feat(sointu, tracker,...): restructure domain & tracker models

send targets are now by ID and Song has "Score" part, which is the notes for it. also, moved the model part separate of the actual gioui dependend stuff.

sorry to my future self about the code bomb; ended up too far and did not find an easy way to rewrite the history to make the steps smaller, so in the end, just squashed everything.

tracker/gioui/label.go

@@ -0,0 +1,52 @@
+package gioui
+
+import (
+	"image"
+	"image/color"
+
+	"gioui.org/f32"
+	"gioui.org/layout"
+	"gioui.org/op"
+	"gioui.org/op/paint"
+	"gioui.org/text"
+	"gioui.org/unit"
+	"gioui.org/widget"
+)
+
+type LabelStyle struct {
+	Text       string
+	Color      color.NRGBA
+	ShadeColor color.NRGBA
+	Alignment  layout.Direction
+	Font       text.Font
+	FontSize   unit.Value
+}
+
+func (l LabelStyle) Layout(gtx layout.Context) layout.Dimensions {
+	return layout.Stack{Alignment: l.Alignment}.Layout(gtx,
+		layout.Stacked(func(gtx layout.Context) layout.Dimensions {
+			defer op.Save(gtx.Ops).Load()
+			paint.ColorOp{Color: l.ShadeColor}.Add(gtx.Ops)
+			op.Offset(f32.Pt(2, 2)).Add(gtx.Ops)
+			dims := widget.Label{
+				Alignment: text.Start,
+				MaxLines:  1,
+			}.Layout(gtx, textShaper, l.Font, l.FontSize, l.Text)
+			return layout.Dimensions{
+				Size:     dims.Size.Add(image.Pt(2, 2)),
+				Baseline: dims.Baseline,
+			}
+		}),
+		layout.Stacked(func(gtx layout.Context) layout.Dimensions {
+			paint.ColorOp{Color: l.Color}.Add(gtx.Ops)
+			return widget.Label{
+				Alignment: text.Start,
+				MaxLines:  1,
+			}.Layout(gtx, textShaper, l.Font, l.FontSize, l.Text)
+		}),
+	)
+}
+
+func Label(str string, color color.NRGBA) layout.Widget {
+	return LabelStyle{Text: str, Color: color, ShadeColor: black, Font: labelDefaultFont, FontSize: labelDefaultFontSize, Alignment: layout.W}.Layout
+}