1 files changed, 77 insertions, 0 deletions
diff --git a/_posts/_posts.11tydata.js b/_posts/_posts.11tydata.js
new file mode 100644
index 0000000..2e07a0e
--- /dev/null
+++ b/_posts/_posts.11tydata.js
@@ -0,0 +1,77 @@
+import markdownIt from "markdown-it";
+const md = markdownIt();
+
+export default {
+  layout: "default",
+  tags: "post",
+  permalink:
+    "/{{ page.date | date: '%Y/%m/%d', 'Etc/UTC' }}/{{ page.fileSlug }}.html",
+  showDate: true,
+  eleventyComputed: {
+    description: async (data) => {
+      if (data.description !== undefined && data.description !== "")
+        return data.description.trim();
+      if (data.page.rawInput === undefined) return null;
+      const markdownAST = md.parse(data.page.rawInput, {});
+      let firstParagraph = "";
+      let skippingBlockquote = false;
+      let skippingStrikethrough = false;
+      extractParagraph: for (const astNode of markdownAST) {
+        if (skippingBlockquote) {
+          if (astNode.type === "blockquote_close") skippingBlockquote = false;
+          continue;
+        }
+        switch (astNode.type) {
+          case "paragraph_open":
+            continue;
+          case "inline":
+            for (const child of astNode.children) {
+              if (skippingStrikethrough) {
+                if (child.type === "s_close") {
+                  skippingStrikethrough = false;
+                  // hopefully this is just never wrong
+                  if (firstParagraph.endsWith(" ")) {
+                    firstParagraph = firstParagraph.replace(/ $/, "");
+                  }
+                }
+                continue;
+              }
+              switch (child.type) {
+                case "text":
+                  firstParagraph += child.content;
+                  break;
+                case "softbreak":
+                  firstParagraph += " ";
+                  break;
+                case "link_open":
+                case "link_close":
+                case "em_open":
+                case "em_close":
+                case "strong_open":
+                case "strong_close":
+                  break;
+                case "s_open":
+                  skippingStrikethrough = true;
+                  break;
+                default:
+                  console.log(data.page.fileSlug, "inline", child);
+              }
+            }
+            break;
+          case "paragraph_close":
+            break extractParagraph;
+          case "blockquote_open":
+            skippingBlockquote = true;
+            break;
+          case "ordered_list_open":
+            throw TypeError(
+              `Can't auto-generate description for ${data.page.inputPath} - starts with list`,
+            );
+          default:
+            console.log(data.page.fileSlug, "block", astNode);
+        }
+      }
+      return firstParagraph;
+    },
+  },
+};