more resilient research of anchor point for explorer insertion

modules/study/src/main/ExplorerGame.scala

@@ -35,20 +35,19 @@ private final class ExplorerGame(
  }
 
  private def merge(fromNode: RootOrNode, fromPath: Path, game: Node.Root, comment: Comment): Option[(Node, Path)] = {
- val gameNodes = game.mainline.take(lila.explorer.maxPlies).reverse
- val fromNodes = fromNode.mainline.take(lila.explorer.maxPlies - fromNode.ply)
- val fromEndPath = fromNodes.drop(1).foldLeft(fromPath)(_ + _)
- val (path, foundGameNode) = fromNodes.reverse.foldLeft((fromEndPath, none[Node])) {
- case ((path, None), fromNode) =>
- gameNodes.find(_.fen == fromNode.fen) match {
- case Some(gameNode) => path -> gameNode.some
- case None => path.init -> none
+ val gameNodes = game.mainline.dropWhile(_.fen != fromNode.fen) drop 1
+ val (path, foundGameNode) = gameNodes.foldLeft((Path.root, none[Node])) {
+ case ((path, None), gameNode) =>
+ val nextPath = path + gameNode
+ fromNode.children.nodeAt(nextPath) match {
+ case Some(child) => (nextPath, none)
+ case None => (path, gameNode.some)
  }
  case (found, _) => found
  }
- foundGameNode.flatMap(_.children.first).map { nextGameNode =>
+ foundGameNode.map { nextGameNode =>
  val commentedNode = nextGameNode setComment comment
- commentedNode -> path
+ commentedNode -> fromPath.+(path)
  }
  }
 

modules/study/src/main/Path.scala

@@ -14,7 +14,8 @@ case class Path(ids: List[UciCharPair]) extends AnyVal {
 
  def isEmpty = ids.isEmpty
 
- def +(node: Node) = Path(ids :+ node.id)
+ def +(node: Node): Path = Path(ids :+ node.id)
+ def +(more: Path): Path = Path(ids ::: more.ids)
 
  override def toString = ids.mkString
 }