2 files changed, 46 insertions, 0 deletions

diff --git a/scripts/lib/common.lua b/scripts/lib/common.lua
index 80b81ba..5ed3e31 100644
--- a/scripts/lib/common.lua
+++ b/scripts/lib/common.lua
@@ -49,6 +49,16 @@ function pandoc.List:take(n)
     return result
 end
 
+function pandoc.List:skip(n)
+    local result = pandoc.List()
+
+    if n >= #self then return result end
+
+    for i = n + 1, #self do result:insert(self[i]) end
+
+    return result
+end
+
 return {
     dump = dump
 }
diff --git a/scripts/lib/sort.lua b/scripts/lib/sort.lua
new file mode 100644
index 0000000..393e5d5
--- /dev/null
+++ b/scripts/lib/sort.lua
@@ -0,0 +1,36 @@
+local utils = require 'pandoc.utils'
+
+function page_sort(order, pages)
+    order = order and utils.stringify(order)
+
+    return function(ref1, ref2)
+        local p1 = pages and pages[utils.stringify(ref1)] or ref1
+        local p2 = pages and pages[utils.stringify(ref2)] or ref2
+
+        if p1.position then
+            if p2.position then
+                return tonumber(utils.stringify(p1.position)) < tonumber(utils.stringify(p2.position))
+            else
+                return true
+            end
+        elseif p2.position then
+            return false
+        elseif order == "date_desc" then
+            if p1.last_update then
+                if p2.last_update then
+                    return utils.stringify(p1.last_update.yyyy_mm_dd) > utils.stringify(p2.last_update.yyyy_mm_dd)
+                else
+                    return true
+                end
+            else
+                return false
+            end
+        else
+            return utils.stringify(p1.title):upper() < utils.stringify(p2.title):upper()
+        end
+    end
+end
+
+return {
+    page_sort = page_sort
+}