From 370478e7e227c77dc0f58af2730d1daa9e749885 Mon Sep 17 00:00:00 2001
From: clojj <jwin1968@gmail.com>
Date: Sat, 15 Aug 2020 23:26:47 +0200
Subject: [PATCH 01/16] Ok... new with Day

---
 neuron/src/app/Neuron/CLI/New.hs              |  4 +-
 neuron/src/app/Neuron/CLI/Types.hs            |  4 +-
 neuron/src/app/Neuron/Reader/Org.hs           |  5 +-
 neuron/src/app/Neuron/Web/View.hs             |  2 +-
 neuron/src/lib/Neuron/Web/Query/View.hs       |  2 +-
 neuron/src/lib/Neuron/Web/Widget.hs           |  5 +-
 neuron/src/lib/Neuron/Web/Zettel/View.hs      |  2 +-
 neuron/src/lib/Neuron/Zettelkasten/Zettel.hs  |  6 +--
 .../lib/Neuron/Zettelkasten/Zettel/Meta.hs    | 47 ++++++++++++++-----
 .../lib/Neuron/Zettelkasten/Zettel/Parser.hs  |  7 +--
 10 files changed, 53 insertions(+), 31 deletions(-)

diff --git a/neuron/src/app/Neuron/CLI/New.hs b/neuron/src/app/Neuron/CLI/New.hs
index 35e8a365d..4d5157f07 100644
--- a/neuron/src/app/Neuron/CLI/New.hs
+++ b/neuron/src/app/Neuron/CLI/New.hs
@@ -24,7 +24,7 @@ import Neuron.Web.Generate as Gen
 import Neuron.Zettelkasten.ID (zettelIDSourceFileName)
 import qualified Neuron.Zettelkasten.ID.Scheme as IDScheme
 import Neuron.Zettelkasten.Zettel (zettelID)
-import Neuron.Zettelkasten.Zettel.Meta (formatZettelDate)
+import Neuron.Zettelkasten.Zettel.Meta (formatZettelDay)
 import Options.Applicative
 import Relude
 import Rib.Shake (ribInputDir)
@@ -105,6 +105,6 @@ defaultZettelContent format day mtitle = case format of
         "\n"
       ]
   where
-    date = formatZettelDate day
+    date = formatZettelDay day
     defaultTitleName = "Zettel created on " <> date
     title = maybe defaultTitleName T.strip mtitle
diff --git a/neuron/src/app/Neuron/CLI/Types.hs b/neuron/src/app/Neuron/CLI/Types.hs
index 6db648b77..8f9a65184 100644
--- a/neuron/src/app/Neuron/CLI/Types.hs
+++ b/neuron/src/app/Neuron/CLI/Types.hs
@@ -32,7 +32,7 @@ import qualified Neuron.Zettelkasten.Query.Error as Q
 import Neuron.Zettelkasten.Query.Graph as Q
 import qualified Neuron.Zettelkasten.Query.Parser as Q
 import Neuron.Zettelkasten.Zettel as Q
-import Neuron.Zettelkasten.Zettel.Meta (parseZettelDate)
+import Neuron.Zettelkasten.Zettel.Meta (parseZettelDay)
 import Options.Applicative
 import Relude
 import qualified Rib.Cli
@@ -228,4 +228,4 @@ commandParser defaultNotesDir today = do
           Left $ displayException e
     dayReader :: ReadM Day
     dayReader =
-      maybeReader (parseZettelDate . toText)
+      maybeReader (parseZettelDay . toText)
diff --git a/neuron/src/app/Neuron/Reader/Org.hs b/neuron/src/app/Neuron/Reader/Org.hs
index afbcccf24..3e86a8bb1 100644
--- a/neuron/src/app/Neuron/Reader/Org.hs
+++ b/neuron/src/app/Neuron/Reader/Org.hs
@@ -16,9 +16,8 @@ import qualified Data.Map as Map
 import Data.TagTree (Tag (Tag))
 import Data.Tagged
 import Data.Text (toLower)
-import Data.Time.Calendar (Day)
 import Neuron.Reader.Type (ZettelParseError, ZettelReader)
-import Neuron.Zettelkasten.Zettel.Meta (Meta (..), parseZettelDate)
+import Neuron.Zettelkasten.Zettel.Meta (DateMayTime, Meta (..), parseZettelDate)
 import Relude
 import Relude.Extra.Map (lookup)
 import Text.Pandoc (def, runPure)
@@ -44,7 +43,7 @@ extractMetadata doc
     pure $ Just Meta {..}
   | otherwise = pure Nothing
   where
-    parseDate :: Text -> Either ZettelParseError Day
+    parseDate :: Text -> Either ZettelParseError DateMayTime
     parseDate date = maybeToRight (Tagged $ "Invalid date format: " <> date) $ parseZettelDate @Maybe date
 
     parseUnlisted :: Text -> Bool
diff --git a/neuron/src/app/Neuron/Web/View.hs b/neuron/src/app/Neuron/Web/View.hs
index 44d08b3a8..ac82d5b01 100644
--- a/neuron/src/app/Neuron/Web/View.hs
+++ b/neuron/src/app/Neuron/Web/View.hs
@@ -153,7 +153,7 @@ renderSearch graph script = do
       [ "id" .= toJSON zettelID,
         "title" .= zettelTitle,
         "tags" .= zettelTags,
-        "day" .= zettelDay
+        "day" .= zettelDate
       ]
 
 renderBrandFooter :: DomBuilder t m => Maybe Text -> m ()
diff --git a/neuron/src/lib/Neuron/Web/Query/View.hs b/neuron/src/lib/Neuron/Web/Query/View.hs
index 3b1960771..f2edefc4b 100644
--- a/neuron/src/lib/Neuron/Web/Query/View.hs
+++ b/neuron/src/lib/Neuron/Web/Query/View.hs
@@ -104,7 +104,7 @@ renderZettelLink conn (fromMaybe def -> linkView) Zettel {..} = do
           LinkView_Default ->
             Nothing
           LinkView_ShowDate ->
-            elTime <$> zettelDay
+            elTime <$> zettelDate
           LinkView_ShowID ->
             Just $ el "tt" $ text $ zettelIDText zettelID
       classes :: [Text] = catMaybes $ [Just "zettel-link-container"] <> [connClass, rawClass]
diff --git a/neuron/src/lib/Neuron/Web/Widget.hs b/neuron/src/lib/Neuron/Web/Widget.hs
index a4847c8cd..235525f30 100644
--- a/neuron/src/lib/Neuron/Web/Widget.hs
+++ b/neuron/src/lib/Neuron/Web/Widget.hs
@@ -5,13 +5,12 @@
 module Neuron.Web.Widget where
 
 import qualified Data.Text as T
-import Data.Time
-import Neuron.Zettelkasten.Zettel.Meta (formatZettelDate)
+import Neuron.Zettelkasten.Zettel.Meta (DateMayTime, formatZettelDate)
 import Reflex.Dom.Core
 import Relude
 
 -- | <time> element
-elTime :: DomBuilder t m => Day -> m ()
+elTime :: DomBuilder t m => DateMayTime -> m ()
 elTime t = do
   let s = formatZettelDate t
   -- cf. https://developer.mozilla.org/en-US/docs/Web/HTML/Element/time#Attributes
diff --git a/neuron/src/lib/Neuron/Web/Zettel/View.hs b/neuron/src/lib/Neuron/Web/Zettel/View.hs
index 0bba2b724..ae621315c 100644
--- a/neuron/src/lib/Neuron/Web/Zettel/View.hs
+++ b/neuron/src/lib/Neuron/Web/Zettel/View.hs
@@ -119,7 +119,7 @@ renderZettelContent handleLink Zettel {..} = do
     unless zettelTitleInBody $ do
       el "h1" $ text zettelTitle
     void $ elPandoc (Config handleLink) zettelContent
-    whenJust zettelDay $ \day ->
+    whenJust zettelDate $ \day ->
       elAttr "div" ("class" =: "date" <> "title" =: "Zettel creation date") $ do
         text "Created on: "
         elTime day
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel.hs
index 45908ab34..eed5b4384 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel.hs
@@ -26,12 +26,12 @@ import Data.GADT.Show.TH
 import Data.Graph.Labelled (Vertex (..))
 import Data.Some
 import Data.TagTree (Tag, TagPattern (..))
-import Data.Time.Calendar
 import Neuron.Reader.Type
 import Neuron.Zettelkasten.Connection
 import Neuron.Zettelkasten.ID
 import Neuron.Zettelkasten.Query.Error
 import Neuron.Zettelkasten.Query.Theme
+import Neuron.Zettelkasten.Zettel.Meta (DateMayTime)
 import Relude hiding (show)
 import Text.Pandoc.Definition (Pandoc (..))
 import Text.Show (Show (show))
@@ -55,7 +55,7 @@ data ZettelT content = Zettel
     zettelTitle :: Text,
     zettelTitleInBody :: Bool,
     zettelTags :: [Tag],
-    zettelDay :: Maybe Day,
+    zettelDate :: Maybe DateMayTime,
     zettelUnlisted :: Bool,
     zettelQueries :: [Some ZettelQuery],
     zettelError :: ContentError content,
@@ -118,7 +118,7 @@ instance Vertex (ZettelT c) where
 
 sortZettelsReverseChronological :: [Zettel] -> [Zettel]
 sortZettelsReverseChronological =
-  sortOn (Down . zettelDay)
+  sortOn (Down . zettelDate)
 
 deriveJSONGADT ''ZettelQuery
 
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
index 1882c4c54..4fe1f930b 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
@@ -1,4 +1,6 @@
 {-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards #-}
 {-# LANGUAGE TypeApplications #-}
@@ -8,7 +10,10 @@
 module Neuron.Zettelkasten.Zettel.Meta
   ( Meta (..),
     formatZettelDate,
+    formatZettelDay,
     parseZettelDate,
+    parseZettelDay,
+    DateMayTime,
   )
 where
 
@@ -17,12 +22,14 @@ import Data.Time
 import Data.YAML
 import Relude
 
+type DateMayTime = Either Day LocalTime
+
 -- | YAML metadata in a zettel markdown file
 data Meta = Meta
   { title :: Maybe Text,
     tags :: Maybe [Tag],
     -- | Creation day
-    date :: Maybe Day,
+    date :: Maybe DateMayTime,
     -- | List in the z-index
     unlisted :: Maybe Bool
   }
@@ -48,22 +55,38 @@ instance FromYAML Meta where
 --         "date" .= date
 --       ]
 
-instance FromYAML Day where
+instance FromYAML (Either Day LocalTime) where
   parseYAML =
     parseZettelDate <=< parseYAML @Text
 
-instance ToYAML Day where
+instance ToYAML (Either Day LocalTime) where
   toYAML =
     toYAML . formatZettelDate
 
--- | The format in which we decode and encode zettel dates.
-zettelDateFormat :: String
-zettelDateFormat = "%Y-%m-%d"
-
-formatZettelDate :: Day -> Text
+formatZettelDate :: DateMayTime -> Text
 formatZettelDate =
-  toText . formatTime defaultTimeLocale zettelDateFormat
+  toText . \case
+    Left day -> formatTime defaultTimeLocale dateFormat day
+    Right localtime -> formatTime defaultTimeLocale dateTimeFormat localtime
+
+formatZettelDay :: Day -> Text
+formatZettelDay =
+  toText . formatTime defaultTimeLocale dateFormat
+
+parseZettelDate :: MonadFail m => Text -> m DateMayTime
+parseZettelDate t =
+  case (parseTimeM False defaultTimeLocale dateFormat (toString t)) of
+    Just day -> return (Left day)
+    _ -> case (parseTimeM False defaultTimeLocale dateTimeFormat (toString t)) of
+      Just localtime -> return (Right localtime)
+      _ -> fail "no valid date/time"
+
+parseZettelDay :: MonadFail m => Text -> m Day
+parseZettelDay =
+  parseTimeM False defaultTimeLocale dateFormat . toString
+
+dateFormat :: String
+dateFormat = "%Y-%m-%d"
 
-parseZettelDate :: MonadFail m => Text -> m Day
-parseZettelDate =
-  parseTimeM False defaultTimeLocale zettelDateFormat . toString
+dateTimeFormat :: String
+dateTimeFormat = "%Y-%m-%dT%H:%M"
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs
index 4223eeec4..1649a099e 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs
@@ -8,6 +8,7 @@ module Neuron.Zettelkasten.Zettel.Parser where
 import Control.Monad.Writer
 import Data.Some
 import qualified Data.Text as T
+import Data.Time.LocalTime (LocalTime (LocalTime), midday)
 import Neuron.Reader.Type
 import Neuron.Zettelkasten.ID
 import Neuron.Zettelkasten.Query.Error
@@ -37,14 +38,14 @@ parseZettel format zreader fn zid s = do
               ((,True) . plainify . snd <$> getH1 doc)
                 <|> ((,False) . takeInitial . plainify <$> getFirstParagraphText doc)
           tags = fromMaybe [] $ Meta.tags =<< meta
-          day = case zid of
+          date = case zid of
             -- We ignore the "data" meta field on legacy Date IDs, which encode the
             -- creation date in the ID.
-            ZettelDateID v _ -> Just v
+            ZettelDateID v _ -> Just (Right $ LocalTime v midday)
             ZettelCustomID _ -> Meta.date =<< meta
           unlisted = fromMaybe False $ Meta.unlisted =<< meta
           (queries, errors) = runWriter $ extractQueries doc
-       in Right $ Zettel zid format fn title titleInBody tags day unlisted queries errors doc
+       in Right $ Zettel zid format fn title titleInBody tags date unlisted queries errors doc
   where
     -- Extract all (valid) queries from the Pandoc document
     extractQueries :: MonadWriter [QueryParseError] m => Pandoc -> m [Some ZettelQuery]

From db61ef7555adb55c1349b358155b7ae5d94d6d7a Mon Sep 17 00:00:00 2001
From: clojj <jwin1968@gmail.com>
Date: Sun, 16 Aug 2020 00:00:43 +0200
Subject: [PATCH 02/16] new with LocalTime + timeline with days

---
 neuron/src/app/Neuron/CLI.hs                     |  2 +-
 neuron/src/app/Neuron/CLI/New.hs                 | 10 +++++-----
 neuron/src/app/Neuron/CLI/Types.hs               | 10 +++++-----
 neuron/src/lib/Neuron/Web/Query/View.hs          |  3 ++-
 neuron/src/lib/Neuron/Web/Widget.hs              |  6 ++----
 neuron/src/lib/Neuron/Web/Zettel/View.hs         |  3 ++-
 .../src/lib/Neuron/Zettelkasten/Zettel/Meta.hs   | 16 +++++++++++++++-
 7 files changed, 32 insertions(+), 18 deletions(-)

diff --git a/neuron/src/app/Neuron/CLI.hs b/neuron/src/app/Neuron/CLI.hs
index f4308fd7b..e8b129ee2 100644
--- a/neuron/src/app/Neuron/CLI.hs
+++ b/neuron/src/app/Neuron/CLI.hs
@@ -50,7 +50,7 @@ run act = do
       (</> "zettelkasten") <$> getHomeDirectory
     today = do
       tz <- getCurrentTimeZone
-      localDay . utcToLocalTime tz <$> liftIO getCurrentTime
+      utcToLocalTime tz <$> liftIO getCurrentTime
 
 runWith :: (Config -> Action ()) -> App -> IO ()
 runWith act App {..} =
diff --git a/neuron/src/app/Neuron/CLI/New.hs b/neuron/src/app/Neuron/CLI/New.hs
index 4d5157f07..5ae524c1a 100644
--- a/neuron/src/app/Neuron/CLI/New.hs
+++ b/neuron/src/app/Neuron/CLI/New.hs
@@ -24,7 +24,7 @@ import Neuron.Web.Generate as Gen
 import Neuron.Zettelkasten.ID (zettelIDSourceFileName)
 import qualified Neuron.Zettelkasten.ID.Scheme as IDScheme
 import Neuron.Zettelkasten.Zettel (zettelID)
-import Neuron.Zettelkasten.Zettel.Meta (formatZettelDay)
+import Neuron.Zettelkasten.Zettel.Meta
 import Options.Applicative
 import Relude
 import Rib.Shake (ribInputDir)
@@ -56,7 +56,7 @@ newZettelFile NewCommand {..} config = do
       liftIO $ do
         fileAction :: FilePath -> FilePath -> IO () <-
           bool (pure showAction) mkEditActionFromEnv edit
-        writeFileText (notesDir </> zettelFile) $ defaultZettelContent zettelFormat day title
+        writeFileText (notesDir </> zettelFile) $ defaultZettelContent zettelFormat localtime title
         fileAction notesDir zettelFile
   where
     mkEditActionFromEnv :: IO (FilePath -> FilePath -> IO ())
@@ -83,8 +83,8 @@ newZettelFile NewCommand {..} config = do
           if null v then pure Nothing else pure (Just v)
 
 -- TODO use configurable template files?
-defaultZettelContent :: ZettelFormat -> Day -> Maybe Text -> Text
-defaultZettelContent format day mtitle = case format of
+defaultZettelContent :: ZettelFormat -> LocalTime -> Maybe Text -> Text
+defaultZettelContent format now mtitle = case format of
   ZettelFormat_Markdown ->
     T.intercalate
       "\n"
@@ -105,6 +105,6 @@ defaultZettelContent format day mtitle = case format of
         "\n"
       ]
   where
-    date = formatZettelDay day
+    date = formatZettelLocalTime now
     defaultTitleName = "Zettel created on " <> date
     title = maybe defaultTitleName T.strip mtitle
diff --git a/neuron/src/app/Neuron/CLI/Types.hs b/neuron/src/app/Neuron/CLI/Types.hs
index 8f9a65184..da6898a53 100644
--- a/neuron/src/app/Neuron/CLI/Types.hs
+++ b/neuron/src/app/Neuron/CLI/Types.hs
@@ -46,7 +46,7 @@ data App = App
 data NewCommand = NewCommand
   { title :: Maybe Text,
     format :: Maybe ZettelFormat,
-    day :: Day,
+    localtime :: LocalTime,
     idScheme :: Some IDScheme,
     edit :: Bool
   }
@@ -97,8 +97,8 @@ data RibConfig = RibConfig
   deriving (Eq, Show)
 
 -- | optparse-applicative parser for neuron CLI
-commandParser :: FilePath -> Day -> Parser App
-commandParser defaultNotesDir today = do
+commandParser :: FilePath -> LocalTime -> Parser App
+commandParser defaultNotesDir now = do
   notesDir <-
     option
       Rib.Cli.directoryReader
@@ -131,7 +131,7 @@ commandParser defaultNotesDir today = do
         option dayReader $
           long "day"
             <> metavar "DAY"
-            <> value today
+            <> value (localDay now)
             <> showDefault
             <> help "Zettel creation date in UTC"
       -- NOTE: optparse-applicative picks the first option as the default.
@@ -145,7 +145,7 @@ commandParser defaultNotesDir today = do
           <|> fmap
             (const . Some . IDSchemeCustom)
             (option str (long "id" <> help "Use a custom ID" <> metavar "IDNAME"))
-      pure $ New $ NewCommand title format day (idSchemeF day) edit
+      pure $ New $ NewCommand title format now (idSchemeF day) edit
     openCommand = do
       fmap Open $
         fmap
diff --git a/neuron/src/lib/Neuron/Web/Query/View.hs b/neuron/src/lib/Neuron/Web/Query/View.hs
index f2edefc4b..227b53851 100644
--- a/neuron/src/lib/Neuron/Web/Query/View.hs
+++ b/neuron/src/lib/Neuron/Web/Query/View.hs
@@ -34,6 +34,7 @@ import Neuron.Zettelkasten.Connection
 import Neuron.Zettelkasten.ID
 import Neuron.Zettelkasten.Query.Theme (LinkView (..), ZettelsView (..))
 import Neuron.Zettelkasten.Zettel
+import Neuron.Zettelkasten.Zettel.Meta (formatZettelDateAsDay)
 import Reflex.Dom.Core hiding (count, tag)
 import Relude
 
@@ -104,7 +105,7 @@ renderZettelLink conn (fromMaybe def -> linkView) Zettel {..} = do
           LinkView_Default ->
             Nothing
           LinkView_ShowDate ->
-            elTime <$> zettelDate
+            elTime . formatZettelDateAsDay <$> zettelDate
           LinkView_ShowID ->
             Just $ el "tt" $ text $ zettelIDText zettelID
       classes :: [Text] = catMaybes $ [Just "zettel-link-container"] <> [connClass, rawClass]
diff --git a/neuron/src/lib/Neuron/Web/Widget.hs b/neuron/src/lib/Neuron/Web/Widget.hs
index 235525f30..1756cd10d 100644
--- a/neuron/src/lib/Neuron/Web/Widget.hs
+++ b/neuron/src/lib/Neuron/Web/Widget.hs
@@ -5,16 +5,14 @@
 module Neuron.Web.Widget where
 
 import qualified Data.Text as T
-import Neuron.Zettelkasten.Zettel.Meta (DateMayTime, formatZettelDate)
 import Reflex.Dom.Core
 import Relude
 
 -- | <time> element
-elTime :: DomBuilder t m => DateMayTime -> m ()
+elTime :: DomBuilder t m => Text -> m ()
 elTime t = do
-  let s = formatZettelDate t
   -- cf. https://developer.mozilla.org/en-US/docs/Web/HTML/Element/time#Attributes
-  elAttr "time" ("datetime" =: s) $ text s
+  elAttr "time" ("datetime" =: t) $ text t
 
 semanticIcon :: DomBuilder t m => Text -> m ()
 semanticIcon name = elClass "i" (name <> " icon") blank
diff --git a/neuron/src/lib/Neuron/Web/Zettel/View.hs b/neuron/src/lib/Neuron/Web/Zettel/View.hs
index ae621315c..921cf8a17 100644
--- a/neuron/src/lib/Neuron/Web/Zettel/View.hs
+++ b/neuron/src/lib/Neuron/Web/Zettel/View.hs
@@ -28,6 +28,7 @@ import qualified Neuron.Zettelkasten.Graph as G
 import Neuron.Zettelkasten.Query.Error (QueryError, showQueryError)
 import qualified Neuron.Zettelkasten.Query.Eval as Q
 import Neuron.Zettelkasten.Zettel
+import Neuron.Zettelkasten.Zettel.Meta (formatZettelDate)
 import Reflex.Dom.Core hiding ((&))
 import Reflex.Dom.Pandoc
 import Relude hiding ((&))
@@ -122,7 +123,7 @@ renderZettelContent handleLink Zettel {..} = do
     whenJust zettelDate $ \day ->
       elAttr "div" ("class" =: "date" <> "title" =: "Zettel creation date") $ do
         text "Created on: "
-        elTime day
+        elTime $ formatZettelDate day
 
 renderZettelRawContent :: (DomBuilder t m) => ZettelT Text -> m ()
 renderZettelRawContent Zettel {..} = do
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
index 4fe1f930b..e7c30697b 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
@@ -10,6 +10,8 @@
 module Neuron.Zettelkasten.Zettel.Meta
   ( Meta (..),
     formatZettelDate,
+    formatZettelDateAsDay,
+    formatZettelLocalTime,
     formatZettelDay,
     parseZettelDate,
     parseZettelDay,
@@ -69,11 +71,23 @@ formatZettelDate =
     Left day -> formatTime defaultTimeLocale dateFormat day
     Right localtime -> formatTime defaultTimeLocale dateTimeFormat localtime
 
+formatZettelDateAsDay :: DateMayTime -> Text
+formatZettelDateAsDay =
+  toText . \case
+    Left day -> fmt day
+    Right localtime -> fmt (localDay localtime)
+  where
+    fmt = formatTime defaultTimeLocale dateFormat
+
 formatZettelDay :: Day -> Text
 formatZettelDay =
   toText . formatTime defaultTimeLocale dateFormat
 
-parseZettelDate :: MonadFail m => Text -> m DateMayTime
+formatZettelLocalTime :: LocalTime -> Text
+formatZettelLocalTime =
+  toText . formatTime defaultTimeLocale dateTimeFormat
+
+parseZettelDate :: (MonadFail m, Alternative m) => Text -> m DateMayTime
 parseZettelDate t =
   case (parseTimeM False defaultTimeLocale dateFormat (toString t)) of
     Just day -> return (Left day)

From dbdbe6130326c97dd86dc39c4cc04ed78470fa58 Mon Sep 17 00:00:00 2001
From: clojj <jwin1968@gmail.com>
Date: Sun, 16 Aug 2020 00:42:09 +0200
Subject: [PATCH 03/16] fixed Alternative

---
 neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
index e7c30697b..d1f314ac0 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
@@ -89,11 +89,8 @@ formatZettelLocalTime =
 
 parseZettelDate :: (MonadFail m, Alternative m) => Text -> m DateMayTime
 parseZettelDate t =
-  case (parseTimeM False defaultTimeLocale dateFormat (toString t)) of
-    Just day -> return (Left day)
-    _ -> case (parseTimeM False defaultTimeLocale dateTimeFormat (toString t)) of
-      Just localtime -> return (Right localtime)
-      _ -> fail "no valid date/time"
+  let s = toString t
+   in Left <$> parseTimeM False defaultTimeLocale dateFormat s <|> Right <$> parseTimeM False defaultTimeLocale dateTimeFormat s
 
 parseZettelDay :: MonadFail m => Text -> m Day
 parseZettelDay =

From 65b1be61de2c2078ba71c9b7c19a66953b6907a4 Mon Sep 17 00:00:00 2001
From: clojj <jwin1968@gmail.com>
Date: Sun, 16 Aug 2020 09:22:49 +0200
Subject: [PATCH 04/16] cleanups + fix ZettelSpec

---
 neuron/src/app/Neuron/CLI/New.hs                  |  4 ++++
 neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs | 11 +----------
 neuron/test/Neuron/Zettelkasten/ZettelSpec.hs     |  3 ++-
 3 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/neuron/src/app/Neuron/CLI/New.hs b/neuron/src/app/Neuron/CLI/New.hs
index 5ae524c1a..8ca27f934 100644
--- a/neuron/src/app/Neuron/CLI/New.hs
+++ b/neuron/src/app/Neuron/CLI/New.hs
@@ -108,3 +108,7 @@ defaultZettelContent format now mtitle = case format of
     date = formatZettelLocalTime now
     defaultTitleName = "Zettel created on " <> date
     title = maybe defaultTitleName T.strip mtitle
+
+formatZettelLocalTime :: LocalTime -> Text
+formatZettelLocalTime =
+  toText . formatTime defaultTimeLocale dateTimeFormat
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
index d1f314ac0..b82ccd523 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
@@ -9,10 +9,9 @@
 
 module Neuron.Zettelkasten.Zettel.Meta
   ( Meta (..),
+    dateTimeFormat,
     formatZettelDate,
     formatZettelDateAsDay,
-    formatZettelLocalTime,
-    formatZettelDay,
     parseZettelDate,
     parseZettelDay,
     DateMayTime,
@@ -79,14 +78,6 @@ formatZettelDateAsDay =
   where
     fmt = formatTime defaultTimeLocale dateFormat
 
-formatZettelDay :: Day -> Text
-formatZettelDay =
-  toText . formatTime defaultTimeLocale dateFormat
-
-formatZettelLocalTime :: LocalTime -> Text
-formatZettelLocalTime =
-  toText . formatTime defaultTimeLocale dateTimeFormat
-
 parseZettelDate :: (MonadFail m, Alternative m) => Text -> m DateMayTime
 parseZettelDate t =
   let s = toString t
diff --git a/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs b/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
index 8df1a040a..e4067b885 100644
--- a/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
+++ b/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
@@ -8,6 +8,7 @@ module Neuron.Zettelkasten.ZettelSpec
 where
 
 import Data.TagTree
+import Data.Time (LocalTime (LocalTime), midnight)
 import Data.Time.Calendar
 import Neuron.Reader.Markdown
 import Neuron.Reader.Type
@@ -33,7 +34,7 @@ spec = do
             "Some title"
             False
             [Tag "science", Tag "journal/class"]
-            (Just $ mkDay day)
+            (Just (Right $ (LocalTime (mkDay day) midnight)))
             False
             noQueries
             noError

From 2eba1a5a45687377cf22f53323fd6d4d65630bf8 Mon Sep 17 00:00:00 2001
From: clojj <jwin1968@gmail.com>
Date: Sun, 16 Aug 2020 09:49:52 +0200
Subject: [PATCH 05/16] added tag-parsing tests

---
 neuron/src/app/Neuron/Reader/Org.hs  |  7 ++---
 neuron/test/Neuron/Reader/OrgSpec.hs | 38 ++++++++++++++++++++++++++++
 2 files changed, 42 insertions(+), 3 deletions(-)
 create mode 100644 neuron/test/Neuron/Reader/OrgSpec.hs

diff --git a/neuron/src/app/Neuron/Reader/Org.hs b/neuron/src/app/Neuron/Reader/Org.hs
index 3e86a8bb1..40a3526cd 100644
--- a/neuron/src/app/Neuron/Reader/Org.hs
+++ b/neuron/src/app/Neuron/Reader/Org.hs
@@ -9,6 +9,7 @@
 
 module Neuron.Reader.Org
   ( parseOrg,
+    parseDate,
   )
 where
 
@@ -43,8 +44,8 @@ extractMetadata doc
     pure $ Just Meta {..}
   | otherwise = pure Nothing
   where
-    parseDate :: Text -> Either ZettelParseError DateMayTime
-    parseDate date = maybeToRight (Tagged $ "Invalid date format: " <> date) $ parseZettelDate @Maybe date
-
     parseUnlisted :: Text -> Bool
     parseUnlisted a = toLower a == "true"
+
+parseDate :: Text -> Either ZettelParseError DateMayTime
+parseDate date = maybeToRight (Tagged $ "Invalid date format: " <> date) $ parseZettelDate @Maybe date
diff --git a/neuron/test/Neuron/Reader/OrgSpec.hs b/neuron/test/Neuron/Reader/OrgSpec.hs
new file mode 100644
index 000000000..204e99c56
--- /dev/null
+++ b/neuron/test/Neuron/Reader/OrgSpec.hs
@@ -0,0 +1,38 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE NoImplicitPrelude #-}
+
+module Neuron.Reader.OrgSpec
+  ( spec,
+  )
+where
+
+import Data.Tagged (Tagged (Tagged))
+import Data.Time (LocalTime (LocalTime))
+import Data.Time.Calendar
+import Data.Time.LocalTime (TimeOfDay (TimeOfDay))
+import Neuron.Reader.Org
+import Relude
+import Test.Hspec
+
+spec :: Spec
+spec = do
+  describe "date-tag parsing" $ do
+    itParsesDay "with day" "2020-08-16"
+    itParsesDate "with localtime" "2020-08-16T09:42"
+    itParsesInvalid "with invalid" "2020-08-16 09:42"
+
+itParsesDay :: String -> Text -> SpecWith ()
+itParsesDay name s =
+  it name $ do
+    parseDate s `shouldBe` Right (Left (ModifiedJulianDay 59077))
+
+itParsesDate :: String -> Text -> SpecWith ()
+itParsesDate name s =
+  it name $ do
+    parseDate s `shouldBe` Right (Right (LocalTime (ModifiedJulianDay 59077) (TimeOfDay 9 42 0)))
+
+itParsesInvalid :: String -> Text -> SpecWith ()
+itParsesInvalid name s =
+  it name $ do
+    parseDate s `shouldBe` Left (Tagged $ "Invalid date format: " <> s)

From 9411ab33ce0f88191b56027f09c386d23a317770 Mon Sep 17 00:00:00 2001
From: clojj <jwin1968@gmail.com>
Date: Sun, 16 Aug 2020 22:13:34 +0200
Subject: [PATCH 06/16] add sorting tests

---
 neuron/test/Neuron/Zettelkasten/ZettelSpec.hs | 28 +++++++++++++++----
 1 file changed, 22 insertions(+), 6 deletions(-)

diff --git a/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs b/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
index e4067b885..6ff833bcf 100644
--- a/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
+++ b/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
@@ -8,8 +8,9 @@ module Neuron.Zettelkasten.ZettelSpec
 where
 
 import Data.TagTree
-import Data.Time (LocalTime (LocalTime), midnight)
+import Data.Time (LocalTime (LocalTime))
 import Data.Time.Calendar
+import Data.Time.LocalTime (TimeOfDay (TimeOfDay))
 import Neuron.Reader.Markdown
 import Neuron.Reader.Type
 import Neuron.Zettelkasten.ID
@@ -25,8 +26,12 @@ spec = do
       noContent = MetadataOnly ()
   describe "sortZettelsReverseChronological" $ do
     let mkDay = fromGregorian 2020 3
+        mkZettelDay = Just . Left . mkDay
+        mkZettelLocalTime day hh mm = (Just (Right $ (LocalTime (mkDay day) (TimeOfDay hh mm 0))))
+
         (_ :: Maybe Meta, _dummyContent) = either (error . show) id $ parseMarkdown "<spec>" "Dummy"
-        mkZettel day idx =
+
+        mkZettel day date idx =
           Zettel
             (ZettelDateID (mkDay day) idx)
             ZettelFormat_Markdown
@@ -34,12 +39,23 @@ spec = do
             "Some title"
             False
             [Tag "science", Tag "journal/class"]
-            (Just (Right $ (LocalTime (mkDay day) midnight)))
+            date
             False
             noQueries
             noError
             noContent
-    it "sorts correctly" $ do
-      let zs = [mkZettel 3 2, mkZettel 5 1]
+
+    it "sorts correctly with day" $ do
+      let zs = [mkZettel 3 (mkZettelDay 3) 2, mkZettel 5 (mkZettelDay 5) 1]
+      sortZettelsReverseChronological zs
+        `shouldBe` reverse zs
+
+    it "sorts correctly with localtime" $ do
+      let zs = [mkZettel 3 (mkZettelLocalTime 3 9 59) 2, mkZettel 3 (mkZettelLocalTime 3 10 0) 1]
+      sortZettelsReverseChronological zs
+        `shouldBe` reverse zs
+
+    it "sorts correctly with mixed dates" $ do
+      let zs = [mkZettel 3 (mkZettelDay 3) 2, mkZettel 3 (mkZettelLocalTime 3 0 0) 1]
       sortZettelsReverseChronological zs
-        `shouldBe` [mkZettel 5 1, mkZettel 3 2]
+        `shouldBe` reverse zs

From b8dd2ab90bfac3b11fede15ed322d81ea8d6b515 Mon Sep 17 00:00:00 2001
From: clojj <jwin1968@gmail.com>
Date: Mon, 17 Aug 2020 09:29:23 +0200
Subject: [PATCH 07/16] PR 343 changes after review

---
 neuron/src/app/Neuron/CLI.hs                  |  2 +-
 neuron/src/app/Neuron/CLI/New.hs              |  2 +-
 neuron/src/app/Neuron/CLI/Types.hs            | 12 ++++-----
 .../lib/Neuron/Zettelkasten/Zettel/Meta.hs    | 18 ++++++-------
 .../lib/Neuron/Zettelkasten/Zettel/Parser.hs  |  3 +--
 neuron/test/Neuron/Reader/OrgSpec.hs          | 25 ++++++++-----------
 neuron/test/Neuron/Zettelkasten/ZettelSpec.hs |  4 +--
 7 files changed, 29 insertions(+), 37 deletions(-)

diff --git a/neuron/src/app/Neuron/CLI.hs b/neuron/src/app/Neuron/CLI.hs
index e8b129ee2..f4308fd7b 100644
--- a/neuron/src/app/Neuron/CLI.hs
+++ b/neuron/src/app/Neuron/CLI.hs
@@ -50,7 +50,7 @@ run act = do
       (</> "zettelkasten") <$> getHomeDirectory
     today = do
       tz <- getCurrentTimeZone
-      utcToLocalTime tz <$> liftIO getCurrentTime
+      localDay . utcToLocalTime tz <$> liftIO getCurrentTime
 
 runWith :: (Config -> Action ()) -> App -> IO ()
 runWith act App {..} =
diff --git a/neuron/src/app/Neuron/CLI/New.hs b/neuron/src/app/Neuron/CLI/New.hs
index 8ca27f934..758ac2b61 100644
--- a/neuron/src/app/Neuron/CLI/New.hs
+++ b/neuron/src/app/Neuron/CLI/New.hs
@@ -56,7 +56,7 @@ newZettelFile NewCommand {..} config = do
       liftIO $ do
         fileAction :: FilePath -> FilePath -> IO () <-
           bool (pure showAction) mkEditActionFromEnv edit
-        writeFileText (notesDir </> zettelFile) $ defaultZettelContent zettelFormat localtime title
+        writeFileText (notesDir </> zettelFile) $ defaultZettelContent zettelFormat date title
         fileAction notesDir zettelFile
   where
     mkEditActionFromEnv :: IO (FilePath -> FilePath -> IO ())
diff --git a/neuron/src/app/Neuron/CLI/Types.hs b/neuron/src/app/Neuron/CLI/Types.hs
index da6898a53..000fc0359 100644
--- a/neuron/src/app/Neuron/CLI/Types.hs
+++ b/neuron/src/app/Neuron/CLI/Types.hs
@@ -46,7 +46,7 @@ data App = App
 data NewCommand = NewCommand
   { title :: Maybe Text,
     format :: Maybe ZettelFormat,
-    localtime :: LocalTime,
+    date :: LocalTime,
     idScheme :: Some IDScheme,
     edit :: Bool
   }
@@ -97,8 +97,8 @@ data RibConfig = RibConfig
   deriving (Eq, Show)
 
 -- | optparse-applicative parser for neuron CLI
-commandParser :: FilePath -> LocalTime -> Parser App
-commandParser defaultNotesDir now = do
+commandParser :: FilePath -> Day -> Parser App
+commandParser defaultNotesDir today = do
   notesDir <-
     option
       Rib.Cli.directoryReader
@@ -127,11 +127,11 @@ commandParser defaultNotesDir now = do
               <> long "format"
               <> help "The document format of the new zettel"
       edit <- switch (long "edit" <> short 'e' <> help "Open the newly-created zettel in $EDITOR")
-      day <-
+      dayParam <-
         option dayReader $
           long "day"
             <> metavar "DAY"
-            <> value (localDay now)
+            <> value today
             <> showDefault
             <> help "Zettel creation date in UTC"
       -- NOTE: optparse-applicative picks the first option as the default.
@@ -145,7 +145,7 @@ commandParser defaultNotesDir now = do
           <|> fmap
             (const . Some . IDSchemeCustom)
             (option str (long "id" <> help "Use a custom ID" <> metavar "IDNAME"))
-      pure $ New $ NewCommand title format now (idSchemeF day) edit
+      pure $ New $ NewCommand title format (LocalTime dayParam midday) (idSchemeF dayParam) edit
     openCommand = do
       fmap Open $
         fmap
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
index b82ccd523..8fa1b65c5 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
@@ -3,6 +3,7 @@
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE ViewPatterns #-}
 {-# LANGUAGE TypeApplications #-}
 {-# LANGUAGE NoImplicitPrelude #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
@@ -56,11 +57,11 @@ instance FromYAML Meta where
 --         "date" .= date
 --       ]
 
-instance FromYAML (Either Day LocalTime) where
+instance FromYAML DateMayTime where
   parseYAML =
     parseZettelDate <=< parseYAML @Text
 
-instance ToYAML (Either Day LocalTime) where
+instance ToYAML DateMayTime where
   toYAML =
     toYAML . formatZettelDate
 
@@ -72,16 +73,13 @@ formatZettelDate =
 
 formatZettelDateAsDay :: DateMayTime -> Text
 formatZettelDateAsDay =
-  toText . \case
-    Left day -> fmt day
-    Right localtime -> fmt (localDay localtime)
-  where
-    fmt = formatTime defaultTimeLocale dateFormat
+  toText . formatTime defaultTimeLocale dateFormat . \case
+    Left day -> day
+    Right localtime -> localDay localtime
 
 parseZettelDate :: (MonadFail m, Alternative m) => Text -> m DateMayTime
-parseZettelDate t =
-  let s = toString t
-   in Left <$> parseTimeM False defaultTimeLocale dateFormat s <|> Right <$> parseTimeM False defaultTimeLocale dateTimeFormat s
+parseZettelDate (toString -> s) =
+  Left <$> parseTimeM False defaultTimeLocale dateFormat s <|> Right <$> parseTimeM False defaultTimeLocale dateTimeFormat s
 
 parseZettelDay :: MonadFail m => Text -> m Day
 parseZettelDay =
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs
index 1649a099e..2f3b144a5 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs
@@ -8,7 +8,6 @@ module Neuron.Zettelkasten.Zettel.Parser where
 import Control.Monad.Writer
 import Data.Some
 import qualified Data.Text as T
-import Data.Time.LocalTime (LocalTime (LocalTime), midday)
 import Neuron.Reader.Type
 import Neuron.Zettelkasten.ID
 import Neuron.Zettelkasten.Query.Error
@@ -41,7 +40,7 @@ parseZettel format zreader fn zid s = do
           date = case zid of
             -- We ignore the "data" meta field on legacy Date IDs, which encode the
             -- creation date in the ID.
-            ZettelDateID v _ -> Just (Right $ LocalTime v midday)
+            ZettelDateID v _ -> Just $ Left v
             ZettelCustomID _ -> Meta.date =<< meta
           unlisted = fromMaybe False $ Meta.unlisted =<< meta
           (queries, errors) = runWriter $ extractQueries doc
diff --git a/neuron/test/Neuron/Reader/OrgSpec.hs b/neuron/test/Neuron/Reader/OrgSpec.hs
index 204e99c56..fc65caea2 100644
--- a/neuron/test/Neuron/Reader/OrgSpec.hs
+++ b/neuron/test/Neuron/Reader/OrgSpec.hs
@@ -17,22 +17,17 @@ import Test.Hspec
 
 spec :: Spec
 spec = do
+  let itParsesDay name s =
+        it name $ do
+          parseDate s `shouldBe` Right (Left (ModifiedJulianDay 59077))
+      itParsesDate name s =
+        it name $ do
+          parseDate s `shouldBe` Right (Right (LocalTime (ModifiedJulianDay 59077) (TimeOfDay 9 42 0)))
+      itParsesInvalid name s =
+        it name $ do
+          parseDate s `shouldBe` Left (Tagged $ "Invalid date format: " <> s)
+
   describe "date-tag parsing" $ do
     itParsesDay "with day" "2020-08-16"
     itParsesDate "with localtime" "2020-08-16T09:42"
     itParsesInvalid "with invalid" "2020-08-16 09:42"
-
-itParsesDay :: String -> Text -> SpecWith ()
-itParsesDay name s =
-  it name $ do
-    parseDate s `shouldBe` Right (Left (ModifiedJulianDay 59077))
-
-itParsesDate :: String -> Text -> SpecWith ()
-itParsesDate name s =
-  it name $ do
-    parseDate s `shouldBe` Right (Right (LocalTime (ModifiedJulianDay 59077) (TimeOfDay 9 42 0)))
-
-itParsesInvalid :: String -> Text -> SpecWith ()
-itParsesInvalid name s =
-  it name $ do
-    parseDate s `shouldBe` Left (Tagged $ "Invalid date format: " <> s)
diff --git a/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs b/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
index 6ff833bcf..87dbc5a19 100644
--- a/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
+++ b/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
@@ -27,7 +27,7 @@ spec = do
   describe "sortZettelsReverseChronological" $ do
     let mkDay = fromGregorian 2020 3
         mkZettelDay = Just . Left . mkDay
-        mkZettelLocalTime day hh mm = (Just (Right $ (LocalTime (mkDay day) (TimeOfDay hh mm 0))))
+        mkZettelLocalTime day hh mm = Just $ Right $ LocalTime (mkDay day) $ TimeOfDay hh mm 0
 
         (_ :: Maybe Meta, _dummyContent) = either (error . show) id $ parseMarkdown "<spec>" "Dummy"
 
@@ -56,6 +56,6 @@ spec = do
         `shouldBe` reverse zs
 
     it "sorts correctly with mixed dates" $ do
-      let zs = [mkZettel 3 (mkZettelDay 3) 2, mkZettel 3 (mkZettelLocalTime 3 0 0) 1]
+      let zs = [mkZettel 3 (mkZettelDay 5) 2, mkZettel 3 (mkZettelLocalTime 3 0 0) 1]
       sortZettelsReverseChronological zs
         `shouldBe` reverse zs

From c0576b9cd3bf813dbbedffba875d80211662df5c Mon Sep 17 00:00:00 2001
From: clojj <jwin1968@gmail.com>
Date: Mon, 17 Aug 2020 22:36:28 +0200
Subject: [PATCH 08/16] enable both formats for date-option

---
 neuron/src/app/Neuron/CLI/New.hs   | 11 +++--------
 neuron/src/app/Neuron/CLI/Types.hs | 31 +++++++++++++++++-------------
 2 files changed, 21 insertions(+), 21 deletions(-)

diff --git a/neuron/src/app/Neuron/CLI/New.hs b/neuron/src/app/Neuron/CLI/New.hs
index 758ac2b61..06e6d5a70 100644
--- a/neuron/src/app/Neuron/CLI/New.hs
+++ b/neuron/src/app/Neuron/CLI/New.hs
@@ -15,7 +15,6 @@ import qualified Data.Set as Set
 import Data.Some
 import Data.Text (strip)
 import qualified Data.Text as T
-import Data.Time
 import Development.Shake (Action)
 import Neuron.CLI.Types
 import Neuron.Config.Type (Config (..), getZettelFormats)
@@ -83,8 +82,8 @@ newZettelFile NewCommand {..} config = do
           if null v then pure Nothing else pure (Just v)
 
 -- TODO use configurable template files?
-defaultZettelContent :: ZettelFormat -> LocalTime -> Maybe Text -> Text
-defaultZettelContent format now mtitle = case format of
+defaultZettelContent :: ZettelFormat -> DateMayTime -> Maybe Text -> Text
+defaultZettelContent format dmt mtitle = case format of
   ZettelFormat_Markdown ->
     T.intercalate
       "\n"
@@ -105,10 +104,6 @@ defaultZettelContent format now mtitle = case format of
         "\n"
       ]
   where
-    date = formatZettelLocalTime now
+    date = formatZettelDate dmt
     defaultTitleName = "Zettel created on " <> date
     title = maybe defaultTitleName T.strip mtitle
-
-formatZettelLocalTime :: LocalTime -> Text
-formatZettelLocalTime =
-  toText . formatTime defaultTimeLocale dateTimeFormat
diff --git a/neuron/src/app/Neuron/CLI/Types.hs b/neuron/src/app/Neuron/CLI/Types.hs
index 000fc0359..9eeead3be 100644
--- a/neuron/src/app/Neuron/CLI/Types.hs
+++ b/neuron/src/app/Neuron/CLI/Types.hs
@@ -32,7 +32,7 @@ import qualified Neuron.Zettelkasten.Query.Error as Q
 import Neuron.Zettelkasten.Query.Graph as Q
 import qualified Neuron.Zettelkasten.Query.Parser as Q
 import Neuron.Zettelkasten.Zettel as Q
-import Neuron.Zettelkasten.Zettel.Meta (parseZettelDay)
+import Neuron.Zettelkasten.Zettel.Meta (DateMayTime, formatZettelDate, parseZettelDate)
 import Options.Applicative
 import Relude
 import qualified Rib.Cli
@@ -46,7 +46,7 @@ data App = App
 data NewCommand = NewCommand
   { title :: Maybe Text,
     format :: Maybe ZettelFormat,
-    date :: LocalTime,
+    date :: DateMayTime,
     idScheme :: Some IDScheme,
     edit :: Bool
   }
@@ -127,13 +127,13 @@ commandParser defaultNotesDir today = do
               <> long "format"
               <> help "The document format of the new zettel"
       edit <- switch (long "edit" <> short 'e' <> help "Open the newly-created zettel in $EDITOR")
-      dayParam <-
-        option dayReader $
-          long "day"
-            <> metavar "DAY"
-            <> value today
-            <> showDefault
-            <> help "Zettel creation date in UTC"
+      dateParam <-
+        option dateReader $
+          long "date"
+            <> metavar "DATE"
+            <> value (Left today)
+            <> showDefaultWith (toString . formatZettelDate)
+            <> help "Zettel creation date/time"
       -- NOTE: optparse-applicative picks the first option as the default.
       idSchemeF <-
         fmap
@@ -145,7 +145,7 @@ commandParser defaultNotesDir today = do
           <|> fmap
             (const . Some . IDSchemeCustom)
             (option str (long "id" <> help "Use a custom ID" <> metavar "IDNAME"))
-      pure $ New $ NewCommand title format (LocalTime dayParam midday) (idSchemeF dayParam) edit
+      pure $ New $ NewCommand title format dateParam (idSchemeF $ extractDay dateParam) edit
     openCommand = do
       fmap Open $
         fmap
@@ -226,6 +226,11 @@ commandParser defaultNotesDir today = do
           either (Left . toString . Q.showQueryParseError) (maybe (Left "Unsupported query") Right) $ Q.queryFromURI uri
         Left e ->
           Left $ displayException e
-    dayReader :: ReadM Day
-    dayReader =
-      maybeReader (parseZettelDay . toText)
+    dateReader :: ReadM DateMayTime
+    dateReader =
+      maybeReader (parseZettelDate . toText)
+    extractDay :: DateMayTime -> Day
+    extractDay dmt =
+      case dmt of
+        Left day -> day
+        Right lt -> localDay lt
\ No newline at end of file

From 43c682b4a5ace7761f2922dd41fec073c6312ecd Mon Sep 17 00:00:00 2001
From: clojj <jwin1968@gmail.com>
Date: Tue, 18 Aug 2020 11:30:42 +0200
Subject: [PATCH 09/16] default LocalTime for new-command inline functions in
 test

---
 neuron/src/app/Neuron/CLI.hs         |  6 +++---
 neuron/src/app/Neuron/CLI/Types.hs   |  6 +++---
 neuron/test/Neuron/Reader/OrgSpec.hs | 19 ++++++-------------
 3 files changed, 12 insertions(+), 19 deletions(-)

diff --git a/neuron/src/app/Neuron/CLI.hs b/neuron/src/app/Neuron/CLI.hs
index f4308fd7b..98c0b71de 100644
--- a/neuron/src/app/Neuron/CLI.hs
+++ b/neuron/src/app/Neuron/CLI.hs
@@ -34,7 +34,7 @@ import System.FilePath
 
 run :: (Config -> Action ()) -> IO ()
 run act = do
-  cliParser <- commandParser <$> defaultNotesDir <*> today
+  cliParser <- commandParser <$> defaultNotesDir <*> now
   app <-
     execParser $
       info
@@ -48,9 +48,9 @@ run act = do
         (long "version" <> help "Show version")
     defaultNotesDir =
       (</> "zettelkasten") <$> getHomeDirectory
-    today = do
+    now = do
       tz <- getCurrentTimeZone
-      localDay . utcToLocalTime tz <$> liftIO getCurrentTime
+      utcToLocalTime tz <$> liftIO getCurrentTime
 
 runWith :: (Config -> Action ()) -> App -> IO ()
 runWith act App {..} =
diff --git a/neuron/src/app/Neuron/CLI/Types.hs b/neuron/src/app/Neuron/CLI/Types.hs
index 9eeead3be..318b3239c 100644
--- a/neuron/src/app/Neuron/CLI/Types.hs
+++ b/neuron/src/app/Neuron/CLI/Types.hs
@@ -97,8 +97,8 @@ data RibConfig = RibConfig
   deriving (Eq, Show)
 
 -- | optparse-applicative parser for neuron CLI
-commandParser :: FilePath -> Day -> Parser App
-commandParser defaultNotesDir today = do
+commandParser :: FilePath -> LocalTime -> Parser App
+commandParser defaultNotesDir now = do
   notesDir <-
     option
       Rib.Cli.directoryReader
@@ -131,7 +131,7 @@ commandParser defaultNotesDir today = do
         option dateReader $
           long "date"
             <> metavar "DATE"
-            <> value (Left today)
+            <> value (Right now)
             <> showDefaultWith (toString . formatZettelDate)
             <> help "Zettel creation date/time"
       -- NOTE: optparse-applicative picks the first option as the default.
diff --git a/neuron/test/Neuron/Reader/OrgSpec.hs b/neuron/test/Neuron/Reader/OrgSpec.hs
index fc65caea2..87ee95c86 100644
--- a/neuron/test/Neuron/Reader/OrgSpec.hs
+++ b/neuron/test/Neuron/Reader/OrgSpec.hs
@@ -17,17 +17,10 @@ import Test.Hspec
 
 spec :: Spec
 spec = do
-  let itParsesDay name s =
-        it name $ do
-          parseDate s `shouldBe` Right (Left (ModifiedJulianDay 59077))
-      itParsesDate name s =
-        it name $ do
-          parseDate s `shouldBe` Right (Right (LocalTime (ModifiedJulianDay 59077) (TimeOfDay 9 42 0)))
-      itParsesInvalid name s =
-        it name $ do
-          parseDate s `shouldBe` Left (Tagged $ "Invalid date format: " <> s)
-
   describe "date-tag parsing" $ do
-    itParsesDay "with day" "2020-08-16"
-    itParsesDate "with localtime" "2020-08-16T09:42"
-    itParsesInvalid "with invalid" "2020-08-16 09:42"
+    it "with day" $ do
+      parseDate "2020-08-16" `shouldBe` Right (Left (ModifiedJulianDay 59077))
+    it "with localtime" $ do
+      parseDate "2020-08-16T09:42" `shouldBe` Right (Right (LocalTime (ModifiedJulianDay 59077) (TimeOfDay 9 42 0)))
+    it "with invalid" $ do
+      parseDate "2020-08-16 09:42" `shouldBe` Left (Tagged $ "Invalid date format: " <> "2020-08-16 09:42")

From ca655a7df9a3508cce69d71a7c6146ca7931cc11 Mon Sep 17 00:00:00 2001
From: Sridhar Ratnakumar <srid@srid.ca>
Date: Tue, 18 Aug 2020 16:00:20 -0400
Subject: [PATCH 10/16] Up ver, and change cli help

---
 neuron/neuron.cabal                               | 2 +-
 neuron/src/app/Neuron/CLI/Types.hs                | 4 ++--
 neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/neuron/neuron.cabal b/neuron/neuron.cabal
index 0e535a3a8..1d93ebcec 100644
--- a/neuron/neuron.cabal
+++ b/neuron/neuron.cabal
@@ -1,7 +1,7 @@
 cabal-version: 2.4
 name: neuron
 -- This version must be in sync with what's in Default.dhall
-version: 0.6.3.2
+version: 0.6.4.0
 license: AGPL-3.0-only
 copyright: 2020 Sridhar Ratnakumar
 maintainer: srid@srid.ca
diff --git a/neuron/src/app/Neuron/CLI/Types.hs b/neuron/src/app/Neuron/CLI/Types.hs
index 318b3239c..5bcdff657 100644
--- a/neuron/src/app/Neuron/CLI/Types.hs
+++ b/neuron/src/app/Neuron/CLI/Types.hs
@@ -130,7 +130,7 @@ commandParser defaultNotesDir now = do
       dateParam <-
         option dateReader $
           long "date"
-            <> metavar "DATE"
+            <> metavar "DATE/TIME"
             <> value (Right now)
             <> showDefaultWith (toString . formatZettelDate)
             <> help "Zettel creation date/time"
@@ -233,4 +233,4 @@ commandParser defaultNotesDir now = do
     extractDay dmt =
       case dmt of
         Left day -> day
-        Right lt -> localDay lt
\ No newline at end of file
+        Right lt -> localDay lt
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
index 8fa1b65c5..a617a8452 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
@@ -3,8 +3,8 @@
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards #-}
-{-# LANGUAGE ViewPatterns #-}
 {-# LANGUAGE TypeApplications #-}
+{-# LANGUAGE ViewPatterns #-}
 {-# LANGUAGE NoImplicitPrelude #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 

From 07d85952767f9fa69ad738b41dd63dac82a20e85 Mon Sep 17 00:00:00 2001
From: Sridhar Ratnakumar <srid@srid.ca>
Date: Tue, 18 Aug 2020 17:38:26 -0400
Subject: [PATCH 11/16] Make DateMayTime a tuple for straightforward semantics

---
 neuron/src/app/Neuron/CLI/Types.hs            | 17 ++++---
 neuron/src/lib/Neuron/Web/Query/View.hs       |  4 +-
 .../lib/Neuron/Zettelkasten/Zettel/Meta.hs    | 49 +++++++++++++------
 .../lib/Neuron/Zettelkasten/Zettel/Parser.hs  |  2 +-
 neuron/test/Neuron/Zettelkasten/ZettelSpec.hs | 35 ++++++++-----
 5 files changed, 69 insertions(+), 38 deletions(-)

diff --git a/neuron/src/app/Neuron/CLI/Types.hs b/neuron/src/app/Neuron/CLI/Types.hs
index 5bcdff657..e6b8e77ab 100644
--- a/neuron/src/app/Neuron/CLI/Types.hs
+++ b/neuron/src/app/Neuron/CLI/Types.hs
@@ -32,7 +32,13 @@ import qualified Neuron.Zettelkasten.Query.Error as Q
 import Neuron.Zettelkasten.Query.Graph as Q
 import qualified Neuron.Zettelkasten.Query.Parser as Q
 import Neuron.Zettelkasten.Zettel as Q
-import Neuron.Zettelkasten.Zettel.Meta (DateMayTime, formatZettelDate, parseZettelDate)
+import Neuron.Zettelkasten.Zettel.Meta
+  ( DateMayTime,
+    formatZettelDate,
+    getDay,
+    mkDateMayTime,
+    parseZettelDate,
+  )
 import Options.Applicative
 import Relude
 import qualified Rib.Cli
@@ -131,7 +137,7 @@ commandParser defaultNotesDir now = do
         option dateReader $
           long "date"
             <> metavar "DATE/TIME"
-            <> value (Right now)
+            <> value (mkDateMayTime $ Right now)
             <> showDefaultWith (toString . formatZettelDate)
             <> help "Zettel creation date/time"
       -- NOTE: optparse-applicative picks the first option as the default.
@@ -145,7 +151,7 @@ commandParser defaultNotesDir now = do
           <|> fmap
             (const . Some . IDSchemeCustom)
             (option str (long "id" <> help "Use a custom ID" <> metavar "IDNAME"))
-      pure $ New $ NewCommand title format dateParam (idSchemeF $ extractDay dateParam) edit
+      pure $ New $ NewCommand title format dateParam (idSchemeF $ getDay dateParam) edit
     openCommand = do
       fmap Open $
         fmap
@@ -229,8 +235,3 @@ commandParser defaultNotesDir now = do
     dateReader :: ReadM DateMayTime
     dateReader =
       maybeReader (parseZettelDate . toText)
-    extractDay :: DateMayTime -> Day
-    extractDay dmt =
-      case dmt of
-        Left day -> day
-        Right lt -> localDay lt
diff --git a/neuron/src/lib/Neuron/Web/Query/View.hs b/neuron/src/lib/Neuron/Web/Query/View.hs
index f9f14d515..3bdf69be9 100644
--- a/neuron/src/lib/Neuron/Web/Query/View.hs
+++ b/neuron/src/lib/Neuron/Web/Query/View.hs
@@ -32,7 +32,7 @@ import Neuron.Zettelkasten.Connection
 import Neuron.Zettelkasten.ID
 import Neuron.Zettelkasten.Query.Theme (LinkView (..), ZettelsView (..))
 import Neuron.Zettelkasten.Zettel
-import Neuron.Zettelkasten.Zettel.Meta (formatZettelDateAsDay)
+import Neuron.Zettelkasten.Zettel.Meta (formatDay, getDay)
 import Reflex.Dom.Core hiding (count, tag)
 import Relude
 
@@ -103,7 +103,7 @@ renderZettelLink conn (fromMaybe def -> linkView) Zettel {..} = do
           LinkView_Default ->
             Nothing
           LinkView_ShowDate ->
-            elTime . formatZettelDateAsDay <$> zettelDate
+            elTime . formatDay . getDay <$> zettelDate
           LinkView_ShowID ->
             Just $ el "tt" $ text $ zettelIDText zettelID
       classes :: [Text] = catMaybes $ [Just "zettel-link-container"] <> [connClass, rawClass]
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
index a617a8452..3a4d7269b 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
@@ -1,5 +1,6 @@
 {-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards #-}
@@ -12,20 +13,21 @@ module Neuron.Zettelkasten.Zettel.Meta
   ( Meta (..),
     dateTimeFormat,
     formatZettelDate,
-    formatZettelDateAsDay,
+    formatDay,
     parseZettelDate,
     parseZettelDay,
     DateMayTime,
+    mkDateMayTime,
+    getDay
   )
 where
 
+import Data.Aeson (FromJSON, ToJSON)
 import Data.TagTree (Tag)
 import Data.Time
 import Data.YAML
 import Relude
 
-type DateMayTime = Either Day LocalTime
-
 -- | YAML metadata in a zettel markdown file
 data Meta = Meta
   { title :: Maybe Text,
@@ -43,7 +45,7 @@ instance FromYAML Meta where
       Meta
         <$> m .:? "title"
         -- "keywords" is an alias for "tags"
-        <*> (liftA2 (<|>) (m .:? "tags") (m .:? "keywords"))
+        <*> liftA2 (<|>) (m .:? "tags") (m .:? "keywords")
         <*> m .:? "date"
         <*> m .:? "unlisted"
 
@@ -57,6 +59,21 @@ instance FromYAML Meta where
 --         "date" .= date
 --       ]
 
+-- | Like `Day` but with optional time.
+newtype DateMayTime = DateMayTime {unDateMayTime :: (Day, Maybe TimeOfDay)}
+  deriving (Eq, Show, Generic, Ord, ToJSON, FromJSON)
+
+mkDateMayTime :: Either Day LocalTime -> DateMayTime
+mkDateMayTime =
+  DateMayTime . \case
+    Left day ->
+      (day, Nothing)
+    Right datetime ->
+      localDay &&& Just . localTimeOfDay $ datetime
+
+getDay :: DateMayTime -> Day
+getDay = fst . unDateMayTime
+
 instance FromYAML DateMayTime where
   parseYAML =
     parseZettelDate <=< parseYAML @Text
@@ -66,20 +83,22 @@ instance ToYAML DateMayTime where
     toYAML . formatZettelDate
 
 formatZettelDate :: DateMayTime -> Text
-formatZettelDate =
-  toText . \case
-    Left day -> formatTime defaultTimeLocale dateFormat day
-    Right localtime -> formatTime defaultTimeLocale dateTimeFormat localtime
+formatZettelDate (DateMayTime (day, mtime)) =
+  maybe (formatDay day) (formatTime' dateTimeFormat) mtime
+  where
+
+formatDay :: Day -> Text
+formatDay = formatTime' dateFormat
 
-formatZettelDateAsDay :: DateMayTime -> Text
-formatZettelDateAsDay =
-  toText . formatTime defaultTimeLocale dateFormat . \case
-    Left day -> day
-    Right localtime -> localDay localtime
+-- | Like `formatTime` but with default time locale and returning Text
+formatTime' :: FormatTime t => String -> t -> Text
+formatTime' s = toText . formatTime defaultTimeLocale s
 
 parseZettelDate :: (MonadFail m, Alternative m) => Text -> m DateMayTime
-parseZettelDate (toString -> s) =
-  Left <$> parseTimeM False defaultTimeLocale dateFormat s <|> Right <$> parseTimeM False defaultTimeLocale dateTimeFormat s
+parseZettelDate (toString -> s) = do
+  fmap mkDateMayTime $
+    fmap Left (parseTimeM False defaultTimeLocale dateFormat s)
+      <|> fmap Right (parseTimeM False defaultTimeLocale dateTimeFormat s)
 
 parseZettelDay :: MonadFail m => Text -> m Day
 parseZettelDay =
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs
index 2f3b144a5..7da595b71 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs
@@ -40,7 +40,7 @@ parseZettel format zreader fn zid s = do
           date = case zid of
             -- We ignore the "data" meta field on legacy Date IDs, which encode the
             -- creation date in the ID.
-            ZettelDateID v _ -> Just $ Left v
+            ZettelDateID v _ -> Just $ Meta.mkDateMayTime $ Left v
             ZettelCustomID _ -> Meta.date =<< meta
           unlisted = fromMaybe False $ Meta.unlisted =<< meta
           (queries, errors) = runWriter $ extractQueries doc
diff --git a/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs b/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
index 87dbc5a19..6ce2a7a11 100644
--- a/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
+++ b/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
@@ -8,14 +8,13 @@ module Neuron.Zettelkasten.ZettelSpec
 where
 
 import Data.TagTree
-import Data.Time (LocalTime (LocalTime))
 import Data.Time.Calendar
-import Data.Time.LocalTime (TimeOfDay (TimeOfDay))
+import Data.Time.LocalTime
 import Neuron.Reader.Markdown
 import Neuron.Reader.Type
 import Neuron.Zettelkasten.ID
 import Neuron.Zettelkasten.Zettel
-import Neuron.Zettelkasten.Zettel.Meta (Meta)
+import Neuron.Zettelkasten.Zettel.Meta
 import Relude
 import Test.Hspec
 
@@ -26,36 +25,48 @@ spec = do
       noContent = MetadataOnly ()
   describe "sortZettelsReverseChronological" $ do
     let mkDay = fromGregorian 2020 3
-        mkZettelDay = Just . Left . mkDay
-        mkZettelLocalTime day hh mm = Just $ Right $ LocalTime (mkDay day) $ TimeOfDay hh mm 0
+        mkZettelDay n =
+          Just $ mkDateMayTime $ Left (mkDay n)
+        mkZettelLocalTime day hh mm =
+          Just $ mkDateMayTime $ Right $ LocalTime (mkDay day) (TimeOfDay hh mm 0)
 
         (_ :: Maybe Meta, _dummyContent) = either (error . show) id $ parseMarkdown "<spec>" "Dummy"
 
-        mkZettel day date idx =
+        mkZettel zid datetime =
           Zettel
-            (ZettelDateID (mkDay day) idx)
+            (ZettelCustomID zid)
             ZettelFormat_Markdown
             "<spec>.md"
             "Some title"
             False
             [Tag "science", Tag "journal/class"]
-            date
+            datetime
             False
             noQueries
             noError
             noContent
 
     it "sorts correctly with day" $ do
-      let zs = [mkZettel 3 (mkZettelDay 3) 2, mkZettel 5 (mkZettelDay 5) 1]
+      let zs =
+            [ mkZettel "a" (mkZettelDay 3),
+              mkZettel "b" (mkZettelDay 5)
+            ]
       sortZettelsReverseChronological zs
         `shouldBe` reverse zs
 
     it "sorts correctly with localtime" $ do
-      let zs = [mkZettel 3 (mkZettelLocalTime 3 9 59) 2, mkZettel 3 (mkZettelLocalTime 3 10 0) 1]
+      let zs =
+            [ mkZettel "a" (mkZettelLocalTime 3 9 59),
+              mkZettel "b" (mkZettelLocalTime 3 10 0)
+            ]
       sortZettelsReverseChronological zs
         `shouldBe` reverse zs
 
     it "sorts correctly with mixed dates" $ do
-      let zs = [mkZettel 3 (mkZettelDay 5) 2, mkZettel 3 (mkZettelLocalTime 3 0 0) 1]
+      let zs =
+            [ mkZettel "c" (mkZettelLocalTime 7 0 0),
+              mkZettel "a" (mkZettelDay 5),
+              mkZettel "b" (mkZettelLocalTime 3 0 0)
+            ]
       sortZettelsReverseChronological zs
-        `shouldBe` reverse zs
+        `shouldBe` zs

From e3dc0eef3e9e44040695e622dfcdb01dc55865d8 Mon Sep 17 00:00:00 2001
From: Sridhar Ratnakumar <srid@srid.ca>
Date: Tue, 18 Aug 2020 17:46:34 -0400
Subject: [PATCH 12/16] Revert changes to org module

---
 neuron/src/app/Neuron/Reader/Org.hs  |  6 ++----
 neuron/test/Neuron/Reader/OrgSpec.hs | 26 --------------------------
 2 files changed, 2 insertions(+), 30 deletions(-)
 delete mode 100644 neuron/test/Neuron/Reader/OrgSpec.hs

diff --git a/neuron/src/app/Neuron/Reader/Org.hs b/neuron/src/app/Neuron/Reader/Org.hs
index 40a3526cd..02785f3aa 100644
--- a/neuron/src/app/Neuron/Reader/Org.hs
+++ b/neuron/src/app/Neuron/Reader/Org.hs
@@ -9,7 +9,6 @@
 
 module Neuron.Reader.Org
   ( parseOrg,
-    parseDate,
   )
 where
 
@@ -44,8 +43,7 @@ extractMetadata doc
     pure $ Just Meta {..}
   | otherwise = pure Nothing
   where
+    parseDate :: Text -> Either ZettelParseError DateMayTime
+    parseDate date = maybeToRight (Tagged $ "Invalid date format: " <> date) $ parseZettelDate @Maybe date
     parseUnlisted :: Text -> Bool
     parseUnlisted a = toLower a == "true"
-
-parseDate :: Text -> Either ZettelParseError DateMayTime
-parseDate date = maybeToRight (Tagged $ "Invalid date format: " <> date) $ parseZettelDate @Maybe date
diff --git a/neuron/test/Neuron/Reader/OrgSpec.hs b/neuron/test/Neuron/Reader/OrgSpec.hs
deleted file mode 100644
index 87ee95c86..000000000
--- a/neuron/test/Neuron/Reader/OrgSpec.hs
+++ /dev/null
@@ -1,26 +0,0 @@
-{-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE RecordWildCards #-}
-{-# LANGUAGE NoImplicitPrelude #-}
-
-module Neuron.Reader.OrgSpec
-  ( spec,
-  )
-where
-
-import Data.Tagged (Tagged (Tagged))
-import Data.Time (LocalTime (LocalTime))
-import Data.Time.Calendar
-import Data.Time.LocalTime (TimeOfDay (TimeOfDay))
-import Neuron.Reader.Org
-import Relude
-import Test.Hspec
-
-spec :: Spec
-spec = do
-  describe "date-tag parsing" $ do
-    it "with day" $ do
-      parseDate "2020-08-16" `shouldBe` Right (Left (ModifiedJulianDay 59077))
-    it "with localtime" $ do
-      parseDate "2020-08-16T09:42" `shouldBe` Right (Right (LocalTime (ModifiedJulianDay 59077) (TimeOfDay 9 42 0)))
-    it "with invalid" $ do
-      parseDate "2020-08-16 09:42" `shouldBe` Left (Tagged $ "Invalid date format: " <> "2020-08-16 09:42")

From c6449e73e0047c61da6acfe3103c816cb24d1aff Mon Sep 17 00:00:00 2001
From: Sridhar Ratnakumar <srid@srid.ca>
Date: Tue, 18 Aug 2020 17:46:46 -0400
Subject: [PATCH 13/16] Run ormolu, etc.

---
 .../lib/Neuron/Zettelkasten/Query/Parser.hs   |  4 +--
 .../lib/Neuron/Zettelkasten/Zettel/Meta.hs    | 32 ++++++++-----------
 2 files changed, 15 insertions(+), 21 deletions(-)

diff --git a/neuron/src/lib/Neuron/Zettelkasten/Query/Parser.hs b/neuron/src/lib/Neuron/Zettelkasten/Query/Parser.hs
index da677fe5d..f6b88a48f 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Query/Parser.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Query/Parser.hs
@@ -7,11 +7,11 @@
 {-# LANGUAGE QuasiQuotes #-}
 {-# LANGUAGE RecordWildCards #-}
 {-# LANGUAGE ScopedTypeVariables #-}
-{-# LANGUAGE TypeApplications #-}
 {-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE TypeApplications #-}
 {-# LANGUAGE TypeFamilies #-}
-{-# LANGUAGE NoImplicitPrelude #-}
 {-# LANGUAGE ViewPatterns #-}
+{-# LANGUAGE NoImplicitPrelude #-}
 
 module Neuron.Zettelkasten.Query.Parser
   ( queryFromURI,
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
index 3a4d7269b..501710e51 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
@@ -15,10 +15,9 @@ module Neuron.Zettelkasten.Zettel.Meta
     formatZettelDate,
     formatDay,
     parseZettelDate,
-    parseZettelDay,
     DateMayTime,
     mkDateMayTime,
-    getDay
+    getDay,
   )
 where
 
@@ -63,6 +62,14 @@ instance FromYAML Meta where
 newtype DateMayTime = DateMayTime {unDateMayTime :: (Day, Maybe TimeOfDay)}
   deriving (Eq, Show, Generic, Ord, ToJSON, FromJSON)
 
+instance FromYAML DateMayTime where
+  parseYAML =
+    parseZettelDate <=< parseYAML @Text
+
+instance ToYAML DateMayTime where
+  toYAML =
+    toYAML . formatZettelDate
+
 mkDateMayTime :: Either Day LocalTime -> DateMayTime
 mkDateMayTime =
   DateMayTime . \case
@@ -74,38 +81,25 @@ mkDateMayTime =
 getDay :: DateMayTime -> Day
 getDay = fst . unDateMayTime
 
-instance FromYAML DateMayTime where
-  parseYAML =
-    parseZettelDate <=< parseYAML @Text
-
-instance ToYAML DateMayTime where
-  toYAML =
-    toYAML . formatZettelDate
-
 formatZettelDate :: DateMayTime -> Text
 formatZettelDate (DateMayTime (day, mtime)) =
   maybe (formatDay day) (formatTime' dateTimeFormat) mtime
-  where
 
 formatDay :: Day -> Text
 formatDay = formatTime' dateFormat
 
--- | Like `formatTime` but with default time locale and returning Text
-formatTime' :: FormatTime t => String -> t -> Text
-formatTime' s = toText . formatTime defaultTimeLocale s
-
 parseZettelDate :: (MonadFail m, Alternative m) => Text -> m DateMayTime
 parseZettelDate (toString -> s) = do
   fmap mkDateMayTime $
     fmap Left (parseTimeM False defaultTimeLocale dateFormat s)
       <|> fmap Right (parseTimeM False defaultTimeLocale dateTimeFormat s)
 
-parseZettelDay :: MonadFail m => Text -> m Day
-parseZettelDay =
-  parseTimeM False defaultTimeLocale dateFormat . toString
-
 dateFormat :: String
 dateFormat = "%Y-%m-%d"
 
 dateTimeFormat :: String
 dateTimeFormat = "%Y-%m-%dT%H:%M"
+
+-- | Like `formatTime` but with default time locale and returning Text
+formatTime' :: FormatTime t => String -> t -> Text
+formatTime' s = toText . formatTime defaultTimeLocale s

From fc172c14aadf54e1e8deda8aac63df2686b592ba Mon Sep 17 00:00:00 2001
From: Sridhar Ratnakumar <srid@srid.ca>
Date: Tue, 18 Aug 2020 17:58:46 -0400
Subject: [PATCH 14/16] Restore `elTime` to accept time type, not string

---
 neuron/src/lib/Neuron/Web/Query/View.hs           |  3 +--
 neuron/src/lib/Neuron/Web/Widget.hs               |  7 +++++--
 neuron/src/lib/Neuron/Web/Zettel/View.hs          |  5 ++---
 neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs | 12 +++++++++++-
 4 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/neuron/src/lib/Neuron/Web/Query/View.hs b/neuron/src/lib/Neuron/Web/Query/View.hs
index 3bdf69be9..3fea82f3a 100644
--- a/neuron/src/lib/Neuron/Web/Query/View.hs
+++ b/neuron/src/lib/Neuron/Web/Query/View.hs
@@ -32,7 +32,6 @@ import Neuron.Zettelkasten.Connection
 import Neuron.Zettelkasten.ID
 import Neuron.Zettelkasten.Query.Theme (LinkView (..), ZettelsView (..))
 import Neuron.Zettelkasten.Zettel
-import Neuron.Zettelkasten.Zettel.Meta (formatDay, getDay)
 import Reflex.Dom.Core hiding (count, tag)
 import Relude
 
@@ -103,7 +102,7 @@ renderZettelLink conn (fromMaybe def -> linkView) Zettel {..} = do
           LinkView_Default ->
             Nothing
           LinkView_ShowDate ->
-            elTime . formatDay . getDay <$> zettelDate
+            elTime <$> zettelDate
           LinkView_ShowID ->
             Just $ el "tt" $ text $ zettelIDText zettelID
       classes :: [Text] = catMaybes $ [Just "zettel-link-container"] <> [connClass, rawClass]
diff --git a/neuron/src/lib/Neuron/Web/Widget.hs b/neuron/src/lib/Neuron/Web/Widget.hs
index 1756cd10d..4b930495b 100644
--- a/neuron/src/lib/Neuron/Web/Widget.hs
+++ b/neuron/src/lib/Neuron/Web/Widget.hs
@@ -1,18 +1,21 @@
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE ViewPatterns #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE NoImplicitPrelude #-}
 
 module Neuron.Web.Widget where
 
 import qualified Data.Text as T
+import Neuron.Zettelkasten.Zettel.Meta (DateMayTime, formatDateMayTime, formatDay, getDay)
 import Reflex.Dom.Core
 import Relude
 
 -- | <time> element
-elTime :: DomBuilder t m => Text -> m ()
+elTime :: DomBuilder t m => DateMayTime -> m ()
 elTime t = do
   -- cf. https://developer.mozilla.org/en-US/docs/Web/HTML/Element/time#Attributes
-  elAttr "time" ("datetime" =: t) $ text t
+  elAttr "time" ("datetime" =: formatDateMayTime t) $ do
+    text $ formatDay $ getDay t
 
 semanticIcon :: DomBuilder t m => Text -> m ()
 semanticIcon name = elClass "i" (name <> " icon") blank
diff --git a/neuron/src/lib/Neuron/Web/Zettel/View.hs b/neuron/src/lib/Neuron/Web/Zettel/View.hs
index 83b58e808..4ab4ac189 100644
--- a/neuron/src/lib/Neuron/Web/Zettel/View.hs
+++ b/neuron/src/lib/Neuron/Web/Zettel/View.hs
@@ -28,7 +28,6 @@ import qualified Neuron.Zettelkasten.Graph as G
 import Neuron.Zettelkasten.Query.Error (QueryError, showQueryError)
 import qualified Neuron.Zettelkasten.Query.Eval as Q
 import Neuron.Zettelkasten.Zettel
-import Neuron.Zettelkasten.Zettel.Meta (formatZettelDate)
 import Reflex.Dom.Core hiding ((&))
 import Reflex.Dom.Pandoc
 import Relude hiding ((&))
@@ -120,10 +119,10 @@ renderZettelContent handleLink Zettel {..} = do
     unless zettelTitleInBody $ do
       el "h1" $ text zettelTitle
     void $ elPandoc (Config handleLink) zettelContent
-    whenJust zettelDate $ \day ->
+    whenJust zettelDate $ \date ->
       divClass "metadata" $ do
         elAttr "div" ("class" =: "date" <> "title" =: "Zettel date") $ do
-          elTime $ formatZettelDate day
+          elTime date
 
 renderZettelRawContent :: (DomBuilder t m) => ZettelT Text -> m ()
 renderZettelRawContent Zettel {..} = do
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
index 501710e51..f891b49b8 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
@@ -3,6 +3,7 @@
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE TupleSections #-}
 {-# LANGUAGE RecordWildCards #-}
 {-# LANGUAGE TypeApplications #-}
 {-# LANGUAGE ViewPatterns #-}
@@ -14,6 +15,8 @@ module Neuron.Zettelkasten.Zettel.Meta
     dateTimeFormat,
     formatZettelDate,
     formatDay,
+    formatLocalTime,
+    formatDateMayTime,
     parseZettelDate,
     DateMayTime,
     mkDateMayTime,
@@ -81,13 +84,20 @@ mkDateMayTime =
 getDay :: DateMayTime -> Day
 getDay = fst . unDateMayTime
 
+formatDateMayTime :: DateMayTime -> Text
+formatDateMayTime (DateMayTime (day, mtime)) =
+  maybe (formatDay day) (formatLocalTime . LocalTime day) mtime
+
 formatZettelDate :: DateMayTime -> Text
 formatZettelDate (DateMayTime (day, mtime)) =
-  maybe (formatDay day) (formatTime' dateTimeFormat) mtime
+  maybe (formatDay day) (formatLocalTime . LocalTime day) mtime
 
 formatDay :: Day -> Text
 formatDay = formatTime' dateFormat
 
+formatLocalTime :: LocalTime -> Text
+formatLocalTime = formatTime' dateTimeFormat
+
 parseZettelDate :: (MonadFail m, Alternative m) => Text -> m DateMayTime
 parseZettelDate (toString -> s) = do
   fmap mkDateMayTime $

From 8cb90b1489a0f6c87e8e7aad94b00afcaa196b28 Mon Sep 17 00:00:00 2001
From: Sridhar Ratnakumar <srid@srid.ca>
Date: Tue, 18 Aug 2020 18:04:53 -0400
Subject: [PATCH 15/16] Simplify naming

---
 neuron/src/app/Neuron/CLI/New.hs              |  5 ++--
 neuron/src/app/Neuron/CLI/Types.hs            |  8 +++----
 neuron/src/app/Neuron/Reader/Org.hs           |  4 ++--
 .../lib/Neuron/Zettelkasten/Zettel/Meta.hs    | 24 +++++++++----------
 4 files changed, 19 insertions(+), 22 deletions(-)

diff --git a/neuron/src/app/Neuron/CLI/New.hs b/neuron/src/app/Neuron/CLI/New.hs
index 06e6d5a70..5c6b568be 100644
--- a/neuron/src/app/Neuron/CLI/New.hs
+++ b/neuron/src/app/Neuron/CLI/New.hs
@@ -23,7 +23,7 @@ import Neuron.Web.Generate as Gen
 import Neuron.Zettelkasten.ID (zettelIDSourceFileName)
 import qualified Neuron.Zettelkasten.ID.Scheme as IDScheme
 import Neuron.Zettelkasten.Zettel (zettelID)
-import Neuron.Zettelkasten.Zettel.Meta
+import Neuron.Zettelkasten.Zettel.Meta (DateMayTime, formatDateMayTime)
 import Options.Applicative
 import Relude
 import Rib.Shake (ribInputDir)
@@ -83,7 +83,7 @@ newZettelFile NewCommand {..} config = do
 
 -- TODO use configurable template files?
 defaultZettelContent :: ZettelFormat -> DateMayTime -> Maybe Text -> Text
-defaultZettelContent format dmt mtitle = case format of
+defaultZettelContent format (formatDateMayTime -> date) mtitle = case format of
   ZettelFormat_Markdown ->
     T.intercalate
       "\n"
@@ -104,6 +104,5 @@ defaultZettelContent format dmt mtitle = case format of
         "\n"
       ]
   where
-    date = formatZettelDate dmt
     defaultTitleName = "Zettel created on " <> date
     title = maybe defaultTitleName T.strip mtitle
diff --git a/neuron/src/app/Neuron/CLI/Types.hs b/neuron/src/app/Neuron/CLI/Types.hs
index e6b8e77ab..20ac2376d 100644
--- a/neuron/src/app/Neuron/CLI/Types.hs
+++ b/neuron/src/app/Neuron/CLI/Types.hs
@@ -34,10 +34,10 @@ import qualified Neuron.Zettelkasten.Query.Parser as Q
 import Neuron.Zettelkasten.Zettel as Q
 import Neuron.Zettelkasten.Zettel.Meta
   ( DateMayTime,
-    formatZettelDate,
+    formatDateMayTime,
     getDay,
     mkDateMayTime,
-    parseZettelDate,
+    parseDateMayTime,
   )
 import Options.Applicative
 import Relude
@@ -138,7 +138,7 @@ commandParser defaultNotesDir now = do
           long "date"
             <> metavar "DATE/TIME"
             <> value (mkDateMayTime $ Right now)
-            <> showDefaultWith (toString . formatZettelDate)
+            <> showDefaultWith (toString . formatDateMayTime)
             <> help "Zettel creation date/time"
       -- NOTE: optparse-applicative picks the first option as the default.
       idSchemeF <-
@@ -234,4 +234,4 @@ commandParser defaultNotesDir now = do
           Left $ displayException e
     dateReader :: ReadM DateMayTime
     dateReader =
-      maybeReader (parseZettelDate . toText)
+      maybeReader (parseDateMayTime . toText)
diff --git a/neuron/src/app/Neuron/Reader/Org.hs b/neuron/src/app/Neuron/Reader/Org.hs
index 02785f3aa..2443b72d9 100644
--- a/neuron/src/app/Neuron/Reader/Org.hs
+++ b/neuron/src/app/Neuron/Reader/Org.hs
@@ -17,7 +17,7 @@ import Data.TagTree (Tag (Tag))
 import Data.Tagged
 import Data.Text (toLower)
 import Neuron.Reader.Type (ZettelParseError, ZettelReader)
-import Neuron.Zettelkasten.Zettel.Meta (DateMayTime, Meta (..), parseZettelDate)
+import Neuron.Zettelkasten.Zettel.Meta (DateMayTime, Meta (..), parseDateMayTime)
 import Relude
 import Relude.Extra.Map (lookup)
 import Text.Pandoc (def, runPure)
@@ -44,6 +44,6 @@ extractMetadata doc
   | otherwise = pure Nothing
   where
     parseDate :: Text -> Either ZettelParseError DateMayTime
-    parseDate date = maybeToRight (Tagged $ "Invalid date format: " <> date) $ parseZettelDate @Maybe date
+    parseDate date = maybeToRight (Tagged $ "Invalid date format: " <> date) $ parseDateMayTime @Maybe date
     parseUnlisted :: Text -> Bool
     parseUnlisted a = toLower a == "true"
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
index f891b49b8..4d150c3b6 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
@@ -12,15 +12,17 @@
 
 module Neuron.Zettelkasten.Zettel.Meta
   ( Meta (..),
+    -- Date type
+    DateMayTime,
+    mkDateMayTime,
+    getDay,
+    -- Date formatting
     dateTimeFormat,
-    formatZettelDate,
     formatDay,
     formatLocalTime,
     formatDateMayTime,
-    parseZettelDate,
-    DateMayTime,
-    mkDateMayTime,
-    getDay,
+    -- Date parsing
+    parseDateMayTime
   )
 where
 
@@ -67,11 +69,11 @@ newtype DateMayTime = DateMayTime {unDateMayTime :: (Day, Maybe TimeOfDay)}
 
 instance FromYAML DateMayTime where
   parseYAML =
-    parseZettelDate <=< parseYAML @Text
+    parseDateMayTime <=< parseYAML @Text
 
 instance ToYAML DateMayTime where
   toYAML =
-    toYAML . formatZettelDate
+    toYAML . formatDateMayTime
 
 mkDateMayTime :: Either Day LocalTime -> DateMayTime
 mkDateMayTime =
@@ -88,18 +90,14 @@ formatDateMayTime :: DateMayTime -> Text
 formatDateMayTime (DateMayTime (day, mtime)) =
   maybe (formatDay day) (formatLocalTime . LocalTime day) mtime
 
-formatZettelDate :: DateMayTime -> Text
-formatZettelDate (DateMayTime (day, mtime)) =
-  maybe (formatDay day) (formatLocalTime . LocalTime day) mtime
-
 formatDay :: Day -> Text
 formatDay = formatTime' dateFormat
 
 formatLocalTime :: LocalTime -> Text
 formatLocalTime = formatTime' dateTimeFormat
 
-parseZettelDate :: (MonadFail m, Alternative m) => Text -> m DateMayTime
-parseZettelDate (toString -> s) = do
+parseDateMayTime :: (MonadFail m, Alternative m) => Text -> m DateMayTime
+parseDateMayTime (toString -> s) = do
   fmap mkDateMayTime $
     fmap Left (parseTimeM False defaultTimeLocale dateFormat s)
       <|> fmap Right (parseTimeM False defaultTimeLocale dateTimeFormat s)

From 98162b0917c2831450703b186ee08265128b9732 Mon Sep 17 00:00:00 2001
From: Sridhar Ratnakumar <srid@srid.ca>
Date: Tue, 18 Aug 2020 18:09:45 -0400
Subject: [PATCH 16/16] Separate out datemaytime type

It is nothing to do with Meta.hs
---
 neuron/neuron.cabal                           |  1 +
 neuron/src/app/Neuron/CLI/New.hs              |  2 +-
 neuron/src/app/Neuron/CLI/Types.hs            | 14 ++--
 neuron/src/app/Neuron/Reader/Org.hs           |  3 +-
 neuron/src/lib/Data/Time/DateMayTime.hs       | 80 +++++++++++++++++++
 neuron/src/lib/Neuron/Web/Widget.hs           |  2 +-
 neuron/src/lib/Neuron/Zettelkasten/Zettel.hs  |  2 +-
 .../lib/Neuron/Zettelkasten/Zettel/Meta.hs    | 63 +--------------
 .../lib/Neuron/Zettelkasten/Zettel/Parser.hs  |  3 +-
 neuron/test/Neuron/Zettelkasten/ZettelSpec.hs |  1 +
 10 files changed, 97 insertions(+), 74 deletions(-)
 create mode 100644 neuron/src/lib/Data/Time/DateMayTime.hs

diff --git a/neuron/neuron.cabal b/neuron/neuron.cabal
index 1d93ebcec..2fc96c480 100644
--- a/neuron/neuron.cabal
+++ b/neuron/neuron.cabal
@@ -107,6 +107,7 @@ library
     Data.Graph.Labelled.Type
     Data.Graph.Labelled.Algorithm
     Data.Graph.Labelled.Build
+    Data.Time.DateMayTime
 
 -- A trick to make ghcid reload if library dependencies change
 -- https://haskell.zettel.page/2012605.html
diff --git a/neuron/src/app/Neuron/CLI/New.hs b/neuron/src/app/Neuron/CLI/New.hs
index 5c6b568be..f0403a9a6 100644
--- a/neuron/src/app/Neuron/CLI/New.hs
+++ b/neuron/src/app/Neuron/CLI/New.hs
@@ -15,6 +15,7 @@ import qualified Data.Set as Set
 import Data.Some
 import Data.Text (strip)
 import qualified Data.Text as T
+import Data.Time.DateMayTime (DateMayTime, formatDateMayTime)
 import Development.Shake (Action)
 import Neuron.CLI.Types
 import Neuron.Config.Type (Config (..), getZettelFormats)
@@ -23,7 +24,6 @@ import Neuron.Web.Generate as Gen
 import Neuron.Zettelkasten.ID (zettelIDSourceFileName)
 import qualified Neuron.Zettelkasten.ID.Scheme as IDScheme
 import Neuron.Zettelkasten.Zettel (zettelID)
-import Neuron.Zettelkasten.Zettel.Meta (DateMayTime, formatDateMayTime)
 import Options.Applicative
 import Relude
 import Rib.Shake (ribInputDir)
diff --git a/neuron/src/app/Neuron/CLI/Types.hs b/neuron/src/app/Neuron/CLI/Types.hs
index 20ac2376d..e694753c2 100644
--- a/neuron/src/app/Neuron/CLI/Types.hs
+++ b/neuron/src/app/Neuron/CLI/Types.hs
@@ -23,6 +23,13 @@ import Data.Default (def)
 import Data.Some
 import Data.TagTree (mkTagPattern)
 import Data.Time
+import Data.Time.DateMayTime
+  ( DateMayTime,
+    formatDateMayTime,
+    getDay,
+    mkDateMayTime,
+    parseDateMayTime,
+  )
 import Neuron.Reader.Type (ZettelFormat)
 import qualified Neuron.Web.Route as R
 import qualified Neuron.Zettelkasten.Connection as C
@@ -32,13 +39,6 @@ import qualified Neuron.Zettelkasten.Query.Error as Q
 import Neuron.Zettelkasten.Query.Graph as Q
 import qualified Neuron.Zettelkasten.Query.Parser as Q
 import Neuron.Zettelkasten.Zettel as Q
-import Neuron.Zettelkasten.Zettel.Meta
-  ( DateMayTime,
-    formatDateMayTime,
-    getDay,
-    mkDateMayTime,
-    parseDateMayTime,
-  )
 import Options.Applicative
 import Relude
 import qualified Rib.Cli
diff --git a/neuron/src/app/Neuron/Reader/Org.hs b/neuron/src/app/Neuron/Reader/Org.hs
index 2443b72d9..24e495ac5 100644
--- a/neuron/src/app/Neuron/Reader/Org.hs
+++ b/neuron/src/app/Neuron/Reader/Org.hs
@@ -16,8 +16,9 @@ import qualified Data.Map as Map
 import Data.TagTree (Tag (Tag))
 import Data.Tagged
 import Data.Text (toLower)
+import Data.Time.DateMayTime (DateMayTime, parseDateMayTime)
 import Neuron.Reader.Type (ZettelParseError, ZettelReader)
-import Neuron.Zettelkasten.Zettel.Meta (DateMayTime, Meta (..), parseDateMayTime)
+import Neuron.Zettelkasten.Zettel.Meta (Meta (..))
 import Relude
 import Relude.Extra.Map (lookup)
 import Text.Pandoc (def, runPure)
diff --git a/neuron/src/lib/Data/Time/DateMayTime.hs b/neuron/src/lib/Data/Time/DateMayTime.hs
new file mode 100644
index 000000000..a4d803665
--- /dev/null
+++ b/neuron/src/lib/Data/Time/DateMayTime.hs
@@ -0,0 +1,80 @@
+{-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE TupleSections #-}
+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE TypeApplications #-}
+{-# LANGUAGE ViewPatterns #-}
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# OPTIONS_GHC -fno-warn-orphans #-}
+
+module Data.Time.DateMayTime
+  ( -- Date type
+    DateMayTime,
+    mkDateMayTime,
+    getDay,
+    -- Date formatting
+    dateTimeFormat,
+    formatDay,
+    formatLocalTime,
+    formatDateMayTime,
+    -- Date parsing
+    parseDateMayTime
+  )
+where
+
+import Data.Aeson (FromJSON, ToJSON)
+import Data.Time
+import Data.YAML
+import Relude
+
+-- | Like `Day` but with optional time.
+newtype DateMayTime = DateMayTime {unDateMayTime :: (Day, Maybe TimeOfDay)}
+  deriving (Eq, Show, Generic, Ord, ToJSON, FromJSON)
+
+instance FromYAML DateMayTime where
+  parseYAML =
+    parseDateMayTime <=< parseYAML @Text
+
+instance ToYAML DateMayTime where
+  toYAML =
+    toYAML . formatDateMayTime
+
+mkDateMayTime :: Either Day LocalTime -> DateMayTime
+mkDateMayTime =
+  DateMayTime . \case
+    Left day ->
+      (day, Nothing)
+    Right datetime ->
+      localDay &&& Just . localTimeOfDay $ datetime
+
+getDay :: DateMayTime -> Day
+getDay = fst . unDateMayTime
+
+formatDateMayTime :: DateMayTime -> Text
+formatDateMayTime (DateMayTime (day, mtime)) =
+  maybe (formatDay day) (formatLocalTime . LocalTime day) mtime
+
+formatDay :: Day -> Text
+formatDay = formatTime' dateFormat
+
+formatLocalTime :: LocalTime -> Text
+formatLocalTime = formatTime' dateTimeFormat
+
+parseDateMayTime :: (MonadFail m, Alternative m) => Text -> m DateMayTime
+parseDateMayTime (toString -> s) = do
+  fmap mkDateMayTime $
+    fmap Left (parseTimeM False defaultTimeLocale dateFormat s)
+      <|> fmap Right (parseTimeM False defaultTimeLocale dateTimeFormat s)
+
+dateFormat :: String
+dateFormat = "%Y-%m-%d"
+
+dateTimeFormat :: String
+dateTimeFormat = "%Y-%m-%dT%H:%M"
+
+-- | Like `formatTime` but with default time locale and returning Text
+formatTime' :: FormatTime t => String -> t -> Text
+formatTime' s = toText . formatTime defaultTimeLocale s
diff --git a/neuron/src/lib/Neuron/Web/Widget.hs b/neuron/src/lib/Neuron/Web/Widget.hs
index 4b930495b..c17f82c3e 100644
--- a/neuron/src/lib/Neuron/Web/Widget.hs
+++ b/neuron/src/lib/Neuron/Web/Widget.hs
@@ -6,7 +6,7 @@
 module Neuron.Web.Widget where
 
 import qualified Data.Text as T
-import Neuron.Zettelkasten.Zettel.Meta (DateMayTime, formatDateMayTime, formatDay, getDay)
+import Data.Time.DateMayTime (DateMayTime, formatDateMayTime, formatDay, getDay)
 import Reflex.Dom.Core
 import Relude
 
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel.hs
index eed5b4384..4cf957e3c 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel.hs
@@ -26,12 +26,12 @@ import Data.GADT.Show.TH
 import Data.Graph.Labelled (Vertex (..))
 import Data.Some
 import Data.TagTree (Tag, TagPattern (..))
+import Data.Time.DateMayTime (DateMayTime)
 import Neuron.Reader.Type
 import Neuron.Zettelkasten.Connection
 import Neuron.Zettelkasten.ID
 import Neuron.Zettelkasten.Query.Error
 import Neuron.Zettelkasten.Query.Theme
-import Neuron.Zettelkasten.Zettel.Meta (DateMayTime)
 import Relude hiding (show)
 import Text.Pandoc.Definition (Pandoc (..))
 import Text.Show (Show (show))
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
index 4d150c3b6..8b3ab0619 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Meta.hs
@@ -12,24 +12,12 @@
 
 module Neuron.Zettelkasten.Zettel.Meta
   ( Meta (..),
-    -- Date type
-    DateMayTime,
-    mkDateMayTime,
-    getDay,
-    -- Date formatting
-    dateTimeFormat,
-    formatDay,
-    formatLocalTime,
-    formatDateMayTime,
-    -- Date parsing
-    parseDateMayTime
   )
 where
 
-import Data.Aeson (FromJSON, ToJSON)
 import Data.TagTree (Tag)
-import Data.Time
 import Data.YAML
+import Data.Time.DateMayTime (DateMayTime)
 import Relude
 
 -- | YAML metadata in a zettel markdown file
@@ -62,52 +50,3 @@ instance FromYAML Meta where
 --         "tags" .= tags,
 --         "date" .= date
 --       ]
-
--- | Like `Day` but with optional time.
-newtype DateMayTime = DateMayTime {unDateMayTime :: (Day, Maybe TimeOfDay)}
-  deriving (Eq, Show, Generic, Ord, ToJSON, FromJSON)
-
-instance FromYAML DateMayTime where
-  parseYAML =
-    parseDateMayTime <=< parseYAML @Text
-
-instance ToYAML DateMayTime where
-  toYAML =
-    toYAML . formatDateMayTime
-
-mkDateMayTime :: Either Day LocalTime -> DateMayTime
-mkDateMayTime =
-  DateMayTime . \case
-    Left day ->
-      (day, Nothing)
-    Right datetime ->
-      localDay &&& Just . localTimeOfDay $ datetime
-
-getDay :: DateMayTime -> Day
-getDay = fst . unDateMayTime
-
-formatDateMayTime :: DateMayTime -> Text
-formatDateMayTime (DateMayTime (day, mtime)) =
-  maybe (formatDay day) (formatLocalTime . LocalTime day) mtime
-
-formatDay :: Day -> Text
-formatDay = formatTime' dateFormat
-
-formatLocalTime :: LocalTime -> Text
-formatLocalTime = formatTime' dateTimeFormat
-
-parseDateMayTime :: (MonadFail m, Alternative m) => Text -> m DateMayTime
-parseDateMayTime (toString -> s) = do
-  fmap mkDateMayTime $
-    fmap Left (parseTimeM False defaultTimeLocale dateFormat s)
-      <|> fmap Right (parseTimeM False defaultTimeLocale dateTimeFormat s)
-
-dateFormat :: String
-dateFormat = "%Y-%m-%d"
-
-dateTimeFormat :: String
-dateTimeFormat = "%Y-%m-%dT%H:%M"
-
--- | Like `formatTime` but with default time locale and returning Text
-formatTime' :: FormatTime t => String -> t -> Text
-formatTime' s = toText . formatTime defaultTimeLocale s
diff --git a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs
index 7da595b71..79876b8b2 100644
--- a/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs
+++ b/neuron/src/lib/Neuron/Zettelkasten/Zettel/Parser.hs
@@ -8,6 +8,7 @@ module Neuron.Zettelkasten.Zettel.Parser where
 import Control.Monad.Writer
 import Data.Some
 import qualified Data.Text as T
+import Data.Time.DateMayTime (mkDateMayTime)
 import Neuron.Reader.Type
 import Neuron.Zettelkasten.ID
 import Neuron.Zettelkasten.Query.Error
@@ -40,7 +41,7 @@ parseZettel format zreader fn zid s = do
           date = case zid of
             -- We ignore the "data" meta field on legacy Date IDs, which encode the
             -- creation date in the ID.
-            ZettelDateID v _ -> Just $ Meta.mkDateMayTime $ Left v
+            ZettelDateID v _ -> Just $ mkDateMayTime $ Left v
             ZettelCustomID _ -> Meta.date =<< meta
           unlisted = fromMaybe False $ Meta.unlisted =<< meta
           (queries, errors) = runWriter $ extractQueries doc
diff --git a/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs b/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
index 6ce2a7a11..ad75f2c6f 100644
--- a/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
+++ b/neuron/test/Neuron/Zettelkasten/ZettelSpec.hs
@@ -15,6 +15,7 @@ import Neuron.Reader.Type
 import Neuron.Zettelkasten.ID
 import Neuron.Zettelkasten.Zettel
 import Neuron.Zettelkasten.Zettel.Meta
+import Data.Time.DateMayTime
 import Relude
 import Test.Hspec