1 files changed, 21 insertions, 4 deletions

diff --git a/scripts/metadata_filter.lua b/scripts/metadata_filter.lua
index d7116dc..cd0c2f7 100644
--- a/scripts/metadata_filter.lua
+++ b/scripts/metadata_filter.lua
@@ -183,20 +183,28 @@ function organize_subpages(site_url, output_dir, ref_file, pages)
                                pandoc.utils.stringify(page.file_out))
     end
 
-    local grouped_pages = group_by(pages, function(p) return not p.date end)
+    local pages_grouped_date =
+        group_by(pages, function(p) return not p.date end)
 
-    local pages_undated = grouped_pages[true] or pandoc.MetaList({})
+    local pages_undated = pages_grouped_date[true] or pandoc.MetaList({})
     pages_undated:sort(function(p1, p2)
         return pandoc.utils.stringify(p1.title) <
                    pandoc.utils.stringify(p2.title)
     end)
 
-    local pages_dated = grouped_pages[false] or pandoc.MetaList({})
+    local pages_dated = pages_grouped_date[false] or pandoc.MetaList({})
     pages_dated:sort(function(p1, p2)
         return pandoc.utils.stringify(p1.date.yyyy_mm_dd) >
                    pandoc.utils.stringify(p2.date.yyyy_mm_dd)
     end)
 
+    local pages_categorized = pages:filter(
+                                  function(p) return p.category ~= nil end)
+    pages_categorized:sort(function(p1, p2)
+        return pandoc.utils.stringify(p1.title) >
+                   pandoc.utils.stringify(p2.title)
+    end)
+
     local pages_by_year = group_by(pages_dated, function(p)
         return pandoc.utils.stringify(p.date.yyyy)
     end)
@@ -205,14 +213,23 @@ function organize_subpages(site_url, output_dir, ref_file, pages)
         return i1.key > i2.key
     end))
 
+    local pages_by_category = group_by(pages_categorized, function(p)
+        return pandoc.utils.stringify(p.category.id)
+    end)
+    pages_by_category = pandoc.MetaList(table_to_list(pages_by_category,
+                                                      function(i1, i2)
+        return i1.key > i2.key
+    end))
+
     local pages_data = pandoc.MetaMap({
         all_dated = pages_dated,
         all_undated = pages_undated,
         by_year = pages_by_year,
+        by_category = pages_by_category,
         last_update = #pages_dated ~= 0 and pages_dated[1].last_update
     })
 
-    local categories_data = group_by(pages_dated, function(p)
+    local categories_data = group_by(pages_categorized, function(p)
         return p.category and pandoc.utils.stringify(p.category.id)
     end, function(stats, _, p)
         if not stats then