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.oned;
  
  import com.ailiwean.core.zxing.core.BarcodeFormat;
  import com.ailiwean.core.zxing.core.DecodeHintType;
  import com.ailiwean.core.zxing.core.NotFoundException;
  import com.ailiwean.core.zxing.core.Reader;
  import com.ailiwean.core.zxing.core.ReaderException;
  import com.ailiwean.core.zxing.core.Result;
  import com.ailiwean.core.zxing.core.common.BitArray;
  
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Map;
  
  /**
   * <p>A reader that can read all available UPC/EAN formats. If a caller wants to try to
   * read all such formats, it is most efficient to use this implementation rather than invoke
   * individual readers.</p>
   *
   * @author Sean Owen
   */
  public final class MultiFormatUPCEANReader extends OneDReader {
  
    private static final UPCEANReader[] EMPTY_READER_ARRAY = new UPCEANReader[0];
  
    private final UPCEANReader[] readers;
  
    public MultiFormatUPCEANReader(Map<DecodeHintType,?> hints) {
      @SuppressWarnings("unchecked")
      Collection<BarcodeFormat> possibleFormats = hints == null ? null :
          (Collection<BarcodeFormat>) hints.get(DecodeHintType.POSSIBLE_FORMATS);
      Collection<UPCEANReader> readers = new ArrayList<>();
      if (possibleFormats != null) {
        if (possibleFormats.contains(BarcodeFormat.EAN_13)) {
          readers.add(new EAN13Reader());
        } else if (possibleFormats.contains(BarcodeFormat.UPC_A)) {
          readers.add(new UPCAReader());
        }
        if (possibleFormats.contains(BarcodeFormat.EAN_8)) {
          readers.add(new EAN8Reader());
        }
        if (possibleFormats.contains(BarcodeFormat.UPC_E)) {
          readers.add(new UPCEReader());
        }
      }
      if (readers.isEmpty()) {
        readers.add(new EAN13Reader());
        // UPC-A is covered by EAN-13
        readers.add(new EAN8Reader());
        readers.add(new UPCEReader());
      }
      this.readers = readers.toArray(EMPTY_READER_ARRAY);
    }
  
    @Override
    public Result decodeRow(int rowNumber,
                            BitArray row,
                            Map<DecodeHintType,?> hints) throws NotFoundException {
      // Compute this location once and reuse it on multiple implementations
      int[] startGuardPattern = UPCEANReader.findStartGuardPattern(row);
      for (UPCEANReader reader : readers) {
        try {
          Result result = reader.decodeRow(rowNumber, row, startGuardPattern, hints);
          // Special case: a 12-digit code encoded in UPC-A is identical to a "0"
          // followed by those 12 digits encoded as EAN-13. Each will recognize such a code,
          // UPC-A as a 12-digit string and EAN-13 as a 13-digit string starting with "0".
          // Individually these are correct and their readers will both read such a code
          // and correctly call it EAN-13, or UPC-A, respectively.
          //
          // In this case, if we've been looking for both types, we'd like to call it
          // a UPC-A code. But for efficiency we only run the EAN-13 decoder to also read
          // UPC-A. So we special case it here, and convert an EAN-13 result to a UPC-A
          // result if appropriate.
          //
          // But, don't return UPC-A if UPC-A was not a requested format!
          boolean ean13MayBeUPCA =
              result.getBarcodeFormat() == BarcodeFormat.EAN_13 &&
                  result.getText().charAt(0) == '0';
          @SuppressWarnings("unchecked")
          Collection<BarcodeFormat> possibleFormats =
              hints == null ? null : (Collection<BarcodeFormat>) hints.get(DecodeHintType.POSSIBLE_FORMATS);
          boolean canReturnUPCA = possibleFormats == null || possibleFormats.contains(BarcodeFormat.UPC_A);
    
          if (ean13MayBeUPCA && canReturnUPCA) {
            // Transfer the metadata across
            Result resultUPCA = new Result(result.getText().substring(1),
                                           result.getRawBytes(),
                                           result.getResultPoints(),
                                           BarcodeFormat.UPC_A);
            resultUPCA.putAllMetadata(result.getResultMetadata());
            return resultUPCA;
          }
          return result;
        } catch (ReaderException ignored) {
          // continue
        }
      }
  
      throw NotFoundException.getNotFoundInstance();
    }
  
    @Override
    public void reset() {
      for (Reader reader : readers) {
        reader.reset();
      }
    }
  
  }
  