feat: enhance blog post and page schema with new properties

- Added optional `basedOn` field to blog post schema for better content attribution.
- Updated blog post markdown to include `basedOn` reference for improved context.
- Refactored page schema to replace deprecated website schema, enhancing structured data representation.
- Adjusted 404 and index pages to utilize the new page schema for consistency and SEO improvements.

9 files changed, 46 insertions, 27 deletions

diff --git a/src/content/blog/create-lib-file-from-dll.md b/src/content/blog/create-lib-file-from-dll.md
index 472ae23..306c9b7 100644
--- a/src/content/blog/create-lib-file-from-dll.md
+++ b/src/content/blog/create-lib-file-from-dll.md
@@ -1,9 +1,10 @@
 ---
+basedOn: "https://adrianhenke.wordpress.com/2008/12/05/create-lib-file-from-dll/"
 title: 'Create ".lib" file from ".dll" (archive)'
 description: "Learn how to generate a *.lib file from a *.dll with this comprehensive guide. Using the Visual Studio Command Prompt and Microsoft's recommended tools, this article walks you through the steps for a seamless process. Perfect for developers working with 3rd party win dll's."
 datePublished: "2023-05-04"
 dateModified: "2023-05-04"
-author: "Adrian Henke"
+author: "Valentin Popov"
 lang: "en"
 ---
 
diff --git a/src/content/config.ts b/src/content/config.ts
index d7f5f86..916e412 100644
--- a/src/content/config.ts
+++ b/src/content/config.ts
@@ -4,6 +4,7 @@ const blog = defineCollection({
 	type: "content",
 	schema: z.object({
 		author: z.string(),
+		basedOn: z.optional(z.string()),
 		dateModified: z.coerce.date(),
 		datePublished: z.coerce.date(),
 		description: z.string(),
diff --git a/src/pages/404.astro b/src/pages/404.astro
index 072c6e7..cb3fca1 100644
--- a/src/pages/404.astro
+++ b/src/pages/404.astro
@@ -1,15 +1,17 @@
 ---
 import Layout from "../layouts/BaseLayout.astro";
-import websiteSchema from "../utils/schemas/websiteSchema";
+import pageSchema from "../utils/schemas/pageSchema";
 
 const title = "404 — Page Not Found | Valentin Popov";
 const description = "The page you're looking for doesn't exist!";
 const lang = "en";
 
-const schema = websiteSchema({
+const schema = pageSchema({
 	siteUrl: new URL("/", Astro.site).toString(),
+	page: "/404",
 	title,
 	description,
+	lang,
 });
 ---
 
diff --git a/src/pages/blog/[...slug].astro b/src/pages/blog/[...slug].astro
index deb98ac..39207dd 100644
--- a/src/pages/blog/[...slug].astro
+++ b/src/pages/blog/[...slug].astro
@@ -22,15 +22,16 @@ const post = Astro.props;
 
 const { Content, remarkPluginFrontmatter } = await post.render();
 
-const title = post.data.title;
-const description = post.data.description;
 const author = post.data.author;
+const description = post.data.description;
+const isBasedOn = post.data.basedOn;
 const lang = post.data.lang;
+const slug = post.slug;
+const title = post.data.title;
 
-const formattedDate = dayjs(post.data.datePublished.toString()).format("MMMM DD, YYYY");
-const datePublished = post.data.datePublished.toISOString();
 const dateModified = post.data.dateModified?.toISOString();
-const slug = post.slug;
+const datePublished = post.data.datePublished.toISOString();
+const formattedDate = dayjs(post.data.datePublished.toString()).format("MMMM DD, YYYY");
 
 const schema = blogPostSchema({
 	siteUrl: new URL("/", Astro.site).toString(),
@@ -41,6 +42,7 @@ const schema = blogPostSchema({
 	dateModified,
 	author,
 	lang,
+	isBasedOn,
 });
 ---
 
@@ -61,7 +63,6 @@ const schema = blogPostSchema({
 				<small>
 					Posted
 					<time datetime={datePublished} lang="en">{formattedDate}</time>
-					by&nbsp;{author}
 					<span>&nbsp;•&nbsp;</span>
 					<span>{remarkPluginFrontmatter.minutesRead}</span>
 				</small>
diff --git a/src/pages/index.astro b/src/pages/index.astro
index eaa5298..b72c55a 100644
--- a/src/pages/index.astro
+++ b/src/pages/index.astro
@@ -3,16 +3,18 @@ import Layout from "../layouts/BaseLayout.astro";
 import LatestPostsSection from "../components/Sections/LatestPosts.astro";
 import SocialLinksSection from "../components/Sections/SocialLinks.astro";
 import WelcomeSection from "../components/Sections/Welcome.astro";
-import websiteSchema from "../utils/schemas/websiteSchema";
+import pageSchema from "../utils/schemas/pageSchema";
 
 const title = "Valentin Popov – Software Developer & Team Lead | Tech Insights";
 const description = "Blog by Valentin Popov — software developer and team lead writing about code, side projects, digital tools, and fun experiments.";
 const lang = "en";
 
-const schema = websiteSchema({
+const schema = pageSchema({
 	siteUrl: new URL("/", Astro.site).toString(),
+	page: "/",
 	title,
 	description,
+	lang,
 });
 ---
 
diff --git a/src/utils/schemas/blogPostSchema.ts b/src/utils/schemas/blogPostSchema.ts
index 00395dd..9445448 100644
--- a/src/utils/schemas/blogPostSchema.ts
+++ b/src/utils/schemas/blogPostSchema.ts
@@ -5,13 +5,14 @@ export type BlogPostSchemaParams = {
 	readonly dateModified: string;
 	readonly datePublished: string;
 	readonly description: string;
+	readonly isBasedOn?: string;
 	readonly lang: string;
 	readonly siteUrl: string;
 	readonly slug: string;
 	readonly title: string;
 };
 
-export default ({ siteUrl, slug, title, description, datePublished, dateModified, author, lang }: BlogPostSchemaParams): WithContext<BlogPosting> => ({
+export default ({ siteUrl, slug, title, description, datePublished, dateModified, author, lang, isBasedOn }: BlogPostSchemaParams): WithContext<BlogPosting> => ({
 	"@context": "https://schema.org",
 	"@type": "BlogPosting",
 	"url": new URL(`/blog/${slug}`, siteUrl).toString(),
@@ -28,4 +29,5 @@ export default ({ siteUrl, slug, title, description, datePublished, dateModified
 		"@type": "WebPage",
 		"@id": new URL(`/blog/${slug}`, siteUrl).toString(),
 	},
+	...(isBasedOn && { isBasedOn: isBasedOn }),
 });
diff --git a/src/utils/schemas/blogSchema.ts b/src/utils/schemas/blogSchema.ts
index 66a9bae..77f4632 100644
--- a/src/utils/schemas/blogSchema.ts
+++ b/src/utils/schemas/blogSchema.ts
@@ -14,6 +14,8 @@ export default ({ siteUrl, title, posts }: BlogSchemaParams): WithContext<Collec
 	"name": title,
 	"mainEntity": {
 		"@type": "ItemList",
+		"itemListOrder": "https://schema.org/ItemListOrderDescending",
+		"numberOfItems": posts.length,
 		"itemListElement": posts.map((post, index) => ({
 			"@type": "ListItem",
 			"position": index + 1,
diff --git a/src/utils/schemas/pageSchema.ts b/src/utils/schemas/pageSchema.ts
new file mode 100644
index 0000000..606488b
--- /dev/null
+++ b/src/utils/schemas/pageSchema.ts
@@ -0,0 +1,23 @@
+import type { WithContext, WebPage } from "schema-dts";
+
+export type WebsiteSchemaParams = {
+	readonly description: string;
+	readonly page: string;
+	readonly siteUrl: string;
+	readonly title: string;
+	readonly lang: string;
+};
+
+export default ({ siteUrl, page, title, description, lang }: WebsiteSchemaParams): WithContext<WebPage> => ({
+	"@context": "https://schema.org",
+	"@type": "WebPage",
+	"@id": new URL(page, siteUrl).toString(),
+	"url": new URL(page, siteUrl).toString(),
+	"name": title,
+	"description": description,
+	"inLanguage": lang,
+	"mainEntity": {
+		"@type": "WebSite",
+		"@id": new URL("/", siteUrl).toString(),
+	},
+});
diff --git a/src/utils/schemas/websiteSchema.ts b/src/utils/schemas/websiteSchema.ts
deleted file mode 100644
index b971e5e..0000000
--- a/src/utils/schemas/websiteSchema.ts
+++ /dev/null
@@ -1,15 +0,0 @@
-import type { WithContext, WebSite } from "schema-dts";
-
-export type WebsiteSchemaParams = {
-	readonly description: string;
-	readonly siteUrl: string;
-	readonly title: string;
-};
-
-export default ({ siteUrl, title, description }: WebsiteSchemaParams): WithContext<WebSite> => ({
-	"@context": "https://schema.org",
-	"@type": "WebSite",
-	"url": new URL("/", siteUrl).toString(),
-	"name": title,
-	"description": description,
-});