init: pristine aerc 0.20.0 source

lib/ui/stack.go

@@ -0,0 +1,64 @@
+package ui
+
+import (
+	"fmt"
+
+	"git.sr.ht/~rjarry/aerc/config"
+	"git.sr.ht/~rockorager/vaxis"
+)
+
+type Stack struct {
+	children []Drawable
+	uiConfig *config.UIConfig
+}
+
+func NewStack(uiConfig *config.UIConfig) *Stack {
+	return &Stack{uiConfig: uiConfig}
+}
+
+func (stack *Stack) Children() []Drawable {
+	return stack.children
+}
+
+func (stack *Stack) Invalidate() {
+	Invalidate()
+}
+
+func (stack *Stack) Draw(ctx *Context) {
+	if len(stack.children) > 0 {
+		stack.Peek().Draw(ctx)
+	} else {
+		ctx.Fill(0, 0, ctx.Width(), ctx.Height(), ' ',
+			stack.uiConfig.GetStyle(config.STYLE_STACK))
+	}
+}
+
+func (stack *Stack) MouseEvent(localX int, localY int, event vaxis.Event) {
+	if len(stack.children) > 0 {
+		if element, ok := stack.Peek().(Mouseable); ok {
+			element.MouseEvent(localX, localY, event)
+		}
+	}
+}
+
+func (stack *Stack) Push(d Drawable) {
+	stack.children = append(stack.children, d)
+	stack.Invalidate()
+}
+
+func (stack *Stack) Pop() Drawable {
+	if len(stack.children) == 0 {
+		panic(fmt.Errorf("Tried to pop from an empty UI stack"))
+	}
+	d := stack.children[len(stack.children)-1]
+	stack.children = stack.children[:len(stack.children)-1]
+	stack.Invalidate()
+	return d
+}
+
+func (stack *Stack) Peek() Drawable {
+	if len(stack.children) == 0 {
+		panic(fmt.Errorf("Tried to peek from an empty stack"))
+	}
+	return stack.children[len(stack.children)-1]
+}