init

main.go

@@ -0,0 +1,138 @@
+package main
+
+import (
+	"bytes"
+	_ "embed"
+	"fmt"
+	"image"
+	"image/draw"
+	"image/jpeg"
+	"image/png"
+	"io"
+	"log"
+	"os"
+	"slices"
+	"strings"
+	"time"
+
+	tk "modernc.org/tk9.0"
+)
+
+//go:embed gopher.png
+var gopher []byte
+
+var validFileTypes = []tk.FileType{
+	{
+		TypeName:   "JPEG",
+		Extensions: []string{".jpg", ".jpeg"},
+	},
+	{
+		TypeName:   "GIF",
+		Extensions: []string{".gif"},
+	},
+	{
+		TypeName:   "PNG",
+		Extensions: []string{".png"},
+	},
+	{
+		TypeName:   "SVG",
+		Extensions: []string{".svg"},
+	},
+}
+
+var metaPressed bool
+
+func isType(filename string, desired string) bool {
+	splode := strings.Split(filename, ".")
+	if len(splode) < 2 {
+		return false
+	}
+	ext := fmt.Sprintf(".%s", splode[len(splode)-1])
+	for _, ft := range validFileTypes {
+		if slices.Contains(ft.Extensions, ext) && ft.TypeName == desired {
+			return true
+		}
+	}
+	return false
+}
+
+func jpegToPng(in io.Reader) (*bytes.Buffer, error) {
+	start := time.Now()
+	buf := new(bytes.Buffer)
+
+	img, err := jpeg.Decode(in)
+	if err != nil {
+		return nil, fmt.Errorf("unable to decode jpeg: %w", err)
+	}
+
+	b := img.Bounds()
+	dst := image.NewNRGBA(image.Rect(0, 0, b.Dx(), b.Dy()))
+	draw.Draw(dst, dst.Bounds(), img, b.Min, draw.Src)
+
+	if err := (&png.Encoder{
+		CompressionLevel: -2,
+	}).Encode(buf, dst); err != nil {
+		return nil, fmt.Errorf("unable to encode png: %w", err)
+	}
+	end := time.Now()
+	log.Printf("jpeg to png took %v", end.Sub(start))
+	return buf, nil
+}
+
+func loadImage(img *tk.LabelWidget) func() {
+	return func() {
+		files := tk.GetOpenFile(tk.Filetypes(validFileTypes))
+		if len(files) > 0 {
+			f, err := os.Open(files[0])
+			if err != nil {
+				log.Println(err.Error())
+				return
+			}
+			var r io.Reader
+			if isType(files[0], "JPEG") {
+				r, err = jpegToPng(f)
+				if err != nil {
+					log.Println(err.Error())
+					return
+				}
+			} else {
+				r = f
+			}
+			i, err := io.ReadAll(r)
+			if err != nil {
+				log.Println(err.Error())
+				return
+			}
+			img.Configure(tk.Image(tk.NewPhoto(tk.Data(i))))
+		}
+	}
+}
+
+func main() {
+	img := tk.Label(tk.Image(tk.NewPhoto(tk.Data(gopher))))
+
+	menubar := tk.Menu()
+	fileMenu := menubar.Menu()
+	fileMenu.AddCommand(tk.Lbl("Open"), tk.Underline(0), tk.Accelerator("Meta+O"), tk.Command(loadImage(img)))
+	menubar.AddCascade(tk.Lbl("File"), tk.Underline(0), tk.Mnu(fileMenu))
+
+	tk.Bind(tk.App, "<KeyPress>", tk.Command(func(e *tk.Event) {
+		if e.Keysym == "Meta_L" || e.Keysym == "Meta_R" {
+			metaPressed = true
+		}
+		if e.Keysym == "o" && metaPressed {
+			loadImage(img)()
+		}
+	}))
+	tk.Bind(tk.App, "<KeyRelease>", tk.Command(func(e *tk.Event) {
+		if e.Keysym == "Meta_L" || e.Keysym == "Meta_R" {
+			metaPressed = false
+		}
+	}))
+	tk.Bind(tk.App, "<MouseWheel>", tk.Command(func(e *tk.Event) {
+		log.Println(e)
+	}))
+
+	tk.Pack(img)
+	tk.App.Configure(tk.Mnu(menubar)).Center().Wait()
+}