1 files changed, 76 insertions, 0 deletions
diff --git a/app/History/Scramble.hs b/app/History/Scramble.hs
new file mode 100644
index 0000000..9004dbf
--- /dev/null
+++ b/app/History/Scramble.hs
@@ -0,0 +1,76 @@
+module History.Scramble
+  ( Scramble (..),
+    getIssuesOfFile,
+    fromComment,
+  )
+where
+
+import CMark qualified as D
+import Comment qualified as G
+import Control.Exception (Handler (..), catches)
+import Data.Binary (Binary)
+import Data.Digest.Pure.SHA qualified as S
+import Data.Map qualified as M
+import Data.Maybe (catMaybes)
+import Data.Text qualified as T
+import Data.Text.Lazy qualified as LT
+import Data.Text.Lazy.Encoding qualified as LT
+import Exception qualified as E
+import GHC.Generics (Generic)
+import Git qualified
+import Issue qualified as I
+import Issue.Parser qualified as I
+import Issue.Tag qualified as I
+import Issue.Text qualified as I
+import Parallel (parMapM)
+import Render qualified as P
+
+-- | `Scramble` records the complete issues ONLY in files that have
+-- been changed in the commit.
+data Scramble = Scramble
+  { commitHash :: Git.CommitHash,
+    filesChanged :: [FilePath],
+    issues :: M.Map T.Text I.Issue
+  }
+  deriving (Show, Binary, Generic)
+
+-- | Get all issues in the given directory and file.
+getIssuesOfFile :: Git.CommitHash -> FilePath -> IO [I.Issue]
+getIssuesOfFile commitHash filename =
+  ( fmap catMaybes . parMapM (fromComment commitHash)
+      =<< G.getComments commitHash filename
+  )
+    `catches` [ Handler \(_ :: E.UnknownFile) -> pure [],
+                Handler \(_ :: E.UnsupportedLanguage) -> pure []
+              ]
+
+-- | Note that `provenance` is trivial and needs to be fixed up later.
+fromComment :: Git.CommitHash -> G.Comment -> IO (Maybe I.Issue)
+fromComment commitHash comment = do
+  commit <- Git.getCommitOf commitHash
+  let provenance = I.Provenance commit commit
+
+  pure $
+    ( \parseResult ->
+        let (markers, title) =
+              I.stripIssueMarkers (T.pack (show (P.render parseResult.heading)))
+         in I.Issue
+              { commitHash = commitHash,
+                language = comment.language,
+                rawTextHash = S.sha1 (LT.encodeUtf8 (LT.fromStrict rawText)),
+                title = title,
+                file = comment.filePath,
+                provenance = provenance,
+                startByte = comment.startByte,
+                endByte = comment.endByte,
+                startPoint = comment.startPoint,
+                endPoint = comment.endPoint,
+                tags = I.extractTags parseResult.tags,
+                markers = markers,
+                commentStyle = commentStyle,
+                closed = False
+              }
+    )
+      <$> I.parse I.issueMarkers (D.commonmarkToNode [] rawText)
+  where
+    (commentStyle, rawText) = G.uncomment comment.language comment.text