Add section indexing and update autoref functionality in ChaoDoc module

assets/math-macros.tex

@@ -20,3 +20,4 @@
 \newcommand{\del}{\setminus}
 \newcommand{\con}{/}
 \newcommand{\minor}{\times}
+\newcommand{\FF}{\mathbb{F}}

src/ChaoDoc.hs

@@ -13,6 +13,7 @@ where
 
 import Control.Monad (guard)
 import Control.Monad.State
+import qualified Control.Monad.State.Strict as Strict
 import Data.Char (isSpace)
 import Data.Either
 import Data.Functor
@@ -105,7 +106,8 @@ incrementalBlock =
     "Proposition",
     "Corollary",
     "Observation",
-    "Figure"
+    "Figure",
+    "Table"
   ]
 
 otherBlock :: [Text]
@@ -221,7 +223,41 @@ autoref _ y = y
 autorefFilter :: Pandoc -> Pandoc
 autorefFilter x = walk (autoref links) x
   where
-    links = query theoremIndex x
+    links = query theoremIndex x ++ sectionIndex x
+
+sectionIndex :: Pandoc -> [(Text, (Text, Text))]
+sectionIndex doc = snd $ Strict.execState (walkM collectSectionIndex doc) ([], [])
+
+collectSectionIndex :: Block -> Strict.State ([Int], [(Text, (Text, Text))]) Block
+collectSectionIndex header@(Header level attr@(ident, _, _) _)
+  | isNumberedSectionHeader attr = do
+      (curNums, refs) <- Strict.get
+      let nextNums = nextSectionNumbers level curNums
+          refs'
+            | isSectionIdentifier ident = (ident, ("Section", renderSectionNumber nextNums)) : refs
+            | otherwise = refs
+      Strict.put (nextNums, refs')
+      pure header
+collectSectionIndex block = pure block
+
+isNumberedSectionHeader :: Attr -> Bool
+isNumberedSectionHeader (_, classes, _) = "unnumbered" `notElem` classes
+
+isSectionIdentifier :: Text -> Bool
+isSectionIdentifier = T.isPrefixOf "sec:"
+
+nextSectionNumbers :: Int -> [Int] -> [Int]
+nextSectionNumbers level nums =
+  reverse $ bumpLast $ reverse prefix
+  where
+    prefix = take level (nums ++ repeat 0)
+
+bumpLast :: [Int] -> [Int]
+bumpLast [] = [1]
+bumpLast (x : xs) = (x + 1) : xs
+
+renderSectionNumber :: [Int] -> Text
+renderSectionNumber = T.intercalate "." . map (pack . show)
 
 equationFilter :: Pandoc -> Pandoc
 equationFilter doc = walk (equationAutoref links) processed