Now can automatically set the commands on the user side.

cmd/test/main.go

@@ -26,7 +26,7 @@ func NewMutateMessageWidget(fn func(string) string) *MutateMessageWidget {
 	return ret
 }
 
-func (w *MutateMessageWidget) Serve(c *tg.Context, updates chan *tg.Update) {
+func (w *MutateMessageWidget) Serve(c *tg.Context, updates chan *tg.Update) error {
 	for u := range updates {
 		if u.Message == nil {
 			continue
@@ -34,6 +34,7 @@ func (w *MutateMessageWidget) Serve(c *tg.Context, updates chan *tg.Update) {
 		text := u.Message.Text
 		c.Sendf("%s", w.Mutate(text))
 	}
+	return nil
 }
 
 func ExtractSessionData(c *tg.Context) *SessionData {
@@ -173,7 +174,7 @@ var beh = tg.NewBehaviour().
 				),
 			),
 		),
-).WithCommands(
+	).WithCommands(
 		tg.NewCommand("start").
 			Desc("start or restart the bot or move to the start screen").
 			ActionFunc(func(c *tg.Context){
@@ -203,17 +204,17 @@ var beh = tg.NewBehaviour().
 		tg.NewCommand("botname").
 			Desc("get the bot name").
 			ActionFunc(func(c *tg.Context) {
-			bd := c.Bot.Value().(*BotData)
+				bd := c.Bot.Data.(*BotData)
 				c.Sendf("My name is %q", bd.Name)
 			}),
-)
+	)
 
 var gBeh = tg.NewGroupBehaviour().
 	InitFunc(func(c *tg.GC) {
 	}).
 	WithCommands(
 		tg.NewGroupCommand("hello").ActionFunc(func(c *tg.GC) {
-			c.Send("Hello, World!")
+			c.Sendf("Hello, World!")
 		}),
 		tg.NewGroupCommand("mycounter").ActionFunc(func(c *tg.GC) {
 			d := c.Session().Data.(*SessionData)
@@ -231,11 +232,15 @@ func main() {
 	bot = bot.
 		WithBehaviour(beh).
 		WithGroupBehaviour(gBeh).
-		WithValue(&BotData{
-			Name: "Jay",
-		}).
 		Debug(true)
 
+	bot.Data = &BotData{
+		Name: "Jay",
+	}
+
 	log.Printf("Authorized on account %s", bot.Api.Self.UserName)
-	bot.Run()
+	err = bot.Run()
+	if err != nil {
+		panic(err)
+	}
 }

tg/bot.go

@@ -2,6 +2,7 @@ package tg
 
 import (
 	"errors"
+	"sort"
 
 	//"fmt"
 
@@ -14,6 +15,8 @@ type User = tgbotapi.User
 
 // The wrapper around Telegram API.
 type Bot struct {
+	// Custom data value.
+	Data any
 	Api *tgbotapi.BotAPI
 	Me  *User
 	// Private bot behaviour.
@@ -24,7 +27,6 @@ type Bot struct {
 	channelBehaviour *ChannelBehaviour
 	sessions         SessionMap
 	groupSessions    GroupSessionMap
-	value            any
 	
 }
 
@@ -40,19 +42,6 @@ func NewBot(token string) (*Bot, error) {
 	}, nil
 }
 
-// Set the custom global value for the bot,
-// so it can be accessed from the callback
-// functions.
-func (bot *Bot) WithValue(v any) *Bot {
-	bot.value = v
-	return bot
-}
-
-// Get the global bot value.
-func (bot *Bot) Value() any {
-	return bot.value
-}
-
 func (bot *Bot) Debug(debug bool) *Bot {
 	bot.Api.Debug = debug
 	return bot
@@ -127,6 +116,40 @@ func (b *Bot) WithGroupSessions(sessions GroupSessionMap) *Bot {
 	return b
 }
 
+// Setting the command on the user side.
+func (bot *Bot) setCommands(
+	scope tgbotapi.BotCommandScope,
+	cmdMap map[CommandName] BotCommander,
+) {
+	// First the private commands.
+	names := []string{}
+	for name := range cmdMap {
+		names = append(names, string(name))
+	}
+	sort.Strings([]string(names))
+
+	cmds := []BotCommander{}
+	for _, name := range names {
+		cmds = append(
+			cmds,
+			cmdMap[CommandName(name)],
+		)
+	}
+
+	botCmds := []tgbotapi.BotCommand{}
+	for _, cmd := range cmds {
+		botCmds = append(botCmds, cmd.ToApi())
+	}
+
+	//tgbotapi.NewBotCommandScopeAllPrivateChats(),
+	cfg := tgbotapi.NewSetMyCommandsWithScope(
+		scope,
+		botCmds...,
+	)
+
+	bot.Api.Request(cfg)
+}
+
 // Run the bot with the Behaviour.
 func (bot *Bot) Run() error {
 	if bot.behaviour == nil &&
@@ -139,12 +162,28 @@ func (bot *Bot) Run() error {
 	handles := make(map[string]chan *Update)
 
 	if bot.behaviour != nil {
+		commanders := make(map[CommandName] BotCommander)
+		for k, v := range bot.behaviour.Commands {
+			commanders[k] = v
+		}
+		bot.setCommands(
+			tgbotapi.NewBotCommandScopeAllPrivateChats(),
+			commanders,
+		)
 		chn := make(chan *Update)
 		handles["private"] = chn
 		go bot.handlePrivate(chn)
 	}
 
 	if bot.groupBehaviour != nil {
+		commanders := make(map[CommandName] BotCommander)
+		for k, v := range bot.groupBehaviour.Commands {
+			commanders[k] = v
+		}
+		bot.setCommands(
+			tgbotapi.NewBotCommandScopeAllGroupChats(),
+			commanders,
+		)
 		chn := make(chan *Update)
 		handles["group"] = chn
 		handles["supergroup"] = chn

tg/command.go

@@ -3,10 +3,13 @@ package tg
 import (
 	//"flag"
 
-	apix "github.com/go-telegram-bot-api/telegram-bot-api/v5"
+	tgbotapi "github.com/go-telegram-bot-api/telegram-bot-api/v5"
 )
 
-type Message = apix.Message
+type BotCommander interface {
+	ToApi() tgbotapi.BotCommand
+}
+type Message = tgbotapi.Message
 type CommandName string
 
 type Command struct {
@@ -31,6 +34,13 @@ func (c *Command) ActionFunc(af ActionFunc) *Command {
 	return c.WithAction(af)
 }
 
+func (c *Command) ToApi() tgbotapi.BotCommand {
+	ret := tgbotapi.BotCommand{}
+	ret.Command = string(c.Name)
+	ret.Description = c.Description
+	return ret
+}
+
 func (c *Command) Desc(desc string) *Command {
 	c.Description = desc
 	return c
@@ -62,3 +72,10 @@ func (cmd *GroupCommand) Desc(desc string) *GroupCommand {
 	cmd.Description = desc
 	return cmd
 }
+
+func (c *GroupCommand) ToApi() tgbotapi.BotCommand {
+	ret := tgbotapi.BotCommand{}
+	ret.Command = string(c.Name)
+	ret.Description = c.Description
+	return ret
+}

tg/group.go

@@ -3,7 +3,7 @@ package tg
 import (
 	"fmt"
 
-	tgbotapi "github.com/go-telegram-bot-api/telegram-bot-api/v5"
+	//tgbotapi "github.com/go-telegram-bot-api/telegram-bot-api/v5"
 )
 
 // Customized actions for the group behaviour.
@@ -56,7 +56,12 @@ func (c *groupContext) handleUpdateChan(updates chan *Update) {
 				cmdName := CommandName(msg.Command())
 
 				// Skipping the commands sent not to us.
-				atName := msg.CommandWithAt()[len(cmdName)+1:]
+				withAt := msg.CommandWithAt()
+				if len(cmdName) == len(withAt) {
+					continue
+				}
+
+				atName := withAt[len(cmdName)+1:]
 				if c.Bot.Me.UserName != atName {
 					continue
 				}
@@ -74,16 +79,20 @@ func (c *groupContext) handleUpdateChan(updates chan *Update) {
 	}
 }
 
-func (c *groupContext) Sendf(format string, v ...any) error {
-	return c.Send(fmt.Sprintf(format, v...))
+func (c *groupContext) Sendf(
+	format string,
+	v ...any,
+) (*Message, error) {
+	msg, err := c.Send(NewMessage(
+		c.Session.Id, fmt.Sprintf(format, v...),
+	))
+	if err != nil {
+		return nil, err
+	}
+	return msg, err
 }
 
 // Sends into the chat specified values converted to strings.
-func (c *groupContext) Send(v ...any) error {
-	msg := tgbotapi.NewMessage(
-		c.Session.Id.ToApi(),
-		fmt.Sprint(v...),
-	)
-	_, err := c.Bot.Api.Send(msg)
-	return err
+func (c *groupContext) Send(v Sendable) (*Message, error) {
+	return c.Bot.Send(c.Session.Id, v)
 }

tg/private.go

@@ -11,7 +11,7 @@ type context struct {
 	// To reach the bot abilities inside callbacks.
 	Bot     *Bot
 	widgetUpdates chan *Update
-	CurScreen, PrevScreen *Screen
+	curScreen, prevScreen *Screen
 }
 
 // The type represents way to interact with user in
@@ -71,10 +71,7 @@ func (c *context) handleUpdateChan(updates chan *Update) {
 }
 
 func (c *context) run(a Action, u *Update) {
-	go a.Act(&Context{
-		context: c,
-		Update:  u,
-	})
+	a.Act(&Context{context: c, Update:  u})
 }
 
 func (c *context) Render(v Renderable) ([]*Message, error) {
@@ -149,8 +146,8 @@ func (c *Context) ChangeScreen(screenId ScreenId) error {
 	// Getting the screen and changing to
 	// then executing its widget.
 	screen := c.Bot.behaviour.Screens[screenId]
-	c.PrevScreen = c.CurScreen
-	c.CurScreen = screen
+	c.prevScreen = c.curScreen
+	c.curScreen = screen
 
 	// Making the new channel for the widget.
 	if c.widgetUpdates != nil {

tg/screen.go

@@ -6,10 +6,14 @@ type ScreenId string
 // Screen statement of the bot.
 // Mostly what buttons to show.
 type Screen struct {
+	// Unique identifer to change to the screen
+	// via Context.ChangeScreen method.
 	Id ScreenId
 	// The widget to run when reaching the screen.
 	Widget Widget
 
+	// Needs implementation later.
+	Dynamic DynamicWidget
 }
 
 // Map structure for the screens.
@@ -23,3 +27,8 @@ func NewScreen(id ScreenId, widget Widget) *Screen {
 	}
 }
 
+func (s *Screen) WithDynamic(dynamic DynamicWidget) *Screen {
+	s.Dynamic = dynamic
+	return s
+}
+

tg/widget.go

@@ -12,7 +12,20 @@ type Widget interface {
 	// widget MUST end its work.
 	// Mostly made by looping over the
 	// updates range.
-	Serve(*Context, chan *Update)
+	Serve(*Context, chan *Update) error
+}
+
+// Implementing the interface provides 
+type DynamicWidget interface {
+	MakeWidget() Widget
+}
+
+// The function that implements the Widget
+// interface.
+type WidgetFunc func(*Context, chan *Update)
+
+func (wf WidgetFunc) Serve(c *Context, updates chan *Update){
+	wf(c, updates)
 }
 
 // The basic widget to provide keyboard functionality
@@ -64,10 +77,10 @@ func (p *Page) WithSub(sub Widget) *Page {
 
 func (p *Page) Serve(
 	c *Context, updates chan *Update,
-) {
+) error {
 	msgs, err := c.Render(p)
 	if err != nil {
-		panic(err)
+		return err
 	}
 
 	// The inline message is always returned
@@ -128,7 +141,7 @@ func (p *Page) Serve(
 
 			_, err := c.Bot.Api.Request(cb)
 			if err != nil {
-				panic(err)
+				return err
 			}
 			kbd := p.Inline
 			if kbd == nil {
@@ -156,6 +169,7 @@ func (p *Page) Serve(
 			c.run(act, u)
 		} 
 	}
+	return nil
 }
 
 func (s *Page) Render(