using Admin.Core.Common.Attributes;
using Admin.Core.Common.Cache;
using Newtonsoft.Json;
using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.IO;
using System.Threading.Tasks;
namespace Admin.Tools.Captcha
{
///
/// 滑块拼图验证
///
[SingleInstance]
public class SlideJigsawCaptcha : ICaptcha
{
private readonly ICache _cache;
public SlideJigsawCaptcha(ICache cache)
{
_cache = cache;
}
///
/// Bitmap转为base64编码的文本
///
///
///
private string ImgToBase64String(Bitmap bmp)
{
try
{
MemoryStream ms = new MemoryStream();
bmp.Save(ms, ImageFormat.Png);
byte[] arr = new byte[ms.Length];
ms.Position = 0;
ms.Read(arr, 0, (int)ms.Length);
ms.Close();
return Convert.ToBase64String(arr);
}
catch
{
return null;
}
}
///
/// 根据模板生成拼图
///
///
///
///
///
///
private Bitmap CutByTemplate(Bitmap baseImage, Bitmap templateImage, int x, int y)
{
Bitmap newImage = new Bitmap(templateImage.Width, baseImage.Height, PixelFormat.Format32bppRgb);
newImage.MakeTransparent();
int xLength = templateImage.Width;
int yLength = templateImage.Height;
// 模板图像宽度
for (int i = 0; i < xLength; i++)
{
// 模板图片高度
for (int j = 0; j < yLength; j++)
{
// 如果模板图像当前像素点不是透明色 copy源文件信息到目标图片中
int rgb = templateImage.GetPixel(i, j).ToArgb();
if (rgb < 0)
{
Color oriImageColor = baseImage.GetPixel(x + i, y + j);
newImage.SetPixel(i, y + j, oriImageColor);
//抠图区域半透明
baseImage.SetPixel(x + i, y + j, Color.FromArgb(120, oriImageColor.R, oriImageColor.G, oriImageColor.B));
}
//防止数组越界判断
if (i == (xLength - 1) || j == (yLength - 1))
{
continue;
}
int rightRgb = templateImage.GetPixel(i + 1, j).ToArgb();
int downRgb = templateImage.GetPixel(i, j + 1).ToArgb();
//描边处理,,取带像素和无像素的界点,判断该点是不是临界轮廓点,如果是设置该坐标像素是白色
if ((rgb >= 0 && rightRgb < 0) || (rgb < 0 && rightRgb >= 0) || (rgb >= 0 && downRgb < 0) || (rgb < 0 && downRgb >= 0))
{
newImage.SetPixel(i, y + j, Color.White);
baseImage.SetPixel(x + i, y + j, Color.White);
}
}
}
return newImage;
}
///
/// 根据模板生成干扰图
///
///
///
///
///
private void InterferenceByTemplate(Bitmap baseImage, Bitmap templateImage, int x, int y)
{
int xLength = templateImage.Width;
int yLength = templateImage.Height;
// 模板图像宽度
for (int i = 0; i < xLength; i++)
{
// 模板图片高度
for (int j = 0; j < yLength; j++)
{
// 如果模板图像当前像素点不是透明色 copy源文件信息到目标图片中
int rgb = templateImage.GetPixel(i, j).ToArgb();
if (rgb < 0)
{
Color oriImageColor = baseImage.GetPixel(x + i, y + j);
//抠图区域半透明
baseImage.SetPixel(x + i, y + j, Color.FromArgb(120, oriImageColor.R, oriImageColor.G, oriImageColor.B));
}
//防止数组越界判断
if (i == (xLength - 1) || j == (yLength - 1))
{
continue;
}
int rightRgb = templateImage.GetPixel(i + 1, j).ToArgb();
int downRgb = templateImage.GetPixel(i, j + 1).ToArgb();
//描边处理,,取带像素和无像素的界点,判断该点是不是临界轮廓点,如果是设置该坐标像素是白色
if ((rgb >= 0 && rightRgb < 0) || (rgb < 0 && rightRgb >= 0) || (rgb >= 0 && downRgb < 0) || (rgb < 0 && downRgb >= 0))
{
baseImage.SetPixel(x + i, y + j, Color.White);
}
}
}
}
///
/// 更改图片尺寸
///
///
///
///
///
private Bitmap ResizeImage(Bitmap bmp, int width, int height)
{
try
{
Bitmap b = new Bitmap(width, height);
Graphics g = Graphics.FromImage(b);
// 图画质量
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
g.DrawImage(bmp, new Rectangle(0, 0, width, height), new Rectangle(0, 0, bmp.Width, bmp.Height), GraphicsUnit.Pixel);
g.Dispose();
return b;
}
catch
{
return null;
}
}
///
/// 随机范围内数字
///
///
///
///
public int GetRandomInt(int startNum, int endNum)
{
return (endNum > startNum ? new Random().Next(endNum - startNum) : 0) + startNum;
}
///
/// 随机生成拼图坐标
///
///
///
///
///
///
private PointModel GeneratePoint(int originalWidth, int originalHeight, int templateWidth, int templateHeight)
{
Random random = new Random();
int widthDifference = originalWidth - templateWidth;
int heightDifference = originalHeight - templateHeight;
int x;
if (widthDifference <= 0)
{
x = 5;
}
else
{
x = random.Next(originalWidth - templateWidth - 100) + 100;
}
int y;
if (heightDifference <= 0)
{
y = 5;
}
else
{
y = random.Next(originalHeight - templateHeight - 5) + 5;
}
return new PointModel(x, y);
}
///
/// 随机生成干扰图坐标
///
///
///
///
///
///
///
///
private PointModel GenerateInterferencePoint(int originalWidth, int originalHeight, int templateWidth, int templateHeight, int blockX, int blockY)
{
int x;
if (originalWidth - blockX - 5 > templateWidth * 2)
{
//在原扣图右边插入干扰图
x = GetRandomInt(blockX + templateWidth + 5, originalWidth - templateWidth);
}
else
{
//在原扣图左边插入干扰图
x = GetRandomInt(100, blockX - templateWidth - 5);
}
int y;
if (originalHeight - blockY - 5 > templateHeight * 2)
{
//在原扣图下边插入干扰图
y = GetRandomInt(blockY + templateHeight + 5, originalHeight - templateHeight);
}
else
{
//在原扣图上边插入干扰图
y = GetRandomInt(5, blockY - templateHeight - 5);
}
return new PointModel(x, y);
}
///
/// 获得验证数据
///
/// JObject
public async Task GetAsync()
{
//获取网络图片
//var client = new HttpClient();
//var stream = await client.GetStreamAsync("https://picsum.photos/310/155");
//client.Dispose();
//更改图片尺寸
//Bitmap oriImage = new Bitmap(stream);
//Bitmap baseImage = ResizeImage(oriImage, 310, 155);
//oriImage.Dispose();
//Bitmap baseImage = new Bitmap(stream);
var oriImage = Image.FromFile(Directory.GetCurrentDirectory() + $@"\wwwroot\captcha\jigsaw\{new Random().Next(1, 4)}.jpg");
Bitmap baseImage = new Bitmap(oriImage);
oriImage.Dispose();
var oriTemplate = Image.FromFile(Directory.GetCurrentDirectory() + $@"\wwwroot\captcha\jigsaw\templates\{new Random().Next(1, 7)}.png");
Bitmap templateImage = new Bitmap(oriTemplate);
oriTemplate.Dispose();
int baseWidth = baseImage.Width;
int baseHeight = baseImage.Height;
int templateWidth = templateImage.Width;
int templateHeight = templateImage.Height;
//随机生成拼图坐标
PointModel point = GeneratePoint(baseWidth, baseHeight, templateWidth, templateHeight);
int x = point.X;
int y = point.Y;
//生成拼图
string blockImageBase64 = "data:image/png;base64," + ImgToBase64String(CutByTemplate(baseImage, templateImage, x, y));
//生成干扰图
PointModel interferencePoint = GenerateInterferencePoint(baseWidth, baseHeight, templateWidth, templateHeight, x, y);
InterferenceByTemplate(baseImage, templateImage, interferencePoint.X, interferencePoint.Y);
string baseImageBase64 = "data:image/png;base64," + ImgToBase64String(baseImage);
templateImage.Dispose();
baseImage.Dispose();
var token = Guid.NewGuid().ToString();
CaptchaOutput captchaData = new CaptchaOutput
{
Token = token,
Data = new SlideJigsawCaptchaModel()
{
BlockImage = blockImageBase64,
BaseImage = baseImageBase64
}
};
var key = string.Format(CacheKey.VerifyCodeKey, token);
await _cache.SetAsync(key, point.X);
return captchaData;
}
///
/// 检查验证数据
///
public async Task CheckAsync(SlideJigsawCaptchaInput input)
{
var key = string.Format(CacheKey.VerifyCodeKey, input.Token);
if (await _cache.ExistsAsync(key))
{
try
{
var point = JsonConvert.DeserializeObject(input.Point);
var x = await _cache.GetAsync(key);
if (Math.Abs(x - point.X) < 5)
{
return true;
}
else
{
return false;
}
}
catch
{
await _cache.DelAsync(key);
return false;
}
}
else
{
return false;
}
}
}
}