fix REUSE compliance

A complete rewrite of the gallery plugin:

* Using flexbox
* Using lightweight JS for lightbox to avoid anchor links, and allow full rotation
* Add slideshow as an additional field
* Make many more things configurable
* Better support for dirs, allow mixed paths
* Translatable captions for many files using metadata files
* SCSS instead of CSS

Reviewed-on: #1
Co-authored-by: Max Mehl <mail@mehl.mx>
Co-committed-by: Max Mehl <mail@mehl.mx>

README.md

@@ -1,108 +1,89 @@
 <!--
-  SPDX-FileCopyrightText: 2019 Li-Wen Yip <liwen.yip@gmail.com>
-  SPDX-FileCopyrightText: 2019 Max Mehl <mail@mehl.mx>
+  SPDX-FileCopyrightText: 2020 Max Mehl <mail@mehl.mx>
   SPDX-License-Identifier: MIT
 -->
 
 # hugo-snap-gallery
 
-Automagical css image gallery in [Hugo](https://gohugo.io/) using shortcodes.
+Automagical css image gallery in [Hugo](https://gohugo.io/) using shortcodes. Lightweight, slim and fully local JavaScript.
 
-This is a fork of [easy gallery](https://github.com/liwenyip/hugo-easy-gallery). It is supposed to come without any JavaScript and therefore has limited features, but new JS-less stuff is planned.
+## Features
 
-## Image Gallery Features
+- Custom `{{< snap-gallery >}}` shortcode that allows to display multiple images
+- Two modes:
+  - **slideshow** displaying only one image at a time with the ability to navigate
+  - **gallery** displaying all selected pictures next to each other
+- All pictures can be expanded on click in a lightbox
+- Manually select the images you want to display, or provide the path to a directory to use all images inside. This can be combined!
+- Next/prev buttons in slideshow and lightbox views
+- The gallery is responsive, images are scaled/cropped to fill 16:10 tiles
+- CSS and JS is automatically loaded the first time you use the `{{< snap-gallery >}}` shortcode on each page
+- Multiple galleries/slideshows per page supported, no interference
+- Automatic rotation of slideshow with a configurable interval. Can also be disabled.
+- Supports providing metadata such as `alt` and `title` attributes as well as captions
 
-- Custom `{{< figure >}}` shortcode that enables new features but is backwards-compatible with Hugo's built-in `{{< figure >}}`shortcode
-- Use the `{{< figure >}}` shortcode by itself to enable pretty captions
-- Put multiple `{{< figure >}}` shortcodes inside a `{{< gallery >}}` to create a pretty image gallery
-- **Point `{{< gallery >}}` at a directory to generate a gallery of all images in that directory**
-- Gallery is responsive, images are scaled/cropped to fill square (or other evenly-sized) tiles
-- Pretty captions appear/slide/fade upon hovering over the image 
-- Only requires 3.8kB of CSS (unminified; you can minify it if you want)
-- CSS is automatically loaded the first time you use the `{{< figure >}}` shortcode on each page
-
-## PhotoSwipe Features
-
-- Load PhotoSwipe by calling the `{{< load-photoswipe >}}` shortcode anywhere in your post
-- Loads all of the `<figure>` elements in your post, regardless of where in your post they appear, into a lightbox/carousel style image gallery
-- Works with any existing `<figure>` elements/shortcodes in your posts
-- Does not require you to [pre-define the image sizes](http://photoswipe.com/documentation/faq.html#image-size) (the initialisation script pre-loads the image to determine its size; you can optionally pre-define the image size if you want to avoid this pre-loading)
 
 ## Installation
 
-Use this like an additional Hugo theme.
-
-
-## `{{< figure >}}` shortcode usage
-
-Specifying your image files:
-
-- `{{< figure src="thumb.jpg" link="image.jpg" >}}` will use `thumb.jpg` for thumbnail and `image.jpg` for lightbox
-- `{{< figure src="image.jpg" >}}` or `{{< figure link="image.jpg" >}}` will use `image.jpg` for both thumbnail and lightbox
-- `{{< figure link="image.jpg" thumb="-small" >}}` will use `image-small.jpg` for thumbnail and `image.jpg` for lightbox
-
-Optional parameters:
-
-- All the [features/parameters](https://gohugo.io/extras/shortcodes) of Hugo's built-in `figure` shortcode work as normal, i.e. src, link, title, caption, class, attr (attribution), attrlink, alt
-- `size` (e.g. `size="1024x768"`) pre-defines the image size for PhotoSwipe. Use this option if you don't want to pre-load the linked image to determine its size.
-- `class` allows you to set any custom classes you want on the `<figure>` tag.
-
-Optional parameters for standalone `{{< figure >}}` shortcodes only (i.e. don't use on `{{< figure >}}` inside `{{< gallery >}}` - strange things may happen if you do): 
-
-- `caption-position` and `caption-effect` work the same as for the `{{< gallery >}}` shortcode (see below). 
-- `width` defines the [`max-width`](https://www.w3schools.com/cssref/pr_dim_max-width.asp) of the image displayed on the page. If using a thumbnail for a standalone figure, set this equal to your thumbnail's native width to make the captions behave properly (or feel free to come up with a better solution and submit a pull request :-)). Also use this option if you don't have a thumbnail and you don't want the hi-res image to take up the entire width of the screen/container. 
-
-
-## `{{< gallery >}}` shortcode usage
-
-To specify a directory of image files:
+Use this like an additional Hugo theme, so add it to the `theme` config. Example:
 
 ```
-{{< gallery dir="/img/your-directory-of-images/" />}}`
+theme = [ "hugo-sustain", "hugo-snap-gallery" ]
 ```
 
-- The images are automatically captioned with the file name.
-- `[image].jpg` is used for the hi-res image, and `[image]-thumb.jpg` is used for the thumbnails.
-- If `[image]-thumb.jpg` doesn't exist, then `[image].jpg` will be used for both hi-res and thumbnail images.
-- The default thumbnail suffix is `-thumb`, but you can specify a different one e.g. `thumb="-small"` or `thumb="_150x150"`.
+## `{{< snap-gallery >}}` shortcode usage
 
-To specify individual image files:
+Quickstart:
 
-```
-{{< gallery >}}
-  {{< figure src="image1.jpg" >}}
-  {{< figure src="image2.jpg" >}}
-  {{< figure src="image3.jpg" >}}
-{{< /gallery >}}
+- `{{< snap-gallery src="image1.jpg, image2.png" >}}`: Display these two images in **gallery** mode
+- `{{< snap-gallery src="image1.jpg, image2.png" mode="slideshow" >}}`: Display these two images in **slideshow** mode
+- `{{< snap-gallery src="img/folder1/, image2.png" >}}`: Display all images in the directory `img/folder1` and the single image `image2.png` in **gallery** mode
+
+All parameters:
+
+- `src`: Must contain either a comma-separated list of paths to images, or a directory path containing images. Note that the paths are absolute, so imagine a `/` in front of them. Also note that the shortcode assumes that they are all stored in `/static/`.
+- `lightbox`: Whether a click on an image shall open a lightbox modal. Default: `true`.
+- `aspectratio`: Define the aspect ratio of the images in the slideshow/gallery. Default: `16/10`.
+- `metadata`: See below for how to add metadata to your files. Default: `map[]`.
+- `mode`: Can be either `gallery` or `slideshow`. Default: `gallery`.
+- For gallery mode:
+  - `columns`: Amount of columns the images are displayed in. Default: `4`.
+  - `minwidth`: Minimum width that each image shall have, e.g. `150px` or `30%`. May conflict with the desired amount of columns. Default: `200px`.
+- For slideshow mode:
+  - `slideshowwidth`: Width of slideshow, e.g. `300px` or `80%`. Default: `100%`.
+  - `slideshowrotate`: Whether the slideshow shall automatically rotate through the images. Default: `true`.
+  - `slideshowrotate_timer`: Interval of automatic slideshow rotation (if enabled), in milliseconds. Default: `5000` (5 seconds).
+
+**Note: Boolean values (`true`/`false`) must be provided without surrounding `"` characters!** `lightbox=false` disables the lightbox, while `lightbox="false"` does not.
+
+### Metadata
+
+Using separate data files, you can provide metadata to the image files. Imagine using the following shortcode: `{{< snap-gallery src="image1.jpg, img/folder1/" metadata="images.en" >}}`.
+
+This would assume you have a file named `/data/images.en.yaml`. It may contain the following data:
+
+```yaml
+- src: image1.jpg
+  html:
+    alt: Alternative text
+    title: Title, text displayed when hovering
+- src: img/folder1/foo.png
+  html:
+    alt: Alternative text for the first picture in the image folder
 ```
 
-Optional parameters:
+This way, you can add any HTML attributes to the `<img>` element for the images you describe in the metadata file. In this example, you add this for two images, one of them is in a folder whose path you provided. You don't have to add information for all files.
 
-- `caption-position` - determines the captions' position over the image. Options:
-  - `bottom` (default)
-  - `center`
-  - `none` hides captions on the page (they will only show in PhotoSwipe)
-- `caption-effect` - determines if/how captions appear upon hover. Options:
-  - `slide` (default)
-  - `fade`
-  - `none` (captions always visible)
-- `hover-transition` - determines if/how images change upon hover. Options:
-  - not set - smooth transition (default)
-  - `none` - hard transition
+This flexible way allows you to also translate metadata. Just use different `metadata` values to the shortcodes depending on the language.
 
+Note that a `title` is also taken as a caption to the picture in order to reduce duplicated work.
 
-## CSS Hackers
+## Credits
 
-`snap-gallery.css` is designed to provide square tiles in a container with `max-width: 768px`.
-
-Here are some pointers if you want to adapt the CSS:
-
- - Change `.gallery {max-width: 768px;}` if you want a gallery wider than 768px.
- - Change `min-width` in the `@media` styles to change the screen widths at which the layout changes
- - Change `min-width: 9999px` in the last `@media` style to something sensible if you want to use a 4-tile layout
- - If you want more than 4 tiles per row, set `width` = 100% / number of tiles per row
- - `padding-bottom` = `width` gives square tiles. Change padding-bottom if you want some other aspect ratio, e.g. `width: 33.3%; padding-bottom: 25%` gives a 4:3 aspect ratio.
+The original inspiration for this shortcode came from [Li-Wen Yip's easy-gallery](https://github.com/liwenyip/hugo-easy-gallery). The first major version of this was already a 90% rewrite, and the current one has even less to do with it. However, the rewrite took some inspirations from [W3Schools](https://www.w3schools.com/howto/howto_js_lightbox.asp), thanks!
 
 ## License
 
-MIT
+This repository follows the REUSE best practices for clear copyright and licensing information. The license texts for all used licenses can be found in the LICENSES/ directory under the root of this repository. Visit [reuse.software](https://reuse.software) for more information.
+
+The main license of this repo is MIT.

assets/scss/snap-gallery.scss

@@ -0,0 +1,260 @@
+/*
+  SPDX-FileCopyrightText: 2024 Max Mehl <https://mehl.mx>
+  SPDX-License-Identifier: MIT
+*/
+
+$gap: var(--gap);
+
+.snap-gallery,
+.snap-slideshow {
+  display: flex;
+  justify-content: center;
+  align-items: center;
+  position: relative;
+  margin-bottom: 15px;
+
+  /* Create equal columns in flexbox */
+  .snap-image {
+    cursor: var(--cursor);
+
+    /* Column amount and width are configurable by style variables */
+    width: calc(100% / var(--columns) - #{$gap});
+    min-width: var(--min-width);
+
+    img {
+      aspect-ratio: var(--aspectratio);
+      width: 100%;
+      object-fit: cover;
+    }
+  }
+}
+
+.snap-gallery {
+  flex-wrap: wrap;
+  gap: $gap;
+}
+
+.snap-slideshow {
+  width: var(--slideshow-width);
+  margin-left: auto;
+  margin-right: auto;
+
+  // Hide all contained images except the first
+  .snap-image:not(:first-child) {
+    display: none;
+  }
+}
+
+// Animation
+.snap-slideshow .snap-image,
+.snap-lightbox .snap-lightbox-inner {
+  animation: 1s fade;
+
+  @keyframes fade {
+    from {
+      opacity: .4
+    }
+
+    to {
+      opacity: 1
+    }
+  }
+}
+
+.snap-lightbox {
+  /** Default lightbox to hidden */
+  display: none;
+
+  /** Position and style */
+  position: fixed;
+  z-index: 999;
+  width: 100%;
+  height: 100%;
+  text-align: center;
+  white-space: nowrap;
+  top: 0;
+  left: 0;
+  background: rgba(0, 0, 0, 0.8);
+
+  /* keep lightbox in middle. TODO: hacky, and not realibly in middle */
+  &:before {
+    content: "";
+    display: inline-block;
+    vertical-align: middle;
+    width: 0;
+    /* adjust for white space between pseudo element and next sibling */
+    margin-right: -.25em;
+    /* stretch line height */
+    height: 100%;
+  }
+}
+
+// Disable cursor selection in lightbox and on slideshow, especially controls
+.snap-lightbox,
+.snap-slideshow {
+  user-select: none;
+}
+
+// /* Click on the complete background closes the lightbox */
+// /* Exception: arrow in gallery, they have higher z-index */
+// a.snap-lightbox-close {
+//   position: fixed;
+//   z-index: 800;
+//   width: 100%;
+//   height: 100%;
+//   text-align: center;
+//   white-space: nowrap;
+//   top: 0;
+//   left: 0;
+// }
+
+/* Container for image */
+.snap-lightbox-inner {
+  display: inline-block;
+  vertical-align: middle;
+  white-space: normal;
+  max-width: 90%;
+  max-height: 80%;
+  height: 100%;
+
+  img {
+    max-height: 100%;
+  }
+
+  @media screen and (max-width: 767px) {
+    max-width: 80%;
+  }
+}
+
+/* Number text (1/3 etc) and captions*/
+.snap-numbertext {
+  position: absolute;
+  color: #f2f2f2;
+  background-color: #000;
+  font-size: 12px;
+  padding: 8px 12px;
+}
+
+.snap-caption {
+  bottom: 0;
+  color: #f2f2f2;
+  padding: 8px 0;
+  left: 10%;
+  width: 80%;
+  text-shadow: 1px 1px 10px #000;
+  font-weight: 700;
+  font-size: 1.1em;
+  text-align: center;
+
+  // As slideshow, position on picture on mid-screens and wider
+  .snap-slideshow & {
+    position: absolute;
+
+    @media screen and (max-width: 767px) {
+      display: none;
+    }
+  }
+  // In lightbox, always show below picture
+  .snap-lightbox & {
+    position: relative;
+  }
+}
+
+// /* Caption text */
+// .caption-container {
+//   text-align: center;
+//   background-color: black;
+//   padding: 2px 16px;
+//   color: white;
+// }
+
+/* prev/next arrows & close button */
+.snap-prev,
+.snap-next {
+  color: #fff;
+  text-decoration: none !important;
+  font-size: 30px;
+
+  position: absolute;
+  height: 100%;
+  z-index: 800;
+  width: 5%;
+  cursor: pointer;
+
+  // Slideshow specifics
+  .snap-slideshow & {
+    display: flex;
+    justify-content: center;
+    align-items: center;
+
+    background-color: rgba(0, 0, 0, 0.7);
+
+    height: 15%;
+    width: 10%;
+    min-height: 50px;
+    min-width: 50px;
+
+    &:hover {
+      background-color: rgba(0, 0, 0, 0.8);
+      transition: all 0.25s ease;
+    }
+  }
+
+  // Lightbox-specifics
+  .snap-lightbox & {
+    @media screen and (max-width: 767px) {
+      width: 10%;
+    }
+  }
+
+  // Item containing arrow
+  span {
+    padding: 1%;
+
+    // Lightbox specifics
+    .snap-lightbox & {
+      position: fixed;
+      top: 50%;
+    }
+  }
+}
+
+// Position arrows for left/right
+.snap-prev {
+  left: 0;
+
+  .snap-lightbox & span {
+    left: 0.5%;
+  }
+}
+
+.snap-next {
+  right: 0;
+
+  .snap-lightbox & span {
+    right: 0.5%;
+  }
+}
+
+/* The Close Button */
+.snap-close {
+  display: flex;
+  justify-content: center;
+  align-items: center;
+  position: absolute;
+  top: 15px;
+  right: 15px;
+  height: 50px;
+  width: 50px;
+  color: white;
+  font-size: 50px;
+  font-weight: bold;
+  z-index: 900;
+
+  &:hover,
+  &:focus {
+    color: #999;
+    text-decoration: none;
+    cursor: pointer;
+  }
+}

layouts/partials/gallery.html

@@ -0,0 +1,18 @@
+<!--
+  SPDX-FileCopyrightText: 2024 Max Mehl <https://mehl.mx>
+  SPDX-License-Identifier: MIT
+-->
+{{- $imgs := .imgs -}}
+{{- $galno := .galno -}}
+<div class="snap-gallery" style="--columns:{{ default 4 .columns }};--min-width:{{ default "200px" .minwidth }};--gap:10px;--cursor:{{ .cursor }};--aspectratio:{{ safeCSS (default "16/10" .aspectratio) }};">
+  {{- range $i, $img := $imgs }}
+  <div class="snap-image">
+    <img
+      src="{{ relURL $img.src }}"
+      {{ range $attr, $value := $img.html -}}
+        {{ safeHTMLAttr $attr }}={{ $value }}
+      {{ end -}}
+      onclick="openLightbox({{ $galno }});openLightboxItem({{ $galno }}, {{ add $i 1 }});" />
+  </div>
+  {{- end }}
+</div>

layouts/partials/lightbox.html

@@ -0,0 +1,28 @@
+<!--
+  SPDX-FileCopyrightText: 2024 Max Mehl <https://mehl.mx>
+  SPDX-License-Identifier: MIT
+-->
+{{- $imgs := .imgs -}}
+{{- $galno := .galno -}}
+<div class="snap-lightbox" id="snap-lightbox-{{ $galno }}">
+  {{- range $i, $img := $imgs }}
+  <div class="snap-lightbox-inner">
+    <div class="snap-numbertext">{{ add $i 1 }} / {{ len $imgs }}</div>
+    <img
+      src="{{ relURL $img.src }}"
+      {{ range $attr, $value := $img.html -}}
+        {{ safeHTMLAttr $attr }}={{ $value }}
+      {{ end -}}
+    />
+    {{- with $img.html.title }}
+      <div class="snap-caption">{{ . }}</div>
+    {{- end }}
+  </div>
+  {{- end -}}
+
+  <!-- Close and Next/previous controls -->
+  <span class="snap-close" onclick="closeLightbox({{ $galno }})">&times;</span>
+
+  <a class="snap-prev" onclick="moveLightboxItem({{ $galno }}, -1)"><span>&#10094;</span></a>
+  <a class="snap-next" onclick="moveLightboxItem({{ $galno }}, 1)"><span>&#10095;</span></a>
+</div>

layouts/partials/slideshow.html

@@ -0,0 +1,25 @@
+<!--
+  SPDX-FileCopyrightText: 2024 Max Mehl <https://mehl.mx>
+  SPDX-License-Identifier: MIT
+-->
+{{- $imgs := .imgs -}}
+{{- $galno := .galno -}}
+<div class="snap-slideshow" id="snap-slideshow-{{ $galno }}" style="--columns:1;--min-width:0px;--gap:0px;--slideshow-width:{{ default "100%" .width }};--cursor:{{ .cursor }};--aspectratio:{{ safeCSS (default "16/10" .aspectratio) }};">
+  {{- range $i, $img := $imgs }}
+  <div class="snap-image">
+    <div class="snap-numbertext">{{ add $i 1 }} / {{ len $imgs }}</div>
+    {{- with $img.html.title }}
+      <div class="snap-caption">{{ . }}</div>
+    {{- end }}
+    <img
+      src="{{ relURL $img.src }}"
+      {{ range $attr, $value := $img.html -}}
+        {{ safeHTMLAttr $attr }}={{ $value }}
+      {{ end -}}
+      onclick="openLightbox({{ $galno }});openLightboxItem({{ $galno }}, {{ add $i 1 }});" />
+  </div>
+  {{- end }}
+
+  <a class="snap-prev" onclick="moveSlideshowItem({{ $galno }}, -1)"><span>&#10094;</span></a>
+  <a class="snap-next" onclick="moveSlideshowItem({{ $galno }}, 1)"><span>&#10095;</span></a>
+</div>

layouts/shortcodes/figure.html

@@ -1,33 +0,0 @@
-<!--
-  SPDX-FileCopyrightText: 2019 Li-Wen Yip <liwen.yip@gmail.com>
-  SPDX-FileCopyrightText: 2019 Max Mehl <mail@mehl.mx>
-  SPDX-License-Identifier: MIT
-
-  Put this file in /layouts/shortcodes/figure.html
-  NB this overrides Hugo's built-in "figure" shortcode but is backwards compatible
-  Documentation and licence at https://github.com/liwenyip/hugo-easy-gallery/
--->
-<!-- count how many times we've called this shortcode; load the css if it's the first time -->
-{{- if not ($.Page.Scratch.Get "figurecount") }}<link rel="stylesheet" href="/css/snap-gallery.css" />{{ end }}
-{{- $.Page.Scratch.Add "figurecount" 1 -}}
-<!-- use either src or link-thumb for thumbnail image -->
-{{- $thumb := .Get "src" | default (printf "%s." (.Get "thumb") | replace (.Get "link") ".") }}
-<div class="box{{ with .Get "caption-position" }} fancy-figure caption-position-{{.}}{{end}}{{ with .Get "caption-effect" }} caption-effect-{{.}}{{end}}" {{ with .Get "width" }}style="max-width:{{.}}"{{end}}>
-  <figure {{ with .Get "class" }}class="{{.}}"{{ end }} itemprop="associatedMedia" itemscope itemtype="http://schema.org/ImageObject">
-    <div class="img"{{ if .Parent }} style="background-image: url('{{ $thumb | relURL }}');"{{ end }}{{ with .Get "size" }} data-size="{{.}}"{{ end }}>
-      <img itemprop="thumbnail" src="{{ $thumb | relURL }}" {{ with .Get "alt" | default (.Get "caption") }}alt="{{.}}"{{ end }}/><!-- <img> hidden if in .gallery -->
-    </div>
-    {{ with .Get "link" | default (.Get "src") }}<a href="{{.}}" itemprop="contentUrl"></a>{{ end }}
-    {{- if or (or (.Get "title") (.Get "caption")) (.Get "attr")}}
-      <figcaption>
-        {{- with .Get "title" }}<h4>{{.}}</h4>{{ end }}
-        {{- if or (.Get "caption") (.Get "attr")}}
-          <p>
-            {{- .Get "caption" -}}
-            {{- with .Get "attrlink"}}<a href="{{.}}">{{ .Get "attr" }}</a>{{ else }}{{ .Get "attr"}}{{ end -}}
-          </p>
-        {{- end }}
-      </figcaption>
-    {{- end }}
-  </figure>
-</div>

layouts/shortcodes/gallery.html

@@ -1,45 +0,0 @@
-<!--
-  SPDX-FileCopyrightText: 2019 Li-Wen Yip <liwen.yip@gmail.com>
-  SPDX-FileCopyrightText: 2019 Max Mehl <mail@mehl.mx>
-  SPDX-License-Identifier: MIT
-
-  Put this file in /layouts/shortcodes/gallery.html
-  Documentation and licence at https://github.com/liwenyip/hugo-easy-gallery/
--->
-<!-- count how many times we've called this shortcode; load the css if it's the first time -->
-<link rel="stylesheet" href="/css/snap-gallery.css" />
-{{- $.Page.Scratch.Add "figurecount" 1 }}
-{{ $baseURL := .Site.BaseURL }}
-<div class="gallery caption-position-{{ with .Get "caption-position" | default "bottom" }}{{.}}{{end}} caption-effect-{{ with .Get "caption-effect" | default "slide" }}{{.}}{{end}} hover-effect-{{ with .Get "hover-effect" | default "zoom" }}{{.}}{{end}} {{ if ne (.Get "hover-transition") "none" }}hover-transition{{end}}" itemscope itemtype="http://schema.org/ImageGallery">
-	{{- with (.Get "dir") -}}
-		<!-- If a directory was specified, generate figures for all of the images in the directory -->
-		{{- $files := readDir (print "/static/" .) }}
-		{{- range $files -}}
-			<!-- skip files that aren't images, or that inlcude the thumb suffix in their name -->
-			{{- $thumbext := $.Get "thumb" | default "-thumb" }}
-			{{- $isthumb := .Name | findRE ($thumbext | printf "%s\\.") }}<!-- is the current file a thumbnail image? -->
-			{{- $isimg := lower .Name | findRE "\\.(gif|jpg|jpeg|tiff|png|bmp)" }}<!-- is the current file an image? -->
-			{{- if and $isimg (not $isthumb) }}
-				{{- $caption :=  .Name | replaceRE "\\..*" "" | humanize }}<!-- humanized filename without extension -->
-				{{- $linkURL := print $baseURL ($.Get "dir") "" .Name | absURL }}<!-- absolute URL to hi-res image -->
-				{{- $thumb := .Name | replaceRE "(\\.)" ($thumbext | printf "%s.") }}<!-- filename of thumbnail image -->
-				{{- $thumbexists := where $files "Name" $thumb }}<!-- does a thumbnail image exist? --> 
-				{{- $thumbURL := print $baseURL ($.Get "dir") "/" $thumb | absURL }}<!-- absolute URL to thumbnail image -->
-				<div class="box">
-				  <figure itemprop="associatedMedia" itemscope itemtype="http://schema.org/ImageObject">
-				    <div class="img" style="background-image: url('{{ if $thumbexists }}{{ $thumbURL }}{{ else }}{{ $linkURL }}{{ end }}');" >
-				      <img itemprop="thumbnail" src="{{ if $thumbexists }}{{ $thumbURL }}{{ else }}{{ $linkURL }}{{ end }}" alt="{{ $caption }}" /><!-- <img> hidden if in .gallery -->
-				    </div>
-			      <figcaption>
-		          <p>{{ $caption }}</p>
-			      </figcaption>
-				    <a href="{{ $linkURL }}" itemprop="contentUrl" class="hiddenlink" target="_blank"></a><!-- put <a> last so it is stacked on top -->
-				  </figure>
-				</div>
-			{{- end }}
-		{{- end }}
-	{{- else -}}
-		<!-- If no directory was specified, include any figure shortcodes called within the gallery -->
-	  {{ .Inner }}
-	{{- end }}
-</div>

layouts/shortcodes/snap-gallery.html

@@ -0,0 +1,87 @@
+<!--
+  SPDX-FileCopyrightText: 2024 Max Mehl <https://mehl.mx>
+  SPDX-License-Identifier: MIT
+-->
+{{/*  Count number of gallery on page  */}}
+{{- $.Page.Scratch.Add "gallerycount" 1 -}}
+{{- $galno := $.Page.Scratch.Get "gallerycount" -}}
+
+{{/*  Load CSS/JS and make sure it is only loaded once  */}}
+{{- if eq ($.Page.Scratch.Get "gallerycount") 1 -}}
+{{- with resources.Get "scss/snap-gallery.scss" | toCSS -}}
+<link rel="stylesheet" href="{{ .RelPermalink }}" crossorigin="anonymous">
+{{- end -}}
+<script src="/js/snap-gallery.js"></script>
+{{- end -}}
+
+{{/*  Initialise index of this gallery  */}}
+<script>imageIndex[{{ $galno }}] = 1;</script>
+
+{{/*  Initialise variables holding image paths and extension  */}}
+{{- $imgs_collect := slice -}}
+{{- $imgs := slice -}}
+{{- $img_exts := slice ".jpg" ".jpeg" ".png" ".gif" ".webp" ".tiff" -}}
+
+{{/*  Get information from optional metadata file  */}}
+{{- $metadata := dict -}}
+{{- with .Params.metadata -}}
+  {{- $metadata = index $.Site.Data . -}}
+{{- end -}}
+
+{{/*  Get images from src Param, separated by comma  */}}
+{{- range (split .Params.src ",") -}}
+  {{- $img := (trim . " ") -}}
+  {{- $img_static := print "/static/" $img -}}
+  {{/*  Only proceed when path exists  */}}
+  {{- if os.FileExists $img_static -}}
+    {{/*  If current item is a directory, range each of them, and add with full path to the slice  */}}
+    {{- if (os.Stat $img_static).IsDir -}}
+      {{- range readDir $img_static -}}
+        {{- $imgs_collect = $imgs_collect | append (path.Join $img .Name ) -}}
+      {{- end -}}
+    {{/*  If a single file, just add it to the slice  */}}
+    {{- else -}}
+      {{- $imgs_collect = $imgs_collect | append $img -}}
+    {{- end -}}
+  {{- end -}}
+{{- end -}}
+
+{{/*  Filter collected files, store them as slice of dicts/maps  */}}
+{{- range $imgs_collect -}}
+  {{/*  Only process files if they are recognised as an image  */}}
+  {{- if in $img_exts (lower (path.Ext .)) -}}
+    {{/*  Create a dict holding path and optional metadata  */}}
+    {{- $imgdict := dict "src" . -}}
+    {{/*  If metadata for this image path found, add all of it to dict  */}}
+    {{- $img_metadata := where $metadata "src" . -}}
+    {{- with $img_metadata -}}
+      {{- $imgdict = merge $imgdict (index . 0) -}}
+    {{- end -}}
+    {{/*  Add final dict to slice  */}}
+    {{- $imgs = $imgs | append $imgdict -}}
+  {{- end -}}
+{{- end -}}
+
+{{/*  Define cursor when hovering over images, depending on lightbox status  */}}
+{{- $lightbox := (default true .Params.lightbox) -}}
+{{- $cursor := "auto" -}}
+{{- if $lightbox }}{{ $cursor = "zoom-in" }}{{ end -}}
+
+{{/*  Visible images in separate modes  */}}
+{{- $mode := default "gallery" .Params.mode -}}
+{{/*  Gallery mode  */}}
+{{- if eq $mode "gallery" -}}
+{{- partial "gallery" (dict "columns" .Params.columns "minwidth" .Params.minwidth "imgs" $imgs "galno" $galno "cursor" $cursor "aspectratio" .Params.aspectratio) -}}
+{{/*  Slideshow mode  */}}
+{{- else if eq $mode "slideshow" -}}
+{{- partial "slideshow" (dict "imgs" $imgs "galno" $galno "width" .Params.slideshowwidth "cursor" $cursor "aspectratio" .Params.aspectratio) -}}
+{{/*  Set autorotate timer for slideshow, if configured (default: yes)  */}}
+{{- if (default true .Params.slideshowrotate) -}}
+<script>const autoSlideshow = setInterval(moveSlideshowItem, {{ default 5000 .Params.slideshowrotate_timer }}, {{ $galno }}, 1, "auto");</script>
+{{- end -}}
+{{- end -}}
+
+{{/*  The Modal/Lightbox  */}}
+{{ if $lightbox -}}
+{{- partial "lightbox" (dict "galno" $galno "imgs" $imgs) -}}
+{{- end -}}

static/css/snap-gallery.css

@@ -1,165 +0,0 @@
-/*
-  SPDX-FileCopyrightText: 2019 Li-Wen Yip <liwen.yip@gmail.com>
-  SPDX-FileCopyrightText: 2019 Max Mehl <mail@mehl.mx>
-  SPDX-License-Identifier: MIT
-
-  Put this file in /static/css/hugo-easy-gallery.css
-  Documentation and licence at https://github.com/liwenyip/hugo-easy-gallery/
-*/
-
-
-/*
-Grid Layout Styles
-*/
-.gallery {
-    overflow: hidden;
-    margin: 10px;
-    max-width: 768px;
-    display: flex;
-    flex-wrap: wrap;
-}
-.gallery .box {
-    float: left;
-    position: relative;
-    /* Default: 1 tile wide */
-    width: 100%;
-    padding-bottom: 100%;
-    margin: 0 auto;
-}
-@media only screen and (min-width : 365px) {
-    /* Tablet view: 2 tiles */
-    .gallery .box {
-        width: 50%;
-        padding-bottom: 50%;
-    }
-}
-@media only screen and (min-width : 480px) {
-    /* Small desktop / ipad view: 3 tiles */
-    .gallery .box {
-        width: 33.3%;
-        padding-bottom: 33.3%; /*  */
-    }
-}
-@media only screen and (min-width : 9999px) {
-   /* Medium desktop: 4 tiles */
-   .box {
-      width: 25%;
-      padding-bottom: 25%;
-   }
-}
-
-/*
-Transition styles
-*/
-.gallery.hover-transition figure,
-.gallery.hover-effect-zoom .img, 
-.gallery:not(.caption-effect-appear) figcaption,
-.fancy-figure:not(.caption-effect-appear) figcaption {
-    -webkit-transition: all 0.3s ease-in-out;
-    -moz-transition: all 0.3s ease-in-out;
-    -o-transition: all 0.3s ease-in-out;
-    transition: all 0.3s ease-in-out;
-}
-/*
-figure styles
-*/
-figure {
-    position:relative; /* purely to allow absolution positioning of figcaption */
-    overflow: hidden;
-}
-.gallery figure {
-    position: absolute;
-    left: 5px;
-    right: 5px;
-    top: 5px;
-    bottom: 5px;
-}
-.gallery.hover-effect-grow figure:hover {
-    transform: scale(1.05);
-}
-.gallery.hover-effect-shrink figure:hover {
-    transform: scale(0.95);
-}
-.gallery.hover-effect-slidedown figure:hover {
-    transform: translateY(5px);
-}
-.gallery.hover-effect-slideup figure:hover {
-    transform: translateY(-5px);
-}
-
-/*
-img / a styles
-*/
-
-.gallery .img {
-    position: absolute;
-    left: 0;
-    right: 0;
-    top: 0;
-    bottom: 0;
-    background-size: cover;
-    background-position: 50% 50%;
-    background-repeat: no-repeat;
-}
-.gallery.hover-effect-zoom figure:hover .img {
-    transform: scale(1.05);
-}
-.gallery img {
-    display: none; /* only show the img if not inside a gallery */
-}
-figure a {
-    position: absolute;
-    left: 0;
-    right: 0;
-    top: 0;
-    bottom: 0;
-}
-
-/*
-figcaption styles
-*/
-.gallery figcaption,
-.fancy-figure figcaption {
-    position: absolute;
-    bottom: 0;
-    left: 0;
-    right: 0;
-    background: #000;
-    color: #FFF;
-    text-align: center;
-    font-size: 75%; /* change this if you want bigger text */
-    background: rgba(0, 0, 0, 0.5);
-    opacity: 1;
-    cursor: pointer;
-}
-.gallery.caption-position-none figcaption,
-.fancy-figure.caption-position-none figcaption  {
-    display: none;
-}
-.gallery.caption-position-center figcaption,
-.fancy-figure.caption-position-center figcaption {
-    top: 0;
-    padding: 40% 5px;
-}
-.gallery.caption-position-bottom figcaption,
-.fancy-figure.caption-position-bottom figcaption {
-    padding: 5px;
-}
-.gallery.caption-effect-fade figure:not(:hover) figcaption,
-.gallery.caption-effect-appear figure:not(:hover) figcaption,
-.fancy-figure.caption-effect-fade figure:not(:hover) figcaption,
-.fancy-figure.caption-effect-appear figure:not(:hover) figcaption {
-    background: rgba(0, 0, 0, 0);
-    opacity: 0;
-}
-.gallery.caption-effect-slide.caption-position-bottom figure:not(:hover) figcaption,
-.fancy-figure.caption-effect-slide.caption-position-bottom figure:not(:hover) figcaption {
-    margin-bottom: -100%;
-}
-.gallery.caption-effect-slide.caption-position-center figure:not(:hover) figcaption,
-.fancy-figure.caption-effect-slide.caption-position-center figure:not(:hover) figcaption  {
-    top: 100%;
-}
-figcaption p {
-    margin: auto; /* override style in theme */
-}

static/js/snap-gallery.js

@@ -0,0 +1,80 @@
+/*
+  SPDX-FileCopyrightText: 2023 Max Mehl <https://mehl.mx>
+  SPDX-License-Identifier: MIT
+*/
+
+// Variables
+var lightbox_baseid = "snap-lightbox-";
+var slideshow_baseid = "snap-slideshow-";
+//var imageIndex = {1: 1, 2: 1, 3: 1};
+var imageIndex  = {}
+
+// Open the Lightbox
+function openLightbox(id) {
+  document.getElementById(lightbox_baseid + id).style.display = "block";
+
+  // Kill automatic slideshow when lightbox opened
+  try {
+    clearInterval(autoSlideshow);
+  } catch (e) {
+    console.log("Lightbox error: " + e)
+  }
+}
+
+// Close the Lightbox
+function closeLightbox(id) {
+  document.getElementById(lightbox_baseid + id).style.display = "none";
+}
+
+// Move lightbox to the specified item
+function openLightboxItem(id, n) {
+  showItem(lightbox_baseid, id, imageIndex[id] = n, ".snap-lightbox-inner");
+}
+
+// Next/previous controls for lightbox
+function moveLightboxItem(id, n) {
+  showItem(lightbox_baseid, id, imageIndex[id] += n, ".snap-lightbox-inner");
+}
+
+// Next/previous controls for slideshow
+function moveSlideshowItem(id, n, mode) {
+  showItem(slideshow_baseid, id, imageIndex[id] += n, ".snap-image");
+
+  // Kill automatic slideshow once the slideshow has been moved manually
+  if (mode !== "auto") {
+    clearInterval(autoSlideshow);
+  }
+}
+
+// In the slideshow or lightbox, make a specific image visible, make others hidden
+function showItem(baseId, id, n, className) {
+  // Get elements that shall be rotated
+  const element = document.getElementById(baseId + id);
+  const items = element.querySelectorAll(className);
+
+  // Increment item index
+  const updateIndex = () => {
+    if (n > items.length) {
+      imageIndex[id] = 1;
+    }
+    if (n < 1) {
+      imageIndex[id] = items.length;
+    }
+  };
+
+  // hide all selected elements
+  const hideAllItems = () => {
+    for (let i = 0; i < items.length; i++) {
+      items[i].style.display = "none";
+    }
+  };
+
+  // make desired item visible
+  const showCurrentItem = () => {
+    items[imageIndex[id] - 1].style.display = "inline-block";
+  };
+
+  updateIndex();
+  hideAllItems();
+  showCurrentItem();
+}

theme.yaml

@@ -1,17 +1,16 @@
-# SPDX-FileCopyrightText: 2019 Li-Wen Yip <liwen.yip@gmail.com>
 # SPDX-FileCopyrightText: 2019 Max Mehl <mail@mehl.mx>
 # SPDX-License-Identifier: MIT
 
 name: Snap Gallery
 license: MIT
 licenselink: https://src.mehl.mx/mxmehl/hugo-snap-gallery/src/branch/master/LICENSES/MIT.txt
-description: Automagical css image gallery in Hugo using shortcodes. Fork of https://github.com/liwenyip/hugo-easy-gallery
+description: Advanced image gallery using shortcodes. It offers a lightbox and is also usable for single images. CSS only, no Javascript!
 homepage: https://src.mehl.mx/mxmehl/hugo-snap-gallery
 tags:
   - component
 features:
   - gallery
-min_version: 0.50.0
+min_version: 0.60.0
 
 author:
   name: Max Mehl