feat: add sorting of affiliations based on research output

This commit adds a sorting functionality to the `getAffiliations` function. The function now calculates the number of documents associated with each affiliation and sorts the affiliations in descending order based on the number of documents. This allows for a more meaningful representation of affiliations based on their research output.

src/app/affiliation/getAffiliations.ts

@@ -1,6 +1,57 @@
-import { authors } from '@/app/db/data'
+import { Document, authors, documents } from '@/app/db/data'
+
+// Interface for the return output
+interface DocumentWithSlug {
+  slug: string
+  doc: Document
+}
+
+const findDocumentsByAuthor = (authorId: string): DocumentWithSlug[] => {
+  // Filter documents by author
+  return Object.entries(documents)
+    .filter(([_, doc]) => doc.manifest.authors.includes(authorId))
+    .map(([slug, doc]) => ({ slug, doc }))
+}
+
+const checkAffiliation = (
+  affiliationStr: string[],
+  affiliationShort: string
+) => {
+  for (const affiliation of affiliationStr) {
+    if (affiliation.split('@')[1] === affiliationShort) {
+      return true
+    }
+  }
+  return false
+}
+
+const getNumberOfDocumentsByAffiliation = (
+  affiliationShort: string
+) => {
+  // Find authors with the given affiliation
+  const results: DocumentWithSlug[] = []
+  for (const [key, value] of Object.entries(authors)) {
+    if (
+      checkAffiliation(value.affiliation, affiliationShort) ||
+      (value.formerAffiliations &&
+        checkAffiliation(value.formerAffiliations, affiliationShort))
+    ) {
+      // Check if document is already in results
+      const additions = findDocumentsByAuthor(key)
+      for (const addition of additions) {
+        const existing = results.find((doc) => doc.slug === addition.slug)
+        if (!existing) {
+          results.push(addition)
+        }
+      }
+    }
+  }
+
+  return results.length
+}
 
 export default function getAffiliations(): string[] {
+  // Get affiliations
   const affiliations: string[] = []
   for (const [_key, value] of Object.entries(authors)) {
     for (const affiliation of value.affiliation) {
@@ -10,5 +61,17 @@ export default function getAffiliations(): string[] {
       }
     }
   }
+
+  // Sort affiliations by research output
+  const affiliationDocs: { [key: string]: number } = {}
+  for (let i = 0; i < affiliations.length; i++) {
+    affiliationDocs[affiliations[i]] = getNumberOfDocumentsByAffiliation(
+      affiliations[i]
+    )
+  }
+  affiliations.sort(
+    (a, b) => affiliationDocs[b] - affiliationDocs[a]
+  )
+
   return affiliations
 }