Add cursor to nickname scene

pkg/client/engine.go

@@ -149,6 +149,8 @@ func setupChangeSceneHandler(currentScene *scenes.Scene, c *websocket.Conn) erro
 
 		*currentScene = scene
 
+		termbox.HideCursor()
+
 		if err := scene.Setup(changeScene, sendMessage); err != nil {
 			return err
 		}

pkg/client/scenes/draw_lib.go

@@ -39,6 +39,13 @@ func draw(anchor anchor, color color, text interface{}) {
 	}
 }
 
+// setCursor uses an anchor to determine the position of the cursor, so it can be used in
+// conjunction with draw to place the cursor.
+func setCursor(anchor anchor) {
+	x, y, _, _ := anchor()
+	termbox.SetCursor(x, y-1)
+}
+
 // anchor defines a position offset and direction that can be used for drawing.
 type anchor func() (positionX, positionY int, drawDirectionX, drawDirectionY float64)
 

pkg/client/scenes/nickname.go

@@ -61,12 +61,20 @@ func (n *Nickname) OnTerminalEvent(event termbox.Event) error {
 		n.nickname = n.nickname[:len(n.nickname)-1]
 	}
 
-	if len(n.nickname) >= maxNicknameLen {
-		return nil
+	var setLastChar func(rune)
+
+	if len(n.nickname) < maxNicknameLen {
+		setLastChar = func(r rune) {
+			n.nickname += string(r)
+		}
+	} else {
+		setLastChar = func(r rune) {
+			n.nickname = n.nickname[:maxNicknameLen-1] + string(r)
+		}
 	}
 
 	if event.Key == termbox.KeySpace {
-		n.nickname += " "
+		setLastChar(' ')
 		return nil
 	}
 
@@ -75,7 +83,7 @@ func (n *Nickname) OnTerminalEvent(event termbox.Event) error {
 		return nil
 	}
 
-	n.nickname += string(letter)
+	setLastChar(letter)
 
 	return nil
 }
@@ -101,6 +109,9 @@ func (n *Nickname) Draw() {
 	}
 
 	draw(offset(center, 0, 4), normal, sb.String())
+
+	cursorX := min(len(n.nickname), maxNicknameLen-1) - maxNicknameLen/2
+	setCursor(offset(center, cursorX, 4))
 }
 
 func (n *Nickname) load() error {