1 files changed, 61 insertions, 0 deletions
diff --git a/go/ui/timerBar.go b/go/ui/timerBar.go
new file mode 100644
index 00000000..2549f863
--- /dev/null
+++ b/go/ui/timerBar.go
@@ -0,0 +1,61 @@
+package ui
+
+import (
+	"image/color"
+	"time"
+
+	"github.com/hajimehoshi/ebiten/v2"
+)
+
+var (
+	TIMERBAR_DEFAULT_BACKGROUND = color.Black
+	TIMERBAR_DEFAULT_FOREGROUND = color.White
+)
+
+type TimerBar struct {
+	WidgetBase
+	fg       color.Color
+	bg       color.Color
+	start    time.Time
+	deadline time.Time
+}
+
+func NewTimerBar(x, y int, width, height int, timer time.Duration) *TimerBar {
+	tb := &TimerBar{
+		WidgetBase: NewWidgetBase(x, y, width, height),
+		bg:         TEXTBOX_DEFAULT_BACKGROUND,
+		fg:         TEXTBOX_DEFAULT_FOREGROUND,
+		start:      time.Now(),
+		deadline:   time.Now().Add(timer),
+	}
+	tb.renderImpl = func() *ebiten.Image { return tb.render() }
+	tb.EventHandlersMap["update"] = func() error {
+		if time.Now().Before(tb.deadline) {
+			tb.ForceRedraw()
+		}
+		return nil
+	}
+	return tb
+}
+
+func (tb *TimerBar) Bg(bg color.Color) *TimerBar {
+	tb.bg = bg
+	return tb
+}
+
+func (tb *TimerBar) Fg(fg color.Color) *TimerBar {
+	tb.fg = fg
+	return tb
+}
+
+func (tb *TimerBar) render() *ebiten.Image {
+	img := ebiten.NewImage(tb.Width, tb.Height)
+	img.Fill(tb.bg)
+	fraction := float64(time.Since(tb.start)) / float64(tb.deadline.Sub(tb.start))
+	barWidth := int(float64(tb.Width) * fraction)
+	bar := ebiten.NewImage(barWidth, tb.Height)
+	bar.Fill(tb.fg)
+	op := ebiten.DrawImageOptions{}
+	img.DrawImage(bar, &op)
+	return img
+}