feat: string and message value renderers for textual (#13510)

## Description

Closes: #12713 
Refs: #12878

Sign mode textual value renderers for string and message.

### Author Checklist

*All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.*

I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/main/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/main/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/main/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

*All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.*

I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

tx/textual/internal/testdata/message.json

@@ -0,0 +1,139 @@
+[
+    {
+        "proto": {},
+        "screens": [
+            {"text": "Foo object"}
+        ]
+    },
+    {
+        "proto": {
+            "full_name": "nonempty"
+        },
+        "screens": [
+            {"text": "Foo object"},
+            {"text": "Full name: nonempty", "indent": 1}
+        ]
+    },
+    {
+        "proto": {
+            "full_name": "thing one",
+            "nickname": ":thing two"
+        },
+        "screens": [
+            {"text": "Foo object"},
+            {"text": "Full name: thing one", "indent": 1},
+            {"text": "Nickname: :thing two", "indent": 1}
+        ]
+    },
+    {
+        "proto": {
+            "full_name": "special child message",
+            "mtime": {
+                "seconds": 1136214245
+            }
+        },
+        "screens": [
+            {"text": "Foo object"},
+            {"text": "Full name: special child message", "indent": 1},
+            {"text": "Mtime: 2006-01-02T15:04:05Z", "indent": 1}
+        ]
+    },
+    {
+        "proto": {
+            "nickname": "empty child",
+            "left": {}
+        },
+        "screens": [
+            {"text": "Foo object"},
+            {"text": "Nickname: empty child", "indent": 1},
+            {"text": "Left: Foo object", "indent": 1}
+        ]
+    },
+    {
+        "proto": {
+            "nickname": "empty children",
+            "left": {},
+            "right": {},
+            "bar": {}
+        },
+        "screens": [
+            {"text": "Foo object"},
+            {"text": "Nickname: empty children", "indent": 1},
+            {"text": "Left: Foo object", "indent": 1},
+            {"text": "Right: Foo object", "indent": 1},
+            {"text": "Bar: Bar object", "indent": 1}
+        ]
+    },
+    {
+        "proto": {
+            "full_name": "subfield",
+            "left": {},
+            "right": {
+                "nickname": "junior"
+            },
+            "bar": {}
+        },
+        "screens": [
+            {"text": "Foo object"},
+            {"text": "Full name: subfield", "indent": 1},
+            {"text": "Left: Foo object", "indent": 1},
+            {"text": "Right: Foo object", "indent": 1},
+            {"text": "Nickname: junior", "indent": 2},
+            {"text": "Bar: Bar object", "indent": 1}
+        ]
+    },
+    {
+        "proto": {
+            "full_name": "deep",
+            "left": {
+                "left": {"nickname": "LL"},
+                "right": {"nickname": "LR"}
+            },
+            "right": {
+                "left": {"nickname": "RL"},
+                "right": {"nickname": "RR"}
+            }
+        },
+        "screens": [
+            {"text": "Foo object"},
+            {"text": "Full name: deep", "indent": 1},
+            {"text": "Left: Foo object", "indent": 1},
+            {"text": "Left: Foo object", "indent": 2},
+            {"text": "Nickname: LL", "indent": 3},
+            {"text": "Right: Foo object", "indent": 2},
+            {"text": "Nickname: LR", "indent": 3},
+            {"text": "Right: Foo object", "indent": 1},
+            {"text": "Left: Foo object", "indent": 2},
+            {"text": "Nickname: RL", "indent": 3},
+            {"text": "Right: Foo object", "indent": 2},
+            {"text": "Nickname: RR", "indent": 3}
+        ]
+    },
+    {
+        "proto": {
+            "full_name": " the kitchen sink ",
+            "mtime": {},
+            "left": {},
+            "right": {
+                "nickname": "blub",
+                "right": {},
+                "bar": {
+                    "bar_id": "quux",
+                    "data": [255, 254]
+                }
+            }
+        },
+        "screens": [
+            {"text": "Foo object"},
+            {"text": "Full name:  the kitchen sink ", "indent": 1},
+            {"text": "Mtime: 1970-01-01T00:00:00Z", "indent": 1},
+            {"text": "Left: Foo object", "indent": 1},
+            {"text": "Right: Foo object", "indent": 1},
+            {"text": "Nickname: blub", "indent": 2},
+            {"text": "Right: Foo object", "indent": 2},
+            {"text": "Bar: Bar object", "indent": 2},
+            {"text": "Bar id: quux", "indent": 3},
+            {"text": "Data: FFFE", "indent": 3}
+        ]
+    }
+]

tx/textual/internal/testdata/string.json

@@ -0,0 +1,11 @@
+[
+    {"text": ""},
+    {"text": "x"},
+    {"text": "foo"},
+    {"text": "\"able"},
+    {"text": "unresolved\nambiguities\r\ncost\rbillions"},
+    {"text": "stealth whitespace is significant   "},
+    {"text": "stealth whitespace snailed for your protection  @@"},
+    {"text": "co\u00F6peration"},
+    {"text": "JSON limits unicode to 16 bits, surrogates must be transmitted as-is \uD852\uDF62"}
+]

tx/textual/internal/testpb/1.proto

@@ -39,3 +39,19 @@ message A {
   double         DOUBLE   = 110;
   map<string, A> MAP      = 111;
 }
+
+// Foo is a sample message type used for testing message rendering.
+message Foo {
+  string full_name = 1;
+  string nickname = 2;
+  google.protobuf.Timestamp mtime = 3;
+  Foo left = 4;
+  Foo right = 5;
+  Bar bar = 8;  // skip some field numbers
+}
+
+// Bar is a sample message type used for testing message rendering.
+message Bar {
+  string bar_id = 1;
+  bytes data = 2;
+}

tx/textual/valuerenderer/message.go

@@ -0,0 +1,161 @@
+package valuerenderer
+
+import (
+	"context"
+	"fmt"
+	"sort"
+	"strings"
+
+	"google.golang.org/protobuf/reflect/protoreflect"
+	"google.golang.org/protobuf/reflect/protoregistry"
+)
+
+type messageValueRenderer struct {
+	tr      *Textual
+	msgDesc protoreflect.MessageDescriptor
+	fds     []protoreflect.FieldDescriptor
+}
+
+func NewMessageValueRenderer(t *Textual, msgDesc protoreflect.MessageDescriptor) ValueRenderer {
+	fields := msgDesc.Fields()
+	fds := make([]protoreflect.FieldDescriptor, 0, fields.Len())
+	for i := 0; i < fields.Len(); i++ {
+		fds = append(fds, fields.Get(i))
+	}
+	sort.Slice(fds, func(i, j int) bool { return fds[i].Number() < fds[j].Number() })
+
+	return &messageValueRenderer{tr: t, msgDesc: msgDesc, fds: fds}
+}
+
+func (mr *messageValueRenderer) header() string {
+	return fmt.Sprintf("%s object", mr.msgDesc.Name())
+}
+
+func (mr *messageValueRenderer) Format(ctx context.Context, v protoreflect.Value) ([]Screen, error) {
+	fullName := v.Message().Descriptor().FullName()
+	wantFullName := mr.msgDesc.FullName()
+	if fullName != wantFullName {
+		return nil, fmt.Errorf(`bad message type: want "%s", got "%s"`, wantFullName, fullName)
+	}
+
+	screens := make([]Screen, 1)
+	screens[0].Text = mr.header()
+
+	for _, fd := range mr.fds {
+		vr, err := mr.tr.GetValueRenderer(fd)
+		if err != nil {
+			return nil, err
+		}
+		// Skip default values.
+		if !v.Message().Has(fd) {
+			continue
+		}
+
+		subscreens, err := vr.Format(ctx, v.Message().Get(fd))
+		if err != nil {
+			return nil, err
+		}
+		if len(subscreens) == 0 {
+			return nil, fmt.Errorf("empty rendering for field %s", fd.Name())
+		}
+
+		headerScreen := Screen{
+			Text:   fmt.Sprintf("%s: %s", formatFieldName(string(fd.Name())), subscreens[0].Text),
+			Indent: subscreens[0].Indent + 1,
+			Expert: subscreens[0].Expert,
+		}
+		screens = append(screens, headerScreen)
+
+		for i := 1; i < len(subscreens); i++ {
+			extraScreen := Screen{
+				Text:   subscreens[i].Text,
+				Indent: subscreens[i].Indent + 1,
+				Expert: subscreens[i].Expert,
+			}
+			screens = append(screens, extraScreen)
+		}
+	}
+
+	return screens, nil
+}
+
+// formatFieldName formats a field name in sentence case, as specified in:
+// https://github.com/cosmos/cosmos-sdk/blob/b6f867d0b674d62e56b27aa4d00f5b6042ebac9e/docs/architecture/adr-050-sign-mode-textual-annex1.md?plain=1#L110
+func formatFieldName(name string) string {
+	if len(name) == 0 {
+		return name
+	}
+	return strings.ToTitle(name[0:1]) + strings.ReplaceAll(name[1:], "_", " ")
+}
+
+var nilValue = protoreflect.Value{}
+
+func (mr *messageValueRenderer) Parse(ctx context.Context, screens []Screen) (protoreflect.Value, error) {
+	if len(screens) == 0 {
+		return nilValue, fmt.Errorf("expect at least one screen")
+	}
+
+	wantHeader := fmt.Sprintf("%s object", mr.msgDesc.Name())
+	if screens[0].Text != wantHeader {
+		return nilValue, fmt.Errorf(`bad header: want "%s", got "%s"`, wantHeader, screens[0].Text)
+	}
+	if screens[0].Indent != 0 {
+		return nilValue, fmt.Errorf("bad message indentation: want 0, got %d", screens[0].Indent)
+	}
+
+	msgType, err := protoregistry.GlobalTypes.FindMessageByName(mr.msgDesc.FullName())
+	if err != nil {
+		return nilValue, err
+	}
+	msg := msgType.New()
+	idx := 1
+
+	for _, fd := range mr.fds {
+		if idx >= len(screens) {
+			// remaining fields are default
+			break
+		}
+
+		vr, err := mr.tr.GetValueRenderer(fd)
+		if err != nil {
+			return nilValue, err
+		}
+
+		if screens[idx].Indent != 1 {
+			return nilValue, fmt.Errorf("bad message indentation: want 1, got %d", screens[idx].Indent)
+		}
+
+		prefix := formatFieldName(string(fd.Name())) + ": "
+		if !strings.HasPrefix(screens[idx].Text, prefix) {
+			// we must have skipped this fd because of a default value
+			continue
+		}
+
+		// Make a new screen without the prefix
+		subscreens := make([]Screen, 1)
+		subscreens[0] = screens[idx]
+		subscreens[0].Text = strings.TrimPrefix(screens[idx].Text, prefix)
+		subscreens[0].Indent--
+		idx++
+
+		// Gather nested screens
+		for idx < len(screens) && screens[idx].Indent > 1 {
+			scr := screens[idx]
+			scr.Indent--
+			subscreens = append(subscreens, scr)
+			idx++
+		}
+
+		val, err := vr.Parse(ctx, subscreens)
+		if err != nil {
+			return nilValue, err
+		}
+		msg.Set(fd, val)
+	}
+
+	if idx > len(screens) {
+		return nilValue, fmt.Errorf("leftover screens")
+	}
+
+	return protoreflect.ValueOfMessage(msg), nil
+}

tx/textual/valuerenderer/message_test.go

@@ -0,0 +1,53 @@
+package valuerenderer_test
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"os"
+	"testing"
+
+	"cosmossdk.io/tx/textual/valuerenderer"
+	"github.com/stretchr/testify/require"
+
+	bankv1beta1 "cosmossdk.io/api/cosmos/bank/v1beta1"
+	"cosmossdk.io/tx/textual/internal/testpb"
+	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/reflect/protoreflect"
+)
+
+func EmptyCoinMetadataQuerier(ctx context.Context, denom string) (*bankv1beta1.Metadata, error) {
+	return nil, nil
+}
+
+type messageJsonTest struct {
+	Proto   *testpb.Foo
+	Screens []valuerenderer.Screen
+}
+
+func TestMessageJsonTestcases(t *testing.T) {
+	raw, err := os.ReadFile("../internal/testdata/message.json")
+	require.NoError(t, err)
+
+	var testcases []messageJsonTest
+	err = json.Unmarshal(raw, &testcases)
+	require.NoError(t, err)
+
+	tr := valuerenderer.NewTextual(EmptyCoinMetadataQuerier)
+	for i, tc := range testcases {
+		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
+			rend := valuerenderer.NewMessageValueRenderer(&tr, (&testpb.Foo{}).ProtoReflect().Descriptor())
+
+			screens, err := rend.Format(context.Background(), protoreflect.ValueOf(tc.Proto.ProtoReflect()))
+			require.NoError(t, err)
+			require.Equal(t, tc.Screens, screens)
+
+			val, err := rend.Parse(context.Background(), screens)
+			require.NoError(t, err)
+			msg := val.Message().Interface()
+			require.IsType(t, &testpb.Foo{}, msg)
+			foo := msg.(*testpb.Foo)
+			require.True(t, proto.Equal(foo, tc.Proto))
+		})
+	}
+}

tx/textual/valuerenderer/string.go

@@ -0,0 +1,28 @@
+package valuerenderer
+
+import (
+	"context"
+	"fmt"
+
+	"google.golang.org/protobuf/reflect/protoreflect"
+)
+
+type stringValueRenderer struct {
+}
+
+// NewStringValueRenderer returns a ValueRenderer for protocol buffer string values.
+// It renders the string as-is without quotation.
+func NewStringValueRenderer() ValueRenderer {
+	return stringValueRenderer{}
+}
+
+func (sr stringValueRenderer) Format(_ context.Context, v protoreflect.Value) ([]Screen, error) {
+	return []Screen{{Text: v.String()}}, nil
+}
+
+func (sr stringValueRenderer) Parse(_ context.Context, screens []Screen) (protoreflect.Value, error) {
+	if len(screens) != 1 {
+		return protoreflect.Value{}, fmt.Errorf("expected single screen: %v", screens)
+	}
+	return protoreflect.ValueOfString(screens[0].Text), nil
+}

tx/textual/valuerenderer/string_test.go

@@ -0,0 +1,55 @@
+package valuerenderer_test
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"os"
+	"testing"
+
+	"cosmossdk.io/tx/textual/valuerenderer"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/protobuf/reflect/protoreflect"
+)
+
+type stringJsonTest struct {
+	Text string
+}
+
+func TestStringJsonTestcases(t *testing.T) {
+	raw, err := os.ReadFile("../internal/testdata/string.json")
+	require.NoError(t, err)
+
+	var testcases []stringJsonTest
+	err = json.Unmarshal(raw, &testcases)
+	require.NoError(t, err)
+
+	for i, tc := range testcases {
+		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
+			rend := valuerenderer.NewStringValueRenderer()
+
+			screens, err := rend.Format(context.Background(), protoreflect.ValueOfString(tc.Text))
+			require.NoError(t, err)
+			require.Equal(t, 1, len(screens))
+			require.Equal(t, tc.Text, screens[0].Text)
+
+			val, err := rend.Parse(context.Background(), screens)
+			require.NoError(t, err)
+			require.Equal(t, tc.Text, val.String())
+		})
+	}
+}
+
+func TestStringHighUnicode(t *testing.T) {
+	// We cannot encode Unicode characters beyond the BMP directly in JSON,
+	// so this case must be a native Go test.
+	s := "\U00101234"
+	rend := valuerenderer.NewStringValueRenderer()
+	screens, err := rend.Format(context.Background(), protoreflect.ValueOfString(s))
+	require.NoError(t, err)
+	require.Equal(t, 1, len(screens))
+	require.Equal(t, s, screens[0].Text)
+	val, err := rend.Parse(context.Background(), screens)
+	require.NoError(t, err)
+	require.Equal(t, s, val.String())
+}

tx/textual/valuerenderer/valuerenderer.go

@@ -75,6 +75,9 @@ func (r Textual) GetValueRenderer(fd protoreflect.FieldDescriptor) (ValueRendere
 			return NewIntValueRenderer(), nil
 		}
 
+	case fd.Kind() == protoreflect.StringKind:
+		return stringValueRenderer{}, nil
+
 	case fd.Kind() == protoreflect.MessageKind:
 		md := fd.Message()
 		fullName := md.FullName()
@@ -83,8 +86,14 @@ func (r Textual) GetValueRenderer(fd protoreflect.FieldDescriptor) (ValueRendere
 		if found {
 			return vr, nil
 		}
-		// TODO default message renderer
-		return nil, fmt.Errorf("no value renderer for message %s", fullName)
+		if fd.IsMap() {
+			return nil, fmt.Errorf("value renderers cannot format value of type map")
+		}
+		if fd.IsList() {
+			// This will be implemented in https://github.com/cosmos/cosmos-sdk/issues/12714
+			return nil, fmt.Errorf("repeated field renderer not yet implemented")
+		}
+		return NewMessageValueRenderer(&r, md), nil
 
 	default:
 		return nil, fmt.Errorf("value renderers cannot format value of type %s", fd.Kind())