content: generateChronologyLinks, generatePreviousNextLinks

1 files changed, 19 insertions, 0 deletions

diff --git a/src/content/util/getChronologyRelations.js b/src/content/util/getChronologyRelations.js
new file mode 100644
index 0000000..cdfdef3
--- /dev/null
+++ b/src/content/util/getChronologyRelations.js
@@ -0,0 +1,19 @@
+export default function getChronologyRelations(thing, {
+  contributions,
+  linkArtist,
+  linkThing,
+  getThings,
+}) {
+  return contributions.map(({who}) => {
+    const things = getThings(who);
+    const index = things.indexOf(thing);
+    const previous = things[index - 1];
+    const next = things[index + 1];
+    return {
+      index: index + 1,
+      artistLink: linkArtist(who),
+      previousLink: previous ? linkThing(previous) : null,
+      nextLink: next ? linkThing(next) : null,
+    };
+  });
+}