add cbz support

main.go

@@ -1,9 +1,11 @@
 package main
 
 import (
+	"archive/zip"
 	_ "embed"
 	"fmt"
 	"image"
+	"io"
 	"log"
 	"os"
 	"path/filepath"
@@ -22,7 +24,12 @@ import (
 type state struct {
 	dir    string
 	i      int
-	images []string
+	images []imagefile
+}
+
+type imagefile struct {
+	contents *image.Image
+	filename string
 }
 
 //go:embed media/noise.png
@@ -41,7 +48,20 @@ var fileListBindVar = tk.Variable("FileList")
 var directoryState state
 
 func (d state) pathToImageAtIndex(i int) string {
-	return filepath.Join(directoryState.dir, directoryState.images[i])
+	return filepath.Join(directoryState.dir, directoryState.images[i].filename)
+}
+
+func (d state) imageWithFilename(s string) (imagefile, int, error) {
+	for i, f := range directoryState.images {
+		if f.filename == s {
+			return directoryState.images[i], i, nil
+		}
+	}
+	return imagefile{}, 0, fmt.Errorf("not found")
+}
+
+func (d state) setImage(i int, img *image.Image) {
+	d.images[i].contents = img
 }
 
 func must[T any](t T, err error) T {
@@ -62,7 +82,49 @@ func newFileInDirectory() {
 		return
 	}
 	// GetOpenFile returns an array split on spaces!
-	newBrowse(strings.Join(files, " "))
+	file := strings.Join(files, " ")
+	if filepath.Ext(file) == ".cbr" || filepath.Ext(file) == ".cbz" {
+		log.Println("Comic Book Archive!")
+		openArchive(file)
+		return
+	}
+	newBrowse(file)
+}
+
+func openArchive(path string) {
+	r, err := zip.OpenReader(path)
+	if err != nil {
+		log.Println(err)
+		return
+	}
+	clearFileList()
+	directoryState.images = []imagefile{}
+	for _, f := range r.File {
+		log.Println(f.FileInfo().Name())
+		if f.FileInfo().IsDir() {
+			continue
+		}
+		if f.FileInfo().Name()[0] == '.' {
+			continue
+		}
+		reader, err := f.Open()
+		if err != nil {
+			log.Println(err)
+			continue
+		}
+		i, err := decode(reader, f.FileInfo().Name())
+		if err != nil {
+			log.Println(err)
+			continue
+		}
+		directoryState.images = append(directoryState.images, imagefile{
+			contents: &i,
+			filename: f.FileInfo().Name(),
+		})
+		insertIntoFileList(f.FileInfo().Name())
+	}
+	moveSelectionInFileList(0)
+	updateImage(directoryState.images[0].filename)
 }
 
 func newDirectory() {
@@ -102,12 +164,12 @@ func newBrowse(file string) {
 	})
 	// ...that way we only have to do this loop once.
 	clearFileList()
-	directoryState.images = []string{}
+	directoryState.images = []imagefile{}
 	i := 0
 	for _, v := range dirfiles {
 		if filetypes.IsImage(v) {
-			directoryState.images = append(directoryState.images, v.Name())
-			insertIntoFileList(directoryState.images[i])
+			directoryState.images = append(directoryState.images, imagefile{filename: v.Name()})
+			insertIntoFileList(directoryState.images[i].filename)
 			if v.Name() == filepath.Base(file) {
 				directoryState.i = i
 				moveSelectionInFileList(i)
@@ -121,24 +183,28 @@ func newBrowse(file string) {
 func updateImage(file string) {
 	var i image.Image
 
-	f, err := os.Open(file)
+	entry, index, err := directoryState.imageWithFilename(filepath.Base(file))
 	if err != nil {
-		log.Printf("error opening image: %v", err)
+		log.Println(err.Error())
 		return
 	}
-	defer f.Close()
+	if entry.contents != nil {
+		fmt.Printf("loaded %s from cache\n", file)
+		i = *entry.contents
+	} else {
+		f, err := os.Open(file)
+		if err != nil {
+			log.Printf("error opening image: %v", err)
+			return
+		}
+		defer f.Close()
 
-	ext := strings.ToLower(strings.TrimPrefix(filepath.Ext(file), "."))
-	if checkErr(imaging.FormatFromExtension(ext)) {
-		i, err = imaging.Decode(f, imaging.AutoOrientation(true))
-	} else if ext == "webp" {
-		i, err = webp.Decode(f)
-	} else if ext == "tga" {
-		i, err = tga.Decode(f)
-	}
-	if err != nil {
-		log.Printf("error decoding image: %v", err)
-		return
+		i, err = decode(f, file)
+		if err != nil {
+			log.Printf("error decoding image: %v", err)
+			return
+		}
+		directoryState.setImage(index, &i)
 	}
 	i = imaging.Fit(i,
 		// -50 to give some space to breathe around the edges
@@ -149,6 +215,18 @@ func updateImage(file string) {
 	repaint(filepath.Base(file), tk.Data(i))
 }
 
+func decode(f io.Reader, name string) (image.Image, error) {
+	ext := strings.ToLower(strings.TrimPrefix(filepath.Ext(name), "."))
+	if checkErr(imaging.FormatFromExtension(ext)) {
+		return imaging.Decode(f, imaging.AutoOrientation(true))
+	} else if ext == "webp" {
+		return webp.Decode(f)
+	} else if ext == "tga" {
+		return tga.Decode(f)
+	}
+	return image.Black, fmt.Errorf("could not parse image")
+}
+
 func repaint(name string, data tk.Opt) {
 	// TODO: sometimes, when going from a big image to a smaller one,
 	// the window remains the same height as the big image,
@@ -229,7 +307,7 @@ func constructFileList() {
 	}))
 	clearFileList()
 	for i := range directoryState.images {
-		insertIntoFileList(directoryState.images[i])
+		insertIntoFileList(directoryState.images[i].filename)
 		if directoryState.i == i {
 			moveSelectionInFileList(i)
 		}