refactor

pkg/clock/letter/image.go

@@ -0,0 +1,106 @@
+package letter
+
+import (
+	"embed"
+	"encoding/csv"
+	"image"
+	"image/color"
+	"image/draw"
+	"io"
+
+	"git.niplace.ru/XoxJlopeZi4BB/imageutils"
+)
+
+type Letter string
+
+//go:embed map.csv
+var fs embed.FS
+var mapFile = func() io.Reader {
+	f, err := fs.Open("map.csv")
+	if err != nil {
+		panic(err)
+	}
+	return f
+}()
+
+var Letters = func(r io.Reader) (m map[string]string) {
+	records, err := csv.NewReader(r).ReadAll()
+	if err != nil {
+		panic(err)
+	}
+	for _, v := range records {
+		if len(v) < 2 {
+			panic("csv file isn's key-value pair")
+		}
+		m[v[0]] = v[1]
+	}
+	return m
+}(mapFile)
+
+// implements image.Image interface.
+func (l Letter) ColorModel() color.Model {
+	return color.Alpha16Model
+}
+
+// implements image.Image interface.
+func (l Letter) Bounds() image.Rectangle {
+	return image.Rect(0, 0, 3, 3)
+}
+
+// implements image.Image interface.
+func (l Letter) At(x, y int) color.Color {
+	if len(l) != 9 {
+		panic("len(Letter) != 9")
+	}
+	target := l[x+y*3]
+	if target != '1' {
+		return color.Opaque
+	}
+	return color.Transparent
+}
+
+func Render(l Letter) image.Image {
+	img := image.NewRGBA(l.Bounds())
+	draw.Draw(img, l.Bounds(), image.White, image.ZP, draw.Src)
+	draw.Draw(img, l.Bounds(), l, image.ZP, draw.Over)
+	return img
+}
+
+type blank struct {
+	image.Image
+	color.Color
+	imageutils.Side
+}
+
+func (b blank) ColorModel() color.Model { return b.Image.ColorModel() }
+
+func (b blank) Bounds() image.Rectangle {
+	rect := image.Rectangle{}
+	switch b.Side {
+	case imageutils.Left:
+		fallthrough
+	case imageutils.Right:
+		rect = image.Rectangle{
+			image.ZP,
+			image.Point{
+				1, b.Image.Bounds().Dy(),
+			},
+		}
+	case imageutils.Up:
+		fallthrough
+	case imageutils.Down:
+		rect = image.Rectangle{
+			image.ZP,
+			image.Point{
+				b.Image.Bounds().Dx(), 1,
+			},
+		}
+	}
+	return rect
+}
+
+func (b blank) At(x, y int) color.Color { return b.Color }
+
+func Blank(img image.Image, clr color.Color, side imageutils.Side) image.Image {
+	return imageutils.Concat(img, blank{img, clr, side}, side)
+}