implement --extract

1 files changed, 55 insertions, 0 deletions

diff --git a/src/MdBlocks/Resolver.hs b/src/MdBlocks/Resolver.hs
new file mode 100644
index 0000000..c6e94d1
--- /dev/null
+++ b/src/MdBlocks/Resolver.hs
@@ -0,0 +1,55 @@
+{-# LANGUAGE OverloadedStrings #-}
+
+module MdBlocks.Resolver
+  ( resolveBlock
+  )
+where
+
+import Data.Text (Text)
+
+import MdBlocks.Address
+import MdBlocks.Types
+
+resolveBlock
+  :: Address
+  -> [Block]
+  -> Maybe Block
+
+resolveBlock (GlobalId ident) blocks =
+  findById ident blocks
+
+resolveBlock (FileAddress fp ident) blocks =
+  findByFileAndId fp ident blocks
+
+findById :: Text -> [Block] -> Maybe Block
+findById ident =
+  go
+  where
+    go [] =
+      Nothing
+
+    go (b:bs)
+      | mdId (blockMeta b) == Just ident =
+          Just b
+
+      | otherwise =
+          go bs
+
+findByFileAndId
+  :: FilePath
+  -> Text
+  -> [Block]
+  -> Maybe Block
+findByFileAndId fp ident =
+  go
+  where
+    go [] =
+      Nothing
+
+    go (b:bs)
+      | blockFile b == fp
+      , mdId (blockMeta b) == Just ident =
+          Just b
+
+      | otherwise =
+          go bs