feat(gif): support gif file

See .gif file extension support and more exception handling
Fixes #105

pkg/converter/webp/webp_converter.go

@@ -6,6 +6,7 @@ import (
 	"errors"
 	"fmt"
 	"image"
+	_ "image/gif"
 	_ "image/jpeg"
 	"image/png"
 	"runtime"
@@ -167,10 +168,15 @@ func (converter *Converter) ConvertChapter(ctx context.Context, chapter *manga.C
 
 			splitNeeded, img, format, err := converter.checkPageNeedsSplit(page, split)
 			if err != nil {
-				select {
-				case errChan <- err:
-				case <-ctx.Done():
-					return
+				var pageIgnoredError *converterrors.PageIgnoredError
+				if errors.As(err, &pageIgnoredError) {
+					log.Info().Err(err).Msg("Page ignored due to image decode error")
+				} else {
+					select {
+					case errChan <- err:
+					case <-ctx.Done():
+						return
+					}
 				}
 				if img != nil {
 					wgConvertedPages.Add(1)
@@ -357,7 +363,7 @@ func (converter *Converter) checkPageNeedsSplit(page *manga.Page, splitRequested
 	img, format, err := image.Decode(reader)
 	if err != nil {
 		log.Debug().Uint16("page_index", page.Index).Err(err).Msg("Failed to decode page image")
-		return false, nil, format, err
+		return false, nil, format, converterrors.NewPageIgnored(fmt.Sprintf("page %d: failed to decode image (%s)", page.Index, err.Error()))
 	}
 
 	bounds := img.Bounds()

pkg/converter/webp/webp_converter_test.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"image"
 	"image/color"
+	"image/gif"
 	"image/jpeg"
 	"image/png"
 	"sync"
@@ -44,6 +45,11 @@ func encodeImage(img image.Image, format string) (*bytes.Buffer, string, error)
 			return nil, "", err
 		}
 		return buf, ".jpg", nil
+	case "gif":
+		if err := gif.Encode(buf, img, nil); err != nil {
+			return nil, "", err
+		}
+		return buf, ".gif", nil
 	case "webp":
 		PrepareEncoder()
 		if err := Encode(buf, img, 80); err != nil {
@@ -131,10 +137,11 @@ func TestConverter_ConvertChapter(t *testing.T) {
 			pages: []*manga.Page{
 				createTestPage(t, 1, 800, 1200, "png"),
 				createTestPage(t, 2, 800, 1200, "jpeg"),
+				createTestPage(t, 3, 800, 1200, "gif"),
 			},
 			split:       false,
 			expectSplit: false,
-			numExpected: 2,
+			numExpected: 3,
 		},
 		{
 			name:        "Tall image with split enabled",
@@ -147,7 +154,7 @@ func TestConverter_ConvertChapter(t *testing.T) {
 			name:        "Tall image without split",
 			pages:       []*manga.Page{createTestPage(t, 1, 800, webpMaxHeight+100, "png")},
 			split:       false,
-			expectError: true,
+			expectError: false,
 			numExpected: 1,
 		},
 	}
@@ -236,6 +243,12 @@ func TestConverter_convertPage(t *testing.T) {
 			isToBeConverted: true,
 			expectWebP:      true,
 		},
+		{
+			name:            "Convert GIF to WebP",
+			format:          "gif",
+			isToBeConverted: true,
+			expectWebP:      true,
+		},
 		{
 			name:            "Already WebP",
 			format:          "webp",
@@ -333,8 +346,8 @@ func TestConverter_ConvertChapter_Timeout(t *testing.T) {
 	// Create a test chapter with a few pages
 	pages := []*manga.Page{
 		createTestPage(t, 1, 800, 1200, "jpeg"),
-		createTestPage(t, 2, 800, 1200, "jpeg"),
-		createTestPage(t, 3, 800, 1200, "jpeg"),
+		createTestPage(t, 2, 800, 1200, "png"),
+		createTestPage(t, 3, 800, 1200, "gif"),
 	}
 
 	chapter := &manga.Chapter{