move more ui logic into Collection

* Generalize hover detection and move it into ui.Collection
* Implement transparencu for the prompt banner

1 files changed, 42 insertions, 2 deletions

diff --git a/go/ui/collection.go b/go/ui/collection.go
index ac53ba8c..d75e3267 100644
--- a/go/ui/collection.go
+++ b/go/ui/collection.go
@@ -1,12 +1,20 @@
 package ui
 
 import (
+	"log"
+
 	"github.com/hajimehoshi/ebiten/v2"
 	"github.com/hajimehoshi/ebiten/v2/inpututil"
 )
 
 type Collection struct {
-	widgets []Widget
+	Width, Height int
+	hoverDetector hoverDetector
+	widgets       []Widget
+}
+
+func (c *Collection) Layout() (int, int) {
+	return c.Width, c.Height
 }
 
 func (c *Collection) Widgets() []Widget {
@@ -17,10 +25,40 @@ func (c *Collection) Clear() {
 	c.widgets = []Widget{}
 }
 
+func (c *Collection) ResetHover() {
+	c.hoverDetector.reset(0, 0)
+}
+
 func (c *Collection) AddWidget(w Widget) {
+	if w == nil {
+		log.Panicf("Adding nil widget to collection")
+	}
 	c.widgets = append(c.widgets, w)
 }
 
+func (c *Collection) FindWidget(toFind Widget) int {
+	for i, w := range c.widgets {
+		if w != toFind {
+			continue
+		}
+		return i
+	}
+	return -1
+}
+
+func (c *Collection) RemoveWidget(widget Widget) {
+	idx := c.FindWidget(widget)
+	if idx != -1 {
+		c.RemoveWidgetAt(idx)
+	}
+}
+
+func (c *Collection) RemoveWidgetAt(idx int) {
+	nwidgets := len(c.widgets)
+	c.widgets[idx] = c.widgets[nwidgets-1]
+	c.widgets = c.widgets[:nwidgets-1]
+}
+
 func (c *Collection) Draw(screen *ebiten.Image) {
 	for _, w := range c.widgets {
 		w.Draw(screen)
@@ -39,6 +77,8 @@ func (c *Collection) Update() error {
 		break
 	}
 
+	c.hoverDetector.update(c, x, y, activeWidget)
+
 	if activeWidget == nil {
 		return nil
 	}
@@ -61,7 +101,7 @@ func (c *Collection) Update() error {
 	}
 
 	if inpututil.IsMouseButtonJustPressed(ebiten.MouseButtonLeft) {
-		if btn, ok := activeWidget.(Button); ok {
+		if btn, ok := activeWidget.(Clickable); ok {
 			btn.Click(x, y)
 		}
 	}