get covers from children if no images in album

resources/skel/_templates/album.html

@@ -25,7 +25,7 @@
                     <a href="{{child.name}}/">
                         <div>
                         <img
-                            src="{{child.name}}/{{child.cover_thumbnail_path}}" />
+                            src="{{child.cover_thumbnail_path}}" />
                         </div>
                         <div>
                         {{child.name}}

src/generate.rs

@@ -78,11 +78,16 @@ impl TryFrom<&AlbumDir> for AlbumContext {
             PathBuf::new()
         };
 
-        // Pick a cover image thumbnail and build a path to it
-        // TODO: If album has no images, pick the cover from one of the albums
-        let cover_thumbnail_path = match &album.cover {
-            Some(i) => Path::new("slides").join(&i.thumb_filename),
-            None => PathBuf::from(""),
+        // Make the path to the thumbnail relative to the album that we're in
+        let cover_thumbnail_path: PathBuf;
+        if let Some(parent) = album.path.parent() {
+            cover_thumbnail_path = album.cover.thumb_path.strip_prefix(parent)?.to_path_buf()
+        } else {
+            cover_thumbnail_path = album
+                .cover
+                .thumb_path
+                .strip_prefix(&album.path)?
+                .to_path_buf()
         };
 
         let children: Vec<AlbumContext> = album
@@ -151,9 +156,7 @@ fn generate_images(config: &Config, album: &AlbumDir) -> anyhow::Result<()> {
     let mut all_images: Vec<&Image> = album.iter_all_images().collect();
 
     // also resize cover image
-    if let Some(cover) = &album.cover {
-        all_images.push(cover);
-    }
+    all_images.push(&album.cover);
 
     all_images.par_iter().try_for_each(|img| {
         let orig_image = image::open(&img.path)?;
@@ -162,14 +165,14 @@ fn generate_images(config: &Config, album: &AlbumDir) -> anyhow::Result<()> {
         // image
         //
         // TODO: Hard-link if it's supported, to save on hard drive space
-        let orig_path = output_path.join(&img.path);
+        let full_size_path = output_path.join(&img.path);
         log::info!(
             "Copying original {} -> {}",
             img.path.display(),
-            orig_path.display()
+            full_size_path.display()
         );
-        fs::create_dir_all(orig_path.parent().unwrap_or(Path::new("")))?;
-        orig_image.save(&orig_path)?;
+        fs::create_dir_all(full_size_path.parent().unwrap_or(Path::new("")))?;
+        orig_image.save(&full_size_path)?;
 
         let thumb_path = output_path.join(&img.thumb_path);
         log::info!(

src/generate/album_dir.rs

@@ -11,7 +11,7 @@ use std::slice::Iter;
 pub struct AlbumDir {
     pub path: PathBuf,
     pub images: Vec<Image>,
-    pub cover: Option<Image>,
+    pub cover: Image,
     pub children: Vec<AlbumDir>,
 
     pub description: String,
@@ -99,11 +99,23 @@ impl AlbumDir {
             }
         }
 
-        if cover.is_none() && !images.is_empty() {
-            cover = Some(images[0].clone());
-        }
         // TODO: sort children and albums alphabetically
 
+        // Find a cover image if we didn't have an explicit one. Either the first image, or the
+        // first image from the first album that has a cover.
+        if cover.is_none() {
+            if !images.is_empty() {
+                cover = Some(images[0].clone());
+            } else {
+                // Find a cover image from one of the children
+                if !children.is_empty() {
+                    cover = Some(children[0].cover.clone());
+                }
+            }
+        }
+        let cover = cover.ok_or(anyhow!("Could not find a cover image for {}", p.display()))?;
+        log::debug!("Cover for {} is {cover:?}", p.display());
+
         Ok(AlbumDir {
             path: p.strip_prefix(root)?.to_path_buf(),
             images,