refactor: move ui code from game/state/handlers/menu.go to its own package in game/ui

game/ui/button.go

@@ -0,0 +1,33 @@
+package ui
+
+import (
+	"tetris/engine/render"
+
+	rl "github.com/gen2brain/raylib-go/raylib"
+)
+
+type Button struct {
+	Text   string
+	Action func()
+}
+
+func NewButton(text string, action func()) Button {
+	return Button{
+		Text:   text,
+		Action: action,
+	}
+}
+
+func (b Button) HandleInput() {
+	if rl.IsKeyPressed(rl.KeyEnter) {
+		b.Action()
+	}
+}
+
+func (b Button) Draw(x, y int32, selected bool) {
+	col := rl.White
+	if selected {
+		col = rl.Red
+	}
+	render.DrawTextCenter(x, y, 32, b.Text, col)
+}

game/ui/menu.go

@@ -0,0 +1,59 @@
+package ui
+
+import (
+	"tetris/assets"
+	"tetris/engine/audio"
+
+	rl "github.com/gen2brain/raylib-go/raylib"
+)
+
+type Menu struct {
+	selected int
+	entries  []Widget
+}
+
+func NewMenu(entries []Widget) Menu {
+	return Menu{
+		entries: entries,
+	}
+}
+
+func (menu Menu) Entries() []Widget {
+	return menu.entries
+}
+
+func (menu *Menu) Select(index int) {
+	menu.selected = min(index, len(menu.entries)-1)
+}
+
+func (menu Menu) Selected() Widget {
+	return menu.entries[menu.selected]
+}
+
+func (menu Menu) IsSelected(index int) bool {
+	return menu.selected == index
+}
+
+func (menu *Menu) Next() {
+	if menu.selected+1 < len(menu.entries) {
+		menu.selected = menu.selected + 1
+		audio.Play(assets.SFX_MENU_SELECT)
+	}
+}
+
+func (menu *Menu) Previous() {
+	if menu.selected-1 >= 0 {
+		menu.selected = menu.selected - 1
+		audio.Play(assets.SFX_MENU_SELECT)
+	}
+}
+
+func (menu *Menu) HandleInput() {
+	if rl.IsKeyPressed(rl.KeyDown) {
+		menu.Next()
+	} else if rl.IsKeyPressed(rl.KeyUp) {
+		menu.Previous()
+	} else {
+		menu.Selected().HandleInput()
+	}
+}

game/ui/widget.go

@@ -0,0 +1,6 @@
+package ui
+
+type Widget interface {
+	HandleInput()
+	Draw(x, y int32, selected bool)
+}