Add overlay components 176-195; pixel Harbor and Kit.Cue

Dialogs on DialogBase with focusable panels that harbor parked focus,
popovers on PopoverBase, bubbles, drawers, sheets, a lightbox, an RPG
dialogue box, notifications, a pause menu and a dithered title card.
Kit.Cue moves from feedback to pixel.

overlay/notification.go

@@ -0,0 +1,113 @@
+package overlay
+
+import (
+	"log/slog"
+	"time"
+
+	"github.com/egoist/mygo/ui"
+
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/icon"
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/input"
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/pixel"
+	"git.zacharyzhang.com/ZacharyZhang-NY/8bitMyGoUI/text"
+)
+
+// Notification is a card in the queue Notifications shows.
+type Notification struct {
+	Icon        *pixel.Sprite
+	Title, Text string
+	// For is how long it shows; zero means five seconds.
+	For time.Duration
+	// id and shown are set as it first shows.
+	id    uint64
+	shown time.Time
+}
+
+type NotificationsOptions struct {
+	// Width is each card's in dots; zero means 180.
+	Width    int
+	Disabled bool
+}
+
+type NotificationsResult struct {
+	// Element holds the cards on screen.
+	Element *ui.Element
+	// Dismissed is the card × closed this frame, or nil.
+	Dismissed *Notification
+}
+
+type notesKey struct{}
+
+// Notifications stacks timed cards at the top right; × dismisses.
+func Notifications(c *ui.Context, queue *[]Notification, o NotificationsOptions) NotificationsResult {
+	k := pixel.K(c)
+	w := pixel.Or("Notifications Width", o.Width, 180)
+	now := k.Now()
+	kept := (*queue)[:0]
+	for _, n := range *queue {
+		if n.For < 0 {
+			panic("overlay: Notification For is negative")
+		}
+		life := n.For
+		if life == 0 {
+			life = 5 * time.Second
+		}
+		if n.shown.IsZero() || now.Sub(n.shown) < life {
+			kept = append(kept, n)
+		}
+	}
+	*queue = kept
+	shown := min(4, len(*queue))
+	last := ui.Local(c.Root(), notesKey{}, func() uint64 { return 0 })
+	for i := range shown {
+		if (*queue)[i].id == 0 {
+			*last++
+			(*queue)[i].id, (*queue)[i].shown = *last, now
+		}
+	}
+	if shown > 0 {
+		k.Tick(c, 4)
+	}
+	var res NotificationsResult
+	ui.Overlay(c, func() {
+		res.Element = ui.Column(c).Absolute().Right(k.D(8)).Top(k.D(8)).Width(k.D(w)).Gap(k.D(4)).AlignItems(ui.Stretch).Children(func() {
+			for i := range shown {
+				n := (*queue)[i]
+				ui.Row(c).Key(n.id).Padding(k.D(5), k.D(6)).Gap(k.D(6)).Role(ui.RoleStatus).Label(n.Title).Description(n.Text).Draw(func(p *ui.Painter, r ui.Rect) {
+					g := k.Canvas(p, r)
+					g.Frame(0, 0, g.W, g.H, pixel.Window, pixel.Face)
+				}).Children(func() {
+					art := n.Icon
+					if art == nil {
+						art = icon.Bell
+					}
+					ui.Box(c).Size(k.D(art.W), k.D(art.H)).Shrink(0).Draw(func(p *ui.Painter, r ui.Rect) {
+						k.Canvas(p, r).Sprite(0, 0, art, 0, pixel.Accent, 1)
+					})
+					ui.Column(c).Grow(1).Children(func() {
+						pixel.Text(c, n.Title, pixel.TextOptions{})
+						text.Paragraph(c, n.Text, text.ParagraphOptions{Slot: pixel.Faint})
+					})
+					if input.IconButton(c, icon.Close, k.Msg("close"), input.IconButtonOptions{Size: input.Small, Variant: input.Ghost, Disabled: o.Disabled}).Clicked {
+						res.Dismissed = &n
+					}
+				})
+			}
+		})
+	})
+	if res.Dismissed != nil {
+		*queue = dropNote(*queue, res.Dismissed.id)
+		slog.Debug("8bit: notification dismissed", "title", res.Dismissed.Title)
+	}
+	return res
+}
+
+// dropNote removes the card with id from q.
+func dropNote(q []Notification, id uint64) []Notification {
+	for i := range q {
+		if q[i].id == id {
+			return append(q[:i], q[i+1:]...)
+		}
+	}
+	return q
+}