From d0f7ab98fb36a449a68d29e949e0457321def1c6 Mon Sep 17 00:00:00 2001
From: Simon Conseil <contact@saimon.org>
Date: Sat, 6 Mar 2021 12:44:52 -0300
Subject: [PATCH] Custom sort per album

---
 docs/album_information.rst    |  3 +++
 sigal/gallery.py              | 36 ++++++++++++++++++++---------------
 sigal/templates/sigal.conf.py |  7 ++++---
 3 files changed, 28 insertions(+), 18 deletions(-)

diff --git a/docs/album_information.rst b/docs/album_information.rst
index 960528a..4873826 100644
--- a/docs/album_information.rst
+++ b/docs/album_information.rst
@@ -10,6 +10,7 @@ named ``index.md`` :
     Title: Another example gallery
     Thumbnail: test2.jpg
     Author: John Doe
+    Sort: -name
 
     And a description with *Markdown* syntax.
 
@@ -21,6 +22,8 @@ gallery:
   represent the gallery.
 - *Author*: the author of the gallery, if present it is used instead of the
   author setting.
+- *Sort*: the sort order for this album. If prefixed with a '-' it will be in
+  reversed order.
 
 Any additional meta-data is available in the templates. For instance::
 
diff --git a/sigal/gallery.py b/sigal/gallery.py
index 0aa1d6b..f41243d 100644
--- a/sigal/gallery.py
+++ b/sigal/gallery.py
@@ -404,26 +404,32 @@ class Album:
 
     def sort_subdirs(self, albums_sort_attr):
         if self.subdirs:
-            if albums_sort_attr:
-                root_path = self.path if self.path != '.' else ''
-                if albums_sort_attr.startswith("meta."):
-                    meta_key = albums_sort_attr.split(".", 1)[1]
-
-                    def sort_key(s):
-                        album = self.gallery.albums[join(root_path, s)]
-                        return album.meta.get(meta_key, [''])[0]
+            albums_sort_attr = self.settings['albums_sort_attr']
+            reverse = self.settings['albums_sort_reverse']
 
+            if 'sort' in self.meta:
+                albums_sort_attr = self.meta['sort'][0]
+                if albums_sort_attr[0] == '-':
+                    albums_sort_attr = albums_sort_attr[1:]
+                    reverse = True
                 else:
-                    def sort_key(s):
-                        album = self.gallery.albums[join(root_path, s)]
-                        return getattr(album, albums_sort_attr)
+                    reverse = False
+
+            root_path = self.path if self.path != '.' else ''
+            if albums_sort_attr.startswith("meta."):
+                meta_key = albums_sort_attr.split(".", 1)[1]
+
+                def sort_key(s):
+                    album = self.gallery.albums[join(root_path, s)]
+                    return album.meta.get(meta_key, [''])[0]
 
-                key = natsort_keygen(key=sort_key, alg=ns.LOCALE)
             else:
-                key = natsort_keygen(alg=ns.LOCALE)
+                def sort_key(s):
+                    album = self.gallery.albums[join(root_path, s)]
+                    return getattr(album, albums_sort_attr)
 
-            self.subdirs.sort(key=key,
-                              reverse=self.settings['albums_sort_reverse'])
+            key = natsort_keygen(key=sort_key, alg=ns.LOCALE)
+            self.subdirs.sort(key=key, reverse=reverse)
 
         signals.albums_sorted.send(self)
 
diff --git a/sigal/templates/sigal.conf.py b/sigal/templates/sigal.conf.py
index 7518d7a..6230ac3 100644
--- a/sigal/templates/sigal.conf.py
+++ b/sigal/templates/sigal.conf.py
@@ -124,11 +124,12 @@ thumb_size = (280, 210)
 # Use symbolic links instead of copying the original images
 # orig_link = False
 
-# Use symbolic links that are relative to the source directory instead of absolute paths
+# Use symbolic links that are relative to the source directory instead of
+# absolute paths
 # rel_link = False
 
-# Attribute of Album objects which is used to sort medias (eg 'title'). To sort
-# on a metadata key, use 'meta.key'.
+# Attribute of Album objects which is used to sort medias (eg 'title'). To
+# sort on a metadata key, use 'meta.key'.
 # albums_sort_attr = 'name'
 
 # Reverse sort for albums