open explorer games not at ply, but at FEN

app/controllers/Analyse.scala

@@ -64,30 +64,46 @@ object Analyse extends LilaController {
   def replay(pov: Pov, userTv: Option[lila.user.User])(implicit ctx: Context) =
     if (HTTPRequest isBot ctx.req) replayBot(pov)
     else GameRepo initialFen pov.game.id flatMap { initialFen =>
-      (env.analyser get pov.game.id) zip
-        (pov.game.simulId ?? Env.simul.repo.find) zip
-        Env.game.crosstableApi(pov.game) flatMap {
-          case ((analysis, simul), crosstable) =>
-            val pgn = Env.api.pgnDump(pov.game, initialFen)
-            Env.api.roundApi.watcher(pov, lila.api.Mobile.Api.currentVersion,
-              tv = none,
-              analysis.map(pgn -> _),
-              initialFenO = initialFen.some,
-              withMoveTimes = true) map { data =>
-                Ok(html.analyse.replay(
-                  pov,
-                  data,
-                  initialFen,
-                  Env.analyse.annotator(pgn, analysis, pov.game.opening, pov.game.winnerColor, pov.game.status, pov.game.clock).toString,
-                  analysis,
-                  analysis filter (_.done) map { a => AdvantageChart(a.infoAdvices, pov.game.pgnMoves, pov.game.startedAtTurn) },
-                  simul,
-                  new TimeChart(pov.game, pov.game.pgnMoves),
-                  crosstable,
-                  userTv,
-                  divider(pov.game, initialFen)))
-              }
-        }
+      RedirectAtFen(pov, initialFen) {
+        (env.analyser get pov.game.id) zip
+          (pov.game.simulId ?? Env.simul.repo.find) zip
+          Env.game.crosstableApi(pov.game) flatMap {
+            case ((analysis, simul), crosstable) =>
+              val pgn = Env.api.pgnDump(pov.game, initialFen)
+              Env.api.roundApi.watcher(pov, lila.api.Mobile.Api.currentVersion,
+                tv = none,
+                analysis.map(pgn -> _),
+                initialFenO = initialFen.some,
+                withMoveTimes = true) map { data =>
+                  Ok(html.analyse.replay(
+                    pov,
+                    data,
+                    initialFen,
+                    Env.analyse.annotator(pgn, analysis, pov.game.opening, pov.game.winnerColor, pov.game.status, pov.game.clock).toString,
+                    analysis,
+                    analysis filter (_.done) map { a => AdvantageChart(a.infoAdvices, pov.game.pgnMoves, pov.game.startedAtTurn) },
+                    simul,
+                    new TimeChart(pov.game, pov.game.pgnMoves),
+                    crosstable,
+                    userTv,
+                    divider(pov.game, initialFen)))
+                }
+          }
+      }
+    }
+
+  private def RedirectAtFen(pov: Pov, initialFen: Option[String])(or: => Fu[Result])(implicit ctx: Context) =
+    get("fen").fold(or) { atFen =>
+      val url = routes.Round.watcher(pov.gameId, pov.color.name)
+      fuccess {
+        chess.Replay.plyAtFen(pov.game.pgnMoves, initialFen, pov.game.variant, atFen).fold(
+          err => {
+            // loginfo(s"RedirectAtFen: $err")
+            println(s"RedirectAtFen: $err")
+            Redirect(url)
+          },
+          ply => Redirect(s"$url#$ply"))
+      }
     }
 
   private def replayBot(pov: Pov)(implicit ctx: Context) =

app/controllers/Importer.scala

@@ -40,19 +40,18 @@ object Importer extends LilaController {
   }
 
   def masterGame(id: String, orientation: String) = Open { implicit ctx =>
+    def redirectAtFen(game: lila.game.Game) = Redirect {
+      val url = routes.Round.watcher(game.id, orientation).url
+      s"$url?fen=${~get("fen")}"
+    }
     lila.game.GameRepo game id flatMap {
-      case Some(game) => fuccess(Redirect(routes.Round.watcher(game.id, game.firstPlayer.color.name)))
+      case Some(game) => fuccess(redirectAtFen(game))
       case _ => Env.explorer.fetchPgn(id) flatMap {
         case None => fuccess(NotFound)
         case Some(pgn) => env.importer(
           lila.importer.ImportData(pgn, none),
           user = "lichess".some,
-          forceId = id.some) map { game =>
-            Redirect {
-              val url = routes.Round.watcher(game.id, orientation).url
-              s"$url#${~getInt("ply")}"
-            }
-          }
+          forceId = id.some) map redirectAtFen
       }
     }
   }

modules/chess

@@ -1 +1 @@
-Subproject commit aa3ca3018378579ed4ca58093633e77af6766dce
+Subproject commit 18edd6eb2de3b408506ff7df194d73fcb8fce3a7

ui/analyse/src/explorer/explorerView.js

@@ -87,9 +87,9 @@ function showGameTable(ctrl, type, games) {
         if (!$tr.length) return;
         var orientation = ctrl.chessground.data.orientation;
         if (ctrl.explorer.config.data.db.selected() === 'lichess')
-          window.open('/' + $tr.data('id') + '/' + orientation + '#' + ctrl.vm.step.ply, '_blank');
+          window.open('/' + $tr.data('id') + '/' + orientation + '?fen=' + ctrl.vm.step.fen, '_blank');
         else
-          window.open('/import/master/' + $tr.data('id') + '/' + orientation + '?ply=' + ctrl.vm.step.ply, '_blank');
+          window.open('/import/master/' + $tr.data('id') + '/' + orientation + '?fen=' + ctrl.vm.step.fen, '_blank');
       }
     }, games.map(function(game) {
       return m('tr', {