using Godot;

public class Player
{
	private VirtualBoard board;
	private SelectedPiece selectedNode;
	private MoveRecords<VirtualPiece> moveRecords;

	public enum PlayerType {
		Human,
		AI
	}

	public Player(VirtualBoard board, PlayerType type = PlayerType.Human)
	{
		this.board = board;
		this.selectedNode = new SelectedPiece(board);
		this.moveRecords = new MoveRecords<VirtualPiece>(onUndoRecordCallback: (newNode, oldNode, newPos, oldPos) => {
			GD.Print("Undo: ", newNode, "->", oldNode, ":", newPos, "->", oldPos);
			VirtualPiece newPiece = newNode;
			VirtualPiece oldPiece = oldNode;
			this.board.MovePiece(newPos, oldPos);
			if (newPiece != null) {
				this.board.InsertPiece(newPiece, newPos);
			}
		});
	}

	public void HandleBoardPosClick(Vector2 clickPos) {
		if (board.ArrPosOutOfRange(clickPos)) return;
		GD.Print($"VirtualBoard {clickPos} clicked");
		VirtualPiece clickChess = board.GetPiece(clickPos);

		if (!selectedNode.HasSelected()) {
			// Select piece
			if (clickChess == null) {
				// selectedNode.Clear();
				return;
			}
			selectedNode.SetPos(clickPos);
		} else if (clickChess == selectedNode.GetPiece()) {
			// Unselect piece
			selectedNode.Clear();
		} else {
			// Move piece
			GD.Print("default MoveFunc Move: ", selectedNode.GetPos(), "->", clickPos);
			MoveAndRecord(clickPos, selectedNode.GetPos());
		}
	}

	public void MoveAndRecord(Vector2 toPos, Vector2 fromPos) {
		GD.Print($"{fromPos} move to {toPos}");
		VirtualPiece toChess = board.GetPiece(toPos);
        VirtualPiece fromChess = board.GetPiece(fromPos);
		fromChess?.Selected(false);

		VirtualPiece NowNode;
        if (toChess != null) {
			NowNode = toChess;
            board.RemovePiece(toPos);
        } else {
			NowNode = toChess;
		}
		moveRecords.AddRecord(NowNode, fromChess, toPos, fromPos);
        board.MovePiece(fromPos, toPos);

		selectedNode.Clear();
	}

	public void Undo() {
		// ChessPiece selected = selectedNode.GetPiece();
		// selected?.DeSelected();
		selectedNode.Clear();
		moveRecords.Undo();
	}

	public void ReInit() {
		moveRecords.Clear();
		board.Clear();
		selectedNode.Clear();
		// board.InitChessBoard();
	}

	private class SelectedPiece
	{
		// Called when the node enters the scene tree for the first time.
		private Vector2 selectedNodePos = Vector2.Inf;
		private VirtualPiece piece;
		private VirtualBoard board;

		public SelectedPiece(VirtualBoard board)
		{
			this.board = board;
		}

		public void Clear()
		{
			if (selectedNodePos != Vector2.Inf) {
				selectedNodePos = Vector2.Inf;
				piece.Selected(false);
			}
		}

		public void SetPos(Vector2 pos)
		{
			// piece = board.GetNodeFromBoard(pos) as VirtualPiece;
			selectedNodePos = pos;
			piece = board.GetPiece(selectedNodePos);
			piece.Selected(true);
		}

		public VirtualPiece GetPiece()
		{
			return piece;
		}

		public Vector2 GetPos()
		{
			return selectedNodePos;
		}

		public bool HasSelected()
		{
			return selectedNodePos != Vector2.Inf;
		}
	}
}