@using Shogi.Contracts.Api;
@using Shogi.Contracts.Types;
@using System.Text.RegularExpressions;
@inject PromotePrompt PromotePrompt;
@inject IShogiApi ShogiApi;

<GameBoardPresentation OnClickHand="OnClickHand" OnClickTile="OnClickTile" Session="Session" Perspective="Perspective" />

@code {
    [Parameter] public WhichPlayer Perspective { get; set; }
    [Parameter] public Session Session { get; set; }
    private bool IsMyTurn => Session?.BoardState.WhoseTurn == Perspective;
    private string? selectedBoardPosition;
    private WhichPiece? selectedPieceFromHand;

    bool ShouldPromptForPromotion(string position)
    {
        if (Perspective == WhichPlayer.Player1 && Regex.IsMatch(position, ".[7-9]"))
        {
            return true;
        }
        if (Perspective == WhichPlayer.Player2 && Regex.IsMatch(position, ".[1-3]"))
        {
            return true;
        }
        return false;
    }

    async void OnClickTile(Piece? piece, string position)
    {
        if (!IsMyTurn) return;

        if (selectedBoardPosition == null || piece?.Owner == Perspective)
        {
            // Select a position.
            selectedBoardPosition = position;
            return;
        }
        if (selectedBoardPosition == position)
        {
            // Deselect the selected position.
            selectedBoardPosition = null;
            return;
        }
        if (piece == null)
        {
            if (ShouldPromptForPromotion(position) || ShouldPromptForPromotion(selectedBoardPosition))
            {
                PromotePrompt.Show(Session.SessionName, new MovePieceCommand
                    {
                        From = selectedBoardPosition,
                        To = position
                    });
            }
            else
            {
                await ShogiApi.Move(Session.SessionName, new MovePieceCommand
                    {
                        From = selectedBoardPosition,
                        IsPromotion = false,
                        To = position
                    });
            }
        }
    }

    void OnClickHand(Piece piece)
    {
        selectedPieceFromHand = piece.WhichPiece;
    }
}