using System;
using System.Linq;

namespace Life.Automaton
{
    [Serializable]
    public class GameOfLife : IAutomaton
    {
        [Serializable]
        public class StandardRule : IRule
        {
            private string survive;
            private string born;

            public StandardRule(string born, string survive)
            {
                this.born = born;
                this.survive = survive;
            }

            bool WillSurvive(int neighbours) => survive.Contains(neighbours.ToString());
            bool WillBorn(int neighbours) => born.Contains(neighbours.ToString());
            
            public Cell[,] Next(IField field)
            {
                var @new = new Cell[field.Size.Width, field.Size.Height];

                for (int i = 0; i < field.Size.Width; i++)
                {
                    for (int j = 0; j < field.Size.Height; j++)
                    {
                        var neighbours = field.Neighbours(i, j).Count(c => c.IsAlive);
                        
                        @new[i,j] = new Cell
                        {
                            IsAlive = field[i,j].IsAlive ? WillSurvive(neighbours) : WillBorn(neighbours)
                        };
                    }
                }
                
                return @new;
            }
        }
        
        public GameOfLife(int width, int height)
        {
            Field = new MooreField(width, height);
        }

        public IRule Rule { get; set; } = new StandardRule("3", "32");

        public int Iteration { get; private set; }

        public IField Field { get; private set; }

        public void Advance()
        {
            Field.Transform(Rule);
            Iteration++;
        }

        public void ReplaceField(IField field)
        {
            Field = field;
        }
    }
}