[Fix #118] Display Video output with Kindly

Issue: Wolfram may return `(Video <path to file> ...)` and we want to be able to display it nicely in a Clay or compatible notebook.

Fix: Add ns with a fn to try add display metadata to all results, call it from eval.

deps.edn

@@ -34,7 +34,7 @@
            ;; `env CLOJARS_USERNAME=<tbd> CLOJARS_PASSWORD=<clojars-token>  clojure -T:build deploy`
            {:deps {io.github.clojure/tools.build {:git/tag "v0.10.4" :git/sha "31388ff"}
                    slipset/deps-deploy {:mvn/version "0.2.2"}
-                   org.scicloj/clay {:mvn/version "2-beta15"}
+                   org.scicloj/clay {:mvn/version "2-beta17"} ; for the build
                    ;; We need wolframite + JLink to render Wolf code in the docs
                    org.scicloj/wolframite {:local/root "."}
                    wolfram/jlink {:local/root "./symlink-jlink.jar"}} ; FYI jlink only needed for build-site

src/wolframite/core.clj

@@ -41,6 +41,7 @@
    [wolframite.base.package :as package]
    [wolframite.base.parse :as parse]
    [wolframite.impl.jlink-instance :as jlink-instance]
+   [wolframite.impl.kindly-support :as kindly-support]
    [wolframite.impl.protocols :as proto]
    [wolframite.runtime.defaults :as defaults]
    [wolframite.runtime.jlink :as jlink]
@@ -192,7 +193,8 @@
                                  (:opts jlink-inst)
                                  eval-opts)
            expr' (if (string? expr) (express/express expr with-eval-opts) expr)]
-       (cep/cep expr' with-eval-opts))
+       (some-> (cep/cep expr' with-eval-opts)
+               kindly-support/maybe-add-kindly-meta))
      (throw (IllegalStateException. "Not initialized, call start! first")))))
 
 ;; TODO Should we expose this, or will just folks shoot themselves in the foot with it?

src/wolframite/impl/kindly_support.clj

@@ -0,0 +1,20 @@
+(ns wolframite.impl.kindly-support
+  "Add Kindly annotations to eval results to improve their display in compatible tools, such as Clay")
+
+(defn- head [expr]
+  (when (list? expr)
+    (first expr)))
+
+(defn- video->url
+  "Extract the url from `(Video \"url..\" ...)`"
+  [expr]
+  {:pre [(= (head expr) 'Video)]}
+  (second expr))
+
+(defn maybe-add-kindly-meta [expr]
+  {:pre [expr]}
+  (->> (cond
+         (= (head expr) 'Video)
+         {:kind/video true
+          :kindly/options {:kindly/f video->url}})
+       (with-meta expr)))

test/wolframite/core_test.clj

@@ -124,6 +124,18 @@
            (wl/eval "Map[Function[{x}, x + 1],{1,3}]")
            (wl/eval (w/Map (w/fn [x] (w/+ x 1)) [1 3]))))))
 
+(deftest kindly-support
+  (wl/start!)
+  (let [res (wl/eval '(Video "file:///my-fake.mps"))
+        {:keys [kindly/options] :as m}
+        (meta res)
+        view-fn (:kindly/f options)]
+    (is (= 'Video (first res)) "Sanity check: expect Wolfram to return (Video ..)")
+    (is (:kind/video m))
+    (is (= "file:///my-fake.mps" (view-fn res))
+        "Correct metadata is attached, including view fn to extract the video url")))
+
+
 (comment
   (wl/->wl (w/Map (w/fn [] (w/+ (w/Slot 1) 1)) [1 3]))
   (wl/eval (w/Map (w/fn [x] (w/Plus x 1)) [1 2 3]))