add: more SEO meta

More seometa, better markdown parser

app/utils/markdown.ts

@@ -0,0 +1,27 @@
+import type { MinimalElement, MinimalNode } from '@nuxt/content'
+
+type TypedRecord<T extends readonly string[]> = Record<T[number], string>
+
+type PlainText<T extends string[]> = {
+  meta: TypedRecord<T>
+  text: string
+}
+
+const extractText = (element ?: MinimalNode) : string => {
+  if (!element) return ''
+  if (typeof element === 'string') return element
+  const [,, ...nodes] = element
+  return nodes?.map((el : MinimalNode) => typeof el === 'string' ? el : extractText(el)).join(' ') ?? ''
+}
+
+export const generatePlainText = <T extends string[] = []>(body ?: MinimalNode[]) : PlainText<T>[] => {
+  if (!body) return []
+  return body.map<PlainText<T>>(part => {
+    const [, meta] = part as MinimalElement
+    return {
+      meta : meta as TypedRecord<T>,
+      text: extractText(part).replace(/\n/g, ' ')
+    }
+  })
+}
+