Working, but not finished.

project.clj

@@ -52,6 +52,7 @@
                        [vega-embed "6.2.2"]
                        [vega-lite "4.1.1"]
                        [mermaid "8.4.6"]
+                       [photoswipe "4.1.3"]
                        [tablesort "5.2.0"]]
         :root "resources/public/vendor"}
 

resources/config.edn

@@ -34,7 +34,8 @@
   :formatters           {"vega"         smeagol.formatting/process-vega
                          "vis"          smeagol.formatting/process-vega
                          "mermaid"      smeagol.extensions.mermaid/process-mermaid
-                         "backticks"    smeagol.formatting/process-backticks}
+                         "backticks"    smeagol.formatting/process-backticks
+                         "pswp"         smeagol.formatting/process-photoswipe}
   :log-level            :info           ;; the minimum logging level; one of
                                         ;; :trace :debug :info :warn :error :fatal
   :js-from              :cloudflare     ;; where to load JavaScript libraries

resources/public/content/Example gallery.md

@@ -0,0 +1,59 @@
+## The Gallery
+
+This page holds an example Photoswipe gallery.
+
+```pswp
+{
+  slides: [
+    { src: 'content/uploads/g1.jpg', w: 2592, h:1944,
+      title: 'Frost on a gate, Laurieston' },
+    { src: 'content/uploads/g2.jpg', w: 2560, h:1920,
+      title: 'Feathered crystals on snow surface, Taliesin' },
+    { src: 'content/uploads/g3.jpg', w: 2560, h:1920,
+      title: 'Feathered snow on log, Taliesin' },
+    { src: 'content/uploads/g4.jpg', w: 2560, h:1920,
+      title: 'Crystaline growth on seed head, Taliesin' }],
+	options: {
+      timeToIdle: 100
+			},
+	openImmediately: true
+}
+
+```
+
+## How this works
+
+The specification for this gallery is as follows:
+
+```
+{
+  slides: [
+    { src: 'content/uploads/g1.jpg', w: 2592, h:1944,
+      title: 'Frost on a gate, Laurieston' },
+    { src: 'content/uploads/g2.jpg', w: 2560, h:1920,
+      title: 'Feathered crystals on snow surface, Taliesin' },
+    { src: 'content/uploads/g3.jpg', w: 2560, h:1920,
+      title: 'Feathered snow on log, Taliesin' },
+    { src: 'content/uploads/g4.jpg', w: 2560, h:1920,
+      title: 'Crystaline growth on seed head, Taliesin' }],
+	options: {
+      timeToIdle: 100
+			},
+	openImmediately: true
+}
+
+```
+
+The format of the specification is [JSON](https://www.json.org/json-en.html); there are (at present) three keys, as follows
+
+### slides
+
+Most be present. The value of `slides` is a list delimited by square brackets of slide objects. For more information, see the [authoritative documentation](https://photoswipe.com/documentation/getting-started.html) under the sub heading **'Creating an Array of Slide Objects'**.
+
+### options
+
+Optional. The value of `options` is a JSON object [as documented here](https://photoswipe.com/documentation/options.html).
+
+### openImmediately
+
+Optional. If the value of `openImmediately` is `true`, the gallery will open immediately, covering the whole page. If false, only a button with the label 'Open the gallery' will be shown. Selecting this button will cause the gallery to open.

resources/public/content/Extensible Markup.md

@@ -66,6 +66,12 @@ Mermaid graph specifications can also be loaded from URLs. Here's another exampl
 data/classes.mermaid
 ```
 
+## Photoswipe galleries
+
+Not so much a formatter, this is an extension to allow you to embed image galleries in your markdown. To specify a gallery, use three backticks followed by `pswp`, followed on the following lines by a Photoswipe specification in [JSON](https://www.json.org/json-en.html)
+followed by three backticks on a line by themselves. There is an [[Example gallery]] so that you can see how this works.
+
+
 ## Writing your own custom formatters
 
 A custom formatter is simply a Clojure function which takes a string and an integer as arguments and produces a string as output. The string is the text the user has typed into their markdown; the integer is simply a number you can use to keep track of which addition to the page this is, in order, for example, to fix up some JavaScript to render it.

resources/public/html-includes/photoswipe-boilerplate.html

@@ -0,0 +1,65 @@
+<!-- this is the whole of the photoswipe boilerplate as documented
+    [here](https://photoswipe.com/documentation/getting-started.html) with the
+    outermost div removed; it is supplied by the function
+    `smeagol.extensions.photoswipe/photoswipe-processor`, q.v. -->
+    <!-- Background of PhotoSwipe.
+         It's a separate element as animating opacity is faster than rgba(). -->
+    <div class="pswp__bg"></div>
+
+    <!-- Slides wrapper with overflow:hidden. -->
+    <div class="pswp__scroll-wrap">
+
+        <!-- Container that holds slides.
+            PhotoSwipe keeps only 3 of them in the DOM to save memory.
+            Don't modify these 3 pswp__item elements, data is added later on. -->
+        <div class="pswp__container">
+            <div class="pswp__item"></div>
+            <div class="pswp__item"></div>
+            <div class="pswp__item"></div>
+        </div>
+
+        <!-- Default (PhotoSwipeUI_Default) interface on top of sliding area. Can be changed. -->
+        <div class="pswp__ui pswp__ui--hidden">
+
+            <div class="pswp__top-bar">
+
+                <!--  Controls are self-explanatory. Order can be changed. -->
+
+                <div class="pswp__counter"></div>
+
+                <button class="pswp__button pswp__button--close" title="Close (Esc)"></button>
+
+                <button class="pswp__button pswp__button--share" title="Share"></button>
+
+                <button class="pswp__button pswp__button--fs" title="Toggle fullscreen"></button>
+
+                <button class="pswp__button pswp__button--zoom" title="Zoom in/out"></button>
+
+                <!-- Preloader demo https://codepen.io/dimsemenov/pen/yyBWoR -->
+                <!-- element will get class pswp__preloader--active when preloader is running -->
+                <div class="pswp__preloader">
+                    <div class="pswp__preloader__icn">
+                      <div class="pswp__preloader__cut">
+                        <div class="pswp__preloader__donut"></div>
+                      </div>
+                    </div>
+                </div>
+            </div>
+
+            <div class="pswp__share-modal pswp__share-modal--hidden pswp__single-tap">
+                <div class="pswp__share-tooltip"></div>
+            </div>
+
+            <button class="pswp__button pswp__button--arrow--left" title="Previous (arrow left)">
+            </button>
+
+            <button class="pswp__button pswp__button--arrow--right" title="Next (arrow right)">
+            </button>
+
+            <div class="pswp__caption">
+                <div class="pswp__caption__center"></div>
+            </div>
+
+        </div>
+
+    </div>

resources/public/vendor/README.md

@@ -1 +0,0 @@
-This folder must exist in order that the Bower package manager can deploy JavaScript packages to it.

resources/templates/wiki.html

@@ -2,6 +2,10 @@
 
 {% block extra-headers %}
   <!-- ifequal js-from ":cloudflare" -->
+  {% script "https://cdnjs.cloudflare.com/ajax/libs/photoswipe/4.1.3/photoswipe-ui-default.min.js" %}
+  {% script "https://cdnjs.cloudflare.com/ajax/libs/photoswipe/4.1.3/photoswipe.min.js" %}
+  {% style "vendor/node_modules/photoswipe/dist/photoswipe.css" %}
+  {% style "vendor/node_modules/photoswipe/dist/default-skin/default-skin.css" %}
     <script src="https://cdnjs.cloudflare.com/ajax/libs/mermaid/8.4.6/mermaid.min.js"></script>
     <script src="https://cdnjs.cloudflare.com/ajax/libs/vega/5.9.1/vega.min.js"></script>
     <script src="https://cdnjs.cloudflare.com/ajax/libs/vega-lite/4.1.1/vega-lite.min.js"></script>

src/smeagol/extensions/vega.clj

@@ -1,7 +1,9 @@
 (ns ^{:doc "Format Semagol's extended markdown format."
       :author "Simon Brooke"}
   smeagol.extensions.vega
-  (:require [smeagol.extensions.utils :refer :all]
+  (:require [clojure.data.json :as json]
+            [clj-yaml.core :as yaml]
+            [smeagol.extensions.utils :refer :all]
             [taoensso.timbre :as log]))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -60,6 +62,11 @@
 ;;;;
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
+(defn yaml->json
+  "Rewrite this string, assumed to be in YAML format, as JSON."
+  [^String yaml-src]
+  (json/write-str (yaml/parse-string yaml-src)))
+
 (defn process-vega
   "If this `src-resource-or-url` is a valid URL, it is assumed to point to a
   plain text file pointing to  valid `vega-src`; otherwise, it is expected to
@@ -68,7 +75,7 @@
   Process this `vega-src` string, assumed to be in YAML format, into a
   specification of a Vega chart, and add the plumbing to render it."
   [^String src-resource-or-url ^Integer index]
-  (let [data (resource-url-or-data->data url-or-graph-spec)
+  (let [data (resource-url-or-data->data src-resource-or-url)
         vega-src (:data data)]
     (log/info "Retrieved vega-src from " (:from data) " `" ((:from data) data) "`")
     (str

src/smeagol/formatting.clj

@@ -6,6 +6,7 @@
             [cemerick.url :refer (url url-encode url-decode)]
             [clj-yaml.core :as yaml]
             [markdown.core :as md]
+            [noir.io :as io] ;; used by photoswipe, only
             [smeagol.configuration :refer [config]]
             [smeagol.extensions.mermaid :refer [process-mermaid]]))
 
@@ -85,7 +86,27 @@
     index
     ");\n//]]\n</script>"))
 
-
+(defn process-photoswipe
+  "Process specification for a photoswipe gallery"
+  [^String spec ^Integer index]
+  (str
+    "<div class=\"pswp\" id=\"pswp-"
+    index "\" tabindex=\"-1\" role=\"dialog\" aria-hidden=\"true\">\n"
+    (slurp (str (io/resource-path) "html-includes/photoswipe-boilerplate.html"))
+    "</div>
+    <script>
+    \n//<![CDATA[\n
+    var pswpElement = document.getElementById('pswp-" index "');
+    var spec" index " = "
+    spec
+    ";
+    var gallery" index
+    " = new PhotoSwipe( pswpElement, PhotoSwipeUI_Default, spec" index ".slides, spec" index ".options);
+    if (spec" index ".openImmediately) { gallery" index ".init(); }
+    \n//]]\n
+    </script>
+    <p><button onclick=\"gallery" index ".init()\">Open the gallery</button></p>
+    </div>"))
 
 
 (defn process-backticks