content: /*
   * Copyright 2019 ACINQ SAS
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package fr.acinq.eclair.wallet.tasks;
  
  import android.graphics.Bitmap;
  import android.graphics.Color;
  import android.os.AsyncTask;
  
  import com.google.zxing.BarcodeFormat;
  import com.google.zxing.EncodeHintType;
  import com.google.zxing.WriterException;
  import com.google.zxing.common.BitMatrix;
  import com.google.zxing.qrcode.QRCodeWriter;
  import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
  
  import com.google.zxing.qrcode.encoder.Encoder;
  import com.google.zxing.qrcode.encoder.QRCode;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.util.HashMap;
  import java.util.Map;
  
  
  public class QRCodeTask extends AsyncTask<String, Integer, Bitmap> {
  
    private final Logger log = LoggerFactory.getLogger(QRCodeTask.class);
  
    public interface AsyncQRCodeResponse {
      void processFinish(Bitmap output);
    }
  
    private AsyncQRCodeResponse delegate;
  
    private final int width;
    private final int height;
    private final String source;
  
    public QRCodeTask(AsyncQRCodeResponse delegate, String source, int width, int height) {
      this.delegate = delegate;
      this.width = width;
      this.height = height;
      this.source = "bitcoin:" + source;
    }
  
    @Override
    protected Bitmap doInBackground(String... params) {
      try {
        return generateBitmap(this.source, this.width, this.height);
      } catch (Exception e) {
        log.warn("failed to generate QR code image for address {} with cause {}", source, e.getMessage());
        return null;
      }
    }
  
    protected void onPostExecute(Bitmap result) {
      delegate.processFinish(result);
    }
  
    static Bitmap generateBitmap(final String source, final int finalWidth, final int finalHeight) throws WriterException {
      final Map<EncodeHintType, Object> hintsMap = new HashMap<>();
      hintsMap.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.L);
      hintsMap.put(EncodeHintType.MARGIN, 0);
      QRCode qrCode = Encoder.encode(source, ErrorCorrectionLevel.L, hintsMap);
      int width = qrCode.getMatrix().getWidth();
      int height = qrCode.getMatrix().getHeight();
      int[] rgbArray = new int[width * height];
      int i = 0;
      for (int y = 0; y < height; y++) {
        for (int x = 0; x < width; x++) {
          rgbArray[i] = qrCode.getMatrix().get(x, y) > 0 ? Color.BLACK : Color.WHITE;
          i++;
        }
      }
      return Bitmap.createScaledBitmap(Bitmap.createBitmap(rgbArray, width, height, Bitmap.Config.RGB_565), finalWidth, finalHeight, false);
    }
  }
  