fixes to posts

contentlayer.config.ts

@@ -6,6 +6,7 @@ import remarkGfm from "remark-gfm"
 
 import { remarkHashtags } from "./src/lib/hashtags"
 import { GenerateSocialImage } from "./src/lib/socialimage"
+import { Post } from "contentlayer/generated"
 
 const hashtagRegex = /#(?<tag>\w+)/g
 
@@ -24,7 +25,7 @@ export const Post = defineDocumentType(() => ({
   computedFields: {
     url: {
       type: "string",
-      resolve: (post) => {
+      resolve: (post: Post) => {
         if (post.draft) {
           return `/api/draft?secret=${process.env.SECRET_TOKEN}&slug=${post.id}`
         }
@@ -33,31 +34,31 @@ export const Post = defineDocumentType(() => ({
     },
     tags: {
       type: "list",
-      resolve: (post) => {
+      resolve: (post: Post) => {
         const match = post.body.raw.match(hashtagRegex)
         if (!match) return []
         const tags = new Set<string>(
-          match.map((m) => m.replace(hashtagRegex, "$<tag>").toLowerCase())
+          match.map((m: string) => m.replace(hashtagRegex, "$<tag>").toLowerCase())
         )
 
         return Array.from(tags)
       },
     },
     social_image: {
       type: "string",
-      resolve: (post) =>
+      resolve: (post: Post) =>
         GenerateSocialImage(
           post.title,
           format(parseISO(post.datetime), "LLLL d, yyyy")
         ),
     },
     readingTime: {
       type: "number",
-      resolve: (post) => readingTime(post.body.raw).minutes,
+      resolve: (post: Post) => readingTime(post.body.raw).minutes,
     },
     wordCount: {
       type: "number",
-      resolve: (post) => readingTime(post.body.raw).words,
+      resolve: (post: Post) => readingTime(post.body.raw).words,
     },
   },
 }))

src/lib/posts.ts

@@ -1,6 +1,7 @@
 import { compareDesc, isFuture } from "date-fns"
+import { notFound } from "next/navigation"
 
-import { allPosts } from "contentlayer/generated"
+import { Post, allPosts } from "contentlayer/generated"
 
 export default function publishedPosts() {
   const posts = allPosts
@@ -10,3 +11,27 @@ export default function publishedPosts() {
 
   return posts
 }
+
+export function previousPost(slug: string) {
+  const posts = publishedPosts()
+  const currentIndex = posts.findIndex((post) => post.id === slug)
+  const previousPost = posts[currentIndex + 1]
+  return previousPost
+}
+
+export function nextPost(slug: string) {
+  const posts = publishedPosts()
+  const currentIndex = posts.findIndex((post) => post.id === slug)
+  const nextPost = posts[currentIndex - 1]
+  return nextPost
+}
+
+export function getPostBySlug(slug: string): Post {
+  const slugNumber = parseInt(slug)
+  const post: Post | undefined = allPosts.find((post) => post.id === slugNumber)
+  if (!post) {
+    notFound()
+  }
+
+  return post
+}