content: /*
   * Copyright 2007 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.Config;
  import com.ailiwean.core.zxing.core.BarcodeFormat;
  import com.ailiwean.core.zxing.core.BinaryBitmap;
  import com.ailiwean.core.zxing.core.ChecksumException;
  import com.ailiwean.core.zxing.core.DecodeHintType;
  import com.ailiwean.core.zxing.core.FormatException;
  import com.ailiwean.core.zxing.core.NotFoundException;
  import com.ailiwean.core.zxing.core.Reader;
  import com.ailiwean.core.zxing.core.Result;
  import com.ailiwean.core.zxing.core.ResultMetadataType;
  import com.ailiwean.core.zxing.core.ResultPoint;
  import com.ailiwean.core.zxing.core.common.BitMatrix;
  import com.ailiwean.core.zxing.core.common.DecoderResult;
  import com.ailiwean.core.zxing.core.common.DetectorResult;
  import com.ailiwean.core.zxing.core.qrcode.decoder.Decoder;
  import com.ailiwean.core.zxing.core.qrcode.decoder.QRCodeDecoderMetaData;
  import com.ailiwean.core.zxing.core.qrcode.detector.Detector;
  import com.ailiwean.core.zxing.core.qrcode.detector.Detector2;
  
  import java.util.List;
  import java.util.Map;
  
  /**
   * This implementation can detect and decode QR Codes in an image.
   *
   * @author Sean Owen
   */
  public class QRCodeReader implements Reader {
  
      private static final ResultPoint[] NO_POINTS = new ResultPoint[0];
  
      private final Decoder decoder = new Decoder();
  
      protected final Decoder getDecoder() {
          return decoder;
      }
  
      /**
       * Locates and decodes a QR code in an image.
       *
       * @return a String representing the content encoded by the QR code
       * @throws NotFoundException if a QR code cannot be found
       * @throws FormatException   if a QR code cannot be decoded
       * @throws ChecksumException if error correction fails
       */
      @Override
      public Result decode(BinaryBitmap image) throws NotFoundException, ChecksumException, FormatException {
          return decode(image, null);
      }
  
      @Override
      public final Result decode(BinaryBitmap image, Map<DecodeHintType, ?> hints)
              throws ChecksumException, FormatException, NotFoundException {
          DecoderResult decoderResult;
          ResultPoint[] points;
          if (hints != null && hints.containsKey(DecodeHintType.PURE_BARCODE)) {
              BitMatrix bits;
              try {
                  bits = extractPureBits(image.getBlackMatrix());
              } catch (NotFoundException e) {
                  return null;
              }
              decoderResult = decoder.decode(bits, hints);
              points = NO_POINTS;
          } else {
              DetectorResult detectorResult;
              try {
                  detectorResult = new Detector(image.getBlackMatrix()).detect(hints);
              } catch (NotFoundException e) {
                  if (Config.isSupportBlackEdge) {
                      try {
                          detectorResult = new Detector2(image.getBlackMatrix()).detect(hints);
                      } catch (NotFoundException notFoundException) {
                          throw NotFoundException.getNotFoundInstance();
                      }
                  } else
                      throw NotFoundException.getNotFoundInstance();
              }
              points = detectorResult.getPoints();
              try {
                  decoderResult = decoder.decode(detectorResult.getBits(), hints);
              } catch (Exception ignored) {
                  return new Result(null, null, points, null);
              }
          }
          // If the code was mirrored: swap the bottom-left and the top-right points.
          if (decoderResult.getOther() instanceof QRCodeDecoderMetaData) {
              ((QRCodeDecoderMetaData) decoderResult.getOther()).applyMirroredCorrection(points);
          }
  
          Result result = new Result(decoderResult.getText(), decoderResult.getRawBytes(), points, BarcodeFormat.QR_CODE);
          List<byte[]> byteSegments = decoderResult.getByteSegments();
          if (byteSegments != null) {
              result.putMetadata(ResultMetadataType.BYTE_SEGMENTS, byteSegments);
          }
          String ecLevel = decoderResult.getECLevel();
          if (ecLevel != null) {
              result.putMetadata(ResultMetadataType.ERROR_CORRECTION_LEVEL, ecLevel);
          }
          if (decoderResult.hasStructuredAppend()) {
              result.putMetadata(ResultMetadataType.STRUCTURED_APPEND_SEQUENCE,
                      decoderResult.getStructuredAppendSequenceNumber());
              result.putMetadata(ResultMetadataType.STRUCTURED_APPEND_PARITY,
                      decoderResult.getStructuredAppendParity());
          }
          return result;
      }
  
      @Override
      public void reset() {
          // do nothing
      }
  
      /**
       * This method detects a code in a "pure" image -- that is, pure monochrome image
       * which contains only an unrotated, unskewed, image of a code, with some white border
       * around it. This is a specialized method that works exceptionally fast in this special
       * case.
       */
      private static BitMatrix extractPureBits(BitMatrix image) throws NotFoundException {
  
          int[] leftTopBlack = image.getTopLeftOnBit();
          int[] rightBottomBlack = image.getBottomRightOnBit();
          if (leftTopBlack == null || rightBottomBlack == null) {
              throw NotFoundException.getNotFoundInstance();
          }
  
          float moduleSize = moduleSize(leftTopBlack, image);
  
          int top = leftTopBlack[1];
          int bottom = rightBottomBlack[1];
          int left = leftTopBlack[0];
          int right = rightBottomBlack[0];
  
          // Sanity check!
          if (left >= right || top >= bottom) {
              throw NotFoundException.getNotFoundInstance();
          }
  
          if (bottom - top != right - left) {
              // Special case, where bottom-right module wasn't black so we found something else in the last row
              // Assume it's a square, so use height as the width
              right = left + (bottom - top);
              if (right >= image.getWidth()) {
                  // Abort if that would not make sense -- off image
                  throw NotFoundException.getNotFoundInstance();
              }
          }
  
          int matrixWidth = Math.round((right - left + 1) / moduleSize);
          int matrixHeight = Math.round((bottom - top + 1) / moduleSize);
          if (matrixWidth <= 0 || matrixHeight <= 0) {
              throw NotFoundException.getNotFoundInstance();
          }
          if (matrixHeight != matrixWidth) {
              // Only possibly decode square regions
              throw NotFoundException.getNotFoundInstance();
          }
  
          // Push in the "border" by half the module width so that we start
          // sampling in the middle of the module. Just in case the image is a
          // little off, this will help recover.
          int nudge = (int) (moduleSize / 2.0f);
          top += nudge;
          left += nudge;
  
          // But careful that this does not sample off the edge
          // "right" is the farthest-right valid pixel location -- right+1 is not necessarily
          // This is positive by how much the inner x loop below would be too large
          int nudgedTooFarRight = left + (int) ((matrixWidth - 1) * moduleSize) - right;
          if (nudgedTooFarRight > 0) {
              if (nudgedTooFarRight > nudge) {
                  // Neither way fits; abort
                  throw NotFoundException.getNotFoundInstance();
              }
              left -= nudgedTooFarRight;
          }
          // See logic above
          int nudgedTooFarDown = top + (int) ((matrixHeight - 1) * moduleSize) - bottom;
          if (nudgedTooFarDown > 0) {
              if (nudgedTooFarDown > nudge) {
                  // Neither way fits; abort
                  throw NotFoundException.getNotFoundInstance();
              }
              top -= nudgedTooFarDown;
          }
  
          // Now just read off the bits
          BitMatrix bits = new BitMatrix(matrixWidth, matrixHeight);
          for (int y = 0; y < matrixHeight; y++) {
              int iOffset = top + (int) (y * moduleSize);
              for (int x = 0; x < matrixWidth; x++) {
                  if (image.get(left + (int) (x * moduleSize), iOffset)) {
                      bits.set(x, y);
                  }
              }
          }
          return bits;
      }
  
      private static float moduleSize(int[] leftTopBlack, BitMatrix image) throws
              NotFoundException {
          int height = image.getHeight();
          int width = image.getWidth();
          int x = leftTopBlack[0];
          int y = leftTopBlack[1];
          boolean inBlack = true;
          int transitions = 0;
          while (x < width && y < height) {
              if (inBlack != image.get(x, y)) {
                  if (++transitions == 5) {
                      break;
                  }
                  inBlack = !inBlack;
              }
              x++;
              y++;
          }
          if (x == width || y == height) {
              throw NotFoundException.getNotFoundInstance();
          }
          return (x - leftTopBlack[0]) / 7.0f;
      }
  
  }
  