using System;
using PiCross;
using Cells;
using System.Windows.Input;

namespace ViewModel
{
    public class SquareViewModel
    {
        private readonly IPlayablePuzzleSquare square;

        private readonly Left left;
        private readonly Right right;

        public SquareViewModel(IPlayablePuzzleSquare square)
        {
            this.square = square;
            left = new Left(this);
            right = new Right(this);
        }

        // Square
        public Cell<Square> Contents
        {
            get
            {
                return square.Contents;
            }
        }

        #region Click Commands
        private class Left : ICommand
        {
            private readonly SquareViewModel vm;

            public Left(SquareViewModel vm)
            {
                CanExecuteChanged += (a, b) => { };
                this.vm = vm;
            }

            public event EventHandler CanExecuteChanged;

            public bool CanExecute(object parameter)
            {
                return true;
            }

            public void Execute(object parameter)
            {
                if (vm.square.Contents.Value == Square.UNKNOWN || vm.square.Contents.Value == Square.EMPTY)
                {
                    vm.square.Contents.Value = Square.FILLED;
                }
                else
                {
                    if (vm.square.Contents.Value == Square.FILLED)
                    {
                        vm.square.Contents.Value = Square.UNKNOWN;
                    }
                }
            }
        }
        private class Right : ICommand
        {
            private readonly SquareViewModel vm;

            public Right(SquareViewModel vm)
            {
                CanExecuteChanged += (a, b) => { };
                this.vm = vm;
            }

            public event EventHandler CanExecuteChanged;

            public bool CanExecute(object parameter)
            {
                return true;
            }

            public void Execute(object parameter)
            {
                if (vm.square.Contents.Value == Square.UNKNOWN || vm.square.Contents.Value == Square.FILLED)
                {
                    vm.square.Contents.Value = Square.EMPTY;
                }
                else
                {
                    if (vm.square.Contents.Value == Square.EMPTY)
                    {
                        vm.square.Contents.Value = Square.UNKNOWN;
                    }
                }
            }
        }

        public ICommand LCC
        {
            get { return left; }
        }

        public ICommand RCC
        {
            get { return right; }
        }
    }

    #endregion
}