import android.graphics.Bitmap;

 import android.graphics.Canvas;

 import android.graphics.Color;

 import android.graphics.Paint;

 import java.util.Random;

 /**

  * Created by ekikousei易皇星 on 16/11/21.

  * E-mail:13764664731@163.com

  * Signature:缘分是本书,翻的不经意会错过,读的太认真会流泪!!

  * <p/>

  * TODO:类描述:  用于图形验证码的工具类

  */

 public class CodeUtils {

 //    private static final char[] CHARS = {

 //            '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',

 //            'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',

 //            'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',

 //            'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',

 //            'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'

 //    };

     private static final char[] CHARS = {

             'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',

             'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',

     };

     private static CodeUtils mCodeUtils;

     private int mPaddingLeft, mPaddingTop;

     private StringBuilder mBuilder = new StringBuilder();

     private Random mRandom = new Random();

     //Default Settings

 //    private static final int DEFAULT_CODE_LENGTH = 6;//验证码的长度  这里是6位

     private static final int DEFAULT_CODE_LENGTH = 4;//验证码的长度  这里是4位

     private static final int DEFAULT_FONT_SIZE = 60;//字体大小

     private static final int DEFAULT_LINE_NUMBER = 3;//多少条干扰线

     private static final int BASE_PADDING_LEFT = 40; //左边距

     private static final int RANGE_PADDING_LEFT = 30;//左边距范围值

     private static final int BASE_PADDING_TOP = 70;//上边距

     private static final int RANGE_PADDING_TOP = 15;//上边距范围值

     private static final int DEFAULT_WIDTH = 300;//默认宽度.图片的总宽

     private static final int DEFAULT_HEIGHT = 100;//默认高度.图片的总高

     private static final int DEFAULT_COLOR = 0xDF;//默认背景颜色值

     private String code;

     public static CodeUtils getInstance() {

         if (mCodeUtils == null) {

             mCodeUtils = new CodeUtils();

         }

         return mCodeUtils;

     }

     //生成验证码图片  返回类型为bitmap 直接用imageview.setbitmap()即可

     public Bitmap createBitmap() {

         mPaddingLeft = 0; //每次生成验证码图片时初始化

         mPaddingTop = 0;

         Bitmap bitmap = Bitmap.createBitmap(DEFAULT_WIDTH, DEFAULT_HEIGHT, Bitmap.Config.ARGB_8888);

         Canvas canvas = new Canvas(bitmap);

         code = createCode();

         canvas.drawColor(Color.rgb(DEFAULT_COLOR, DEFAULT_COLOR, DEFAULT_COLOR));

         Paint paint = new Paint();

         paint.setTextSize(DEFAULT_FONT_SIZE);

         for (int i = 0; i < code.length(); i++) {

             randomTextStyle(paint);

             randomPadding();

             canvas.drawText(code.charAt(i) + "", mPaddingLeft, mPaddingTop, paint);

         }

         //干扰线

         for (int i = 0; i < DEFAULT_LINE_NUMBER; i++) {

             drawLine(canvas, paint);

         }

         canvas.save(Canvas.ALL_SAVE_FLAG);//保存

         canvas.restore();

         return bitmap;

     }

     /**

      * 得到图片中的验证码字符串

      *

      * @return

      */

     public String getCode() {

         return code;

     }

     //生成验证码

     public String createCode() {

         mBuilder.delete(0, mBuilder.length()); //使用之前首先清空内容

         for (int i = 0; i < DEFAULT_CODE_LENGTH; i++) {

             mBuilder.append(CHARS[mRandom.nextInt(CHARS.length)]);

         }

         return mBuilder.toString();

     }

     //生成干扰线

     private void drawLine(Canvas canvas, Paint paint) {

         int color = randomColor();

         int startX = mRandom.nextInt(DEFAULT_WIDTH);

         int startY = mRandom.nextInt(DEFAULT_HEIGHT);

         int stopX = mRandom.nextInt(DEFAULT_WIDTH);

         int stopY = mRandom.nextInt(DEFAULT_HEIGHT);

         paint.setStrokeWidth(1);

         paint.setColor(color);

         canvas.drawLine(startX, startY, stopX, stopY, paint);

     }

     //随机颜色

     private int randomColor() {

         mBuilder.delete(0, mBuilder.length()); //使用之前首先清空内容

         String haxString;

         for (int i = 0; i < 3; i++) {

             haxString = Integer.toHexString(mRandom.nextInt(0xFF));

             if (haxString.length() == 1) {

                 haxString = "0" + haxString;

             }

             mBuilder.append(haxString);

         }

         return Color.parseColor("#" + mBuilder.toString());

     }

     //随机文本样式

     private void randomTextStyle(Paint paint) {

         int color = randomColor();

         paint.setColor(color);

         paint.setFakeBoldText(mRandom.nextBoolean());  //true为粗体，false为非粗体

         float skewX = mRandom.nextInt(11) / 10;

         skewX = mRandom.nextBoolean() ? skewX : -skewX;

         paint.setTextSkewX(skewX); //float类型参数，负数表示右斜，整数左斜

 //        paint.setUnderlineText(true); //true为下划线，false为非下划线

 //        paint.setStrikeThruText(true); //true为删除线，false为非删除线

     }

     //随机间距

     private void randomPadding() {

         mPaddingLeft += BASE_PADDING_LEFT + mRandom.nextInt(RANGE_PADDING_LEFT);

         mPaddingTop = BASE_PADDING_TOP + mRandom.nextInt(RANGE_PADDING_TOP);

     }

 }