Add basic terminal user interface

tui/statusbar.go

@@ -0,0 +1,37 @@
+package tui
+
+import (
+	"github.com/gdamore/tcell/v2"
+	"github.com/rivo/tview"
+)
+
+// StatusBar represents a status bar of the user interface.
+//
+// status is a text view showing a status message.
+type StatusBar struct {
+	*tview.Flex
+	status *tview.TextView
+}
+
+// NewStatusBar creates a new one-line status bar of the user interface.
+func NewStatusBar() *StatusBar {
+	ui := StatusBar{
+		Flex: tview.NewFlex(),
+	}
+
+	statusLabel := tview.NewTextView().SetText("Status:")
+	statusLabel.SetTextColor(tcell.NewRGBColor(180, 180, 180))
+	ui.AddItem(statusLabel, 8, 0, false)
+
+	ui.status = tview.NewTextView()
+	ui.status.SetText("idle")
+	ui.status.SetTextColor(tcell.NewRGBColor(180, 180, 180))
+	ui.AddItem(ui.status, 0, 1, false)
+
+	return &ui
+}
+
+// SetStatus displays a status message.
+func (ui *StatusBar) SetStatus(text string) {
+	ui.status.SetText(text)
+}