package com.hmw.picMark;

import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.geom.AffineTransform;
import java.awt.image.AffineTransformOp;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;

/**
 * 图片工具类， 图片水印，文字水印，缩放，补白等
 * @author Carl He
 */
public final class ImageUtils {
 /**图片格式：JPG*/
 private static final String PICTRUE_FORMATE_JPG = "jpg";
 
 private ImageUtils(){}
 /**
  * 添加图片水印
  * @param targetImg 目标图片路径，如：C://myPictrue//1.jpg
  * @param waterImg 水印图片路径，如：C://myPictrue//logo.png
  * @param x 水印图片距离目标图片左侧的偏移量，如果x<0, 则在正中间
  * @param y 水印图片距离目标图片上侧的偏移量，如果y<0, 则在正中间
  * @param alpha 透明度(0.0 -- 1.0, 0.0为完全透明，1.0为完全不透明)
  */
 public final static void pressImage(String targetImg, String waterImg, int x, int y, float alpha) {
   try {
    File file = new File(targetImg);
    Image image = ImageIO.read(file);
    int width = image.getWidth(null);
    int height = image.getHeight(null);
    BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
    Graphics2D g = bufferedImage.createGraphics();
    g.drawImage(image, 0, 0, width, height, null);
   
    Image waterImage = ImageIO.read(new File(waterImg)); // 水印文件
    int width_1 = waterImage.getWidth(null);
    int height_1 = waterImage.getHeight(null);
    g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, alpha));
    
    int widthDiff = width - width_1;
    int heightDiff = height - height_1;
    if(x < 0){
     x = widthDiff / 2;
    }else if(x > widthDiff){
     x = widthDiff;
    }
    if(y < 0){
     y = heightDiff / 2;
    }else if(y > heightDiff){
     y = heightDiff;
    }
    g.drawImage(waterImage, x, y, width_1, height_1, null); // 水印文件结束
    g.dispose();
    ImageIO.write(bufferedImage, PICTRUE_FORMATE_JPG, file);
   } catch (IOException e) {
    e.printStackTrace();
   }
 }

 /**
  * 添加文字水印
  * @param targetImg 目标图片路径，如：C://myPictrue//1.jpg
  * @param pressText 水印文字， 如：中国证券网
  * @param fontName 字体名称， 如：宋体
  * @param fontStyle 字体样式，如：粗体和斜体(Font.BOLD|Font.ITALIC)
  * @param fontSize 字体大小，单位为像素
  * @param color 字体颜色
  * @param x 水印文字距离目标图片左侧的偏移量，如果x<0, 则在正中间
  * @param y 水印文字距离目标图片上侧的偏移量，如果y<0, 则在正中间
  * @param alpha 透明度(0.0 -- 1.0, 0.0为完全透明，1.0为完全不透明)
  */
 public static void pressText(String targetImg, String pressText, String fontName, int fontStyle, int fontSize, Color color, int x, int y, float alpha) {
  try {
   File file = new File(targetImg);
   
   Image image = ImageIO.read(file);
   int width = image.getWidth(null);
   int height = image.getHeight(null);
   BufferedImage bufferedImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
   Graphics2D g = bufferedImage.createGraphics();
   g.drawImage(image, 0, 0, width, height, null);
   g.setFont(new Font(fontName, fontStyle, fontSize));
   g.setColor(color);
   g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, alpha));
   
   int width_1 = fontSize * getLength(pressText);
   int height_1 = fontSize;
   int widthDiff = width - width_1;
   int heightDiff = height - height_1;
   if(x < 0){
    x = widthDiff / 2;
   }else if(x > widthDiff){
    x = widthDiff;
   }
   if(y < 0){
    y = heightDiff / 2;
   }else if(y > heightDiff){
    y = heightDiff;
   }
   
   g.drawString(pressText, x, y + height_1);
   g.dispose();
   ImageIO.write(bufferedImage, PICTRUE_FORMATE_JPG, file);
  } catch (Exception e) {
   e.printStackTrace();
  }
 }
 
 /**
  * 获取字符长度，一个汉字作为 1 个字符, 一个英文字母作为 0.5 个字符
  * @param text
  * @return 字符长度，如：text="中国",返回 2；text="test",返回 2；text="中国ABC",返回 4.
  */
 public static int getLength(String text) {
  int textLength = text.length();
  int length = textLength;
  for (int i = 0; i < textLength; i++) {
   if (String.valueOf(text.charAt(i)).getBytes().length > 1) {
    length++;
   }
  }
  return (length % 2 == 0) ? length / 2 : length / 2 + 1;
 }

 /**
  * 图片缩放
  * @param filePath 图片路径
  * @param height 高度
  * @param width 宽度
  * @param bb 比例不对时是否需要补白
  */
 public static void resize(String filePath, int height, int width, boolean bb) {
  try {
   double ratio = 0; //缩放比例  
      File f = new File(filePath);  
      BufferedImage bi = ImageIO.read(f);  
      Image itemp = bi.getScaledInstance(width, height, BufferedImage.SCALE_SMOOTH);  
      //计算比例  
      if ((bi.getHeight() > height) || (bi.getWidth() > width)) {  
        if (bi.getHeight() > bi.getWidth()) {  
          ratio = (new Integer(height)).doubleValue() / bi.getHeight();  
        } else {  
          ratio = (new Integer(width)).doubleValue() / bi.getWidth();  
        }  
        AffineTransformOp op = new AffineTransformOp(AffineTransform.getScaleInstance(ratio, ratio), null);  
        itemp = op.filter(bi, null);  
      }  
      if (bb) {  
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);  
        Graphics2D g = image.createGraphics();  
        g.setColor(Color.white);  
        g.fillRect(0, 0, width, height);  
        if (width == itemp.getWidth(null))  
          g.drawImage(itemp, 0, (height - itemp.getHeight(null)) / 2, itemp.getWidth(null), itemp.getHeight(null), Color.white, null);  
        else 
          g.drawImage(itemp, (width - itemp.getWidth(null)) / 2, 0, itemp.getWidth(null), itemp.getHeight(null), Color.white, null);  
        g.dispose();  
        itemp = image;  
      }
      ImageIO.write((BufferedImage) itemp, "jpg", f);  
  } catch (IOException e) {
   e.printStackTrace();
  }
 }

 public static void main(String[] args) throws IOException {
  pressImage("C://pic//jpg", "C://pic//test.gif", 5000, 5000, 0f);
  pressText("C://pic//jpg", "旺仔之印", "宋体", Font.BOLD|Font.ITALIC, 20, Color.BLACK, 0, 0, 8f);
  resize("C://pic//4.jpg", 1000, 500, true);
 }
}