From f2451697db288b46941461746d2716f9d5adccb7 Mon Sep 17 00:00:00 2001
From: Dmitry Zuikov <dzuikov@gmail.com>
Date: Wed, 17 Apr 2024 09:56:24 +0300
Subject: [PATCH] wip

---
 hbs2-git/git-hbs2/Main.hs                     | 14 ++---
 .../HBS2/Git/Client/State.hs                  | 58 +++++++++++++------
 .../HBS2/Git/Data/Tx/Index.hs                 |  4 ++
 3 files changed, 52 insertions(+), 24 deletions(-)

diff --git a/hbs2-git/git-hbs2/Main.hs b/hbs2-git/git-hbs2/Main.hs
index 8b75ff31..96f7be57 100644
--- a/hbs2-git/git-hbs2/Main.hs
+++ b/hbs2-git/git-hbs2/Main.hs
@@ -8,6 +8,7 @@ import HBS2.Git.Client.Import
 import HBS2.Git.Client.State
 
 import HBS2.Data.Types.SignedBox
+import HBS2.Git.Data.RepoHead
 import HBS2.Git.Data.RefLog
 import HBS2.Git.Local.CLI qualified as Git
 import HBS2.Git.Data.Tx.Git qualified as TX
@@ -182,7 +183,7 @@ pManifestList :: GitPerks m => Parser (GitCLI m ())
 pManifestList = do
   what <- argument pLwwKey (metavar "LWWREF")
   pure do
-    heads <- withState $ selectRepoHeadsFor what
+    heads <- withState $ selectRepoHeadsFor DESC what
     sto   <- getStorage
     for_ heads $ \h -> runMaybeT do
 
@@ -339,13 +340,12 @@ pGenRepoIndex :: GitPerks m => Parser (GitCLI m ())
 pGenRepoIndex = do
   what <- argument pLwwKey (metavar "LWWREF")
   pure do
-    withState do
-      idx <- selectRepoIndexEntryFor what
-               `orDie` "repo head not found"
+    hd <- withState $ selectRepoIndexEntryFor what
+            >>= orThrowUser "no decent repo head data found"
 
-      liftIO $ print idx
-
-    pure ()
+    seq <- getEpoch
+    let tx = GitIndexTx what seq (GitIndexRepoDefine hd)
+    liftIO $ LBS.putStr (serialise tx)
 
 main :: IO ()
 main = do
diff --git a/hbs2-git/hbs2-git-client-lib/HBS2/Git/Client/State.hs b/hbs2-git/hbs2-git-client-lib/HBS2/Git/Client/State.hs
index 6f607dda..387accb8 100644
--- a/hbs2-git/hbs2-git-client-lib/HBS2/Git/Client/State.hs
+++ b/hbs2-git/hbs2-git-client-lib/HBS2/Git/Client/State.hs
@@ -22,7 +22,19 @@ import DBPipe.SQLite
 import Data.Maybe
 import Data.List qualified as List
 import Text.InterpolatedString.Perl6 (qc)
+import Data.Text qualified as Text
 import Data.Word
+import Data.Coerce
+
+import Streaming.Prelude qualified as S
+
+data SortOrder = ASC | DESC
+
+newtype SQL a = SQL a
+
+instance Pretty (SQL SortOrder) where
+  pretty (SQL ASC) = "ASC"
+  pretty (SQL DESC) = "DESC"
 
 newtype Base58Field a = Base58Field { fromBase58Field :: a }
                         deriving stock (Eq,Ord,Generic)
@@ -388,45 +400,57 @@ SELECT hash, seq, reflog FROM lww
 
 
 selectRepoHeadsFor :: (MonadIO m, HasStorage m)
-                    => LWWRefKey 'HBS2Basic
+                    => SortOrder
+                    -> LWWRefKey 'HBS2Basic
                     -> DBPipeM m [TaggedHashRef RepoHead]
 
-selectRepoHeadsFor  what = do
+selectRepoHeadsFor order what = do
   let q = [qc|
 SELECT t.head
 FROM lww l join tx t on l.reflog = t.reflog
 WHERE l.hash = ?
-ORDER BY t.seq ASC
+ORDER BY t.seq {pretty (SQL order)}
 |]
 
   select @(Only (TaggedHashRef RepoHead)) q (Only $ Base58Field what)
    <&> fmap fromOnly
 
 
+instance (Monad m, HasStorage m) => HasStorage (DBPipeM m) where
+  getStorage = lift getStorage
+
 selectRepoIndexEntryFor :: (MonadIO m, HasStorage m)
                         => LWWRefKey 'HBS2Basic
                         -> DBPipeM m (Maybe GitIndexRepoDefineData)
 
 selectRepoIndexEntryFor what = runMaybeT do
-  let q = [qc|
-SELECT l.hash, t.head
-FROM lww l join tx t on l.reflog = t.reflog
-WHERE l.hash = ?
-ORDER BY l.seq DESC
-LIMIT 1
-|]
 
-  (k,rh) <- lift (select @(LWWRefKey 'HBS2Basic, HashRef) q (Only $ Base58Field what))
-              <&> listToMaybe >>= toMPlus
+  headz <- lift $ selectRepoHeadsFor DESC what
 
-  sto <- lift $ lift getStorage
+  rhh <- S.head_ do
+            for_ headz $ \ha -> do
+              rh' <- lift $ loadRepoHead ha
+              for_ rh' $ \rh -> do
+                when (notEmpty $ _repoManifest  rh) do
+                  S.yield rh
 
-  repohead <- runExceptT (readFromMerkle sto (SimpleKey (fromHashRef rh)))
-                >>= toMPlus
-                <&> deserialiseOrFail @RepoHead
-                >>= toMPlus
+
+  repohead <- toMPlus rhh
 
   pure $ GitIndexRepoDefineData (GitIndexRepoName $ _repoHeadName repohead)
                                 (GitIndexRepoBrief $ _repoHeadBrief repohead)
 
 
+  where
+    notEmpty s = maybe 0 Text.length s > 0
+
+loadRepoHead :: (HasStorage m, MonadIO m) => TaggedHashRef RepoHead -> m (Maybe RepoHead)
+loadRepoHead rh = do
+  sto <- getStorage
+  runMaybeT do
+    runExceptT (readFromMerkle sto (SimpleKey (coerce rh)))
+       >>= toMPlus
+       <&> deserialiseOrFail @RepoHead
+       >>= toMPlus
+
+
diff --git a/hbs2-git/hbs2-git-client-lib/HBS2/Git/Data/Tx/Index.hs b/hbs2-git/hbs2-git-client-lib/HBS2/Git/Data/Tx/Index.hs
index 95647335..c38dd666 100644
--- a/hbs2-git/hbs2-git-client-lib/HBS2/Git/Data/Tx/Index.hs
+++ b/hbs2-git/hbs2-git-client-lib/HBS2/Git/Data/Tx/Index.hs
@@ -77,6 +77,10 @@ data GitIndexTx s =
   }
   deriving stock (Generic)
 
+instance ForGitIndex s => Serialise (GitIndexTx s)
+instance Serialise GitIndexRepoDefineData
+instance Serialise GitIndexEntry
+
 instance ForGitIndex s => Pretty (GitIndexTx s) where
   pretty GitIndexTx{..} = case gitIndexTxPayload of
     GitIndexRepoDefine{}  -> "git-repo-define" <+> pretty gitIndexTxRef