package com.shunzhi.mychartlibrary.utils;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.media.ExifInterface;

public class PictureUtil {

	/**
	 * 计算图片的缩放值
	 * 
	 * @param options
	 * @param reqWidth
	 * @param reqHeight
	 * @return
	 */
	public static int calculateInSampleSize(BitmapFactory.Options options,
			int reqWidth, int reqHeight) {
		// Raw height and width of image
		final int height = options.outHeight;
		final int width = options.outWidth;
		int inSampleSize = 1;

		if (height > reqHeight || width > reqWidth) {

			// Calculate ratios of height and width to requested height and
			// width
			final int heightRatio = Math.round((float) height
					/ (float) reqHeight);
			final int widthRatio = Math.round((float) width / (float) reqWidth);

			// Choose the smallest ratio as inSampleSize value, this will
			// guarantee
			// a final image with both dimensions larger than or equal to the
			// requested height and width.
			inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
		}

		return inSampleSize;
	}

	/**
	 * 根据路径获得图片并压缩返回bitmap用于显示
	 * 
	 * @param imagesrc
	 * @return
	 */
	public static Bitmap getSmallBitmap(String filePath) {
		final BitmapFactory.Options options = new BitmapFactory.Options();
		options.inJustDecodeBounds = true;
		BitmapFactory.decodeFile(filePath, options);

		// Calculate inSampleSize
		options.inSampleSize = calculateInSampleSize(options, 320, 480);

		// Decode bitmap with inSampleSize set
		options.inJustDecodeBounds = false;

		return BitmapFactory.decodeFile(filePath, options);
	}
	
	/**
	 * 压缩大图片
	 * @param srcPath
	 * @return
	 */
	public static Bitmap compressSizeImage(String srcPath) {  
        BitmapFactory.Options newOpts = new BitmapFactory.Options();  
        //开始读入图片，此时把options.inJustDecodeBounds 设回true了  
        newOpts.inJustDecodeBounds = true;  
        Bitmap bitmap = BitmapFactory.decodeFile(srcPath,newOpts);//此时返回bm为空  
          
        newOpts.inJustDecodeBounds = false;  
        int w = newOpts.outWidth;  
        int h = newOpts.outHeight;  
        //现在主流手机比较多是800*480分辨率，所以高和宽我们设置为  
        float hh = 800f;//这里设置高度为800f  
        float ww = 480f;//这里设置宽度为480f  
        //缩放比。由于是固定比例缩放，只用高或者宽其中一个数据进行计算即可  
        int be = 1;//be=1表示不缩放  
        if (w > h && w > ww) {//如果宽度大的话根据宽度固定大小缩放  
            be = (int) (newOpts.outWidth / ww);  
        } else if (w < h && h > hh) {//如果高度高的话根据宽度固定大小缩放  
            be = (int) (newOpts.outHeight / hh);  
        }  
        if (be <= 0)  
            be = 1;  
        newOpts.inSampleSize = be;//设置缩放比例  
        //重新读入图片，注意此时已经把options.inJustDecodeBounds 设回false了  
        bitmap = BitmapFactory.decodeFile(srcPath, newOpts);  
        return compressImage(bitmap);//压缩好比例大小后再进行质量压缩  
    }  
	
	public static Bitmap compressImage(Bitmap image) {  
		  
        ByteArrayOutputStream baos = new ByteArrayOutputStream();  
        image.compress(Bitmap.CompressFormat.JPEG, 100, baos);//质量压缩方法，这里100表示不压缩，把压缩后的数据存放到baos中  
        int options = 100;  
        while ( baos.toByteArray().length / 1024>100) {  //循环判断如果压缩后图片是否大于100kb,大于继续压缩         
            baos.reset();//重置baos即清空baos  
            image.compress(Bitmap.CompressFormat.JPEG, options, baos);//这里压缩options%，把压缩后的数据存放到baos中  
            options -= 10;//每次都减少10  
        }  
        ByteArrayInputStream isBm = new ByteArrayInputStream(baos.toByteArray());//把压缩后的数据baos存放到ByteArrayInputStream中  
        Bitmap bitmap = BitmapFactory.decodeStream(isBm, null, null);//把ByteArrayInputStream数据生成图片  
        return bitmap;  
    }  
	
	 /** 
	 * 获取图片文件的信息，是否旋转了90度，如果是则反转 
	 * @param bitmap 需要旋转的图片 
	 * @param path   图片的路径 
	 */  
	public static Bitmap reviewPicRotate(Bitmap bitmap,String path){  
	    int degree = getPicRotate(path);  
	    if(degree!=0){  
	        Matrix m = new Matrix();    
	        int width = bitmap.getWidth();    
	        int height = bitmap.getHeight();    
	        m.setRotate(degree); // 旋转angle度    
	        bitmap = Bitmap.createBitmap(bitmap, 0, 0, width, height,m, true);// 从新生成图片    
	    }  
	    return bitmap;  
	}  
	  
	/** 
	 * 读取图片文件旋转的角度 
	 * @param path 图片绝对路径 
	 * @return 图片旋转的角度 
	 */  
	public static int getPicRotate(String path) {  
	    int degree  = 0;  
	    try {  
	        ExifInterface exifInterface = new ExifInterface(path);  
	        int orientation = exifInterface.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL);  
	        switch (orientation) {  
	        case ExifInterface.ORIENTATION_ROTATE_90:  
	            degree = 90;  
	            break;  
	        case ExifInterface.ORIENTATION_ROTATE_180:  
	            degree = 180;  
	            break;  
	        case ExifInterface.ORIENTATION_ROTATE_270:  
	            degree = 270;  
	            break;  
	        }  
	    } catch (IOException e) {  
	        e.printStackTrace();  
	    }  
	    return degree;  
	}  
}