Body.Close()
	if response.StatusCode != http.StatusOK || backend.mutations != 1 {
		t.Fatalf("durable response status = %d, mutations = %d", response.StatusCode, backend.mutations)
	}
	if status := get(outsiderSession, outsiderToken); status != http.StatusNotFound {
		t.Fatalf("outsider recovery status = %d", status)
	}
	if backend.calls != 2 {
		t.Fatalf("durable backend calls = %d", backend.calls)
	}
}

func TestQueueAPIRejectsUnauthenticatedUnknownAndOversizedInput(t *testing.T) {
	service := &Service{Sessions: domain.NewSessionStore(), Queue: domain.NewQueue(), Candidate: func(string, string) (domain.Candidate, error) { return domain.Candidate{}, nil }}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	request, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/queue", strings.NewReader(`{"ticket_id":"ticket-1","playlist":"casual","client_build":"build-1","protocol_version":1,"player_id":"attacker"}`))
	request.Header.Set("Idempotency-Key", "create-key-123456")
	response, err := http.DefaultClient.Do(request)
	if err != nil {
		t.Fatal(err)
	}
	if response.StatusCode != http.StatusUnauthorized {
		t.Fatalf("unauthenticated status = %d", response.StatusCode)
	}
	_ = response.Body.Close()
	sessionStore := domain.NewSessionStore()
	session, token, _ := sessionStore.Issue("player-1", time.Hour, time.Now())
	service.Sessions = sessionStore
	request, _ = http.NewRequest(http.MethodPost, server.URL+"/v1/queue", strings.NewReader(`{"ticket_id":"ticket-1","playlist":"casual","client_build":"build-1","protocol_version":1,"unknown":true}`))
	request.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
	request.Header.Set("Idempotency-Key", "create-key-123456")
	response, err = http.DefaultClient.Do(request)
	if err != nil {
		t.Fatal(err)
	}
	if response.StatusCode != http.StatusBadRequest {
		t.Fatalf("unknown field status = %d", response.StatusCode)
	}
	_ = response.Body.Close()
	request, _ = http.NewRequest(http.MethodPost, server.URL+"/v1/queue", strings.NewReader(`{"ticket_id":`))
	request.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
	request.Header.Set("Idempotency-Key", "create-key-654321")
	response, err = http.DefaultClient.Do(request)
	if err != nil {
		t.Fatal(err)
	}
	if response.StatusCode != http.StatusBadRequest {
		t.Fatalf("malformed body status = %d", response.StatusCode)
	}
	_ = response.Body.Close()
	request, _ = http.NewRequest(http.MethodPost, server.URL+"/v1/queue", strings.NewReader(`{"ticket_id":"ticket-1","playlist":"casual","client_build":"build-1","protocol_version":1}{"ticket_id":"ticket-2"}`))
	request.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
	request.Header.Set("Idempotency-Key", "create-key-789012")
	response, err = http.DefaultClient.Do(request)
	if err != nil {
		t.Fatal(err)
	}
	if response.StatusCode != http.StatusBadRequest {
		t.Fatalf("trailing JSON status = %d", response.StatusCode)
	}
	_ = response.Body.Close()
}

func TestQueueCreateRequiresCompatibilityMetadataAndPassesItToProvider(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, err := sessions.Issue("player-1", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	var got domain.QueueSpec
	service := &Service{
		Sessions: sessions,
		Queue:    domain.NewQueue(),
		Now:      func() time.Time { return now },
		CandidateV2: func(_ string, ticketID string, spec domain.QueueSpec) (domain.Candidate, error) {
			got = spec
			return domain.Candidate{PlayerID: "player-1", TicketID: ticketID, Playlist: spec.Playlist, ClientBuild: spec.ClientBuild, ProtocolVersion: spec.ProtocolVersion, EnqueuedAt: now}, nil
		},
	}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	request := func(body string) *http.Response {
		req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/queue", strings.NewReader(body))
		req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
		req.Header.Set("Idempotency-Key", "create-key-123456")
		response, requestErr := http.DefaultClient.Do(req)
		if requestErr != nil {
			t.Fatal(requestErr)
		}
		return response
	}
	response := request(`{"ticket_id":"ticket-1"}`)
	if response.StatusCode != http.StatusBadRequest {
		t.Fatalf("missing metadata status = %d", response.StatusCode)
	}
	_ = response.Body.Close()
	response = request(`{"ticket_id":"ticket-1","playlist":"invalid","client_build":"build-1","protocol_version":1}`)
	if response.StatusCode != http.StatusBadRequest {
		t.Fatalf("invalid playlist status = %d", response.StatusCode)
	}
	_ = response.Body.Close()
	response = request(`{"ticket_id":"ticket-1","playlist":"ranked","client_build":"build-1","protocol_version":7}`)
	if response.StatusCode != http.StatusCreated {
		t.Fatalf("valid metadata status = %d", response.StatusCode)
	}
	_ = response.Body.Close()
	if got.Playlist != domain.Ranked || got.ClientBuild != "build-1" || got.ProtocolVersion != 7 {
		t.Fatalf("provider received %+v", got)
	}
}

// TestQueueCreateEnforcesMinProtocolVersion covers the gap multiplayer-next.md
// 8.43 named "version-mismatch-specific client messaging": before this,
// queue_create accepted any protocol_version >= 1 unconditionally, so an
// outdated client below every other queued player's version would simply
// queue forever with no error at all -- the matcher's own compatibility
// check requires every formed player to share an identical protocol_version,
// so it could never be paired, and nothing ever told it why.
func TestQueueCreateEnforcesMinProtocolVersion(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, err := sessions.Issue("player-1", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	calls := 0
	service := &Service{
		Sessions:           sessions,
		Queue:              domain.NewQueue(),
		Now:                func() time.Time { return now },
		MinProtocolVersion: 5,
		CandidateV2: func(_ string, ticketID string, spec domain.QueueSpec) (domain.Candidate, error) {
			calls++
			return domain.Candidate{PlayerID: "player-1", TicketID: ticketID, Playlist: spec.Playlist, ClientBuild: spec.ClientBuild, ProtocolVersion: spec.ProtocolVersion, EnqueuedAt: now}, nil
		},
	}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	request := func(body string) (*http.Response, string) {
		req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/queue", strings.NewReader(body))
		req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
		req.Header.Set("Idempotency-Key", "create-key-123456")
		response, requestErr := http.DefaultClient.Do(req)
		if requestErr != nil {
			t.Fatal(requestErr)
		}
		decoded, _ := io.ReadAll(response.Body)
		response.Body.Close()
		return response, string(decoded)
	}
	response, body := request(`{"ticket_id":"ticket-1","playlist":"casual","client_build":"build-1","protocol_version":4}`)
	if response.StatusCode != http.StatusUpgradeRequired {
		t.Fatalf("below-floor status = %d, want 426 Upgrade Required; body=%s", response.StatusCode, body)
	}
	if !strings.Contains(body, "client_outdated") {
		t.Fatalf("below-floor body does not name the outdated-client error: %s", body)
	}
	if calls != 0 {
		t.Fatalf("candidate provider must not be reached for a rejected below-floor request, calls=%d", calls)
	}
	response, _ = request(`{"ticket_id":"ticket-1","playlist":"casual","client_build":"build-1","protocol_version":5}`)
	if response.StatusCode != http.StatusCreated {
		t.Fatalf("exactly-at-floor status = %d, want 201", response.StatusCode)
	}
	if calls != 1 {
		t.Fatalf("exactly-at-floor request should reach the provider once, calls=%d", calls)
	}
}

// TestQueueCreateMinProtocolVersionZeroIsDisabled proves the floor is opt-in:
// every existing Service literal across the codebase that never sets
// MinProtocolVersion must keep accepting protocol_version 1 exactly as
// before, unconditionally.
func TestQueueCreateMinProtocolVersionZeroIsDisabled(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, err := sessions.Issue("player-1", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	service := &Service{
		Sessions: sessions,
		Queue:    domain.NewQueue(),
		Now:      func() time.Time { return now },
		CandidateV2: func(_ string, ticketID string, spec domain.QueueSpec) (domain.Candidate, error) {
			return domain.Candidate{PlayerID: "player-1", TicketID: ticketID, Playlist: spec.Playlist, ClientBuild: spec.ClientBuild, ProtocolVersion: spec.ProtocolVersion, EnqueuedAt: now}, nil
		},
	}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/queue", strings.NewReader(`{"ticket_id":"ticket-1","playlist":"casual","client_build":"build-1","protocol_version":1}`))
	req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
	req.Header.Set("Idempotency-Key", "create-key-123456")
	response, err := http.DefaultClient.Do(req)
	if err != nil {
		t.Fatal(err)
	}
	defer response.Body.Close()
	if response.StatusCode != http.StatusCreated {
		t.Fatalf("status = %d, want 201 with MinProtocolVersion left at its zero default", response.StatusCode)
	}
}

func TestQueueCreateRejectsCandidateMetadataMismatch(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, _ := sessions.Issue("player-1", time.Hour, now)
	service := &Service{Sessions: sessions, Queue: domain.NewQueue(), Now: func() time.Time { return now }, CandidateV2: func(_ string, ticketID string, spec domain.QueueSpec) (domain.Candidate, error) {
		spec.ClientBuild = "tampered"
		return domain.Candidate{PlayerID: "player-1", TicketID: ticketID, Playlist: spec.Playlist, ClientBuild: spec.ClientBuild, ProtocolVersion: spec.ProtocolVersion, EnqueuedAt: now}, nil
	}}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/queue", strings.NewReader(`{"ticket_id":"ticket-1","playlist":"ranked","client_build":"build-1","protocol_version":1}`))
	req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
	req.Header.Set("Idempotency-Key", "create-key-123456")
	response, err := http.DefaultClient.Do(req)
	if err != nil {
		t.Fatal(err)
	}
	defer response.Body.Close()
	if response.StatusCode != http.StatusUnprocessableEntity {
		t.Fatalf("mismatch status = %d", response.StatusCode)
	}
}

func TestQueueCreateAPIRetriesIdenticallyAndRejectsKeyReuseWithChangedPayload(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, err := sessions.Issue("player-1", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	service := &Service{Sessions: sessions, Queue: domain.NewQueue(), Now: func() time.Time { return now }, Candidate: func(playerID, ticketID string) (domain.Candidate, error) {
		return domain.Candidate{PlayerID: playerID, TicketID: ticketID, EnqueuedAt: now}, nil
	}}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	request := func(body, key string) (int, queueResponse) {
		req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/queue", strings.NewReader(body))
		req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
		req.Header.Set("Idempotency-Key", key)
		response, requestErr := http.DefaultClient.Do(req)
		if requestErr != nil {
			t.Fatal(requestErr)
		}
		defer response.Body.Close()
		var decoded queueResponse
		if response.StatusCode == http.StatusCreated {
			if err := json.NewDecoder(response.Body).Decode(&decoded); err != nil {
				t.Fatal(err)
			}
		}
		return response.StatusCode, decoded
	}
	body := `{"ticket_id":"ticket-idempotent","playlist":"casual","client_build":"build-1","protocol_version":1}`
	status, first := request(body, "idempotency-key-123456")
	if status != http.StatusCreated {
		t.Fatalf("first create status=%d", status)
	}
	status, replay := request(body, "idempotency-key-123456")
	if status != http.StatusCreated || replay != first {
		t.Fatalf("identical replay status=%d first=%+v replay=%+v", status, first, replay)
	}
	changed := `{"ticket_id":"ticket-idempotent","playlist":"casual","client_build":"build-2","protocol_version":1}`
	status, _ = request(changed, "idempotency-key-123456")
	if status != http.StatusConflict {
		t.Fatalf("changed-payload replay status=%d, want conflict", status)
	}
}

func TestQueueAPIUsesInjectedPersistentBackendWithoutCandidateProvider(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, _ := sessions.Issue("player-1", time.Hour, now)
	backend := &queueBackendSpy{}
	service := &Service{Sessions: sessions, QueueBackend: backend, Now: func() time.Time { return now }}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/queue", strings.NewReader(`{"ticket_id":"ticket-1","playlist":"ranked","client_build":"build-1","protocol_version":1}`))
	req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
	req.Header.Set("Idempotency-Key", "create-key-123456")
	response, err := http.DefaultClient.Do(req)
	if err != nil {
		t.Fatal(err)
	}
	defer response.Body.Close()
	if response.StatusCode != http.StatusCreated || backend.createCalls != 1 {
		t.Fatalf("status=%d backend_calls=%d", response.StatusCode, backend.createCalls)
	}
}

func TestQueueAPIProjectsSuccessfulMutationsWithoutMakingRedisRequired(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, _ := sessions.Issue("player-1", time.Hour, now)
	backend := &queueBackendSpy{}
	index := &candidateIndexSpy{upsertErr: errors.New("redis unavailable"), removeErr: errors.New("redis unavailable")}
	service := &Service{Sessions: sessions, QueueBackend: backend, CandidateIndex: index, Now: func() time.Time { return now }}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	auth := "Bearer " + session.SessionID + ":" + token
	request := func(method, path, key, revision string) *http.Response {
		req, _ := http.NewRequest(method, server.URL+path, strings.NewReader(`{"ticket_id":"ticket-1","playlist":"ranked","client_build":"build-1","protocol_version":1}`))
		req.Header.Set("Authorization", auth)
		if key != "" {
			req.Header.Set("Idempotency-Key", key)
		}
		if revision != "" {
			req.Header.Set("If-Match-Revision", revision)
		}
		response, err := http.DefaultClient.Do(req)
		if err != nil {
			t.Fatal(err)
		}
		return response
	}
	response := request(http.MethodPost, "/v1/queue", "create-key-123456", "")
	if response.StatusCode != http.StatusCreated {
		t.Fatalf("create status=%d", response.StatusCode)
	}
	response.Body.Close()
	if index.upsertCalls != 1 {
		t.Fatalf("upsert calls=%d", index.upsertCalls)
	}
	response = request(http.MethodPost, "/v1/queue/ticket-1/cancel", "cancel-key-123456", "0")
	if response.StatusCode != http.StatusOK {
		t.Fatalf("cancel status=%d", response.StatusCode)
	}
	response.Body.Close()
	if index.removeCalls != 1 {
		t.Fatalf("remove calls=%d", index.removeCalls)
	}
}

func TestQueueAPIDelegatesAllMutationsAndRecoveryToBackend(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, _ := sessions.Issue("player-1", time.Hour, now)
	backend := &queueBackendSpy{}
	service := &Service{Sessions: sessions, QueueBackend: backend, Now: func() time.Time { return now }}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	auth := "Bearer " + session.SessionID + ":" + token
	request := func(method, path, body, key, revision string) *http.Response {
		req, _ := http.NewRequest(method, server.URL+path, strings.NewReader(body))
		req.Header.Set("Authorization", auth)
		if key != "" {
			req.Header.Set("Idempotency-Key", key)
		}
		if revision != "" {
			req.Header.Set("If-Match-Revision", revision)
		}
		response, err := http.DefaultClient.Do(req)
		if err != nil {
			t.Fatal(err)
		}
		return response
	}
	response := request(http.MethodGet, "/v1/queue/ticket-1", "", "", "")
	if response.StatusCode != http.StatusOK {
		t.Fatalf("get status = %d", response.StatusCode)
	}
	response.Body.Close()
	response = request(http.MethodPost, "/v1/queue/ticket-1/heartbeat", `{}`, "heartbeat-key-123456", "0")
	if response.StatusCode != http.StatusOK {
		t.Fatalf("heartbeat status = %d", response.StatusCode)
	}
	response.Body.Close()
	response = request(http.MethodPost, "/v1/queue/ticket-1/cancel", `{}`, "cancel-key-123456", "1")
	if response.StatusCode != http.StatusOK {
		t.Fatalf("cancel status = %d", response.StatusCode)
	}
	response.Body.Close()
	if backend.getCalls != 1 || backend.heartbeatCalls != 1 || backend.cancelCalls != 1 {
		t.Fatalf("backend calls = %+v", backend)
	}
}

func TestQueueAPIUsesInjectedSessionBackend(t *testing.T) {
	backend := &sessionBackendSpy{}
	queue := &queueBackendSpy{}
	service := &Service{SessionBackend: backend, QueueBackend: queue, Now: func() time.Time { return time.Unix(1000, 0).UTC() }}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	req, _ := http.NewRequest(http.MethodGet, server.URL+"/v1/queue/ticket-1", nil)
	req.Header.Set("Authorization", "Bearer durable-session:durable-token")
	response, err := http.DefaultClient.Do(req)
	if err != nil {
		t.Fatal(err)
	}
	defer response.Body.Close()
	if response.StatusCode != http.StatusOK || backend.calls != 1 || queue.getCalls != 1 {
		t.Fatalf("status=%d session_calls=%d queue_calls=%d", response.StatusCode, backend.calls, queue.getCalls)
	}
}

func TestSteamSessionAPIRequiresBackendVerificationAndIssuesOpaqueSession(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	provider := &steamLoginSpy{}
	service := &Service{Sessions: sessions, SteamLogin: provider, Now: func() time.Time { return now }}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	request := func(body string) *http.Response {
		req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/session/steam", strings.NewReader(body))
		response, err := http.DefaultClient.Do(req)
		if err != nil {
			t.Fatal(err)
		}
		return response
	}
	response := request(`{"web_api_ticket":"valid-web-ticket","steam_id":"spoofed"}`)
	if response.StatusCode != http.StatusBadRequest {
		t.Fatalf("extra field status = %d", response.StatusCode)
	}
	response.Body.Close()
	response = request(`{"web_api_ticket":"invalid"}`)
	if response.StatusCode != http.StatusUnauthorized {
		t.Fatalf("invalid ticket status = %d", response.StatusCode)
	}
	response.Body.Close()
	response = request(`{"web_api_ticket":"valid-web-ticket"}`)
	if response.StatusCode != http.StatusOK {
		t.Fatalf("valid ticket status = %d", response.StatusCode)
	}
	var result struct {
		PlayerID    string `json:"player_id"`
		AccessToken string `json:"access_token"`
	}
	if err := json.NewDecoder(response.Body).Decode(&result); err != nil {
		t.Fatal(err)
	}
	response.Body.Close()
	if result.PlayerID != "player-1" || !strings.Contains(result.AccessToken, ":") || provider.calls != 2 {
		t.Fatalf("session result=%+v provider_calls=%d", result, provider.calls)
	}
}

func TestQueueRecoveryAPIIsAuthenticatedOwnerOnlyAndExpiresStaleTickets(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	ownerSession, ownerToken, err := sessions.Issue("player-1", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	otherSession, otherToken, err := sessions.Issue("player-2", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	queue := domain.NewQueue()
	service := &Service{Sessions: sessions, Queue: queue, Now: func() time.Time { return now }, Candidate: func(playerID, ticketID string) (domain.Candidate, error) {
		return domain.Candidate{PlayerID: playerID, TicketID: ticketID, EnqueuedAt: now}, nil
	}}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	create, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/queue", strings.NewReader(`{"ticket_id":"ticket-recovery-123456","playlist":"casual","client_build":"build-1","protocol_version":1}`))
	create.Header.Set("Authorization", "Bearer "+ownerSession.SessionID+":"+ownerToken)
	create.Header.Set("Idempotency-Key", "queue-create-recovery-123456")
	response, err := http.DefaultClient.Do(create)
	if err != nil || response.StatusCode != http.StatusCreated {
		t.Fatalf("create status=%v err=%v", response.StatusCode, err)
	}
	_ = response.Body.Close()
	get, _ := http.NewRequest(http.MethodGet, server.URL+"/v1/queue/ticket-recovery-123456", nil)
	get.Header.Set("Authorization", "Bearer "+ownerSession.SessionID+":"+ownerToken)
	response, err = http.DefaultClient.Do(get)
	if err != nil || response.StatusCode != http.StatusOK {
		t.Fatalf("owner recovery status=%v err=%v", response.StatusCode, err)
	}
	_ = response.Body.Close()
	get.Header.Set("Authorization", "Bearer "+otherSession.SessionID+":"+otherToken)
	response, err = http.DefaultClient.Do(get)
	if err != nil || response.StatusCode != http.StatusForbidden {
		t.Fatalf("cross-player recovery status=%v err=%v", response.StatusCode, err)
	}
	_ = response.Body.Close()
	service.Now = func() time.Time { return now.Add(domain.QueueExpiryWindow) }
	get.Header.Set("Authorization", "Bearer "+ownerSession.SessionID+":"+ownerToken)
	response, err = http.DefaultClient.Do(get)
	if err != nil || response.StatusCode != http.StatusGone {
		t.Fatalf("expired recovery status=%v err=%v", response.StatusCode, err)
	}
	_ = response.Body.Close()
}

func TestReadOnlyAPIsEmitLifecycleEvents(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, err := sessions.Issue("player-a", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	queue := domain.NewQueue()
	if _, err := queue.Create("player-a", "ticket-read-123456", "create-read-123456", domain.Candidate{PlayerID: "player-a", TicketID: "ticket-read-123456", Playlist: domain.Casual, EnqueuedAt: now}, now); err != nil {
		t.Fatal(err)
	}
	proposal, err := domain.NewProposal("proposal-read-123456", domain.Casual, []string{"player-a", "player-b"}, now)
	if err != nil {
		t.Fatal(err)
	}
	events := make([]observability.Event, 0)
	service := &Service{
		Sessions: sessions, Queue: queue, Proposals: map[string]*domain.Proposal{proposal.ProposalID: &proposal},
		RankedProfiles: map[string]domain.RankedProfile{"player-a": {Rating: domain.Rating{Value: 1500, RD: 100, Volatility: 0.06}}},
		TierPolicy:     domain.DefaultTierPolicy(), Now: func() time.Time { return now },
		Assignment: func(_ context.Context, playerID, matchID string, _ time.Time) (AssignmentView, error) {
			return AssignmentView{MatchID: matchID, PlayerID: playerID, ServerID: "server-read", Slot: 0, ProtocolVersion: 1, Transport: "enet", Endpoint: "127.0.0.1:30001", JoinAuthorisation: "join-token", ExpiresAt: now.Add(time.Minute)}, nil
		},
		Log: func(event observability.Event) { events = append(events, event) },
	}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	auth := "Bearer " + session.SessionID + ":" + token
	for _, path := range []string{"/v1/queue/ticket-read-123456", "/v1/proposals/proposal-read-123456", "/v1/assignments/match-read-123456", "/api/v1/profile", "/v1/profile/ranked"} {
		req, _ := http.NewRequest(http.MethodGet, server.URL+path, nil)
		req.Header.Set("Authorization", auth)
		response, requestErr := http.DefaultClient.Do(req)
		if requestErr != nil {
			t.Fatal(requestErr)
		}
		if response.StatusCode != http.StatusOK {
			t.Fatalf("GET %s status = %d", path, response.StatusCode)
		}
		response.Body.Close()
	}
	seen := map[string]bool{}
	for _, event := range events {
		seen[event.Event] = true
	}
	for _, eventName := range []string{"queue_get", "proposal_get", "assignment_get", "profile_get", "ranked_profile_get"} {
		if !seen[eventName] {
			t.Fatalf("read event %q missing from %+v", eventName, events)
		}
	}
}

func TestAuthenticatedProposalAPIUsesRevisionAndIdempotencyPolicy(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, err := sessions.Issue("player-a", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	proposal, err := domain.NewProposal("proposal-123456789", domain.Casual, []string{"player-a", "player-b"}, now)
	if err != nil {
		t.Fatal(err)
	}
	service := &Service{Sessions: sessions, Proposals: map[string]*domain.Proposal{proposal.ProposalID: &proposal}, Now: func() time.Time { return now }}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/proposals/"+proposal.ProposalID+"/accept", nil)
	req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
	req.Header.Set("Idempotency-Key", "proposal-response-123456")
	req.Header.Set("If-Match-Revision", "0")
	response, err := http.DefaultClient.Do(req)
	if err != nil {
		t.Fatal(err)
	}
	if response.StatusCode != http.StatusOK {
		t.Fatalf("proposal accept status = %d", response.StatusCode)
	}
	_ = response.Body.Close()
	req, _ = http.NewRequest(http.MethodPost, server.URL+"/v1/proposals/"+proposal.ProposalID+"/accept", nil)
	req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
	req.Header.Set("Idempotency-Key", "proposal-response-654321")
	req.Header.Set("If-Match-Revision", "0")
	response, err = http.DefaultClient.Do(req)
	if err != nil {
		t.Fatal(err)
	}
	if response.StatusCode != http.StatusConflict {
		t.Fatalf("stale proposal response status = %d", response.StatusCode)
	}
	_ = response.Body.Close()
}

func TestRankedProfileAPIReturnsBackendTierAndHidesCasualData(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, err := sessions.Issue("player-a", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	policy, err := domain.NewTierPolicy([]domain.TierBand{{Tier: domain.RankTierBronze, MinRating: 0}, {Tier: domain.RankTierGold, MinRating: 1500}})
	if err != nil {
		t.Fatal(err)
	}
	service := &Service{
		Sessions:       sessions,
		RankedProfiles: map[string]domain.RankedProfile{"player-a": {Rating: domain.Rating{Value: 1600, RD: 200, Volatility: 0.06}, RankedGames: 10, CurrentSeasonID: "season-current", CurrentSeasonEndsAt: now.Add(48 * time.Hour), LastSeasonID: "season-1"}},
		TierPolicy:     policy,
		Now:            func() time.Time { return now },
	}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	req, _ := http.NewRequest(http.MethodGet, server.URL+"/v1/profile/ranked", nil)
	req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
	response, err := http.DefaultClient.Do(req)
	if err != nil {
		t.Fatal(err)
	}
	defer response.Body.Close()
	if response.StatusCode != http.StatusOK {
		t.Fatalf("ranked profile status = %d", response.StatusCode)
	}
	var body rankedProfileResponse
	if err := json.NewDecoder(response.Body).Decode(&body); err != nil {
		t.Fatal(err)
	}
	if body.Tier != string(domain.RankTierGold) || body.Provisional || body.RankedGames != 10 || body.SeasonID != "season-current" || body.SeasonEndsAt != "1970-01-03T00:16:40Z" {
		t.Fatalf("ranked profile response = %+v", body)
	}
}

func TestServerResultAPIRequiresBoundWorkloadAndDelegatesDurableSubmission(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	binding := domain.WorkloadBinding{MatchID: "match-1", ServerID: "server-1"}
	submitter := &resultSubmitterSpy{}
	service := &Service{Now: func() time.Time { return now }, WorkloadVerify: func(token string, at time.Time) (domain.WorkloadBinding, error) {
		if token != "workload-token" || !at.Equal(now) {
			t.Fatalf("verifier input=%q %v", token, at)
		}
		return binding, nil
	}, ResultSubmitter: submitter}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	body := `{"match_id":"match-1","result_nonce":"nonce-1234567890","score":{"team_0":3,"team_1":2},"integrity_state":"CERTIFIED"}`
	req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/servers/server-1/result", strings.NewReader(body))
	req.Header.Set("Authorization", "Bearer workload-token")
	req.Header.Set("Idempotency-Key", "result-key-123456")
	response, err := http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusAccepted {
		t.Fatalf("status=%v err=%v", response.StatusCode, err)
	}
	response.Body.Close()
	if submitter.calls != 1 || submitter.key != "result-key-123456" || submitter.result.Team0Score != 3 {
		t.Fatalf("submission=%+v calls=%d", submitter, submitter.calls)
	}
	req, _ = http.NewRequest(http.MethodPost, server.URL+"/v1/servers/server-2/result", strings.NewReader(body))
	req.Header.Set("Authorization", "Bearer workload-token")
	req.Header.Set("Idempotency-Key", "result-key-123456")
	response, err = http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusUnauthorized {
		t.Fatalf("wrong server status=%v err=%v", response.StatusCode, err)
	}
	response.Body.Close()
}

func TestContractServerRoutesAdaptTwoSegmentPaths(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	binding := domain.WorkloadBinding{AllocationID: "allocation-1", MatchID: "match_1234567890", ServerID: "server_123456789"}
	submitter := &resultSubmitterSpy{}
	registrar := &serverRegistrarSpy{}
	service := &Service{Now: func() time.Time { return now }, WorkloadVerify: func(token string, _ time.Time) (domain.WorkloadBinding, error) {
		if token != "workload-token" {
			return domain.WorkloadBinding{}, errors.New("bad token")
		}
		return binding, nil
	}, ResultSubmitter: submitter, ServerRegistrar: registrar}
	server := httptest.NewServer(service.Handler())
	defer server.Close()

	registerBody := `{"match_id":"match_1234567890","protocol_version":1,"image_digest":"sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa","assignment_ready":false}`
	req, _ := http.NewRequest(http.MethodPost, server.URL+"/api/v1/servers/server_123456789/register", strings.NewReader(registerBody))
	req.Header.Set("Authorization", "Bearer workload-token")
	req.Header.Set("Idempotency-Key", "contract-register-key-1")
	response, err := http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusNoContent || registrar.calls != 1 {
		t.Fatalf("register status=%v err=%v calls=%d", response.StatusCode, err, registrar.calls)
	}
	response.Body.Close()

	resultBody := `{"match_id":"match_1234567890","result_nonce":"nonce-1234567890","score":{"team_0":3,"team_1":2},"integrity_state":"CERTIFIED"}`
	req, _ = http.NewRequest(http.MethodPost, server.URL+"/api/v1/servers/server_123456789/result", strings.NewReader(resultBody))
	req.Header.Set("Authorization", "Bearer workload-token")
	req.Header.Set("Idempotency-Key", "contract-result-key-123")
	response, err = http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusAccepted || submitter.calls != 1 {
		t.Fatalf("result status=%v err=%v calls=%d", response.StatusCode, err, submitter.calls)
	}
	response.Body.Close()
}

// TestServerMutationLoggingNeverLeaksRequestSecrets is a secret canary: it
// drives the register and result routes end to end with realistic-looking
// bearer tokens and a result nonce, captures every event actually emitted
// through Service.Log during those real requests, and asserts the literal
// secret values never appear anywhere in the encoded output -- not just that
// observability.redact() strips a synthetic value under a known key name (see
// TestEncodeCorrelatesStagesAndRedactsNestedCredentials in the observability
// package for that narrower unit test).
func TestServerMutationLoggingNeverLeaksRequestSecrets(t *testing.T) {
	const bearerToken = "wl-canary-secret-do-not-log-9f8e7d6c5b4a"
	const resultNonce = "nonce-canary-secret-value-1a2b3c4d5e6f"
	now := time.Unix(1000, 0).UTC()
	binding := domain.WorkloadBinding{AllocationID: "allocation-1", MatchID: "match-1", ServerID: "server-1"}
	registrar := &serverRegistrarSpy{}
	submitter := &resultSubmitterSpy{}
	var captured [][]byte
	service := &Service{
		Now: func() time.Time { return now },
		WorkloadVerify: func(token string, _ time.Time) (domain.WorkloadBinding, error) {
			if token != bearerToken {
				return domain.WorkloadBinding{}, errors.New("bad token")
			}
			return binding, nil
		},
		ServerRegistrar: registrar,
		ResultSubmitter: submitter,
		Log: func(event observability.Event) {
			payload, err := observability.Encode(event)
			if err != nil {
				t.Fatalf("encode event: %v", err)
			}
			captured = append(captured, payload)
		},
	}
	server := httptest.NewServer(service.Handler())
	defer server.Close()

	registerBody := `{"match_id":"match-1","protocol_version":1,"image_digest":"sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa","assignment_ready":true}`
	req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/servers/server-1/register", strings.NewReader(registerBody))
	req.Header.Set("Authorization", "Bearer "+bearerToken)
	req.Header.Set("Idempotency-Key", "canary-register-key-1")
	response, err := http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusNoContent {
		t.Fatalf("register status=%v err=%v", response.StatusCode, err)
	}
	response.Body.Close()

	resultBody := fmt.Sprintf(`{"match_id":"match-1","result_nonce":%q,"score":{"team_0":3,"team_1":2},"integrity_state":"CERTIFIED"}`, resultNonce)
	req, _ = http.NewRequest(http.MethodPost, server.URL+"/v1/servers/server-1/result", strings.NewReader(resultBody))
	req.Header.Set("Authorization", "Bearer "+bearerToken)
	req.Header.Set("Idempotency-Key", "canary-result-key-1234")
	response, err = http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusAccepted {
		t.Fatalf("result status=%v err=%v", response.StatusCode, err)
	}
	response.Body.Close()

	// An unauthorized attempt must also log nothing sensitive -- it's the one
	// call site handling a token that never even verified successfully.
	req, _ = http.NewRequest(http.MethodPost, server.URL+"/v1/servers/server-1/register", strings.NewReader(registerBody))
	req.Header.Set("Authorization", "Bearer wrong-"+bearerToken)
	req.Header.Set("Idempotency-Key", "canary-register-key-2")
	response, err = http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusUnauthorized {
		t.Fatalf("unauthorized register status=%v err=%v", response.StatusCode, err)
	}
	response.Body.Close()

	if len(captured) == 0 {
		t.Fatal("no events were logged; the canary can't prove anything")
	}
	all := string(bytes.Join(captured, []byte("\n")))
	if strings.Contains(all, bearerToken) {
		t.Fatalf("bearer token leaked into logged events: %s", all)
	}
	if strings.Contains(all, resultNonce) {
		t.Fatalf("result nonce leaked into logged events: %s", all)
	}
}

func TestQueueAndProposalMutationsLogLifecycleEvents(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	queueBackend := &queueBackendSpy{}
	proposal, err := domain.NewProposal("proposal-1", domain.Casual, []string{"player-1", "player-2"}, now)
	if err != nil {
		t.Fatal(err)
	}
	proposalBackend := &proposalBackendSpy{proposal: proposal}
	var captured []observability.Event
	service := &Service{
		SessionBackend:  &sessionBackendSpy{},
		QueueBackend:    queueBackend,
		ProposalBackend: proposalBackend,
		Now:             func() time.Time { return now },
		Log:             func(event observability.Event) { captured = append(captured, event) },
	}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	auth := "Bearer session-1:token-1"
	request := func(method, path, body string, headers map[string]string) *http.Response {
		req, _ := http.NewRequest(method, server.URL+path, strings.NewReader(body))
		req.Header.Set("Authorization", auth)
		for key, value := range headers {
			req.Header.Set(key, value)
		}
		response, err := http.DefaultClient.Do(req)
		if err != nil {
			t.Fatal(err)
		}
		return response
	}

	create := request(http.MethodPost, "/v1/queue", `{"ticket_id":"ticket-1","playlist":"casual","client_build":"build-1","protocol_version":1}`, map[string]string{"Idempotency-Key": "log-create-key-123456"})
	if create.StatusCode != http.StatusCreated {
		t.Fatalf("create status = %d", create.StatusCode)
	}
	create.Body.Close()

	heartbeat := request(http.MethodPost, "/v1/queue/ticket-1/heartbeat", `{}`, map[string]string{"Idempotency-Key": "log-heartbeat-key-123456", "If-Match-Revision": "0"})
	if heartbeat.StatusCode != http.StatusOK {
		t.Fatalf("heartbeat status = %d", heartbeat.StatusCode)
	}
	heartbeat.Body.Close()

	cancel := request(http.MethodPost, "/v1/queue/ticket-1/cancel", `{}`, map[string]string{"Idempotency-Key": "log-cancel-key-123456", "If-Match-Revision": "0"})
	if cancel.StatusCode != http.StatusOK {
		t.Fatalf("cancel status = %d", cancel.StatusCode)
	}
	cancel.Body.Close()

	respond := request(http.MethodPost, "/v1/proposals/proposal-1/accept", `{}`, map[string]string{"Idempotency-Key": "log-respond-key-123456", "If-Match-Revision": "0"})
	if respond.StatusCode != http.StatusOK {
		t.Fatalf("proposal accept status = %d", respond.StatusCode)
	}
	respond.Body.Close()

	// Same stale revision again -- the real domain.Proposal.Respond behind
	// proposalBackendSpy fences this for real, unlike the dumb queue spy
	// above, so this proves the rejection path logs too.
	staleRespond := request(http.MethodPost, "/v1/proposals/proposal-1/accept", `{}`, map[string]string{"Idempotency-Key": "log-respond-key-234567", "If-Match-Revision": "0"})
	if staleRespond.StatusCode != http.StatusConflict {
		t.Fatalf("stale proposal accept status = %d", staleRespond.StatusCode)
	}
	staleRespond.Body.Close()

	want := []struct{ event, id, stage string }{
		{"queue_create", "ticket-1", "queued"},
		{"queue_heartbeat", "ticket-1", "queued"},
		{"queue_cancel", "ticket-1", "cancelled"},
		{"proposal_response", "proposal-1", "open"},
		{"proposal_response", "proposal-1", "rejected"},
	}
	if len(captured) != len(want) {
		t.Fatalf("captured %d events, want %d: %+v", len(captured), len(want), captured)
	}
	for i, w := range want {
		got := captured[i]
		gotID := got.QueueID
		if got.Event == "proposal_response" {
			gotID = got.ProposalID
		}
		if got.Event != w.event || gotID != w.id || got.Stage != w.stage {
			t.Fatalf("event[%d] = %+v, want {%s %s %s}", i, got, w.event, w.id, w.stage)
		}
	}
}

func TestServerRegistrationAPIRequiresBoundWorkloadAndValidDigest(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	binding := domain.WorkloadBinding{AllocationID: "allocation-1", MatchID: "match-1", ServerID: "server-1"}
	registrar := &serverRegistrarSpy{}
	service := &Service{Now: func() time.Time { return now }, WorkloadVerify: func(token string, _ time.Time) (domain.WorkloadBinding, error) {
		if token != "workload-token" {
			return domain.WorkloadBinding{}, errors.New("bad token")
		}
		return binding, nil
	}, ServerRegistrar: registrar}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	body := `{"match_id":"match-1","protocol_version":1,"image_digest":"sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa","assignment_ready":false}`
	req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/servers/server-1/register", strings.NewReader(body))
	req.Header.Set("Authorization", "Bearer workload-token")
	req.Header.Set("Idempotency-Key", "register-key-123456")
	response, err := http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusNoContent || registrar.calls != 1 || registrar.binding != binding || registrar.protocol != 1 || registrar.assignmentReady {
		t.Fatalf("status=%v err=%v registrar=%+v", response.StatusCode, err, registrar)
	}
	response.Body.Close()
	body = `{"match_id":"match-1","protocol_version":1,"image_digest":"bad","assignment_ready":false}`
	req, _ = http.NewRequest(http.MethodPost, server.URL+"/v1/servers/server-1/register", strings.NewReader(body))
	req.Header.Set("Authorization", "Bearer workload-token")
	req.Header.Set("Idempotency-Key", "register-key-123456")
	response, err = http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusUnprocessableEntity || registrar.calls != 1 {
		t.Fatalf("invalid registration status=%v err=%v calls=%d", response.StatusCode, err, registrar.calls)
	}
	response.Body.Close()
}

func TestServerMutationConflictsAreExportedAsADistinctPrometheusCounter(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	binding := domain.WorkloadBinding{AllocationID: "allocation-1", MatchID: "match-1", ServerID: "server-1"}
	registrar := &serverRegistrarSpy{err: domain.ErrConflict}
	metrics := observability.NewMetrics()
	service := &Service{Now: func() time.Time { return now }, Metrics: metrics, WorkloadVerify: func(token string, _ time.Time) (domain.WorkloadBinding, error) {
		if token != "workload-token" {
			return domain.WorkloadBinding{}, errors.New("bad token")
		}
		return binding, nil
	}, ServerRegistrar: registrar}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	body := `{"match_id":"match-1","protocol_version":1,"image_digest":"sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa","assignment_ready":false}`
	req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/servers/server-1/register", strings.NewReader(body))
	req.Header.Set("Authorization", "Bearer workload-token")
	req.Header.Set("Idempotency-Key", "register-key-123456")
	response, err := http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusConflict {
		t.Fatalf("status=%v err=%v", response.StatusCode, err)
	}
	response.Body.Close()

	metricsResponse, err := http.Get(server.URL + "/metrics")
	if err != nil {
		t.Fatal(err)
	}
	defer metricsResponse.Body.Close()
	exported, err := io.ReadAll(metricsResponse.Body)
	if err != nil {
		t.Fatal(err)
	}
	if !strings.Contains(string(exported), `cosmic_clash_api_server_conflicts_total{kind="register"} 1`) {
		t.Fatalf("register conflict was not exported: %s", exported)
	}
}

func TestServerShutdownAPIRequiresBoundWorkloadAndDelegatesAcknowledgement(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	binding := domain.WorkloadBinding{AllocationID: "allocation-1", MatchID: "match-1", ServerID: "server-1"}
	shutdowner := &serverShutdownerSpy{}
	service := &Service{Now: func() time.Time { return now }, WorkloadVerify: func(token string, at time.Time) (domain.WorkloadBinding, error) {
		if token != "workload-token" || !at.Equal(now) {
			t.Fatalf("verifier input=%q %v", token, at)
		}
		return binding, nil
	}, ServerShutdowner: shutdowner}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/servers/server-1/shutdown", strings.NewReader(`{"reason":"server_draining"}`))
	req.Header.Set("Authorization", "Bearer workload-token")
	req.Header.Set("Idempotency-Key", "shutdown-key-123456")
	response, err := http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusNoContent {
		t.Fatalf("status=%v err=%v", response.StatusCode, err)
	}
	response.Body.Close()
	if shutdowner.calls != 1 || shutdowner.binding != binding || shutdowner.reason != "server_draining" || shutdowner.key != "shutdown-key-123456" {
		t.Fatalf("shutdown=%+v", shutdowner)
	}

	req, _ = http.NewRequest(http.MethodPost, server.URL+"/v1/servers/server-1/shutdown", strings.NewReader(`{"reason":"bad\nreason"}`))
	req.Header.Set("Authorization", "Bearer workload-token")
	req.Header.Set("Idempotency-Key", "shutdown-key-123456")
	response, err = http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusUnprocessableEntity || shutdowner.calls != 1 {
		t.Fatalf("invalid shutdown status=%v err=%v calls=%d", response.StatusCode, err, shutdowner.calls)
	}
	response.Body.Close()
}

func TestServerConnectionAPIRequiresBoundWorkloadAndOpaqueAssignedPlayer(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	binding := domain.WorkloadBinding{AllocationID: "allocation-123456", MatchID: "match-1234567890", ServerID: "server-123456789"}
	recorder := &serverConnectionSpy{}
	service := &Service{Now: func() time.Time { return now }, WorkloadVerify: func(token string, _ time.Time) (domain.WorkloadBinding, error) {
		if token != "workload-token" {
			return domain.WorkloadBinding{}, errors.New("bad token")
		}
		return binding, nil
	}, ServerConnections: recorder}
	server := httptest.NewServer(service.Handler())
	defer server.Close()

	request := func(operation, serverID, playerID, token, key, bodySuffix string) (int, string) {
		body := fmt.Sprintf(`{"player_id":%q%s}`, playerID, bodySuffix)
		req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/servers/"+serverID+"/"+operation, strings.NewReader(body))
		req.Header.Set("Authorization", "Bearer "+token)
		req.Header.Set("Idempotency-Key", key)
		response, err := http.DefaultClient.Do(req)
		if err != nil {
			t.Fatal(err)
		}
		responseBody, _ := io.ReadAll(response.Body)
		response.Body.Close()
		return response.StatusCode, string(responseBody)
	}
	if got, body := request("connect", binding.ServerID, "player-123456789", "workload-token", "connect-player-123456789", `,"expected_generation":0`); got != http.StatusOK || !strings.Contains(body, `"generation":1`) {
		t.Fatalf("connection status = %d", got)
	}
	if recorder.connectCalls != 1 || recorder.binding != binding || recorder.playerID != "player-123456789" || recorder.expectedGeneration != 0 || recorder.key != "connect-player-123456789" {
		t.Fatalf("connection receipt = %+v", recorder)
	}
	if got, body := request("connect", binding.ServerID, "player-legacy-123456", "workload-token", "connect-legacy-123456", ""); got != http.StatusNoContent || body != "" {
		t.Fatalf("legacy connection status=%d body=%q", got, body)
	}
	if got, _ := request("connect", "server-000000000", "player-123456789", "workload-token", "connect-player-123456789", ""); got != http.StatusUnauthorized {
		t.Fatalf("wrong server status = %d", got)
	}
	if got, _ := request("connect", binding.ServerID, "short", "workload-token", "connect-player-short-123", ""); got != http.StatusUnprocessableEntity {
		t.Fatalf("short player status = %d", got)
	}
	if recorder.connectCalls != 2 {
		t.Fatalf("invalid receipts reached backend: %d", recorder.connectCalls)
	}
	if got, _ := request("disconnect", binding.ServerID, "player-123456789", "workload-token", "disconnect-player-123456789", `,"generation":1`); got != http.StatusNoContent {
		t.Fatalf("disconnect status = %d", got)
	}
	if recorder.disconnectCalls != 1 || recorder.generation != 1 {
		t.Fatalf("disconnect receipt = %+v", recorder)
	}
	if got, _ := request("disconnect", binding.ServerID, "player-123456789", "workload-token", "disconnect-zero-123456", ""); got != http.StatusUnprocessableEntity || recorder.disconnectCalls != 1 {
		t.Fatalf("zero-generation disconnect status=%d calls=%d", got, recorder.disconnectCalls)
	}
	recorder.err = errors.New("database unavailable")
	if got, _ := request("connect", binding.ServerID, "player-123456789", "workload-token", "connect-player-retry-123", `,"expected_generation":1`); got != http.StatusServiceUnavailable {
		t.Fatalf("recorder outage status = %d, want retryable 503", got)
	}
}

func TestMetricsEndpointExportsBoundedAPILatencyAndSkipsItsOwnScrape(t *testing.T) {
	metrics := observability.NewMetrics()
	service := &Service{Metrics: metrics, Now: time.Now}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	response, err := http.Get(server.URL + "/healthz")
	if err != nil {
		t.Fatal(err)
	}
	response.Body.Close()
	response, err = http.Get(server.URL + "/unknown/secret-token")
	if err != nil {
		t.Fatal(err)
	}
	response.Body.Close()
	response, err = http.Get(server.URL + "/metrics")
	if err != nil {
		t.Fatal(err)
	}
	defer response.Body.Close()
	body, err := io.ReadAll(response.Body)
	if err != nil {
		t.Fatal(err)
	}
	if response.StatusCode != http.StatusOK || !strings.Contains(string(body), `operation="other",status="4xx"`) || strings.Contains(string(body), "secret-token") {
		t.Fatalf("metrics status=%d body=%s", response.StatusCode, body)
	}
}

func TestControlPlaneLivenessAndDatastoreReadinessAreIndependent(t *testing.T) {
	ready := false
	checks := 0
	limiter, err := NewRateLimiter(1, time.Minute, 8)
	if err != nil {
		t.Fatal(err)
	}
	service := &Service{
		RateLimiter: limiter,
		Now:         func() time.Time { return time.Unix(1000, 0) },
		ReadinessCheck: func(context.Context) error {
			checks++
			if !ready {
				return errors.New("database unavailable")
			}
			return nil
		},
	}
	handler := service.Handler()
	status := func(method, path string) int {
		recorder := httptest.NewRecorder()
		handler.ServeHTTP(recorder, httptest.NewRequest(method, path, nil))
		return recorder.Code
	}
	if got := status(http.MethodGet, "/healthz"); got != http.StatusOK {
		t.Fatalf("liveness during datastore outage = %d", got)
	}
	if got := status(http.MethodGet, "/readyz"); got != http.StatusServiceUnavailable {
		t.Fatalf("readiness during datastore outage = %d", got)
	}
	ready = true
	if got := status(http.MethodGet, "/readyz"); got != http.StatusOK {
		t.Fatalf("recovered readiness = %d", got)
	}
	if got := status(http.MethodGet, "/healthz"); got != http.StatusOK {
		t.Fatalf("repeated probe was incorrectly rate limited: %d", got)
	}
	if checks != 2 {
		t.Fatalf("readiness checks = %d", checks)
	}
	if got := status(http.MethodPost, "/readyz"); got != http.StatusMethodNotAllowed {
		t.Fatalf("readiness mutation status = %d", got)
	}
}

func TestControlPlaneReadinessFailsClosedWithoutCheck(t *testing.T) {
	recorder := httptest.NewRecorder()
	(&Service{}).Handler().ServeHTTP(recorder, httptest.NewRequest(http.MethodGet, "/readyz", nil))
	if recorder.Code != http.StatusServiceUnavailable {
		t.Fatalf("unconfigured readiness status = %d", recorder.Code)
	}
}

func TestProbeAPIUsesServerEvidenceAndRejectsClientRTTField(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, err := sessions.Issue("player-a", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	called := false
	// A ProbeRecorder is required: accepting a probe without persisting it
	// reports success while leaving predicted_rtt empty, which silently keeps
	// the ticket invisible to the matcher.
	service := &Service{Sessions: sessions, Now: func() time.Time { return now }, ProbeRecorder: &probeRecorderSpy{}, Probe: func(_ context.Context, playerID, region string, location, nonce []byte, receivedAt time.Time) (domain.ProbeEvidence, []byte, error) {
		called = true
		if playerID != "player-a" || region != "EU" || string(location) != "opaque" || string(nonce) != "nonce" || !receivedAt.Equal(now) {
			t.Fatalf("probe provider arguments = %q %s %q %q %v", playerID, region, location, nonce, receivedAt)
		}
		return domain.ProbeEvidence{OpaqueLocation: location, Nonce: nonce, IssuedAt: now, Region: region, ServerRTT: 40 * time.Millisecond}, nonce, nil
	}}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	request := `{"opaque_location":"b3BhcXVl","nonce":"bm9uY2U="}`
	req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/probes/EU", strings.NewReader(request))
	req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
	response, err := http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusAccepted || !called {
		t.Fatalf("valid probe status=%v err=%v called=%v", response.StatusCode, err, called)
	}
	_ = response.Body.Close()
	request = `{"opaque_location":"b3BhcXVl","nonce":"bm9uY2U=","server_rtt_ms":1}`
	req, _ = http.NewRequest(http.MethodPost, server.URL+"/v1/probes/EU", strings.NewReader(request))
	req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
	response, err = http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusBadRequest {
		t.Fatalf("client RTT field status=%v err=%v", response.StatusCode, err)
	}
	_ = response.Body.Close()
}

func TestProbeAPIRecordsOnlyValidatedServerEvidence(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, _ := sessions.Issue("player-a", time.Hour, now)
	recorder := &probeRecorderSpy{}
	service := &Service{Sessions: sessions, Now: func() time.Time { return now }, ProbeRecorder: recorder, Probe: func(_ context.Context, _ string, region string, location, nonce []byte, _ time.Time) (domain.ProbeEvidence, []byte, error) {
		return domain.ProbeEvidence{OpaqueLocation: location, Nonce: nonce, IssuedAt: now, Region: region, ServerRTT: 37 * time.Millisecond}, nonce, nil
	}}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	req, _ := http.NewRequest(http.MethodPost, server.URL+"/v1/probes/NA", strings.NewReader(`{"opaque_location":"b3BhcXVl","nonce":"bm9uY2U="}`))
	req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
	response, err := http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusAccepted {
		t.Fatalf("status=%v err=%v", response.StatusCode, err)
	}
	response.Body.Close()
	if recorder.calls != 1 || recorder.last.player != "player-a" || recorder.last.region != "NA" || recorder.last.rtt != 37*time.Millisecond {
		t.Fatalf("recorded probe=%+v calls=%d", recorder.last, recorder.calls)
	}
	recorder.err = errors.New("database unavailable")
	req, _ = http.NewRequest(http.MethodPost, server.URL+"/v1/probes/NA", strings.NewReader(`{"opaque_location":"b3BhcXVl","nonce":"bm9uY2U="}`))
	req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
	response, err = http.DefaultClient.Do(req)
	if err != nil || response.StatusCode != http.StatusServiceUnavailable {
		t.Fatalf("persistence status=%v err=%v", response.StatusCode, err)
	}
	response.Body.Close()
}

func TestProposalRecoveryIsParticipantScopedAndExpiresAtReadBoundary(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	owner, ownerToken, err := sessions.Issue("player-a", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	other, otherToken, err := sessions.Issue("player-z", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	proposal, err := domain.NewProposal("proposal-recovery", domain.Casual, []string{"player-a", "player-b"}, now)
	if err != nil {
		t.Fatal(err)
	}
	current := now
	service := &Service{Sessions: sessions, Proposals: map[string]*domain.Proposal{proposal.ProposalID: &proposal}, Now: func() time.Time { return current }}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	get := func(session domain.Session, token string) (int, proposalResponse) {
		req, _ := http.NewRequest(http.MethodGet, server.URL+"/v1/proposals/proposal-recovery", nil)
		req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
		response, requestErr := http.DefaultClient.Do(req)
		if requestErr != nil {
			t.Fatal(requestErr)
		}
		defer response.Body.Close()
		var body proposalResponse
		if response.StatusCode == http.StatusOK {
			if err := json.NewDecoder(response.Body).Decode(&body); err != nil {
				t.Fatal(err)
			}
		}
		return response.StatusCode, body
	}
	status, recovered := get(owner, ownerToken)
	if status != http.StatusOK || recovered.State != string(domain.Open) || recovered.Revision != 0 {
		t.Fatalf("owner recovery status=%d body=%+v", status, recovered)
	}
	status, _ = get(other, otherToken)
	if status != http.StatusNotFound {
		t.Fatalf("non-participant recovery status=%d, want 404", status)
	}
	current = now.Add(domain.ProposalWindow)
	status, recovered = get(owner, ownerToken)
	if status != http.StatusOK || recovered.State != string(domain.Expired) || recovered.Revision != 1 {
		t.Fatalf("expired recovery status=%d body=%+v", status, recovered)
	}
}

func TestAssignmentRecoveryIsPlayerScopedAndRejectsExpiredOrMismatchedViews(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	sessions := domain.NewSessionStore()
	session, token, err := sessions.Issue("player-a", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	other, otherToken, err := sessions.Issue("player-z", time.Hour, now)
	if err != nil {
		t.Fatal(err)
	}
	current := now
	service := &Service{Sessions: sessions, Now: func() time.Time { return current }, Assignment: func(_ context.Context, _ string, matchID string, _ time.Time) (AssignmentView, error) {
		return AssignmentView{MatchID: matchID, ServerID: "server-1", PlayerID: "player-a", Slot: 2, ExpiresAt: now.Add(time.Minute), ProtocolVersion: 1, Transport: "enet", Endpoint: "127.0.0.1:30001", JoinAuthorisation: "signed-join"}, nil
	}}
	server := httptest.NewServer(service.Handler())
	defer server.Close()
	get := func(path string) (int, AssignmentView) {
		req, _ := http.NewRequest(http.MethodGet, server.URL+path, nil)
		req.Header.Set("Authorization", "Bearer "+session.SessionID+":"+token)
		response, requestErr := http.DefaultClient.Do(req)
		if requestErr != nil {
			t.Fatal(requestErr)
		}
		defer response.Body.Close()
		var view AssignmentView
		if response.StatusCode == http.StatusOK {
			if err := json.NewDecoder(response.Body).Decode(&view); err != nil {
				t.Fatal(err)
			}
		}
		return response.StatusCode, view
	}
	status, view := get("/v1/assignments/match-1")
	if status != http.StatusOK || view.PlayerID != "player-a" || view.Slot != 2 {
		t.Fatalf("assignment status=%d view=%+v", status, view)
	}
	req, _ := http.NewRequest(http.MethodGet, server.URL+"/v1/assignments/match-1", nil)
	req.Header.Set("Authorization", "Bearer "+other.SessionID+":"+otherToken)
	response, err := http.DefaultClient.Do(req)
	if err != nil {
		t.Fatal(err)
	}
	if response.StatusCode != http.StatusNotFound {
		t.Fatalf("misbound assignment status=%d, want 404", response.StatusCode)
	}
	response.Body.Close()
	status, _ = get("/v1/assignments/")
	if status != http.StatusNotFound {
		t.Fatalf("malformed assignment path status=%d", status)
	}
	current = now.Add(time.Minute)
	status, _ = get("/v1/assignments/match-1")
	if status != http.StatusServiceUnavailable {
		t.Fatalf("expired assignment status=%d", status)
	}
}

func TestAssignmentEventUsesAuthoritativeRevisionWithoutChangingResponseShape(t *testing.T) {
	now := time.Unix(1000, 0).UTC()
	view := AssignmentView{MatchID: "match-1", ServerID: "server-1", PlayerID: "player-a", Revision: 7}
	event := assignmentChangedEvent(view, now)
	if event.Revision != 7 || event.ResourceID != "match-1" || event.PlayerID != "player-a" {
		t.Fatalf("assignment event = %+v", event)
	}
	payload, err := json.Marshal(view)
	if err != nil {
		t.Fatal(err)
	}
	if strings.Contains(string(payload), "revision") {
		t.Fatalf("assignment response leaked event revision: %s", payload)
	}
}

func TestAssignmentEndpointValidationRejectsAmbiguousOrUnsafeEndpoints(t *testing.T) {
	for _, endpoint := range []string{"", "127.0.0.1", "127.0.0.1:0", "127.0.0.1:70000", "https://127.0.0.1:1", "127.0.0.1:1/path"} {
		if validAssignmentEndpoint(endpoint) {
			t.Fatalf("unsafe endpoint accepted: %q", endpoint)
		}
	}
	for _, endpoint := range []string{"127.0.0.1:1", "example.invalid:65535", "[2001:db8::1]:31001"} {
		if !validAssignmentEndpoint(endpoint) {
			t.Fatalf("valid endpoint rejected: %q", endpoint)
		}
	}
}