package com.example.administrator.twocodedemo;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.PointF;
import android.view.Gravity;
import android.view.View.MeasureSpec;
import android.widget.LinearLayout;
import android.widget.LinearLayout.LayoutParams;
import android.widget.TextView;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.QRCodeWriter;

import java.util.Hashtable;

/** 
*
* 	生成條形碼和二維碼的工具
*/
public class ZXingUtils {
	/**
	 * 生成二維碼 要轉換的地址或字串,可以是中文
	 * 
	 * @param url
	 * @param width
	 * @param height
	 * @return
	 */
	public static Bitmap createQRImage(String url, final int width, final int height) {
		try {
			// 判斷URL合法性
			if (url == null || "".equals(url) || url.length() < 1) {
				return null;
			}
			Hashtable hints = new Hashtable();
			hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
			// 影象資料轉換，使用了矩陣轉換
			BitMatrix bitMatrix = new QRCodeWriter().encode(url,
					BarcodeFormat.QR_CODE, width, height, hints);
			int[] pixels = new int[width * height];
			// 下面這裡按照二維碼的演算法，逐個生成二維碼的圖片，
			// 兩個for迴圈是圖片橫列掃描的結果
			for (int y = 0; y < height; y++) {
				for (int x = 0; x < width; x++) {
					if (bitMatrix.get(x, y)) {
						pixels[y * width + x] = 0xff000000;
					} else {
						pixels[y * width + x] = 0xffffffff;
					}
				}
			}
			// 生成二維碼圖片的格式，使用ARGB_8888
			Bitmap bitmap = Bitmap.createBitmap(width, height,
					Bitmap.Config.ARGB_8888);
			bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
			return bitmap;
		} catch (WriterException e) {
			e.printStackTrace();
		}
		return null;
	}

	/**
	 * 生成條形碼
	 *
	 * @param context
	 * @param contents
	 *            需要生成的內容
	 * @param desiredWidth
	 *            生成條形碼的寬頻
	 * @param desiredHeight
	 *            生成條形碼的高度
	 * @param displayCode
	 *            是否在條形碼下方顯示內容
	 * @return
	 */
	public static Bitmap creatBarcode(Context context, String contents,
									  int desiredWidth, int desiredHeight, boolean displayCode) {
		Bitmap ruseltBitmap = null;
		/**
		 * 圖片兩端所保留的空白的寬度
		 */
		int marginW = 20;
		/**
		 * 條形碼的編碼型別
		 */
		BarcodeFormat barcodeFormat = BarcodeFormat.CODE_128;

		if (displayCode) {
			Bitmap barcodeBitmap = encodeAsBitmap(contents, barcodeFormat,
					desiredWidth, desiredHeight);
			Bitmap codeBitmap = creatCodeBitmap(contents, desiredWidth + 2
					* marginW, desiredHeight, context);
			ruseltBitmap = mixtureBitmap(barcodeBitmap, codeBitmap, new PointF(
					0, desiredHeight));
		} else {
			ruseltBitmap = encodeAsBitmap(contents, barcodeFormat,
					desiredWidth, desiredHeight);
		}

		return ruseltBitmap;
	}

	/**
	 * 生成條形碼的Bitmap
	 *
	 * @param contents
	 *            需要生成的內容
	 * @param format
	 *            編碼格式
	 * @param desiredWidth
	 * @param desiredHeight
	 * @return
	 * @throws WriterException
	 */
	protected static Bitmap encodeAsBitmap(String contents,
										   BarcodeFormat format, int desiredWidth, int desiredHeight) {
		final int WHITE = 0xFFFFFFFF;
		final int BLACK = 0xFF000000;

		MultiFormatWriter writer = new MultiFormatWriter();
		BitMatrix result = null;
		try {
			result = writer.encode(contents, format, desiredWidth,
					desiredHeight, null);
		} catch (WriterException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

		int width = result.getWidth();
		int height = result.getHeight();
		int[] pixels = new int[width * height];
		// All are 0, or black, by default
		for (int y = 0; y < height; y++) {
			int offset = y * width;
			for (int x = 0; x < width; x++) {
				pixels[offset + x] = result.get(x, y) ? BLACK : WHITE;
			}
		}

		Bitmap bitmap = Bitmap.createBitmap(width, height,
				Bitmap.Config.ARGB_8888);
		bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
		return bitmap;
	}

	/**
	 * 生成顯示編碼的Bitmap
	 *
	 * @param contents
	 * @param width
	 * @param height
	 * @param context
	 * @return
	 */
	protected static Bitmap creatCodeBitmap(String contents, int width,
											int height, Context context) {
		TextView tv = new TextView(context);
		LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
				LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
		tv.setLayoutParams(layoutParams);
		tv.setText(contents);
		tv.setHeight(height);
		tv.setGravity(Gravity.CENTER_HORIZONTAL);
		tv.setWidth(width);
		tv.setDrawingCacheEnabled(true);
		tv.setTextColor(Color.BLACK);
		tv.measure(MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED),
				MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
		tv.layout(0, 0, tv.getMeasuredWidth(), tv.getMeasuredHeight());

		tv.buildDrawingCache();
		Bitmap bitmapCode = tv.getDrawingCache();
		return bitmapCode;
	}

	/**
	 * 將兩個Bitmap合併成一個
	 * 
	 * @param first
	 * @param second
	 * @param fromPoint
	 *            第二個Bitmap開始繪製的起始位置（相對於第一個Bitmap）
	 * @return
	 */
	protected static Bitmap mixtureBitmap(Bitmap first, Bitmap second,
										  PointF fromPoint) {
		if (first == null || second == null || fromPoint == null) {
			return null;
		}
		int marginW = 20;
		Bitmap newBitmap = Bitmap.createBitmap(
				first.getWidth() + second.getWidth() + marginW,
				first.getHeight() + second.getHeight(), Config.ARGB_4444);
		Canvas cv = new Canvas(newBitmap);
		cv.drawBitmap(first, marginW, 0, null);
		cv.drawBitmap(second, fromPoint.x, fromPoint.y, null);
		cv.save(Canvas.ALL_SAVE_FLAG);
		cv.restore();

		return newBitmap;
	}

}