ux stuff

common/elements/v1/element.go

@@ -0,0 +1,92 @@
+package elements
+
+import (
+	"context"
+
+	"github.com/hajimehoshi/ebiten/v2"
+)
+
+type MouseState struct {
+	X, Y                      int32
+	LeftDown, RightDown       bool
+	LeftChanged, RightChanged bool
+}
+
+const (
+	ContainerSizeKey = "container_size"
+	ZeroKey          = "zero"
+)
+
+type Clickable interface {
+	Element
+	HandleClick(ctx context.Context, s MouseState) error
+}
+
+type Mouseable interface {
+	Element
+	HandleMouseEnter(ctx context.Context, s MouseState) error
+	HandleMouseLeave(ctx context.Context, s MouseState) error
+	HandleMouseMove(ctx context.Context, s MouseState) error
+	HandleMouseDown(ctx context.Context, s MouseState) error
+	HandleMouseUp(ctx context.Context, s MouseState) error
+}
+
+type Element interface {
+	Draw(ctx context.Context, image *ebiten.Image) error
+}
+
+func SetZero(ctx context.Context, x, y float32) context.Context {
+	return context.WithValue(ctx, ZeroKey, [2]float32{x, y})
+}
+
+func SetContainerSize(ctx context.Context, w, h float32) context.Context {
+	return context.WithValue(ctx, ContainerSizeKey, [2]float32{w, h})
+}
+
+func GetZero(ctx context.Context) (x, y float32) {
+	if v, ok := ctx.Value(ZeroKey).([2]float32); ok {
+		return v[0], v[1]
+	}
+	return 0, 0
+}
+
+func GetContainerSize(ctx context.Context) (w, h float32) {
+	if s, ok := ctx.Value(ContainerSizeKey).([2]float32); ok {
+		return s[0], s[1]
+	}
+	return 0, 0
+}
+
+type mouseHandler struct {
+	mouseState     MouseState
+	prevMouseState MouseState
+}
+
+func (b *mouseHandler) HandleMouseEnter(s MouseState) error {
+	b.mouseState = s
+	return nil
+}
+
+func (b *mouseHandler) HandleMouseLeave(s MouseState) error {
+	b.prevMouseState = b.mouseState
+	b.mouseState = MouseState{}
+	return nil
+}
+
+func (b *mouseHandler) HandleMouseMove(s MouseState) error {
+	b.prevMouseState = b.mouseState
+	b.mouseState = s
+	return nil
+}
+
+func (b *mouseHandler) HandleMouseDown(s MouseState) error {
+	b.prevMouseState = b.mouseState
+	b.mouseState = s
+	return nil
+}
+
+func (b *mouseHandler) HandleMouseUp(s MouseState) error {
+	b.prevMouseState = b.mouseState
+	b.mouseState = s
+	return nil
+}