content: /*
   * Copyright 2008 ZXing authors
   *
   * 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 com.ailiwean.core.zxing.core.qrcode;
  
  import com.ailiwean.core.zxing.core.BarcodeFormat;
  import com.ailiwean.core.zxing.core.EncodeHintType;
  import com.ailiwean.core.zxing.core.Writer;
  import com.ailiwean.core.zxing.core.WriterException;
  import com.ailiwean.core.zxing.core.common.BitMatrix;
  import com.ailiwean.core.zxing.core.qrcode.decoder.ErrorCorrectionLevel;
  import com.ailiwean.core.zxing.core.qrcode.encoder.ByteMatrix;
  import com.ailiwean.core.zxing.core.qrcode.encoder.Encoder;
  import com.ailiwean.core.zxing.core.qrcode.encoder.QRCode;
  
  import java.util.Map;
  
  /**
   * This object renders a QR Code as a BitMatrix 2D array of greyscale values.
   *
   * @author dswitkin@google.com (Daniel Switkin)
   */
  public final class QRCodeWriter implements Writer {
  
    private static final int QUIET_ZONE_SIZE = 4;
  
    @Override
    public BitMatrix encode(String contents, BarcodeFormat format, int width, int height)
        throws WriterException {
  
      return encode(contents, format, width, height, null);
    }
  
    @Override
    public BitMatrix encode(String contents,
                            BarcodeFormat format,
                            int width,
                            int height,
                            Map<EncodeHintType,?> hints) throws WriterException {
  
      if (contents.isEmpty()) {
        throw new IllegalArgumentException("Found empty contents");
      }
  
      if (format != BarcodeFormat.QR_CODE) {
        throw new IllegalArgumentException("Can only encode QR_CODE, but got " + format);
      }
  
      if (width < 0 || height < 0) {
        throw new IllegalArgumentException("Requested dimensions are too small: " + width + 'x' +
            height);
      }
  
      ErrorCorrectionLevel errorCorrectionLevel = ErrorCorrectionLevel.L;
      int quietZone = QUIET_ZONE_SIZE;
      if (hints != null) {
        if (hints.containsKey(EncodeHintType.ERROR_CORRECTION)) {
          errorCorrectionLevel = ErrorCorrectionLevel.valueOf(hints.get(EncodeHintType.ERROR_CORRECTION).toString());
        }
        if (hints.containsKey(EncodeHintType.MARGIN)) {
          quietZone = Integer.parseInt(hints.get(EncodeHintType.MARGIN).toString());
        }
      }
  
      QRCode code = Encoder.encode(contents, errorCorrectionLevel, hints);
      return renderResult(code, width, height, quietZone);
    }
  
    // Note that the input matrix uses 0 == white, 1 == black, while the output matrix uses
    // 0 == black, 255 == white (i.e. an 8 bit greyscale bitmap).
    private static BitMatrix renderResult(QRCode code, int width, int height, int quietZone) {
      ByteMatrix input = code.getMatrix();
      if (input == null) {
        throw new IllegalStateException();
      }
      int inputWidth = input.getWidth();
      int inputHeight = input.getHeight();
      int qrWidth = inputWidth + (quietZone * 2);
      int qrHeight = inputHeight + (quietZone * 2);
      int outputWidth = Math.max(width, qrWidth);
      int outputHeight = Math.max(height, qrHeight);
  
      int multiple = Math.min(outputWidth / qrWidth, outputHeight / qrHeight);
      // Padding includes both the quiet zone and the extra white pixels to accommodate the requested
      // dimensions. For example, if input is 25x25 the QR will be 33x33 including the quiet zone.
      // If the requested size is 200x160, the multiple will be 4, for a QR of 132x132. These will
      // handle all the padding from 100x100 (the actual QR) up to 200x160.
      int leftPadding = (outputWidth - (inputWidth * multiple)) / 2;
      int topPadding = (outputHeight - (inputHeight * multiple)) / 2;
  
      BitMatrix output = new BitMatrix(outputWidth, outputHeight);
  
      for (int inputY = 0, outputY = topPadding; inputY < inputHeight; inputY++, outputY += multiple) {
        // Write the contents of this row of the barcode
        for (int inputX = 0, outputX = leftPadding; inputX < inputWidth; inputX++, outputX += multiple) {
          if (input.get(inputX, inputY) == 1) {
            output.setRegion(outputX, outputY, multiple, multiple);
          }
        }
      }
  
      return output;
    }
  
  }
  