feat: Support for [gallery] shortcodes with no specific IDs

In WordPress, a gallery shortcode with no files will create a gallery of all attached media.
This commit mimics that behavior.

Ref: #68

src/wp2hugo/internal/hugogenerator/hugo_gen_setup.go

@@ -402,7 +402,8 @@ func (g Generator) newHugoPage(pageURL *url.URL, page wpparser.CommonFields) (*h
 		g.imageURLProvider,
 		*pageURL, page.Author, page.Title, page.PublishDate,
 		page.PublishStatus == wpparser.PublishStatusDraft || page.PublishStatus == wpparser.PublishStatusPending,
-		page.Categories, page.Tags, page.Footnotes, page.Content, page.GUID, page.FeaturedImageID, page.PostFormat)
+		page.Categories, page.Tags, g.wpInfo.GetAttachmentsForPost(page.PostID),
+		page.Footnotes, page.Content, page.GUID, page.FeaturedImageID, page.PostFormat)
 }
 
 func (g Generator) downloadPageMedia(outputMediaDirPath string, p *hugopage.Page, pageURL *url.URL) error {

src/wp2hugo/internal/hugogenerator/hugopage/hugo_page.go

@@ -31,8 +31,10 @@ const (
 type Page struct {
 	// This is the original URL of the page from the WordPress site
 	absoluteURL url.URL
-	metadata    map[string]any
-	markdown    string
+	attachments []wpparser.AttachmentInfo
+
+	metadata map[string]any
+	markdown string
 }
 
 const _WordPressMoreTag = "<!--more-->"
@@ -69,7 +71,8 @@ var _hugoAudioLinks = regexp.MustCompile(`{{< audio.*?src="([^\"]+?)".*? >}}`)
 var _hugoParallaxBlurLinks = regexp.MustCompile(`{{< parallaxblur.*?src="([^\"]+?)".*? >}}`)
 
 func NewPage(provider ImageURLProvider, pageURL url.URL, author string, title string, publishDate *time.Time,
-	isDraft bool, categories []string, tags []string, footnotes []wpparser.Footnote,
+	isDraft bool, categories []string, tags []string, attachments []wpparser.AttachmentInfo,
+	footnotes []wpparser.Footnote,
 	htmlContent string, guid *rss.GUID, featuredImageID *string, postFormat *string) (*Page, error) {
 	metadata, err := getMetadata(provider, pageURL, author, title, publishDate, isDraft, categories, tags, guid,
 		featuredImageID, postFormat)
@@ -79,6 +82,7 @@ func NewPage(provider ImageURLProvider, pageURL url.URL, author string, title st
 	page := Page{
 		absoluteURL: pageURL,
 		metadata:    metadata,
+		attachments: attachments,
 	}
 	// htmlContent is the HTML content of the page that will be
 	// transformed to Markdown
@@ -259,11 +263,16 @@ func (page *Page) getMarkdown(provider ImageURLProvider, htmlContent string, foo
 		msg := ""
 		return &msg, nil
 	}
+	attachmentIDs := make([]string, 0, len(page.attachments))
+	for _, attachment := range page.attachments {
+		attachmentIDs = append(attachmentIDs, attachment.PostID)
+	}
+
 	converter := getMarkdownConverter()
 	htmlContent = improvePreTagsWithCode(htmlContent)
 	htmlContent = replaceCaptionWithFigure(htmlContent)
 	htmlContent = replaceAudioShortCode(htmlContent)
-	htmlContent = replaceGalleryWithFigure(provider, htmlContent)
+	htmlContent = replaceGalleryWithFigure(provider, attachmentIDs, htmlContent)
 	htmlContent = replaceAWBWithParallaxBlur(provider, htmlContent)
 	htmlContent = strings.Replace(htmlContent, _WordPressMoreTag, _customMoreTag, 1)
 

src/wp2hugo/internal/hugogenerator/hugopage/hugo_page_test.go

@@ -62,7 +62,7 @@ func TestManualLineBreaks(t *testing.T) {
 func testMarkdownExtractor(t *testing.T, htmlInput string, markdownOutput string) {
 	url1, err := url.Parse("https://example.com")
 	assert.Nil(t, err)
-	page, err := NewPage(nil, *url1, "author", "Title", nil, false, nil, nil, nil, htmlInput, nil, nil, nil)
+	page, err := NewPage(nil, *url1, "author", "Title", nil, false, nil, nil, nil, nil, htmlInput, nil, nil, nil)
 	assert.Nil(t, err)
 	md, err := page.getMarkdown(nil, htmlInput, nil)
 	assert.Nil(t, err)

src/wp2hugo/internal/hugogenerator/hugopage/wordpress_gallery_converter.go

@@ -27,13 +27,13 @@ var galleryWithNoIDsErr = errors.New("no image IDs found in gallery shortcode")
 
 // Converts the WordPress's caption shortcode to Hugo shortcode "figure"
 // https://adityatelange.github.io/hugo-PaperMod/posts/papermod/papermod-faq/#centering-image-in-markdown
-func replaceGalleryWithFigure(provider ImageURLProvider, htmlData string) string {
+func replaceGalleryWithFigure(provider ImageURLProvider, attachmentIDs []string, htmlData string) string {
 	log.Debug().
 		Msg("Replacing gallery with figures")
 
 	htmlData = replaceAllStringSubmatchFunc(_GalleryRegEx, htmlData,
 		func(groups []string) string {
-			info, err := galleryReplacementFunction(provider, groups[1])
+			info, err := galleryReplacementFunction(provider, attachmentIDs, groups[1])
 			if err != nil {
 				return fmt.Sprintf("[gallery %s]", info) // Return the original shortcode
 			}
@@ -43,7 +43,7 @@ func replaceGalleryWithFigure(provider ImageURLProvider, htmlData string) string
 	return htmlData
 }
 
-func galleryReplacementFunction(provider ImageURLProvider, galleryInfo string) (string, error) {
+func galleryReplacementFunction(provider ImageURLProvider, attachmentIDs []string, galleryInfo string) (string, error) {
 	var output strings.Builder
 
 	// Find columns layout
@@ -56,10 +56,17 @@ func galleryReplacementFunction(provider ImageURLProvider, galleryInfo string) (
 	// Find image IDs
 	ids := _idRegEx.FindStringSubmatch(galleryInfo)
 	if len(ids) == 0 {
-		log.Warn().
-			Str("galleryInfo", galleryInfo).
-			Msg("No image IDs found in gallery shortcode")
-		return "", galleryWithNoIDsErr
+		if len(attachmentIDs) > 0 {
+			ids = []string{"", strings.Join(attachmentIDs, ",")}
+			log.Info().
+				Str("galleryInfo", galleryInfo).
+				Strs("attachmentIDs", attachmentIDs).
+				Msg("No image IDs found in gallery shortcode, fallback to page attachments")
+		} else {
+			log.Warn().
+				Msg("No image IDs found in gallery shortcode and no page attachments")
+			return "", galleryWithNoIDsErr
+		}
 	}
 
 	idsArray := strings.Split(ids[1], ",")