From 762344b5da05df672a99498cd281b73fa1964843 Mon Sep 17 00:00:00 2001
From: zyl <z@zyl.gay>
Date: Wed, 13 Nov 2024 11:09:12 -0800
Subject: [PATCH] implement cdn prefix for embed metadata images

---
 site/pages/docs/pages.md | 2 ++
 src/builder.rs           | 9 +++++----
 src/resource.rs          | 9 ++++++---
 3 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/site/pages/docs/pages.md b/site/pages/docs/pages.md
index 7e34da8..cf4aa48 100644
--- a/site/pages/docs/pages.md
+++ b/site/pages/docs/pages.md
@@ -59,6 +59,8 @@ the embed's description. optional.
 
 full url to an image to use for the embed. optional.
 
+prefixing a url with `cdn$` will join it with the site's cdn url as defined in the site config.
+
 #### `theme_color`
 
 the theme color to use for the embed. optional, but the default is currently nonconfigurable.
diff --git a/src/builder.rs b/src/builder.rs
index f7dd083..491c476 100644
--- a/src/builder.rs
+++ b/src/builder.rs
@@ -287,10 +287,11 @@ impl SiteBuilder {
 			_ => self.site.config.title.clone(),
 		};
 
-		let head = page_metadata.embed.map(|mut embed| {
-			embed.site_name.clone_from(&self.site.config.title);
-			embed.build(self)
-		});
+		let head = if let Some(embed) = page_metadata.embed {
+			Some(embed.build(self)?)
+		} else {
+			None
+		};
 
 		let out = self.tera.render(
 			&page_metadata
diff --git a/src/resource.rs b/src/resource.rs
index bf78af2..7594c2a 100644
--- a/src/resource.rs
+++ b/src/resource.rs
@@ -81,7 +81,7 @@ pub struct EmbedMetadata {
 
 impl EmbedMetadata {
 	/// builds the embed html tags
-	pub fn build(self, builder: &SiteBuilder) -> String {
+	pub fn build(self, builder: &SiteBuilder) -> eyre::Result<String> {
 		let mut s = format!(
 			r#"<meta content="{}" property="og:title"><meta content="{}" property="og:url">"#,
 			self.title, builder.site.config.base_url
@@ -93,7 +93,10 @@ impl EmbedMetadata {
 		if let Some(description) = self.description {
 			s = format!(r#"{s}<meta content="{description}" property="og:description">"#);
 		}
-		if let Some(image) = self.image {
+		if let Some(mut image) = self.image {
+			if image.starts_with("cdn$") {
+				image = builder.site.config.cdn_url(&image[4..])?.to_string();
+			}
 			s = format!(r#"{s}<meta content="{image}" property="og:image">"#);
 		}
 		s = format!(
@@ -104,7 +107,7 @@ impl EmbedMetadata {
 			s = format!(r#"{s}<meta name="twitter:card" content="summary_large_image">"#);
 		}
 
-		s
+		Ok(s)
 	}
 
 	pub fn default_theme_color() -> String {