feat: use bookmark thumbnail as ebook cover (#943)

* use thumbnail as ebook cover

* add TODO for improve that later

Co-authored-by: Felipe Martin <812088+fmartingr@users.noreply.github.com>

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Co-authored-by: Felipe Martin <812088+fmartingr@users.noreply.github.com>

internal/core/ebook.go

@@ -62,6 +62,12 @@ func GenerateEbook(deps *dependencies.Dependencies, req ProcessRequest, dstPath
 
 	ebook.SetTitle(book.Title)
 	ebook.SetAuthor(book.Author)
+	if deps.Domains.Storage.FileExists(bookmarkThumbnailPath) {
+		// TODO: Use `deps.Domains.Storage` to retrieve the file.
+		absoluteCoverPath := fp.Join(deps.Config.Storage.DataDir, bookmarkThumbnailPath)
+		coverPath, _ := ebook.AddImage(absoluteCoverPath, "cover.jpg")
+		ebook.SetCover(coverPath, "")
+	}
 	ebook.SetDescription(book.Excerpt)
 	_, err = ebook.AddSection(`<h1 style="text-align:center"> `+book.Title+` </h1>`+book.HTML+lastline, book.Title, "", "")
 	if err != nil {