move title generation into method

internal/epub/epub.go

@@ -99,6 +99,53 @@ func (e *ePub) writeBlank(wz *epubzip.EPUBZip, img *epubimage.Image) error {
 	)
 }
 
+// write title image
+func (e *ePub) writeTitleImage(wz *epubzip.EPUBZip, img *epubimage.Image, title string) error {
+	titleAlign := ""
+	if !e.Image.View.PortraitOnly {
+		if e.Image.Manga {
+			titleAlign = "right:0"
+		} else {
+			titleAlign = "left:0"
+		}
+	}
+
+	if !e.Image.View.PortraitOnly {
+		if err := wz.WriteContent(
+			"OEBPS/Text/space_title.xhtml",
+			[]byte(e.render(epubtemplates.Blank, map[string]any{
+				"Title":    "Blank Page Title",
+				"ViewPort": fmt.Sprintf("width=%d,height=%d", e.Image.View.Width, e.Image.View.Height),
+			})),
+		); err != nil {
+			return err
+		}
+	}
+
+	if err := wz.WriteContent(
+		"OEBPS/Text/title.xhtml",
+		[]byte(e.render(epubtemplates.Text, map[string]any{
+			"Title":      title,
+			"ViewPort":   fmt.Sprintf("width=%d,height=%d", e.Image.View.Width, e.Image.View.Height),
+			"ImagePath":  fmt.Sprintf("Images/title.%s", e.Image.Format),
+			"ImageStyle": img.ImgStyle(e.Image.View.Width, e.Image.View.Height, titleAlign),
+		})),
+	); err != nil {
+		return err
+	}
+
+	coverTitle, err := e.imageProcessor.CoverTitleData(img.Raw, title)
+	if err != nil {
+		return err
+	}
+
+	if err := wz.WriteRaw(coverTitle); err != nil {
+		return err
+	}
+
+	return nil
+}
+
 // extract image and split it into part
 func (e *ePub) getParts() (parts []*epubPart, imgStorage *epubzip.EPUBZipStorageImageReader, err error) {
 	images, err := e.imageProcessor.Load()
@@ -299,13 +346,6 @@ func (e *ePub) Write() error {
 		if totalParts > 1 {
 			title = fmt.Sprintf("%s [%d/%d]", title, i+1, totalParts)
 		}
-		titleAlign := ""
-		if !e.Image.View.PortraitOnly {
-			titleAlign = "left:0"
-			if e.Image.Manga {
-				titleAlign = "right:0"
-			}
-		}
 
 		content := []zipContent{
 			{"META-INF/container.xml", epubtemplates.Container},
@@ -326,21 +366,6 @@ func (e *ePub) Write() error {
 			{"OEBPS/Text/style.css", e.render(epubtemplates.Style, map[string]any{
 				"View": e.Image.View,
 			})},
-
-			{"OEBPS/Text/title.xhtml", e.render(epubtemplates.Text, map[string]any{
-				"Title":      title,
-				"ViewPort":   fmt.Sprintf("width=%d,height=%d", e.Image.View.Width, e.Image.View.Height),
-				"ImagePath":  fmt.Sprintf("Images/title.%s", e.Image.Format),
-				"ImageStyle": part.Cover.ImgStyle(e.Image.View.Width, e.Image.View.Height, titleAlign),
-			})},
-		}
-		if !e.Image.View.PortraitOnly {
-			content = append(content, zipContent{
-				"OEBPS/Text/space_title.xhtml", e.render(epubtemplates.Blank, map[string]any{
-					"Title":    "Blank Page Title",
-					"ViewPort": fmt.Sprintf("width=%d,height=%d", e.Image.View.Width, e.Image.View.Height),
-				}),
-			})
 		}
 
 		if err = wz.WriteMagic(); err != nil {
@@ -351,12 +376,8 @@ func (e *ePub) Write() error {
 				return err
 			}
 		}
-		coverTitle, err := e.imageProcessor.CoverTitleData(part.Cover.Raw, title)
-		if err != nil {
-			return err
-		}
 
-		if err := wz.WriteRaw(coverTitle); err != nil {
+		if err = e.writeTitleImage(wz, part.Cover, title); err != nil {
 			return err
 		}