Implemented synchronous reading from the client letting us read messages.

cmd/test/main.go

@@ -3,18 +3,24 @@ package main
 import (
 	"log"
 	"os"
+	"strings"
 
 	"github.com/mojosa-software/got/src/tx"
 )
 
-var navKeyboard = tx.NewKeyboard("nav").Row(
-	tx.NewButton().WithText("Inc/Dec").ScreenChange("inc/dec"),
-).Row(
-	tx.NewButton().WithText("Upper case").ScreenChange("upper-case"),
-	tx.NewButton().WithText("Lower case").ScreenChange("lower-case"),
-)
+var startScreenButton = tx.NewButton().
+	WithText("🏠 To the start screen").
+	ScreenChange("start")
 
-var incKeyboard = tx.NewKeyboard("inc/dec").Row(
+var beh = tx.NewBehaviour().
+	// The function will be called every time
+	// the bot is started.
+	OnStartFunc(func(c *tx.Context) {
+		c.V["counter"] = new(int)
+		c.ChangeScreen("start")
+	}).WithKeyboards(
+	// Increment/decrement keyboard.
+	tx.NewKeyboard("inc/dec").Row(
 		tx.NewButton().WithText("+").ActionFunc(func(c *tx.Context) {
 			counter := c.V["counter"].(*int)
 			*counter++
@@ -25,29 +31,48 @@ var incKeyboard = tx.NewKeyboard("inc/dec").Row(
 			*counter--
 			c.Sendf("%d", *counter)
 		}),
-)
-
-var startScreen = tx.NewScreen("start").
-	WithText("The bot started!").
-	Keyboard("nav")
-
-var incScreen = tx.NewScreen("inc/dec").
-	WithText("The screen shows how user separated data works").
-	IKeyboard("inc/dec").
-	Keyboard("nav")
-
-var beh = tx.NewBehaviour().
-	OnStartFunc(func(c *tx.Context) {
-		// The function will be called every time
-		// the bot is started.
-		c.V["counter"] = new(int)
-		c.ChangeScreen("start")
-	}).WithKeyboards(
-	navKeyboard,
-	incKeyboard,
+	).Row(
+		startScreenButton,
+	),
+	// The navigational keyboard.
+	tx.NewKeyboard("nav").Row(
+		tx.NewButton().WithText("Inc/Dec").ScreenChange("inc/dec"),
+	).Row(
+		tx.NewButton().WithText("Upper case").ScreenChange("upper-case"),
+		tx.NewButton().WithText("Lower case").ScreenChange("lower-case"),
+	),
+	// The keyboard to return to the start screen.
+	tx.NewKeyboard("nav-start").Row(
+		startScreenButton,
+	),
 ).WithScreens(
-	startScreen,
-	incScreen,
+	tx.NewScreen("start").
+		WithText("The bot started!").
+		Keyboard("nav"),
+	tx.NewScreen("inc/dec").
+		WithText(
+			"The screen shows how"+
+				"user separated data works"+
+				"by saving the counter for each of them",
+		).
+		Keyboard("inc/dec").
+		// The function will be called when reaching the screen.
+		ActionFunc(func(c *tx.Context) {
+			counter := c.V["counter"].(*int)
+			c.Sendf("Current counter value equals %d", *counter)
+		}),
+	tx.NewScreen("upper-case").
+		WithText("Type text and the bot will send you the upper case version to you").
+		Keyboard("nav-start").
+		ActionFunc(func(c *tx.Context) {
+			for {
+				s, err := c.ReadTextMessage()
+				if err == tx.NotAvailableErr {
+					break
+				}
+				c.Sendf("%s", strings.ToUpper(s))
+			}
+		}),
 )
 
 func main() {

src/tx/bot.go

@@ -61,6 +61,7 @@ func (bot *Bot) Run() error {
 					ctx := &Context{
 						B:       bot,
 						Session: session,
+						updates: make(chan *Update),
 					}
 
 					chn := make(chan *Update)

src/tx/context.go

@@ -11,16 +11,18 @@ import (
 type Context struct {
 	*Session
 	B         *Bot
+	updates   chan *Update
+	available bool
 }
 
 // Goroutie function to handle each user.
-func (ctx *Context) handleUpdateChan(updates chan *Update) {
-	bot := ctx.B
-	session := ctx.Session
-	bot.Start.Act(ctx)
+func (c *Context) handleUpdateChan(updates chan *Update) {
+	bot := c.B
+	session := c.Session
+	bot.Start.Act(c)
 	for u := range updates {
 		screen := bot.Screens[session.CurrentScreenId]
-
+		// The part is added to implement custom update handling.
 		if u.Message != nil {
 
 			kbd := bot.Keyboards[screen.KeyboardId]
@@ -28,12 +30,26 @@ func (ctx *Context) handleUpdateChan(updates chan *Update) {
 			text := u.Message.Text
 			btn, ok := btns[text]
 
-			// Skipping wrong text messages.
-			if !ok {
+			/*if ok {
+				c.available = false
+				btn.Action.Act(c)
+				c.available = true
+				continue
+			}*/
+
+			// Sending wrong messages to
+			// the currently reading goroutine.
+			if !ok && c.ReadingUpdate {
+				c.updates <- u
 				continue
 			}
 
-			btn.Action.Act(ctx)
+			if !ok {
+			}
+
+			if ok {
+				c.run(btn.Action)
+			}
 		} else if u.CallbackQuery != nil {
 			cb := apix.NewCallback(u.CallbackQuery.ID, u.CallbackQuery.Data)
 			data := u.CallbackQuery.Data
@@ -45,11 +61,20 @@ func (ctx *Context) handleUpdateChan(updates chan *Update) {
 			kbd := bot.Keyboards[screen.InlineKeyboardId]
 			btns := kbd.buttonMap()
 			btn := btns[data]
-			btn.Action.Act(ctx)
+			btn.Action.Act(c)
 		}
 	}
 }
 
+func (c *Context) run(a Action) {
+	c.available = true
+	go a.Act(c)
+}
+
+func (c *Context) Available() bool {
+	return c.available
+}
+
 // Changes screen of user to the Id one.
 func (c *Context) ChangeScreen(screenId ScreenId) error {
 	// Return if it will not change anything.
@@ -67,16 +92,55 @@ func (c *Context) ChangeScreen(screenId ScreenId) error {
 	c.Session.ChangeScreen(screenId)
 	c.KeyboardId = screen.KeyboardId
 
+	c.available = false
+	if screen.Action != nil {
+		c.run(screen.Action)
+	}
+
 	return nil
 }
 
+// Returns the next update ignoring current screen.
+func (c *Context) ReadUpdate() (*Update, error) {
+	var (
+		u *Update
+	)
+	c.ReadingUpdate = true
+	for {
+		select {
+		case u = <-c.updates:
+			c.ReadingUpdate = false
+			return u, nil
+		default:
+			if !c.available {
+				return nil, NotAvailableErr
+			}
+		}
+	}
+
+}
+
+// Returns the next text message that the user sends.
+func (c *Context) ReadTextMessage() (string, error) {
+	u, err := c.ReadUpdate()
+	if err != nil {
+		return "", err
+	}
+	if u.Message == nil {
+		return "", WrongUpdateType{}
+	}
+
+	return u.Message.Text, nil
+}
+
 // Sends to the user specified text.
-func (c *Context) Send(text string) error {
-	msg := apix.NewMessage(c.Id.ToTelegram(), text)
+func (c *Context) Send(v ...any) error {
+	msg := apix.NewMessage(c.Id.ToTelegram(), fmt.Sprint(v...))
 	_, err := c.B.Send(msg)
 	return err
 }
 
+// Sends the formatted with fmt.Sprintf message to the user.
 func (c *Context) Sendf(format string, v ...any) error {
 	return c.Send(fmt.Sprintf(format, v...))
 }

src/tx/errors.go

@@ -2,10 +2,23 @@ package tx
 
 import (
 	"errors"
+	"fmt"
 )
 
+type WrongUpdateType struct {
+	Type string
+}
+
 var (
 	ScreenNotExistErr   = errors.New("screen does not exist")
 	SessionNotExistErr  = errors.New("session does not exist")
 	KeyboardNotExistErr = errors.New("keyboard does not exist")
+	NotAvailableErr     = errors.New("the context is not available")
 )
+
+func (wut WrongUpdateType) Error() string {
+	if wut.Type == "" {
+		return "wrong update type"
+	}
+	return fmt.Sprintf("wrong update type '%s'", wut.Type)
+}

src/tx/screen.go

@@ -24,6 +24,9 @@ type Screen struct {
 
 	// Keyboard to be displayed on the screen.
 	KeyboardId KeyboardId
+
+	// Action called on the reaching the screen.
+	Action Action
 }
 
 // Map structure for the screens.
@@ -52,6 +55,15 @@ func (s *Screen) Keyboard(kbdId KeyboardId) *Screen {
 	return s
 }
 
+func (s *Screen) WithAction(a Action) *Screen {
+	s.Action = a
+	return s
+}
+
+func (s *Screen) ActionFunc(a ActionFunc) *Screen {
+	return s.WithAction(a)
+}
+
 // Rendering the screen text to string to be sent or printed.
 func (st ScreenText) String() string {
 	return string(st)

src/tx/session.go

@@ -19,9 +19,12 @@ type Session struct {
 	CurrentScreenId ScreenId
 	// ID of the previous screen.
 	PreviousScreenId ScreenId
-	// The currently showed on display keyboard.
+	// The currently showed on display keyboard inside Action.
 	KeyboardId KeyboardId
 
+	// Is true if currently reading the Update.
+	ReadingUpdate bool
+
 	// Custom data for each user.
 	V map[string]any
 }