using System;
using System.Drawing;
using System.Drawing.Imaging;

namespace Hncore.Infrastructure.Common
{
    public class ValidateCodeHelper
    {
        public static string MakeCode(int length = 4)
        {
            char[] allCharArray = new char[] { '2', '3', '4', '5', '6', '7', '8', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J', 'K', 'L', 'M', 'N', 'P', 'Q', 'R', 'S', 'T', 'U', 'W', 'X', 'Y', 'Z' };
            string randomCode = "";
            int temp = -1;

            Random rand = new Random();
            for (int i = 0; i < length; i++)
            {
                if (temp != -1)
                {
                    rand = new Random(i * temp * ((int)DateTime.Now.Ticks));
                }
                int t = rand.Next(allCharArray.Length);
                if (temp == t)
                {
                    return MakeCode(length);
                }
                temp = t;
                randomCode += allCharArray[t];
            }
            return randomCode;
        }
        public static string MakeNumCode(int length = 4)
        {
            char[] allCharArray = new char[] { '1','2', '3', '4', '5', '6', '7', '8','9'};
            string randomCode = "";
            int temp = -1;

            Random rand = new Random();
            for (int i = 0; i < length; i++)
            {
                if (temp != -1)
                {
                    rand = new Random(i * temp * ((int)DateTime.Now.Ticks));
                }
                int t = rand.Next(allCharArray.Length);
                if (temp == t)
                {
                    return MakeNumCode(length);
                }
                temp = t;
                randomCode += allCharArray[t];
            }
            return randomCode;
        }

        public static string MakeCharCode(int length = 4)
        {
            char[] allCharArray = new char[] { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J', 'K', 'L', 'M', 'N', 'P', 'Q', 'R', 'S', 'T', 'U', 'W', 'X', 'Y', 'Z' };
            string randomCode = "";
            int temp = -1;

            Random rand = new Random();
            for (int i = 0; i < length; i++)
            {
                if (temp != -1)
                {
                    rand = new Random(i * temp * ((int)DateTime.Now.Ticks));
                }
                int t = rand.Next(allCharArray.Length);
                if (temp == t)
                {
                    return MakeCharCode(length);
                }
                temp = t;
                randomCode += allCharArray[t];
            }
            return randomCode;
        }

        public static byte[] GenerateCodeImg(string code)
        {
            int Gheight = (int)(code.Length * 15) + 10;

            //gheight为图片宽度,根据字符长度自动更改图片宽度
            using (var img = new Bitmap(Gheight, 22))
            {
                using (var g = Graphics.FromImage(img))
                {
                    SolidBrush whiteBrush = new SolidBrush(Color.White);
                    g.FillRectangle(whiteBrush, 0, 0, Gheight, 22);
                    int i = 0;
                    foreach (char ch in code.ToCharArray())
                    { 
                        g.DrawString(ch.ToString(),
                            new Font("Arial", 13, FontStyle.Italic),
                            new SolidBrush(Color.FromArgb(0, 0, 0)),
                            i * 15,
                            0);
                        i++;
                    }

                    //在矩形内绘制字串（字串，字体，画笔颜色，左上x.左上y）
                    System.IO.MemoryStream ms = new System.IO.MemoryStream();
                    img.Save(ms, ImageFormat.Jpeg);
                    return ms.ToArray();
                }
            }
        }
    }
}