//
//  MoveTree+Deprecated.swift
//  ChessKit
//

extension MoveTree {
  /// Returns the move at the specified index.
  ///
  /// - parameter index: The move index to query.
  /// - returns: The move at the given index, or `nil` if no
  /// move exists at that index.
  ///
  /// This value can also be accessed using a subscript on
  /// the ``MoveTree`` directly,
  /// e.g. `tree[.init(number: 2, color: .white)]`
  @available(*, deprecated, renamed: "subscript(_:)")
  public func move(at index: Index) -> Move? {
    dictionary[index]?.move
  }

  /// Returns the index of the previous move given an `index`.
  @available(
    *, deprecated,
    renamed: "index(before:)",
    message: "Use index(before:) to obtain the previous index or hasIndex(before:) to check if a valid previous index exists."
  )
  public func previousIndex(for index: Index) -> Index? {
    if index == minimumIndex.next {
      minimumIndex
    } else {
      dictionary[index]?.previous?.index
    }
  }

  /// Returns the index of the next move given an `index`.
  @available(
    *, deprecated,
    renamed: "index(after:)",
    message: "Use index(after:) to obtain the next index or hasIndex(after:) to check if a valid next index exists."
  )
  public func nextIndex(for index: Index) -> Index? {
    if index == minimumIndex {
      dictionary[minimumIndex.next]?.index
    } else {
      dictionary[index]?.next?.index
    }
  }
}