using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace _54.Spiral_Matrix
{
    class Program
    {
        static void Main(string[] args)
        {

            /* int[][] matrix = new int[3][];

             matrix[0] = new int[3] { 1, 2, 3 };
             matrix[1] = new int[3] { 4, 5, 6 };
             matrix[2] = new int[3] { 7, 8, 9 };*/
            int[][] matrix = new int[3][];

            matrix[0] = new int[4] { 1, 2, 3, 4 };
            matrix[1] = new int[4] { 5, 6, 7, 8 };
            matrix[2] = new int[4] { 9, 10, 11, 12 };

            var result = SpiralOrder(matrix);

            foreach (var item in result)
            {
                Console.Write($"{item} ");
            }

            Console.Read();
        }

        public static IList<int> SpiralOrder(int[][] matrix)
        {
            if (matrix == null)
                return null;

            IList<int> spiral = new List<int>();

            int maxRows = matrix.Length;

            if (maxRows == 0)
            {
                return spiral;
            }

            int maxColumns = matrix[0].Length;
            int maxSize = maxRows * maxColumns;
            int startColumn = 0;
            int startRow = 0;
            int currentColumn = 0;
            int currentRow = 0;

            int count = 0;

            int rightDirection = 1;
            int downDirection = 0;

            while (count < maxSize)
            {
                spiral.Add(matrix[currentRow][currentColumn]);

                if (rightDirection == 1 && downDirection == 0)
                {
                    currentColumn++;

                    if (currentColumn >= maxColumns)
                    {
                        currentColumn--;
                        maxColumns--;
                        currentRow++;
                        startRow++;

                        downDirection = 1;
                        rightDirection = 0;
                    }
                }
                else if (rightDirection == 0 && downDirection == 1)
                {
                    currentRow++;

                    if (currentRow >= maxRows)
                    {
                        currentRow--;
                        maxRows--;
                        currentColumn--;

                        downDirection = 0;
                        rightDirection = -1;
                    }
                }
                else if (rightDirection == -1 && downDirection == 0)
                {
                    currentColumn--;

                    if (currentColumn < startColumn)
                    {
                        currentRow--;
                        currentColumn++;

                        downDirection = -1;
                        rightDirection = 0;
                    }
                }
                else if (rightDirection == 0 && downDirection == -1)
                {
                    currentRow--;

                    if (currentRow < startRow)
                    {
                        currentRow++;
                        startColumn++;
                        currentColumn++;

                        downDirection = 0;
                        rightDirection = 1;
                    }
                }

                count++;
            }

            return spiral;
        }
    }
}