feat(protocol): negotiate display and native input

tests/go/protocol_test.go

@@ -1,6 +1,7 @@
 package protocol_test
 
 import (
+	"bytes"
 	"reflect"
 	"strings"
 	"testing"
@@ -22,6 +23,83 @@ func TestManifestRejectsForbiddenAndUnknownFields(t *testing.T) {
 	}
 }
 
+func TestDisplayModeIsOptionalStrictAndBounded(t *testing.T) {
+	displayType := reflect.TypeOf(protocol.DisplayMode{})
+	for _, field := range []struct {
+		owner reflect.Type
+		name  string
+	}{
+		{reflect.TypeOf(protocol.SessionRequest{}), "RequestedDisplayMode"},
+		{reflect.TypeOf(protocol.BrokerSession{}), "RequestedDisplayMode"},
+		{reflect.TypeOf(protocol.BrokerSession{}), "EffectiveDisplayMode"},
+		{reflect.TypeOf(protocol.ManifestProfile{}), "DisplayMode"},
+	} {
+		actual, ok := field.owner.FieldByName(field.name)
+		if !ok || actual.Type.Kind() != reflect.Pointer || actual.Type.Elem() != displayType {
+			t.Fatalf("%s.%s must be *DisplayMode, got %v", field.owner, field.name, actual.Type)
+		}
+	}
+
+	request := protocol.SessionRequest{
+		ClientDeviceID: "device-1", DeviceKeyID: "key-1", PoolID: "pool-1", IdempotencyKey: "request-1",
+		PolicySnapshot: protocol.AllocationPolicy{
+			MinimumKbps: 1000, TargetKbps: 2000, MaximumKbps: 3000, Tier: "standard",
+			Audience: "versevdi-gateway", Protocol: "verse", ProtocolVersion: 1,
+			GrantTTLSeconds: 60, ReservationLeaseSeconds: 300,
+		},
+	}
+	legacy, err := protocol.EncodeSessionRequest(request)
+	if err != nil {
+		t.Fatalf("EncodeSessionRequest legacy request: %v", err)
+	}
+	if bytes.Contains(legacy, []byte("requested_display_mode")) {
+		t.Fatalf("legacy request disclosed an absent display mode: %s", legacy)
+	}
+
+	mode := protocol.DisplayMode{ResolutionWidth: 2560, ResolutionHeight: 1440, Fps: 120}
+	request.RequestedDisplayMode = &mode
+	aware, err := protocol.EncodeSessionRequest(request)
+	if err != nil || !bytes.Contains(aware, []byte(`"requested_display_mode":{"resolution_width":2560,"resolution_height":1440,"fps":120}`)) {
+		t.Fatalf("display-aware request = %s, err = %v", aware, err)
+	}
+	decoded, err := protocol.DecodeSessionRequest(aware)
+	if err != nil || decoded.RequestedDisplayMode == nil || *decoded.RequestedDisplayMode != mode {
+		t.Fatalf("DecodeSessionRequest display mode = %+v, err = %v", decoded.RequestedDisplayMode, err)
+	}
+	nullMode := bytes.Replace(aware, []byte(`{"resolution_width":2560,"resolution_height":1440,"fps":120}`), []byte("null"), 1)
+	if _, err := protocol.DecodeSessionRequest(nullMode); err == nil {
+		t.Fatalf("DecodeSessionRequest accepted explicit null display mode: %s", nullMode)
+	}
+
+	profile := protocol.ManifestProfile{
+		ID:     "standard",
+		Bounds: protocol.ManifestBounds{MinimumKbps: 1000, TargetKbps: 2000, MaximumKbps: 3000},
+	}
+	legacyProfile, err := protocol.EncodeManifestProfile(profile)
+	if err != nil || bytes.Contains(legacyProfile, []byte("display_mode")) {
+		t.Fatalf("legacy profile = %s, err = %v", legacyProfile, err)
+	}
+	profile.DisplayMode = &mode
+	awareProfile, err := protocol.EncodeManifestProfile(profile)
+	if err != nil || !bytes.Contains(awareProfile, []byte(`"display_mode":{"resolution_width":2560,"resolution_height":1440,"fps":120}`)) {
+		t.Fatalf("display-aware profile = %s, err = %v", awareProfile, err)
+	}
+
+	for _, invalid := range []string{
+		`{"resolution_width":319,"resolution_height":1440,"fps":120}`,
+		`{"resolution_width":16385,"resolution_height":1440,"fps":120}`,
+		`{"resolution_width":2560,"resolution_height":199,"fps":120}`,
+		`{"resolution_width":2560,"resolution_height":8641,"fps":120}`,
+		`{"resolution_width":2560,"resolution_height":1440,"fps":0}`,
+		`{"resolution_width":2560,"resolution_height":1440,"fps":241}`,
+		`{"resolution_width":2560,"resolution_height":1440,"fps":120,"unknown":true}`,
+	} {
+		if _, err := protocol.DecodeDisplayMode([]byte(invalid)); err == nil {
+			t.Fatalf("DecodeDisplayMode accepted %s", invalid)
+		}
+	}
+}
+
 func TestPageInfoRejectsOutOfBoundsLimit(t *testing.T) {
 	if _, err := protocol.DecodePageInfo([]byte(`{"limit":101,"next_cursor":""}`)); err == nil {
 		t.Fatal("DecodePageInfo accepted limit above the contract maximum")