fix: correct Telegram update/keyboard models and harden env parsing

bot.go

@@ -184,21 +184,34 @@ func NewBot[T any](opts *BotOpts) *Bot[T] {
 //
 // Returns the first error encountered, if any.
 func (bot *Bot[T]) Close() error {
+	var firstErr error
+
 	if err := bot.uploader.Close(); err != nil {
 		bot.logger.Errorln(err)
+		if firstErr == nil {
+			firstErr = err
+		}
 	}
 	if err := bot.api.CloseApi(); err != nil {
 		bot.logger.Errorln(err)
+		if firstErr == nil {
+			firstErr = err
+		}
 	}
 	if bot.RequestLogger != nil {
 		if err := bot.RequestLogger.Close(); err != nil {
 			bot.logger.Errorln(err)
+			if firstErr == nil {
+				firstErr = err
+			}
 		}
 	}
 	if err := bot.logger.Close(); err != nil {
-		return err
+		if firstErr == nil {
+			firstErr = err
 		}
-	return nil
+	}
+	return firstErr
 }
 
 // initLoggers configures the main and optional request loggers.

bot_opts.go

@@ -85,10 +85,10 @@ func LoadOptsFromEnv() *BotOpts {
 		}
 	}
 
-	stringUpdateTypes := strings.Split(os.Getenv("UPDATE_TYPES"), ";")
+	stringUpdateTypes := splitEnvList(os.Getenv("UPDATE_TYPES"))
-	updateTypes := make([]tgapi.UpdateType, len(stringUpdateTypes))
+	updateTypes := make([]tgapi.UpdateType, 0, len(stringUpdateTypes))
-	for i, updateType := range stringUpdateTypes {
+	for _, updateType := range stringUpdateTypes {
-		updateTypes[i] = tgapi.UpdateType(updateType)
+		updateTypes = append(updateTypes, tgapi.UpdateType(updateType))
 	}
 
 	return &BotOpts{
@@ -222,5 +222,25 @@ func LoadPrefixesFromEnv() []string {
 	if !exists {
 		return []string{"/"}
 	}
-	return strings.Split(prefixesS, ";")
+	prefixes := splitEnvList(prefixesS)
+	if len(prefixes) == 0 {
+		return []string{"/"}
+	}
+	return prefixes
+}
+
+func splitEnvList(value string) []string {
+	if value == "" {
+		return nil
+	}
+	parts := strings.Split(value, ";")
+	out := make([]string, 0, len(parts))
+	for _, part := range parts {
+		part = strings.TrimSpace(part)
+		if part == "" {
+			continue
+		}
+		out = append(out, part)
+	}
+	return out
 }

bot_opts_test.go

@@ -0,0 +1,47 @@
+package laniakea
+
+import (
+	"reflect"
+	"testing"
+
+	"git.nix13.pw/scuroneko/laniakea/tgapi"
+)
+
+func TestLoadOptsFromEnvIgnoresEmptyUpdateTypes(t *testing.T) {
+	t.Setenv("UPDATE_TYPES", "")
+
+	opts := LoadOptsFromEnv()
+	if len(opts.UpdateTypes) != 0 {
+		t.Fatalf("expected no update types, got %v", opts.UpdateTypes)
+	}
+}
+
+func TestLoadOptsFromEnvSplitsAndTrimsUpdateTypes(t *testing.T) {
+	t.Setenv("UPDATE_TYPES", "message; ; callback_query ")
+
+	opts := LoadOptsFromEnv()
+	want := []tgapi.UpdateType{tgapi.UpdateTypeMessage, tgapi.UpdateTypeCallbackQuery}
+	if !reflect.DeepEqual(opts.UpdateTypes, want) {
+		t.Fatalf("unexpected update types: got %v want %v", opts.UpdateTypes, want)
+	}
+}
+
+func TestLoadPrefixesFromEnvDefaultsOnEmptyValue(t *testing.T) {
+	t.Setenv("PREFIXES", "")
+
+	got := LoadPrefixesFromEnv()
+	want := []string{"/"}
+	if !reflect.DeepEqual(got, want) {
+		t.Fatalf("unexpected prefixes: got %v want %v", got, want)
+	}
+}
+
+func TestLoadPrefixesFromEnvDropsEmptyValues(t *testing.T) {
+	t.Setenv("PREFIXES", "/; ; ! ")
+
+	got := LoadPrefixesFromEnv()
+	want := []string{"/", "!"}
+	if !reflect.DeepEqual(got, want) {
+		t.Fatalf("unexpected prefixes: got %v want %v", got, want)
+	}
+}

cmd_generator.go

@@ -100,17 +100,17 @@ func gatherCommands[T any](bot *Bot[T]) []tgapi.BotCommand {
 //	    log.Fatal(err)
 //	}
 func (bot *Bot[T]) AutoGenerateCommands() error {
+	commands := gatherCommands(bot)
+	if len(commands) > 100 {
+		return ErrTooManyCommands
+	}
+
 	// Clear existing commands to avoid duplication or stale entries
 	_, err := bot.api.DeleteMyCommands(tgapi.DeleteMyCommandsP{})
 	if err != nil {
 		return fmt.Errorf("failed to delete existing commands: %w", err)
 	}
 
-	commands := gatherCommands(bot)
-	if len(commands) > 100 {
-		return ErrTooManyCommands
-	}
-
 	// Register commands for each scope
 	scopes := []*tgapi.BotCommandScope{
 		{Type: tgapi.BotCommandScopePrivateType},
@@ -148,15 +148,16 @@ func (bot *Bot[T]) AutoGenerateCommands() error {
 //	    log.Fatal(err)
 //	}
 func (bot *Bot[T]) AutoGenerateCommandsForScope(scope *tgapi.BotCommandScope) error {
-	_, err := bot.api.DeleteMyCommands(tgapi.DeleteMyCommandsP{Scope: scope})
-	if err != nil {
-		return fmt.Errorf("failed to delete existing commands: %w", err)
-	}
 	commands := gatherCommands(bot)
 	if len(commands) > 100 {
 		return ErrTooManyCommands
 	}
 
+	_, err := bot.api.DeleteMyCommands(tgapi.DeleteMyCommandsP{Scope: scope})
+	if err != nil {
+		return fmt.Errorf("failed to delete existing commands: %w", err)
+	}
+
 	_, err = bot.api.SetMyCommands(tgapi.SetMyCommandsP{
 		Commands: commands,
 		Scope:    scope,

cmd_generator_test.go

@@ -0,0 +1,64 @@
+package laniakea
+
+import (
+	"errors"
+	"io"
+	"net/http"
+	"strconv"
+	"strings"
+	"sync/atomic"
+	"testing"
+
+	"git.nix13.pw/scuroneko/laniakea/tgapi"
+	"git.nix13.pw/scuroneko/slog"
+)
+
+type roundTripFunc func(*http.Request) (*http.Response, error)
+
+func (fn roundTripFunc) RoundTrip(req *http.Request) (*http.Response, error) {
+	return fn(req)
+}
+
+func TestAutoGenerateCommandsChecksLimitBeforeDelete(t *testing.T) {
+	var calls atomic.Int64
+	client := &http.Client{
+		Transport: roundTripFunc(func(req *http.Request) (*http.Response, error) {
+			calls.Add(1)
+			return &http.Response{
+				StatusCode: http.StatusOK,
+				Header:     http.Header{"Content-Type": []string{"application/json"}},
+				Body:       io.NopCloser(strings.NewReader(`{"ok":true,"result":true}`)),
+			}, nil
+		}),
+	}
+	api := tgapi.NewAPI(
+		tgapi.NewAPIOpts("token").
+			SetAPIUrl("https://example.test").
+			SetHTTPClient(client),
+	)
+	defer func() {
+		if err := api.CloseApi(); err != nil {
+			t.Fatalf("CloseApi returned error: %v", err)
+		}
+	}()
+
+	plugin := NewPlugin[NoDB]("overflow")
+	exec := func(ctx *MsgContext, db *NoDB) {}
+	for i := 0; i < 101; i++ {
+		plugin.AddCommand(NewCommand(exec, "cmd"+strconv.Itoa(i)))
+	}
+
+	bot := &Bot[NoDB]{
+		api:     api,
+		logger:  slog.CreateLogger(),
+		plugins: []Plugin[NoDB]{*plugin},
+	}
+
+	err := bot.AutoGenerateCommands()
+	if !errors.Is(err, ErrTooManyCommands) {
+		t.Fatalf("expected ErrTooManyCommands, got %v", err)
+	}
+	if calls.Load() != 0 {
+		t.Fatalf("expected no HTTP calls before limit validation, got %d", calls.Load())
+	}
+}

go.mod

@@ -3,8 +3,8 @@ module git.nix13.pw/scuroneko/laniakea
 go 1.26
 
 require (
-	git.nix13.pw/scuroneko/extypes v1.2.1
+	git.nix13.pw/scuroneko/extypes v1.2.2
-	git.nix13.pw/scuroneko/slog v1.0.2
+	git.nix13.pw/scuroneko/slog v1.1.2
 	github.com/alitto/pond/v2 v2.7.0
 	golang.org/x/time v0.15.0
 )

go.sum

@@ -1,7 +1,7 @@
-git.nix13.pw/scuroneko/extypes v1.2.1 h1:IYrOjnWKL2EAuJYtYNa+luB1vBe6paE8VY/YD+5/RpQ=
+git.nix13.pw/scuroneko/extypes v1.2.2 h1:N54c1ejrPs1yfIkvYuwqI7B1+8S9mDv2GqQA6sct4dk=
-git.nix13.pw/scuroneko/extypes v1.2.1/go.mod h1:uZVs8Yo3RrYAG9dMad6qR6lsYY67t+459D9c65QAYAw=
+git.nix13.pw/scuroneko/extypes v1.2.2/go.mod h1:b4XYk1OW1dVSiE2MT/OMuX/K/UItf1swytX6eroVYnk=
-git.nix13.pw/scuroneko/slog v1.0.2 h1:vZyUROygxC2d5FJHUQM/30xFEHY1JT/aweDZXA4rm2g=
+git.nix13.pw/scuroneko/slog v1.1.2 h1:pl7tV5FN25Yso7sLYoOgBXi9+jLo5BDJHWmHlNPjpY0=
-git.nix13.pw/scuroneko/slog v1.0.2/go.mod h1:3Qm2wzkR5KjwOponMfG7TcGSDjmYaFqRAmLvSPTuWJI=
+git.nix13.pw/scuroneko/slog v1.1.2/go.mod h1:UcfRIHDqpVQHahBGM93awLDK8//AsAvOqBwwbWqMkjM=
 github.com/alitto/pond/v2 v2.7.0 h1:c76L+yN916m/DRXjGCeUBHHu92uWnh/g1bwVk4zyyXg=
 github.com/alitto/pond/v2 v2.7.0/go.mod h1:xkjYEgQ05RSpWdfSd1nM3OVv7TBhLdy7rMp3+2Nq+yE=
 github.com/fatih/color v1.18.0 h1:S8gINlzdQ840/4pfAwic/ZE0djQEH3wM94VfqLTZcOM=

handler.go

@@ -138,6 +138,9 @@ func (bot *Bot[T]) handleCallback(update *tgapi.Update, ctx *MsgContext) {
 
 func (bot *Bot[T]) checkPrefixes(text string) (string, bool) {
 	for _, prefix := range bot.prefixes {
+		if prefix == "" {
+			continue
+		}
 		if strings.HasPrefix(text, prefix) {
 			return prefix, true
 		}

handler_test.go

@@ -0,0 +1,14 @@
+package laniakea
+
+import "testing"
+
+func TestCheckPrefixesSkipsEmptyPrefixes(t *testing.T) {
+	bot := &Bot[NoDB]{prefixes: []string{"", "/"}}
+
+	if prefix, ok := bot.checkPrefixes("hello"); ok {
+		t.Fatalf("unexpected prefix match for plain text: %q", prefix)
+	}
+	if prefix, ok := bot.checkPrefixes("/start"); !ok || prefix != "/" {
+		t.Fatalf("unexpected prefix result: prefix=%q ok=%v", prefix, ok)
+	}
+}

msg_context.go

@@ -270,6 +270,9 @@ func (ctx *MsgContext) answerPhoto(photoId, text string, kb *InlineKeyboard, par
 	if ctx.Msg.MessageThreadID > 0 {
 		params.MessageThreadID = ctx.Msg.MessageThreadID
 	}
+	if ctx.Msg.DirectMessageTopic != nil {
+		params.DirectMessagesTopicID = int(ctx.Msg.DirectMessageTopic.TopicID)
+	}
 
 	msg, err := ctx.Api.SendPhoto(params)
 	if err != nil {

msg_context_test.go

@@ -0,0 +1,64 @@
+package laniakea
+
+import (
+	"encoding/json"
+	"io"
+	"net/http"
+	"strings"
+	"testing"
+
+	"git.nix13.pw/scuroneko/laniakea/tgapi"
+	"git.nix13.pw/scuroneko/slog"
+)
+
+func TestAnswerPhotoIncludesDirectMessagesTopicID(t *testing.T) {
+	var gotBody map[string]any
+
+	client := &http.Client{
+		Transport: roundTripFunc(func(req *http.Request) (*http.Response, error) {
+			body, err := io.ReadAll(req.Body)
+			if err != nil {
+				t.Fatalf("failed to read request body: %v", err)
+			}
+			if err := json.Unmarshal(body, &gotBody); err != nil {
+				t.Fatalf("failed to decode request body: %v", err)
+			}
+			return &http.Response{
+				StatusCode: http.StatusOK,
+				Header:     http.Header{"Content-Type": []string{"application/json"}},
+				Body:       io.NopCloser(strings.NewReader(`{"ok":true,"result":{"message_id":9,"date":1}}`)),
+			}, nil
+		}),
+	}
+
+	api := tgapi.NewAPI(
+		tgapi.NewAPIOpts("token").
+			SetAPIUrl("https://example.test").
+			SetHTTPClient(client),
+	)
+	defer func() {
+		if err := api.CloseApi(); err != nil {
+			t.Fatalf("CloseApi returned error: %v", err)
+		}
+	}()
+
+	ctx := &MsgContext{
+		Api: api,
+		Msg: &tgapi.Message{
+			Chat:               &tgapi.Chat{ID: 42, Type: string(tgapi.ChatTypePrivate)},
+			DirectMessageTopic: &tgapi.DirectMessageTopic{TopicID: 77},
+		},
+		botLogger: slog.CreateLogger(),
+	}
+
+	answer := ctx.AnswerPhoto("photo-id", "caption")
+	if answer == nil {
+		t.Fatal("expected answer message")
+	}
+	if answer.MessageID != 9 {
+		t.Fatalf("unexpected message id: %d", answer.MessageID)
+	}
+	if got := gotBody["direct_messages_topic_id"]; got != float64(77) {
+		t.Fatalf("unexpected direct_messages_topic_id: %v", got)
+	}
+}

plugins.go

@@ -23,11 +23,11 @@ const (
 
 var (
 	// CommandRegexInt matches one or more digits.
-	CommandRegexInt = regexp.MustCompile(`\d+`)
+	CommandRegexInt = regexp.MustCompile(`^\d+$`)
 	// CommandRegexString matches any non-empty string.
-	CommandRegexString = regexp.MustCompile(`.+`)
+	CommandRegexString = regexp.MustCompile(`^.+$`)
 	// CommandRegexBool matches true or false.
-	CommandRegexBool = regexp.MustCompile(`true|false`)
+	CommandRegexBool = regexp.MustCompile(`^(true|false)$`)
 )
 
 // ErrCmdArgCountMismatch is returned when the number of provided arguments
@@ -64,6 +64,7 @@ func (c *CommandArg) SetValueType(t CommandValueType) *CommandArg {
 	case CommandValueAnyType:
 		regex = nil // Skip validation
 	}
+	c.valueType = t
 	c.regex = regex
 	return c
 }

plugins_test.go

@@ -0,0 +1,24 @@
+package laniakea
+
+import (
+	"errors"
+	"testing"
+)
+
+func TestValidateArgsRequiresFullMatch(t *testing.T) {
+	intCmd := NewCommand[NoDB](func(ctx *MsgContext, db *NoDB) {}, "int", *NewCommandArg("n").SetValueType(CommandValueIntType).SetRequired())
+	if err := intCmd.validateArgs([]string{"123"}); err != nil {
+		t.Fatalf("expected valid integer argument, got %v", err)
+	}
+	if err := intCmd.validateArgs([]string{"123abc"}); !errors.Is(err, ErrCmdArgRegexpMismatch) {
+		t.Fatalf("expected ErrCmdArgRegexpMismatch for partial int match, got %v", err)
+	}
+
+	boolCmd := NewCommand[NoDB](func(ctx *MsgContext, db *NoDB) {}, "bool", *NewCommandArg("flag").SetValueType(CommandValueBoolType).SetRequired())
+	if err := boolCmd.validateArgs([]string{"false"}); err != nil {
+		t.Fatalf("expected valid bool argument, got %v", err)
+	}
+	if err := boolCmd.validateArgs([]string{"falsey"}); !errors.Is(err, ErrCmdArgRegexpMismatch) {
+		t.Fatalf("expected ErrCmdArgRegexpMismatch for partial bool match, got %v", err)
+	}
+}

tgapi/api.go

@@ -202,7 +202,6 @@ func (r TelegramRequest[R, P]) doRequest(ctx context.Context, api *API) (R, erro
 	req.Header.Set("Content-Type", "application/json")
 	req.Header.Set("Accept", "application/json")
 	req.Header.Set("User-Agent", fmt.Sprintf("Laniakea/%s", utils.VersionString))
-	req.Header.Set("Accept-Encoding", "gzip")
 
 	for {
 		// Apply rate limiting before making the request

tgapi/api_test.go

@@ -0,0 +1,56 @@
+package tgapi
+
+import (
+	"io"
+	"net/http"
+	"strings"
+	"testing"
+)
+
+type roundTripFunc func(*http.Request) (*http.Response, error)
+
+func (fn roundTripFunc) RoundTrip(req *http.Request) (*http.Response, error) {
+	return fn(req)
+}
+
+func TestAPILeavesAcceptEncodingToHTTPTransport(t *testing.T) {
+	var gotPath string
+	var gotAcceptEncoding string
+
+	client := &http.Client{
+		Transport: roundTripFunc(func(req *http.Request) (*http.Response, error) {
+			gotPath = req.URL.Path
+			gotAcceptEncoding = req.Header.Get("Accept-Encoding")
+			return &http.Response{
+				StatusCode: http.StatusOK,
+				Header:     http.Header{"Content-Type": []string{"application/json"}},
+				Body:       io.NopCloser(strings.NewReader(`{"ok":true,"result":{"id":1,"is_bot":true,"first_name":"Test"}}`)),
+			}, nil
+		}),
+	}
+
+	api := NewAPI(
+		NewAPIOpts("token").
+			SetAPIUrl("https://example.test").
+			SetHTTPClient(client),
+	)
+	defer func() {
+		if err := api.CloseApi(); err != nil {
+			t.Fatalf("CloseApi returned error: %v", err)
+		}
+	}()
+
+	user, err := api.GetMe()
+	if err != nil {
+		t.Fatalf("GetMe returned error: %v", err)
+	}
+	if user.FirstName != "Test" {
+		t.Fatalf("unexpected first name: %q", user.FirstName)
+	}
+	if gotPath != "/bottoken/getMe" {
+		t.Fatalf("unexpected request path: %s", gotPath)
+	}
+	if gotAcceptEncoding != "" {
+		t.Fatalf("expected empty Accept-Encoding header, got %q", gotAcceptEncoding)
+	}
+}

tgapi/business_types.go

@@ -60,6 +60,14 @@ type BusinessConnection struct {
 	IsEnabled  bool               `json:"is_enabled"`
 }
 
+// BusinessMessagesDeleted is received when messages are deleted from a connected business account.
+// See https://core.telegram.org/bots/api#businessmessagesdeleted
+type BusinessMessagesDeleted struct {
+	BusinessConnectionID string `json:"business_connection_id"`
+	Chat                 Chat   `json:"chat"`
+	MessageIDs           []int  `json:"message_ids"`
+}
+
 // InputStoryContentType indicates the type of input story content.
 type InputStoryContentType string
 

tgapi/messages_types.go

@@ -144,7 +144,7 @@ type LinkPreviewOptions struct {
 type ReplyMarkup struct {
 	InlineKeyboard [][]InlineKeyboardButton `json:"inline_keyboard,omitempty"`
 
-	Keyboard              [][]int `json:"keyboard,omitempty"`
+	Keyboard              [][]KeyboardButton `json:"keyboard,omitempty"`
 	IsPersistent          bool               `json:"is_persistent,omitempty"`
 	ResizeKeyboard        bool               `json:"resize_keyboard,omitempty"`
 	OneTimeKeyboard       bool               `json:"one_time_keyboard,omitempty"`
@@ -165,6 +165,60 @@ type InlineKeyboardMarkup struct {
 // KeyboardButtonStyle represents the style of a keyboard button.
 type KeyboardButtonStyle string
 
+const (
+	KeyboardButtonStyleDanger  KeyboardButtonStyle = "danger"
+	KeyboardButtonStyleSuccess KeyboardButtonStyle = "success"
+	KeyboardButtonStylePrimary KeyboardButtonStyle = "primary"
+)
+
+// KeyboardButton represents one button of the reply keyboard.
+// See https://core.telegram.org/bots/api#keyboardbutton
+type KeyboardButton struct {
+	Text              string                      `json:"text"`
+	IconCustomEmojiID string                      `json:"icon_custom_emoji_id,omitempty"`
+	Style             KeyboardButtonStyle         `json:"style,omitempty"`
+	RequestUsers      *KeyboardButtonRequestUsers `json:"request_users,omitempty"`
+	RequestChat       *KeyboardButtonRequestChat  `json:"request_chat,omitempty"`
+	RequestContact    bool                        `json:"request_contact,omitempty"`
+	RequestLocation   bool                        `json:"request_location,omitempty"`
+	RequestPoll       *KeyboardButtonPollType     `json:"request_poll,omitempty"`
+	WebApp            *WebAppInfo                 `json:"web_app,omitempty"`
+}
+
+// KeyboardButtonRequestUsers defines criteria used to request suitable users.
+// See https://core.telegram.org/bots/api#keyboardbuttonrequestusers
+type KeyboardButtonRequestUsers struct {
+	RequestID       int   `json:"request_id"`
+	UserIsBot       *bool `json:"user_is_bot,omitempty"`
+	UserIsPremium   *bool `json:"user_is_premium,omitempty"`
+	MaxQuantity     int   `json:"max_quantity,omitempty"`
+	RequestName     bool  `json:"request_name,omitempty"`
+	RequestUsername bool  `json:"request_username,omitempty"`
+	RequestPhoto    bool  `json:"request_photo,omitempty"`
+}
+
+// KeyboardButtonRequestChat defines criteria used to request a suitable chat.
+// See https://core.telegram.org/bots/api#keyboardbuttonrequestchat
+type KeyboardButtonRequestChat struct {
+	RequestID               int                      `json:"request_id"`
+	ChatIsChannel           bool                     `json:"chat_is_channel"`
+	ChatIsForum             *bool                    `json:"chat_is_forum,omitempty"`
+	ChatHasUsername         *bool                    `json:"chat_has_username,omitempty"`
+	ChatIsCreated           *bool                    `json:"chat_is_created,omitempty"`
+	UserAdministratorRights *ChatAdministratorRights `json:"user_administrator_rights,omitempty"`
+	BotAdministratorRights  *ChatAdministratorRights `json:"bot_administrator_rights,omitempty"`
+	BotIsMember             bool                     `json:"bot_is_member,omitempty"`
+	RequestTitle            bool                     `json:"request_title,omitempty"`
+	RequestUsername         bool                     `json:"request_username,omitempty"`
+	RequestPhoto            bool                     `json:"request_photo,omitempty"`
+}
+
+// KeyboardButtonPollType represents the type of a poll that may be created from a keyboard button.
+// See https://core.telegram.org/bots/api#keyboardbuttonpolltype
+type KeyboardButtonPollType struct {
+	Type PollType `json:"type,omitempty"`
+}
+
 // InlineKeyboardButton represents one button of an inline keyboard.
 // See https://core.telegram.org/bots/api#inlinekeyboardbutton
 type InlineKeyboardButton struct {
@@ -178,7 +232,12 @@ type InlineKeyboardButton struct {
 // ReplyKeyboardMarkup represents a custom keyboard with reply options.
 // See https://core.telegram.org/bots/api#replykeyboardmarkup
 type ReplyKeyboardMarkup struct {
-	Keyboard [][]int `json:"keyboard"`
+	Keyboard              [][]KeyboardButton `json:"keyboard"`
+	IsPersistent          bool               `json:"is_persistent,omitempty"`
+	ResizeKeyboard        bool               `json:"resize_keyboard,omitempty"`
+	OneTimeKeyboard       bool               `json:"one_time_keyboard,omitempty"`
+	InputFieldPlaceholder string             `json:"input_field_placeholder,omitempty"`
+	Selective             bool               `json:"selective,omitempty"`
 }
 
 // CallbackQuery represents an incoming callback query from a callback button in an inline keyboard.
@@ -238,7 +297,8 @@ const (
 	ChatActionUploadDocument  ChatActionType = "upload_document"
 	ChatActionChooseSticker   ChatActionType = "choose_sticker"
 	ChatActionFindLocation    ChatActionType = "find_location"
-	ChatActionUploadVideoNone ChatActionType = "upload_video_none"
+	ChatActionUploadVideoNote ChatActionType = "upload_video_note"
+	ChatActionUploadVideoNone ChatActionType = ChatActionUploadVideoNote
 )
 
 // MessageReactionUpdated represents a change of a reaction on a message.

tgapi/messages_types_test.go

@@ -0,0 +1,37 @@
+package tgapi
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+)
+
+func TestReplyKeyboardMarkupMarshalsKeyboardButtons(t *testing.T) {
+	markup := ReplyKeyboardMarkup{
+		Keyboard: [][]KeyboardButton{{
+			{
+				Text:        "Create poll",
+				RequestPoll: &KeyboardButtonPollType{Type: PollTypeQuiz},
+			},
+		}},
+	}
+
+	data, err := json.Marshal(markup)
+	if err != nil {
+		t.Fatalf("Marshal returned error: %v", err)
+	}
+
+	got := string(data)
+	if !strings.Contains(got, `"keyboard":[[{"text":"Create poll","request_poll":{"type":"quiz"}}]]`) {
+		t.Fatalf("unexpected reply keyboard JSON: %s", got)
+	}
+}
+
+func TestChatActionUploadVideoNoteValue(t *testing.T) {
+	if ChatActionUploadVideoNote != "upload_video_note" {
+		t.Fatalf("unexpected chat action value: %q", ChatActionUploadVideoNote)
+	}
+	if ChatActionUploadVideoNone != ChatActionUploadVideoNote {
+		t.Fatalf("expected deprecated alias to match upload_video_note, got %q", ChatActionUploadVideoNone)
+	}
+}

tgapi/methods.go

@@ -1,9 +1,12 @@
 package tgapi
 
 import (
+	"context"
 	"fmt"
 	"io"
 	"net/http"
+
+	"git.nix13.pw/scuroneko/laniakea/utils"
 )
 
 // UpdateParams holds parameters for the getUpdates method.
@@ -12,7 +15,7 @@ type UpdateParams struct {
 	Offset         *int         `json:"offset,omitempty"`
 	Limit          *int         `json:"limit,omitempty"`
 	Timeout        *int         `json:"timeout,omitempty"`
-	AllowedUpdates []UpdateType `json:"allowed_updates"`
+	AllowedUpdates []UpdateType `json:"allowed_updates,omitempty"`
 }
 
 // GetMe returns basic information about the bot.
@@ -103,13 +106,31 @@ func (api *API) GetFile(params GetFileP) (File, error) {
 // The link is usually obtained from File.FilePath.
 // See https://core.telegram.org/bots/api#file
 func (api *API) GetFileByLink(link string) ([]byte, error) {
-	u := fmt.Sprintf("https://api.telegram.org/file/bot%s/%s", api.token, link)
+	methodPrefix := ""
-	res, err := http.Get(u)
+	if api.useTestServer {
+		methodPrefix = "/test"
+	}
+	u := fmt.Sprintf("%s/file/bot%s%s/%s", api.apiUrl, api.token, methodPrefix, link)
+
+	req, err := http.NewRequestWithContext(context.Background(), http.MethodGet, u, nil)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("User-Agent", fmt.Sprintf("Laniakea/%s", utils.VersionString))
+
+	res, err := api.client.Do(req)
 	if err != nil {
 		return nil, err
 	}
 	defer func() {
 		_ = res.Body.Close()
 	}()
+	if res.StatusCode < http.StatusOK || res.StatusCode >= http.StatusMultipleChoices {
+		body, readErr := io.ReadAll(io.LimitReader(res.Body, 4<<10))
+		if readErr != nil {
+			return nil, fmt.Errorf("unexpected status %d", res.StatusCode)
+		}
+		return nil, fmt.Errorf("unexpected status %d: %s", res.StatusCode, string(body))
+	}
 	return io.ReadAll(res.Body)
 }

tgapi/methods_test.go

@@ -0,0 +1,115 @@
+package tgapi
+
+import (
+	"encoding/json"
+	"io"
+	"net/http"
+	"strings"
+	"testing"
+)
+
+func TestGetFileByLinkUsesConfiguredAPIURL(t *testing.T) {
+	var gotPath string
+
+	client := &http.Client{
+		Transport: roundTripFunc(func(req *http.Request) (*http.Response, error) {
+			gotPath = req.URL.Path
+			return &http.Response{
+				StatusCode: http.StatusOK,
+				Body:       io.NopCloser(strings.NewReader("payload")),
+			}, nil
+		}),
+	}
+
+	api := NewAPI(
+		NewAPIOpts("token").
+			SetAPIUrl("https://example.test").
+			SetHTTPClient(client),
+	)
+	defer func() {
+		if err := api.CloseApi(); err != nil {
+			t.Fatalf("CloseApi returned error: %v", err)
+		}
+	}()
+
+	data, err := api.GetFileByLink("files/report.txt")
+	if err != nil {
+		t.Fatalf("GetFileByLink returned error: %v", err)
+	}
+	if string(data) != "payload" {
+		t.Fatalf("unexpected payload: %q", string(data))
+	}
+	if gotPath != "/file/bottoken/files/report.txt" {
+		t.Fatalf("unexpected request path: %s", gotPath)
+	}
+}
+
+func TestGetFileByLinkReturnsHTTPStatusError(t *testing.T) {
+	client := &http.Client{
+		Transport: roundTripFunc(func(req *http.Request) (*http.Response, error) {
+			return &http.Response{
+				StatusCode: http.StatusNotFound,
+				Body:       io.NopCloser(strings.NewReader("missing\n")),
+			}, nil
+		}),
+	}
+
+	api := NewAPI(
+		NewAPIOpts("token").
+			SetAPIUrl("https://example.test").
+			SetHTTPClient(client),
+	)
+	defer func() {
+		if err := api.CloseApi(); err != nil {
+			t.Fatalf("CloseApi returned error: %v", err)
+		}
+	}()
+
+	_, err := api.GetFileByLink("files/report.txt")
+	if err == nil {
+		t.Fatal("expected error for non-2xx response")
+	}
+}
+
+func TestGetUpdatesOmitsAllowedUpdatesWhenEmpty(t *testing.T) {
+	var gotBody map[string]any
+
+	client := &http.Client{
+		Transport: roundTripFunc(func(req *http.Request) (*http.Response, error) {
+			body, err := io.ReadAll(req.Body)
+			if err != nil {
+				t.Fatalf("failed to read request body: %v", err)
+			}
+			if err := json.Unmarshal(body, &gotBody); err != nil {
+				t.Fatalf("failed to decode request body: %v", err)
+			}
+			return &http.Response{
+				StatusCode: http.StatusOK,
+				Header:     http.Header{"Content-Type": []string{"application/json"}},
+				Body:       io.NopCloser(strings.NewReader(`{"ok":true,"result":[]}`)),
+			}, nil
+		}),
+	}
+
+	api := NewAPI(
+		NewAPIOpts("token").
+			SetAPIUrl("https://example.test").
+			SetHTTPClient(client),
+	)
+	defer func() {
+		if err := api.CloseApi(); err != nil {
+			t.Fatalf("CloseApi returned error: %v", err)
+		}
+	}()
+
+	updates, err := api.GetUpdates(UpdateParams{})
+	if err != nil {
+		t.Fatalf("GetUpdates returned error: %v", err)
+	}
+	if len(updates) != 0 {
+		t.Fatalf("expected no updates, got %d", len(updates))
+	}
+	if _, exists := gotBody["allowed_updates"]; exists {
+		t.Fatalf("expected allowed_updates to be omitted, got %v", gotBody["allowed_updates"])
+	}
+}

tgapi/types.go

@@ -1,5 +1,7 @@
 package tgapi
 
+import "encoding/json"
+
 // UpdateType represents the type of incoming update.
 type UpdateType string
 
@@ -23,8 +25,10 @@ const (
 	UpdateTypeBusinessMessage UpdateType = "business_message"
 	// UpdateTypeEditedBusinessMessage is an edited business message update.
 	UpdateTypeEditedBusinessMessage UpdateType = "edited_business_message"
-	// UpdateTypeDeletedBusinessMessage is a deleted business message update.
+	// UpdateTypeDeletedBusinessMessages is a deleted business messages update.
-	UpdateTypeDeletedBusinessMessage UpdateType = "deleted_business_message"
+	UpdateTypeDeletedBusinessMessages UpdateType = "deleted_business_messages"
+	// UpdateTypeDeletedBusinessMessage is kept as a backward-compatible alias.
+	UpdateTypeDeletedBusinessMessage UpdateType = UpdateTypeDeletedBusinessMessages
 
 	// UpdateTypeInlineQuery is an inline query update.
 	UpdateTypeInlineQuery UpdateType = "inline_query"
@@ -66,14 +70,15 @@ type Update struct {
 	BusinessConnection      *BusinessConnection          `json:"business_connection,omitempty"`
 	BusinessMessage         *Message                     `json:"business_message,omitempty"`
 	EditedBusinessMessage   *Message                     `json:"edited_business_message,omitempty"`
-	DeletedBusinessMessage *Message                     `json:"deleted_business_messages,omitempty"`
+	DeletedBusinessMessages *BusinessMessagesDeleted     `json:"deleted_business_messages,omitempty"`
+	DeletedBusinessMessage  *BusinessMessagesDeleted     `json:"-"`
 	MessageReaction         *MessageReactionUpdated      `json:"message_reaction,omitempty"`
 	MessageReactionCount    *MessageReactionCountUpdated `json:"message_reaction_count,omitempty"`
 
 	InlineQuery        *InlineQuery        `json:"inline_query,omitempty"`
 	ChosenInlineResult *ChosenInlineResult `json:"chosen_inline_result,omitempty"`
 	CallbackQuery      *CallbackQuery      `json:"callback_query,omitempty"`
-	ShippingQuery      ShippingQuery       `json:"shipping_query,omitempty"`
+	ShippingQuery      *ShippingQuery      `json:"shipping_query,omitempty"`
 	PreCheckoutQuery   *PreCheckoutQuery   `json:"pre_checkout_query,omitempty"`
 	PurchasedPaidMedia *PaidMediaPurchased `json:"purchased_paid_media,omitempty"`
 
@@ -86,6 +91,35 @@ type Update struct {
 	RemovedChatBoost *ChatBoostRemoved  `json:"removed_chat_boost,omitempty"`
 }
 
+func (u *Update) syncDeletedBusinessMessages() {
+	if u.DeletedBusinessMessages != nil {
+		u.DeletedBusinessMessage = u.DeletedBusinessMessages
+		return
+	}
+	if u.DeletedBusinessMessage != nil {
+		u.DeletedBusinessMessages = u.DeletedBusinessMessage
+	}
+}
+
+// UnmarshalJSON keeps the deprecated DeletedBusinessMessage alias in sync.
+func (u *Update) UnmarshalJSON(data []byte) error {
+	type alias Update
+	var aux alias
+	if err := json.Unmarshal(data, &aux); err != nil {
+		return err
+	}
+	*u = Update(aux)
+	u.syncDeletedBusinessMessages()
+	return nil
+}
+
+// MarshalJSON emits the canonical deleted_business_messages field.
+func (u Update) MarshalJSON() ([]byte, error) {
+	u.syncDeletedBusinessMessages()
+	type alias Update
+	return json.Marshal(alias(u))
+}
+
 // InlineQuery represents an incoming inline query.
 // See https://core.telegram.org/bots/api#inlinequery
 type InlineQuery struct {

tgapi/types_test.go

@@ -0,0 +1,69 @@
+package tgapi
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+)
+
+func TestUpdateDeletedBusinessMessagesUnmarshalSetsAlias(t *testing.T) {
+	var update Update
+	err := json.Unmarshal([]byte(`{
+		"update_id": 1,
+		"deleted_business_messages": {
+			"business_connection_id": "conn",
+			"chat": {"id": 42, "type": "private"},
+			"message_ids": [3, 5]
+		}
+	}`), &update)
+	if err != nil {
+		t.Fatalf("Unmarshal returned error: %v", err)
+	}
+
+	if update.DeletedBusinessMessages == nil {
+		t.Fatal("expected DeletedBusinessMessages to be populated")
+	}
+	if update.DeletedBusinessMessage == nil {
+		t.Fatal("expected deprecated DeletedBusinessMessage alias to be populated")
+	}
+	if update.DeletedBusinessMessages != update.DeletedBusinessMessage {
+		t.Fatal("expected deleted business message fields to share the same payload")
+	}
+	if got := update.DeletedBusinessMessages.MessageIDs; len(got) != 2 || got[0] != 3 || got[1] != 5 {
+		t.Fatalf("unexpected message ids: %v", got)
+	}
+}
+
+func TestUpdateMarshalUsesCanonicalDeletedBusinessMessagesField(t *testing.T) {
+	update := Update{
+		UpdateID: 1,
+		DeletedBusinessMessage: &BusinessMessagesDeleted{
+			BusinessConnectionID: "conn",
+			Chat:                 Chat{ID: 42, Type: string(ChatTypePrivate)},
+			MessageIDs:           []int{7},
+		},
+	}
+
+	data, err := json.Marshal(update)
+	if err != nil {
+		t.Fatalf("Marshal returned error: %v", err)
+	}
+
+	got := string(data)
+	if !strings.Contains(got, `"deleted_business_messages"`) {
+		t.Fatalf("expected canonical deleted_business_messages field, got %s", got)
+	}
+	if strings.Contains(got, `"deleted_business_message"`) {
+		t.Fatalf("unexpected singular deleted_business_message field, got %s", got)
+	}
+}
+
+func TestUpdateShippingQueryIsNilWhenAbsent(t *testing.T) {
+	var update Update
+	if err := json.Unmarshal([]byte(`{"update_id":1}`), &update); err != nil {
+		t.Fatalf("Unmarshal returned error: %v", err)
+	}
+	if update.ShippingQuery != nil {
+		t.Fatalf("expected ShippingQuery to be nil, got %+v", update.ShippingQuery)
+	}
+}

tgapi/uploader_api.go

@@ -126,7 +126,6 @@ func (r UploaderRequest[R, P]) doRequest(ctx context.Context, up *Uploader) (R,
 		req.Header.Set("Content-Type", contentType)
 		req.Header.Set("Accept", "application/json")
 		req.Header.Set("User-Agent", fmt.Sprintf("Laniakea/%s", utils.VersionString))
-		req.Header.Set("Accept-Encoding", "gzip")
 		req.ContentLength = int64(buf.Len())
 
 		up.logger.Debugln("UPLOADER REQ", r.method)

tgapi/uploader_api_test.go

@@ -0,0 +1,138 @@
+package tgapi
+
+import (
+	"fmt"
+	"io"
+	"mime"
+	"mime/multipart"
+	"net/http"
+	"strings"
+	"testing"
+)
+
+func TestUploaderEncodesJSONFieldsAndLeavesAcceptEncodingToHTTPTransport(t *testing.T) {
+	var (
+		gotPath           string
+		gotAcceptEncoding string
+		gotFields         map[string]string
+		gotFileName       string
+		gotFileData       []byte
+		roundTripErr      error
+	)
+
+	client := &http.Client{
+		Transport: roundTripFunc(func(req *http.Request) (*http.Response, error) {
+			gotPath = req.URL.Path
+			gotAcceptEncoding = req.Header.Get("Accept-Encoding")
+
+			gotFields, gotFileName, gotFileData, roundTripErr = readMultipartRequest(req)
+			if roundTripErr != nil {
+				roundTripErr = fmt.Errorf("readMultipartRequest: %w", roundTripErr)
+			}
+
+			return &http.Response{
+				StatusCode: http.StatusOK,
+				Header:     http.Header{"Content-Type": []string{"application/json"}},
+				Body:       io.NopCloser(strings.NewReader(`{"ok":true,"result":{"message_id":5,"date":1}}`)),
+			}, nil
+		}),
+	}
+
+	api := NewAPI(
+		NewAPIOpts("token").
+			SetAPIUrl("https://example.test").
+			SetHTTPClient(client),
+	)
+	defer func() {
+		if err := api.CloseApi(); err != nil {
+			t.Fatalf("CloseApi returned error: %v", err)
+		}
+	}()
+
+	uploader := NewUploader(api)
+	defer func() {
+		if err := uploader.Close(); err != nil {
+			t.Fatalf("Close returned error: %v", err)
+		}
+	}()
+
+	msg, err := uploader.SendPhoto(
+		UploadPhotoP{
+			ChatID: 42,
+			CaptionEntities: []MessageEntity{{
+				Type:   MessageEntityBold,
+				Offset: 0,
+				Length: 4,
+			}},
+			ReplyMarkup: &ReplyMarkup{
+				InlineKeyboard: [][]InlineKeyboardButton{{
+					{Text: "A", CallbackData: "b"},
+				}},
+			},
+		},
+		NewUploaderFile("photo.jpg", []byte("img")),
+	)
+	if err != nil {
+		t.Fatalf("SendPhoto returned error: %v", err)
+	}
+	if msg.MessageID != 5 {
+		t.Fatalf("unexpected message id: %d", msg.MessageID)
+	}
+	if roundTripErr != nil {
+		t.Fatalf("multipart parse failed: %v", roundTripErr)
+	}
+	if gotPath != "/bottoken/sendPhoto" {
+		t.Fatalf("unexpected request path: %s", gotPath)
+	}
+	if gotAcceptEncoding != "" {
+		t.Fatalf("expected empty Accept-Encoding header, got %q", gotAcceptEncoding)
+	}
+	if got := gotFields["chat_id"]; got != "42" {
+		t.Fatalf("chat_id mismatch: %q", got)
+	}
+	if got := gotFields["caption_entities"]; got != `[{"type":"bold","offset":0,"length":4}]` {
+		t.Fatalf("caption_entities mismatch: %q", got)
+	}
+	if got := gotFields["reply_markup"]; got != `{"inline_keyboard":[[{"text":"A","callback_data":"b"}]]}` {
+		t.Fatalf("reply_markup mismatch: %q", got)
+	}
+	if gotFileName != "photo.jpg" {
+		t.Fatalf("unexpected file name: %q", gotFileName)
+	}
+	if string(gotFileData) != "img" {
+		t.Fatalf("unexpected file content: %q", string(gotFileData))
+	}
+}
+
+func readMultipartRequest(req *http.Request) (map[string]string, string, []byte, error) {
+	_, params, err := mime.ParseMediaType(req.Header.Get("Content-Type"))
+	if err != nil {
+		return nil, "", nil, err
+	}
+	reader := multipart.NewReader(req.Body, params["boundary"])
+
+	fields := make(map[string]string)
+	var fileName string
+	var fileData []byte
+	for {
+		part, err := reader.NextPart()
+		if err == io.EOF {
+			return fields, fileName, fileData, nil
+		}
+		if err != nil {
+			return nil, "", nil, err
+		}
+
+		data, err := io.ReadAll(part)
+		if err != nil {
+			return nil, "", nil, err
+		}
+
+		if part.FileName() != "" {
+			fileName = part.FileName()
+			fileData = data
+			continue
+		}
+		fields[part.FormName()] = string(data)
+	}
+}

utils/multipart.go

@@ -1,6 +1,7 @@
 package utils
 
 import (
+	"encoding/json"
 	"fmt"
 	"io"
 	"mime/multipart"
@@ -12,12 +13,8 @@ import (
 
 // Encode writes struct fields into multipart form-data using json tags as field names.
 func Encode[T any](w *multipart.Writer, req T) error {
-	v := reflect.ValueOf(req)
+	v := unwrapMultipartValue(reflect.ValueOf(req))
-	if v.Kind() == reflect.Ptr {
+	if !v.IsValid() || v.Kind() != reflect.Struct {
-		v = v.Elem()
-	}
-
-	if v.Kind() != reflect.Struct {
 		return fmt.Errorf("req must be a struct")
 	}
 
@@ -33,6 +30,9 @@ func Encode[T any](w *multipart.Writer, req T) error {
 
 		parts := strings.Split(jsonTag, ",")
 		fieldName := parts[0]
+		if fieldName == "" {
+			fieldName = fieldType.Name
+		}
 		if fieldName == "-" {
 			continue
 		}
@@ -43,96 +43,73 @@ func Encode[T any](w *multipart.Writer, req T) error {
 			continue
 		}
 
-		var (
+		if err := writeMultipartField(w, fieldName, fieldType.Tag.Get("filename"), field); err != nil {
-			fw  io.Writer
-			err error
-		)
-
-		switch field.Kind() {
-		case reflect.String:
-			fw, err = w.CreateFormField(fieldName)
-			if err == nil {
-				_, err = fw.Write([]byte(field.String()))
-			}
-		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-			fw, err = w.CreateFormField(fieldName)
-			if err == nil {
-				_, err = fw.Write([]byte(strconv.FormatInt(field.Int(), 10)))
-			}
-		case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
-			fw, err = w.CreateFormField(fieldName)
-			if err == nil {
-				_, err = fw.Write([]byte(strconv.FormatUint(field.Uint(), 10)))
-			}
-		case reflect.Float32:
-			fw, err = w.CreateFormField(fieldName)
-			if err == nil {
-				_, err = fw.Write([]byte(strconv.FormatFloat(field.Float(), 'f', -1, 32)))
-			}
-		case reflect.Float64:
-			fw, err = w.CreateFormField(fieldName)
-			if err == nil {
-				_, err = fw.Write([]byte(strconv.FormatFloat(field.Float(), 'f', -1, 64)))
-			}
-
-		case reflect.Bool:
-			fw, err = w.CreateFormField(fieldName)
-			if err == nil {
-				_, err = fw.Write([]byte(strconv.FormatBool(field.Bool())))
-			}
-		case reflect.Slice:
-			if field.Type().Elem().Kind() == reflect.Uint8 && !field.IsNil() {
-				// Handle []byte as file upload (e.g., thumbnail)
-				filename := fieldType.Tag.Get("filename")
-				if filename == "" {
-					filename = fieldName
-				}
-				fw, err = w.CreateFormFile(fieldName, filename)
-				if err == nil {
-					_, err = fw.Write(field.Bytes())
-				}
-			} else if !field.IsNil() {
-				// Handle []string, []int, etc. — send as multiple fields with same name
-				for j := 0; j < field.Len(); j++ {
-					elem := field.Index(j)
-					fw, err = w.CreateFormField(fieldName)
-					if err != nil {
-						break
-					}
-					switch elem.Kind() {
-					case reflect.String:
-						_, err = fw.Write([]byte(elem.String()))
-					case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
-						_, err = fw.Write([]byte(strconv.FormatInt(elem.Int(), 10)))
-					case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
-						_, err = fw.Write([]byte(strconv.FormatUint(elem.Uint(), 10)))
-					case reflect.Bool:
-						_, err = fw.Write([]byte(strconv.FormatBool(elem.Bool())))
-					case reflect.Float32:
-						_, err = fw.Write([]byte(strconv.FormatFloat(elem.Float(), 'f', -1, 32)))
-					case reflect.Float64:
-						_, err = fw.Write([]byte(strconv.FormatFloat(elem.Float(), 'f', -1, 64)))
-					default:
-						continue
-					}
-					if err != nil {
-						break
-					}
-				}
-			}
-
-		case reflect.Struct:
-			// Don't serialize structs as JSON — flatten them!
-			// Telegram doesn't support nested JSON in form-data.
-			// If you need nested data, use separate fields (e.g., ParseMode, CaptionEntities)
-			// This is a design choice — you should avoid nested structs in params.
-			return fmt.Errorf("nested structs are not supported in params — use flat fields")
-		}
-
-		if err != nil {
 			return err
 		}
 	}
 
 	return nil
 }
+
+func unwrapMultipartValue(v reflect.Value) reflect.Value {
+	for v.IsValid() && (v.Kind() == reflect.Pointer || v.Kind() == reflect.Interface) {
+		if v.IsNil() {
+			return reflect.Value{}
+		}
+		v = v.Elem()
+	}
+	return v
+}
+
+func writeMultipartField(w *multipart.Writer, fieldName, filename string, field reflect.Value) error {
+	value := unwrapMultipartValue(field)
+	if !value.IsValid() {
+		return nil
+	}
+
+	switch value.Kind() {
+	case reflect.String:
+		return writeMultipartValue(w, fieldName, []byte(value.String()))
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return writeMultipartValue(w, fieldName, []byte(strconv.FormatInt(value.Int(), 10)))
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		return writeMultipartValue(w, fieldName, []byte(strconv.FormatUint(value.Uint(), 10)))
+	case reflect.Float32:
+		return writeMultipartValue(w, fieldName, []byte(strconv.FormatFloat(value.Float(), 'f', -1, 32)))
+	case reflect.Float64:
+		return writeMultipartValue(w, fieldName, []byte(strconv.FormatFloat(value.Float(), 'f', -1, 64)))
+	case reflect.Bool:
+		return writeMultipartValue(w, fieldName, []byte(strconv.FormatBool(value.Bool())))
+	case reflect.Slice:
+		if value.Type().Elem().Kind() == reflect.Uint8 {
+			if filename == "" {
+				filename = fieldName
+			}
+			fw, err := w.CreateFormFile(fieldName, filename)
+			if err != nil {
+				return err
+			}
+			_, err = fw.Write(value.Bytes())
+			return err
+		}
+	}
+
+	// Telegram expects nested objects and arrays in multipart requests as JSON strings.
+	data, err := json.Marshal(value.Interface())
+	if err != nil {
+		return err
+	}
+	if string(data) == "null" {
+		return nil
+	}
+	return writeMultipartValue(w, fieldName, data)
+}
+
+func writeMultipartValue(w *multipart.Writer, fieldName string, value []byte) error {
+	fw, err := w.CreateFormField(fieldName)
+	if err != nil {
+		return err
+	}
+	_, err = io.Copy(fw, strings.NewReader(string(value)))
+	return err
+}

utils/multipart_test.go

@@ -0,0 +1,85 @@
+package utils_test
+
+import (
+	"bytes"
+	"io"
+	"mime/multipart"
+	"testing"
+
+	"git.nix13.pw/scuroneko/laniakea/tgapi"
+	"git.nix13.pw/scuroneko/laniakea/utils"
+)
+
+type multipartEncodeParams struct {
+	ChatID          int64                  `json:"chat_id"`
+	MessageThreadID *int                   `json:"message_thread_id,omitempty"`
+	ReplyMarkup     *tgapi.ReplyMarkup     `json:"reply_markup,omitempty"`
+	CaptionEntities []tgapi.MessageEntity  `json:"caption_entities,omitempty"`
+	ReplyParameters *tgapi.ReplyParameters `json:"reply_parameters,omitempty"`
+}
+
+func TestEncodeMultipartJSONFields(t *testing.T) {
+	threadID := 7
+	params := multipartEncodeParams{
+		ChatID:          42,
+		MessageThreadID: &threadID,
+		ReplyMarkup: &tgapi.ReplyMarkup{
+			InlineKeyboard: [][]tgapi.InlineKeyboardButton{{
+				{Text: "A", CallbackData: "b"},
+			}},
+		},
+		CaptionEntities: []tgapi.MessageEntity{{
+			Type:   tgapi.MessageEntityBold,
+			Offset: 0,
+			Length: 4,
+		}},
+	}
+
+	body := bytes.NewBuffer(nil)
+	writer := multipart.NewWriter(body)
+	if err := utils.Encode(writer, params); err != nil {
+		t.Fatalf("Encode returned error: %v", err)
+	}
+	if err := writer.Close(); err != nil {
+		t.Fatalf("writer.Close returned error: %v", err)
+	}
+
+	got := readMultipartFields(t, body.Bytes(), writer.Boundary())
+	if got["chat_id"] != "42" {
+		t.Fatalf("chat_id mismatch: %q", got["chat_id"])
+	}
+	if got["message_thread_id"] != "7" {
+		t.Fatalf("message_thread_id mismatch: %q", got["message_thread_id"])
+	}
+	if got["reply_markup"] != `{"inline_keyboard":[[{"text":"A","callback_data":"b"}]]}` {
+		t.Fatalf("reply_markup mismatch: %q", got["reply_markup"])
+	}
+	if got["caption_entities"] != `[{"type":"bold","offset":0,"length":4}]` {
+		t.Fatalf("caption_entities mismatch: %q", got["caption_entities"])
+	}
+	if _, ok := got["reply_parameters"]; ok {
+		t.Fatalf("reply_parameters should be omitted when nil")
+	}
+}
+
+func readMultipartFields(t *testing.T, body []byte, boundary string) map[string]string {
+	t.Helper()
+
+	reader := multipart.NewReader(bytes.NewReader(body), boundary)
+	fields := make(map[string]string)
+	for {
+		part, err := reader.NextPart()
+		if err == io.EOF {
+			return fields
+		}
+		if err != nil {
+			t.Fatalf("NextPart returned error: %v", err)
+		}
+
+		data, err := io.ReadAll(part)
+		if err != nil {
+			t.Fatalf("ReadAll returned error: %v", err)
+		}
+		fields[part.FormName()] = string(data)
+	}
+}