package behx

import (
	apix "github.com/go-telegram-bot-api/telegram-bot-api/v5"
)

// Unique identifier for the screen.
type ScreenId string

// Should be replaced with something that can be
// dinamicaly rendered. (WIP)
type ScreenText string

// Screen statement of the bot.
// Mostly what buttons to show.
type Screen struct {
	// Text to be sent to the user when changing to the screen.
	Text ScreenText
	
	// The keyboard to be sent in the message part.
	InlineKeyboardId KeyboardId
	
	// Keyboard to be displayed on the screen.
	KeyboardId KeyboardId
}

// Map structure for the screens.
type ScreenMap map[ScreenId] *Screen

// Returns the new screen with specified Text and Keyboard.
func NewScreen(text ScreenText, ikbd KeyboardId, kbd KeyboardId) *Screen {
	return &Screen {
		Text: text,
		InlineKeyboardId: ikbd,
		KeyboardId: kbd,
	}
}

// Rendering the screen text to string to be sent or printed.
func (st ScreenText) String() string {
	return string(st)
}

// Renders output of the screen only to the side of the user.
func (s *Screen) Render(c *Context) error {
	id := c.Id.ToTelegram()
	
	msg := apix.NewMessage(id, s.Text.String())
	
	if s.InlineKeyboardId != "" {
		kbd, ok := c.B.Keyboards[s.InlineKeyboardId]
		if !ok {
			return KeyboardNotExistErr
		}
		msg.ReplyMarkup = kbd.ToTelegramInline()
	}
	
	_, err := c.B.Send(msg)
	if err != nil {
		return err
	}
	
	msg = apix.NewMessage(id, ">")
	// Checking if we need to resend the keyboard.
	if s.KeyboardId != c.KeyboardId {
		// Remove keyboard by default.
		var tkbd any
		tkbd = apix.NewRemoveKeyboard(true)
		
		// Replace keyboard with the new one.
		if s.KeyboardId != "" {
			kbd, ok := c.B.Keyboards[s.KeyboardId]
			if !ok {
				return KeyboardNotExistErr
			}
			tkbd = kbd.ToTelegram()
		}
		
		msg.ReplyMarkup = tkbd
		if _, err := c.B.Send(msg) ; err != nil {
			return err
		}
	} 
	
	return nil
}