namespace Day10;

public record Tile(char Pipe, GridPoint Position)
{
    private int? _display;

    public bool HasDisplay => _display != null;
    public string? Display => _display == null ? Pipe.ToString() : (_display % 10).ToString();
    
    public IEnumerable<GridPoint> GetConnections()
    {
        switch (Pipe)
        {
            case '|':
                yield return Position.North();
                yield return Position.South();
                break;
            case '-':
                yield return Position.East();
                yield return Position.West();
                break;
            case 'L':
                yield return Position.North();
                yield return Position.East();
                break;
            case 'J':
                yield return Position.North();
                yield return Position.West();
                break;
            case '7':
                yield return Position.South();
                yield return Position.West();
                break;
            case 'F':
                yield return Position.South();
                yield return Position.East();
                break;
            case 'S':
                yield return Position.North();
                yield return Position.East();
                yield return Position.South();
                yield return Position.West();
                break;
            default:
                yield break;
        }
    }

    public void SetDisplay(int display)
    {
        _display = display;
    }

    public bool ConnectsTo(GridPoint other)
    {
        return Pipe == 'S' || GetConnections().Any(c => c == other);
    }
}