puzzle of the day on homepage

app/Env.scala

@@ -26,7 +26,8 @@ final class Env(
     relations = Env.relation.api,
     leaderboard = Env.user.cached.topRatingDay.apply,
     progress = Env.user.cached.topProgressDay.apply,
-    timelineEntries = Env.timeline.getter.userEntries _)
+    timelineEntries = Env.timeline.getter.userEntries _,
+    dailyPuzzle = Env.puzzle.daily)
 
   lazy val userInfo = mashup.UserInfo(
     countUsers = () => Env.user.countEnabled,

app/actor/Renderer.scala

@@ -33,5 +33,8 @@ private[app] final class Renderer extends Actor {
 
     case lila.tournament.actorApi.TournamentTable(tours) =>
       sender ! V.tournament.createdTable(tours)
+
+    case lila.puzzle.RenderDaily(puzzle, fen, lastMove) =>
+      sender ! V.puzzle.daily(puzzle, fen, lastMove)
   }
 }

app/controllers/Lobby.scala

@@ -32,9 +32,9 @@ object Lobby extends LilaController {
       tours = TournamentRepo.createdUnprotected,
       filter = Env.setup.filter
     ).map(_.fold(Redirect(_), {
-        case (preload, entries, posts, tours, featured, leaderboard, progress) =>
+        case (preload, entries, posts, tours, featured, leaderboard, progress, puzzle) =>
           val response = status(html.lobby.home(
-            Json stringify preload, entries, posts, tours, featured, leaderboard, progress
+            Json stringify preload, entries, posts, tours, featured, leaderboard, progress, puzzle
           ))
           // the session cookie is required for anon lobby filter storage
           ctx.req.session.data.contains(LilaCookie.sessionId).fold(

app/mashup/Preload.scala

@@ -7,17 +7,17 @@ import play.api.libs.json.{ Json, JsObject, JsArray }
 import play.api.mvc.Call
 
 import controllers.routes
+import lila.api.Context
 import lila.forum.PostLiteView
 import lila.game.{ Game, GameRepo, Featured }
 import lila.lobby.actorApi.GetOpen
 import lila.lobby.{ Hook, HookRepo }
+import lila.relation.RelationApi
 import lila.setup.FilterConfig
 import lila.socket.History
 import lila.timeline.Entry
 import lila.tournament.Created
 import lila.user.User
-import lila.api.Context
-import lila.relation.RelationApi
 import makeTimeout.large
 
 final class Preload(
@@ -27,9 +27,10 @@ final class Preload(
     relations: RelationApi,
     leaderboard: Int => Fu[List[User]],
     progress: Int => Fu[List[User]],
-    timelineEntries: String => Fu[List[Entry]]) {
+    timelineEntries: String => Fu[List[Entry]],
+    dailyPuzzle: () => Fu[Option[lila.puzzle.DailyPuzzle]]) {
 
-  private type RightResponse = (JsObject, List[Entry], List[PostLiteView], List[Created], Option[Game], List[User], List[User])
+  private type RightResponse = (JsObject, List[Entry], List[PostLiteView], List[Created], Option[Game], List[User], List[User], Option[lila.puzzle.DailyPuzzle])
   private type Response = Either[Call, RightResponse]
 
   def apply(
@@ -44,13 +45,14 @@ final class Preload(
       (ctx.userId ?? timelineEntries) zip
       leaderboard(10) zip
       progress(10) zip
+      dailyPuzzle() zip
       filter map {
-        case ((((((((hooks, posts), tours), feat), blocks), entries), leaderboard), progress), filter) =>
+        case (((((((((hooks, posts), tours), feat), blocks), entries), leaderboard), progress), puzzle), filter) =>
           (Right((Json.obj(
             "version" -> history.version,
             "pool" -> JsArray(hooks map (_.render)),
             "filter" -> filter.render,
             "blocks" -> blocks
-          ), entries, posts, tours, feat, leaderboard, progress)))
+          ), entries, posts, tours, feat, leaderboard, progress, puzzle)))
       }
 }

app/views/lobby/home.scala.html

@@ -1,4 +1,4 @@
-@(preload: String, userTimeline: List[lila.timeline.Entry], forumRecent: List[lila.forum.PostLiteView], tours: List[lila.tournament.Created], featured: Option[Game], leaderboard: List[User], progress: List[User])(implicit ctx: Context)
+@(preload: String, userTimeline: List[lila.timeline.Entry], forumRecent: List[lila.forum.PostLiteView], tours: List[lila.tournament.Created], featured: Option[Game], leaderboard: List[User], progress: List[User], puzzle: Option[lila.puzzle.DailyPuzzle])(implicit ctx: Context)
 
 @underchat = {
 <div id="featured_game" title="@trans.watchLichessTV()">
@@ -46,7 +46,7 @@ themepicker = true) {
   @translationCall.map(i18n.callBox(_))
 </div>
 <div class="clearfix lichess_homepage">
-  <div class="lichess_board_wrap lichess_player_white">
+  <div class="lichess_board_wrap">
     <div id="hooks_wrap">
       <div class="tabs">
         <a data-tab="list" class="list">@trans.list()</a>
@@ -78,6 +78,15 @@ themepicker = true) {
       <a class="lichess_button button config_@b.code" href="@b.route" onclick="return false" title="@b.title()">@b.name()</a>
       }
     </div>
+    @puzzle.map { p =>
+    <div id="daily_puzzle">
+      @p.html
+      <div class="vstext">
+        @trans.puzzleOfTheDay()<br />
+        @trans.findTheBestMoveForColor(p.color.name)
+      </div>
+    </div>
+    }
   </div>
   @lobby.undertable(forumRecent, tours, leaderboard, progress)
 </div>

app/views/puzzle/daily.scala.html

@@ -0,0 +1,7 @@
+@(p: lila.puzzle.Puzzle, fen: String, lastMove: String)
+
+<a href="@routes.Puzzle.show(p.id)"
+  class="mini_board parse_fen"
+  data-color="@p.color"
+  data-fen="@fen"
+  data-lastmove="@lastMove"></a>

conf/messages

@@ -272,6 +272,7 @@ toTrackYourProgress=To track your progress:
 trainingSignupExplanation=Lichess will provide puzzles that match your ability, making for better training sessions.
 recentlyPlayedPuzzles=Recently played puzzles
 puzzleId=Puzzle %s
+puzzleOfTheDay=Puzzle of the day
 goodMove=Good move
 butYouCanDoBetter=But you can do better.
 bestMove=Best move!

modules/puzzle/src/main/Daily.scala

@@ -0,0 +1,65 @@
+package lila.puzzle
+
+import scala.concurrent.duration._
+
+import akka.actor.{ ActorSelection, Scheduler }
+import akka.pattern.ask
+import org.joda.time.DateTime
+import reactivemongo.bson.BSONDocument
+
+import lila.db.BSON.BSONJodaDateTimeHandler
+import lila.db.Types.Coll
+
+private[puzzle] final class Daily(
+    coll: Coll,
+    renderer: ActorSelection,
+    scheduler: Scheduler) {
+
+  private val cache =
+    lila.memo.AsyncCache.single[Option[DailyPuzzle]](f = find, timeToLive = 30 minutes)
+
+  def apply(): Fu[Option[DailyPuzzle]] = cache apply true
+
+  private def find: Fu[Option[DailyPuzzle]] = findCurrent orElse findNew flatMap {
+    case Some(puzzle) => makeDaily(puzzle)
+    case None =>
+      scheduler.scheduleOnce(10.seconds)(cache.clear)
+      fuccess(none)
+  }
+
+  private def makeDaily(puzzle: Puzzle): Fu[Option[DailyPuzzle]] = {
+    import chess.format.{ UciMove, Forsyth }
+    import makeTimeout.short
+    ~(for {
+      sit1 <- Forsyth << puzzle.fen
+      move <- puzzle.history.lastOption
+      uci <- UciMove(move)
+      sit2 <- sit1.move(uci.orig, uci.dest, uci.promotion).toOption map (_.situationAfter)
+      fen = Forsyth >> sit2
+    } yield renderer ? RenderDaily(puzzle, fen, move) map {
+      case html: play.api.templates.Html => DailyPuzzle(html, puzzle.color).some
+    })
+  } recover {
+    case e: Exception =>
+      play.api.Logger("daily puzzle").warn(e.getMessage)
+      none
+  }
+
+  private def findCurrent = coll.find(
+    BSONDocument("day" -> BSONDocument("$gt" -> DateTime.now.minusDays(1)))
+  ).one[Puzzle]
+
+  private def findNew = coll.find(
+    BSONDocument("day" -> BSONDocument("$exists" -> false))
+  ).sort(BSONDocument("vote.sum" -> -1)).one[Puzzle] flatMap {
+      case Some(puzzle) => coll.update(
+        BSONDocument("_id" -> puzzle.id),
+        BSONDocument("$set" -> BSONDocument("day" -> DateTime.now))
+      ) inject puzzle.some
+      case None => fuccess(none)
+    }
+}
+
+case class DailyPuzzle(html: play.api.templates.Html, color: chess.Color)
+
+case class RenderDaily(puzzle: Puzzle, fen: String, lastMove: String)

modules/puzzle/src/main/Env.scala

@@ -1,6 +1,6 @@
 package lila.puzzle
 
-import akka.actor.{ ActorSystem, Props }
+import akka.actor.{ ActorSelection, ActorSystem, Props }
 import com.typesafe.config.Config
 
 import lila.common.PimpedConfig._
@@ -8,6 +8,7 @@ import lila.common.PimpedConfig._
 final class Env(
     config: Config,
     db: lila.db.Env,
+    renderer: ActorSelection,
     system: ActorSystem) {
 
   private val settings = new {
@@ -32,6 +33,12 @@ final class Env(
 
   lazy val forms = DataForm
 
+  lazy val daily = new Daily(
+    puzzleColl,
+    renderer,
+    system.scheduler
+  ).apply _
+
   private[puzzle] lazy val puzzleColl = db(CollectionPuzzle)
   private[puzzle] lazy val attemptColl = db(CollectionAttempt)
 }
@@ -41,5 +48,6 @@ object Env {
   lazy val current: Env = "[boot] puzzle" describes new Env(
     config = lila.common.PlayApp loadConfig "puzzle",
     db = lila.db.Env.current,
+    renderer = lila.hub.Env.current.actor.renderer,
     system = lila.common.PlayApp.system)
 }

public/stylesheets/board.css

@@ -513,7 +513,7 @@ div.under_chat {
   width: 224px;
   margin-left: -28px;
   position: absolute;
-  top: 530px;
+  top: 529px;
   left: 0;
 }
 div.under_chat .watchtv {

public/stylesheets/common.css

@@ -1250,6 +1250,15 @@ div.vstext .right {
   float: right;
   text-align: right;
 }
+#daily_puzzle {
+  width: 224px;
+  position: absolute;
+  top: 529px;
+  left: 0;
+}
+#daily_puzzle > div.vstext {
+  text-align: center;
+}
 div.extra_top {
   float: right;
   margin: 20px 20px 0 0;