support comments

1 files changed, 29 insertions, 1 deletions

diff --git a/app/Issue/Text.hs b/app/Issue/Text.hs
index 4cfc5f7..cb4ae47 100644
--- a/app/Issue/Text.hs
+++ b/app/Issue/Text.hs
@@ -2,10 +2,12 @@ module Issue.Text
   ( extractText,
     stripIssueMarkers,
     issueMarkers,
+    extractComments,
   )
 where
 
-import Control.Arrow (first, second)
+import CMark qualified as D
+import Control.Arrow (first, second, (***))
 import Data.Text (Text)
 import Data.Text qualified as T
 
@@ -32,3 +34,29 @@ stripIssueMarkers text =
         T.stripStart (T.drop (T.length marker) text)
     [] ->
       ([], text)
+
+extractComments :: T.Text -> ([T.Text], T.Text)
+extractComments text = collect (D.commonmarkToNode [] text)
+  where
+    collect :: D.Node -> ([T.Text], T.Text)
+    collect (D.Node _ D.DOCUMENT ns) =
+      (map (toText . reverse) . reverse)
+        *** (toText . reverse)
+        $ collect' ([], []) ns
+    collect _ = error "commonmarkToNode: no document"
+
+    collect' :: ([[D.Node]], [D.Node]) -> [D.Node] -> ([[D.Node]], [D.Node])
+    collect' (as, rs) [] = (as, rs)
+    collect' ([], rs) (n@(D.Node _ D.PARAGRAPH (n' : _)) : ns)
+      | D.Node _ (D.TEXT s) _ <- n',
+        T.isPrefixOf "COMMENT" s =
+          collect' ([[n]], rs) ns
+      | otherwise = collect' ([], n : rs) ns
+    collect' (ass@(a : as), rs) (n@(D.Node _ D.PARAGRAPH (n' : _)) : ns)
+      | D.Node _ (D.TEXT s) _ <- n',
+        T.isPrefixOf "COMMENT" s =
+          collect' (([n] : ass), rs) ns
+      | otherwise = collect' (((n : a) : as), rs) ns
+    collect' (as, rs) (_ : ns) = collect' (as, rs) ns
+
+    toText = D.nodeToCommonmark [] Nothing . D.Node Nothing D.DOCUMENT