/*
 * 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.google.zxing.qrcode.decoder;

import com.google.zxing.FormatException;
import com.google.zxing.common.BitMatrix;

/**
 * See ISO 18004:2006 Annex D
 *
 * @author Sean Owen
 */
public final class Version {

  /**
   * See ISO 18004:2006 Annex D.
   * Element i represents the raw version bits that specify version i + 7
   */
  private static final int[] VERSION_DECODE_INFO = {
      0x07C94, 0x085BC, 0x09A99, 0x0A4D3, 0x0BBF6,
      0x0C762, 0x0D847, 0x0E60D, 0x0F928, 0x10B78,
      0x1145D, 0x12A17, 0x13532, 0x149A6, 0x15683,
      0x168C9, 0x177EC, 0x18EC4, 0x191E1, 0x1AFAB,
      0x1B08E, 0x1CC1A, 0x1D33F, 0x1ED75, 0x1F250,
      0x209D5, 0x216F0, 0x228BA, 0x2379F, 0x24B0B,
      0x2542E, 0x26A64, 0x27541, 0x28C69
  };

  private static final Version[] VERSIONS = buildVersions();

  private final int versionNumber;
  private final int[] alignmentPatternCenters;
  private final ECBlocks[] ecBlocks;
  private final int totalCodewords;

  private Version(int versionNumber,
                  int[] alignmentPatternCenters,
                  ECBlocks... ecBlocks) {
    this.versionNumber = versionNumber;
    this.alignmentPatternCenters = alignmentPatternCenters;
    this.ecBlocks = ecBlocks;
    int total = 0;
    int ecCodewords = ecBlocks[0].getECCodewordsPerBlock();
    ECB[] ecbArray = ecBlocks[0].getECBlocks();
    for (ECB ecBlock : ecbArray) {
      total += ecBlock.getCount() * (ecBlock.getDataCodewords() + ecCodewords);
    }
    this.totalCodewords = total;
  }

  public int getVersionNumber() {
    return versionNumber;
  }

  public int[] getAlignmentPatternCenters() {
    return alignmentPatternCenters;
  }

  public int getTotalCodewords() {
    return totalCodewords;
  }

  public int getDimensionForVersion() {
    return 17 + 4 * versionNumber;
  }

  public ECBlocks getECBlocksForLevel(ErrorCorrectionLevel ecLevel) {
    return ecBlocks[ecLevel.ordinal()];
  }

  /**
   * <p>Deduces version information purely from QR Code dimensions.</p>
   *
   * @param dimension dimension in modules
   * @return Version for a QR Code of that dimension
   * @throws FormatException if dimension is not 1 mod 4
   */
  public static Version getProvisionalVersionForDimension(int dimension) throws FormatException {
    if (dimension % 4 != 1) {
      throw FormatException.getFormatInstance();
    }
    try {
      return getVersionForNumber((dimension - 17) / 4);
    } catch (IllegalArgumentException ignored) {
      throw FormatException.getFormatInstance();
    }
  }

  public static Version getVersionForNumber(int versionNumber) {
    if (versionNumber < 1 || versionNumber > 40) {
      throw new IllegalArgumentException();
    }
    return VERSIONS[versionNumber - 1];
  }

  static Version decodeVersionInformation(int versionBits) {
    int bestDifference = Integer.MAX_VALUE;
    int bestVersion = 0;
    for (int i = 0; i < VERSION_DECODE_INFO.length; i++) {
      int targetVersion = VERSION_DECODE_INFO[i];
      // Do the version info bits match exactly? done.
      if (targetVersion == versionBits) {
        return getVersionForNumber(i + 7);
      }
      // Otherwise see if this is the closest to a real version info bit string
      // we have seen so far
      int bitsDifference = FormatInformation.numBitsDiffering(versionBits, targetVersion);
      if (bitsDifference < bestDifference) {
        bestVersion = i + 7;
        bestDifference = bitsDifference;
      }
    }
    // We can tolerate up to 3 bits of error since no two version info codewords will
    // differ in less than 8 bits.
    if (bestDifference <= 3) {
      return getVersionForNumber(bestVersion);
    }
    // If we didn't find a close enough match, fail
    return null;
  }

  /**
   * See ISO 18004:2006 Annex E
   */
  BitMatrix buildFunctionPattern() {
    int dimension = getDimensionForVersion();
    BitMatrix bitMatrix = new BitMatrix(dimension);

    // Top left finder pattern + separator + format
    bitMatrix.setRegion(0, 0, 9, 9);
    // Top right finder pattern + separator + format
    bitMatrix.setRegion(dimension - 8, 0, 8, 9);
    // Bottom left finder pattern + separator + format
    bitMatrix.setRegion(0, dimension - 8, 9, 8);

    // Alignment patterns
    int max = alignmentPatternCenters.length;
    for (int x = 0; x < max; x++) {
      int i = alignmentPatternCenters[x] - 2;
      for (int y = 0; y < max; y++) {
        if ((x == 0 && (y == 0 || y == max - 1)) || (x == max - 1 && y == 0)) {
          // No alignment patterns near the three finder patterns
          continue;
        }
        bitMatrix.setRegion(alignmentPatternCenters[y] - 2, i, 5, 5);
      }
    }

    // Vertical timing pattern
    bitMatrix.setRegion(6, 9, 1, dimension - 17);
    // Horizontal timing pattern
    bitMatrix.setRegion(9, 6, dimension - 17, 1);

    if (versionNumber > 6) {
      // Version info, top right
      bitMatrix.setRegion(dimension - 11, 0, 3, 6);
      // Version info, bottom left
      bitMatrix.setRegion(0, dimension - 11, 6, 3);
    }

    return bitMatrix;
  }

  /**
   * <p>Encapsulates a set of error-correction blocks in one symbol version. Most versions will
   * use blocks of differing sizes within one version, so, this encapsulates the parameters for
   * each set of blocks. It also holds the number of error-correction codewords per block since it
   * will be the same across all blocks within one version.</p>
   */
  public static final class ECBlocks {
    private final int ecCodewordsPerBlock;
    private final ECB[] ecBlocks;

    ECBlocks(int ecCodewordsPerBlock, ECB... ecBlocks) {
      this.ecCodewordsPerBlock = ecCodewordsPerBlock;
      this.ecBlocks = ecBlocks;
    }

    public int getECCodewordsPerBlock() {
      return ecCodewordsPerBlock;
    }

    public int getNumBlocks() {
      int total = 0;
      for (ECB ecBlock : ecBlocks) {
        total += ecBlock.getCount();
      }
      return total;
    }

    public int getTotalECCodewords() {
      return ecCodewordsPerBlock * getNumBlocks();
    }

    public ECB[] getECBlocks() {
      return ecBlocks;
    }
  }

  /**
   * <p>Encapsulates the parameters for one error-correction block in one symbol version.
   * This includes the number of data codewords, and the number of times a block with these
   * parameters is used consecutively in the QR code version's format.</p>
   */
  public static final class ECB {
    private final int count;
    private final int dataCodewords;

    ECB(int count, int dataCodewords) {
      this.count = count;
      this.dataCodewords = dataCodewords;
    }

    public int getCount() {
      return count;
    }

    public int getDataCodewords() {
      return dataCodewords;
    }
  }

  @Override
  public String toString() {
    return String.valueOf(versionNumber);
  }

  /**
   * See ISO 18004:2006 6.5.1 Table 9
   */
  private static Version[] buildVersions() {
    return new Version[]{
        new Version(1, new int[]{},
            new ECBlocks(7, new ECB(1, 19)),
            new ECBlocks(10, new ECB(1, 16)),
            new ECBlocks(13, new ECB(1, 13)),
            new ECBlocks(17, new ECB(1, 9))),
        new Version(2, new int[]{6, 18},
            new ECBlocks(10, new ECB(1, 34)),
            new ECBlocks(16, new ECB(1, 28)),
            new ECBlocks(22, new ECB(1, 22)),
            new ECBlocks(28, new ECB(1, 16))),
        new Version(3, new int[]{6, 22},
            new ECBlocks(15, new ECB(1, 55)),
            new ECBlocks(26, new ECB(1, 44)),
            new ECBlocks(18, new ECB(2, 17)),
            new ECBlocks(22, new ECB(2, 13))),
        new Version(4, new int[]{6, 26},
            new ECBlocks(20, new ECB(1, 80)),
            new ECBlocks(18, new ECB(2, 32)),
            new ECBlocks(26, new ECB(2, 24)),
            new ECBlocks(16, new ECB(4, 9))),
        new Version(5, new int[]{6, 30},
            new ECBlocks(26, new ECB(1, 108)),
            new ECBlocks(24, new ECB(2, 43)),
            new ECBlocks(18, new ECB(2, 15),
                new ECB(2, 16)),
            new ECBlocks(22, new ECB(2, 11),
                new ECB(2, 12))),
        new Version(6, new int[]{6, 34},
            new ECBlocks(18, new ECB(2, 68)),
            new ECBlocks(16, new ECB(4, 27)),
            new ECBlocks(24, new ECB(4, 19)),
            new ECBlocks(28, new ECB(4, 15))),
        new Version(7, new int[]{6, 22, 38},
            new ECBlocks(20, new ECB(2, 78)),
            new ECBlocks(18, new ECB(4, 31)),
            new ECBlocks(18, new ECB(2, 14),
                new ECB(4, 15)),
            new ECBlocks(26, new ECB(4, 13),
                new ECB(1, 14))),
        new Version(8, new int[]{6, 24, 42},
            new ECBlocks(24, new ECB(2, 97)),
            new ECBlocks(22, new ECB(2, 38),
                new ECB(2, 39)),
            new ECBlocks(22, new ECB(4, 18),
                new ECB(2, 19)),
            new ECBlocks(26, new ECB(4, 14),
                new ECB(2, 15))),
        new Version(9, new int[]{6, 26, 46},
            new ECBlocks(30, new ECB(2, 116)),
            new ECBlocks(22, new ECB(3, 36),
                new ECB(2, 37)),
            new ECBlocks(20, new ECB(4, 16),
                new ECB(4, 17)),
            new ECBlocks(24, new ECB(4, 12),
                new ECB(4, 13))),
        new Version(10, new int[]{6, 28, 50},
            new ECBlocks(18, new ECB(2, 68),
                new ECB(2, 69)),
            new ECBlocks(26, new ECB(4, 43),
                new ECB(1, 44)),
            new ECBlocks(24, new ECB(6, 19),
                new ECB(2, 20)),
            new ECBlocks(28, new ECB(6, 15),
                new ECB(2, 16))),
        new Version(11, new int[]{6, 30, 54},
            new ECBlocks(20, new ECB(4, 81)),
            new ECBlocks(30, new ECB(1, 50),
                new ECB(4, 51)),
            new ECBlocks(28, new ECB(4, 22),
                new ECB(4, 23)),
            new ECBlocks(24, new ECB(3, 12),
                new ECB(8, 13))),
        new Version(12, new int[]{6, 32, 58},
            new ECBlocks(24, new ECB(2, 92),
                new ECB(2, 93)),
            new ECBlocks(22, new ECB(6, 36),
                new ECB(2, 37)),
            new ECBlocks(26, new ECB(4, 20),
                new ECB(6, 21)),
            new ECBlocks(28, new ECB(7, 14),
                new ECB(4, 15))),
        new Version(13, new int[]{6, 34, 62},
            new ECBlocks(26, new ECB(4, 107)),
            new ECBlocks(22, new ECB(8, 37),
                new ECB(1, 38)),
            new ECBlocks(24, new ECB(8, 20),
                new ECB(4, 21)),
            new ECBlocks(22, new ECB(12, 11),
                new ECB(4, 12))),
        new Version(14, new int[]{6, 26, 46, 66},
            new ECBlocks(30, new ECB(3, 115),
                new ECB(1, 116)),
            new ECBlocks(24, new ECB(4, 40),
                new ECB(5, 41)),
            new ECBlocks(20, new ECB(11, 16),
                new ECB(5, 17)),
            new ECBlocks(24, new ECB(11, 12),
                new ECB(5, 13))),
        new Version(15, new int[]{6, 26, 48, 70},
            new ECBlocks(22, new ECB(5, 87),
                new ECB(1, 88)),
            new ECBlocks(24, new ECB(5, 41),
                new ECB(5, 42)),
            new ECBlocks(30, new ECB(5, 24),
                new ECB(7, 25)),
            new ECBlocks(24, new ECB(11, 12),
                new ECB(7, 13))),
        new Version(16, new int[]{6, 26, 50, 74},
            new ECBlocks(24, new ECB(5, 98),
                new ECB(1, 99)),
            new ECBlocks(28, new ECB(7, 45),
                new ECB(3, 46)),
            new ECBlocks(24, new ECB(15, 19),
                new ECB(2, 20)),
            new ECBlocks(30, new ECB(3, 15),
                new ECB(13, 16))),
        new Version(17, new int[]{6, 30, 54, 78},
            new ECBlocks(28, new ECB(1, 107),
                new ECB(5, 108)),
            new ECBlocks(28, new ECB(10, 46),
                new ECB(1, 47)),
            new ECBlocks(28, new ECB(1, 22),
                new ECB(15, 23)),
            new ECBlocks(28, new ECB(2, 14),
                new ECB(17, 15))),
        new Version(18, new int[]{6, 30, 56, 82},
            new ECBlocks(30, new ECB(5, 120),
                new ECB(1, 121)),
            new ECBlocks(26, new ECB(9, 43),
                new ECB(4, 44)),
            new ECBlocks(28, new ECB(17, 22),
                new ECB(1, 23)),
            new ECBlocks(28, new ECB(2, 14),
                new ECB(19, 15))),
        new Version(19, new int[]{6, 30, 58, 86},
            new ECBlocks(28, new ECB(3, 113),
                new ECB(4, 114)),
            new ECBlocks(26, new ECB(3, 44),
                new ECB(11, 45)),
            new ECBlocks(26, new ECB(17, 21),
                new ECB(4, 22)),
            new ECBlocks(26, new ECB(9, 13),
                new ECB(16, 14))),
        new Version(20, new int[]{6, 34, 62, 90},
            new ECBlocks(28, new ECB(3, 107),
                new ECB(5, 108)),
            new ECBlocks(26, new ECB(3, 41),
                new ECB(13, 42)),
            new ECBlocks(30, new ECB(15, 24),
                new ECB(5, 25)),
            new ECBlocks(28, new ECB(15, 15),
                new ECB(10, 16))),
        new Version(21, new int[]{6, 28, 50, 72, 94},
            new ECBlocks(28, new ECB(4, 116),
                new ECB(4, 117)),
            new ECBlocks(26, new ECB(17, 42)),
            new ECBlocks(28, new ECB(17, 22),
                new ECB(6, 23)),
            new ECBlocks(30, new ECB(19, 16),
                new ECB(6, 17))),
        new Version(22, new int[]{6, 26, 50, 74, 98},
            new ECBlocks(28, new ECB(2, 111),
                new ECB(7, 112)),
            new ECBlocks(28, new ECB(17, 46)),
            new ECBlocks(30, new ECB(7, 24),
                new ECB(16, 25)),
            new ECBlocks(24, new ECB(34, 13))),
        new Version(23, new int[]{6, 30, 54, 78, 102},
            new ECBlocks(30, new ECB(4, 121),
                new ECB(5, 122)),
            new ECBlocks(28, new ECB(4, 47),
                new ECB(14, 48)),
            new ECBlocks(30, new ECB(11, 24),
                new ECB(14, 25)),
            new ECBlocks(30, new ECB(16, 15),
                new ECB(14, 16))),
        new Version(24, new int[]{6, 28, 54, 80, 106},
            new ECBlocks(30, new ECB(6, 117),
                new ECB(4, 118)),
            new ECBlocks(28, new ECB(6, 45),
                new ECB(14, 46)),
            new ECBlocks(30, new ECB(11, 24),
                new ECB(16, 25)),
            new ECBlocks(30, new ECB(30, 16),
                new ECB(2, 17))),
        new Version(25, new int[]{6, 32, 58, 84, 110},
            new ECBlocks(26, new ECB(8, 106),
                new ECB(4, 107)),
            new ECBlocks(28, new ECB(8, 47),
                new ECB(13, 48)),
            new ECBlocks(30, new ECB(7, 24),
                new ECB(22, 25)),
            new ECBlocks(30, new ECB(22, 15),
                new ECB(13, 16))),
        new Version(26, new int[]{6, 30, 58, 86, 114},
            new ECBlocks(28, new ECB(10, 114),
                new ECB(2, 115)),
            new ECBlocks(28, new ECB(19, 46),
                new ECB(4, 47)),
            new ECBlocks(28, new ECB(28, 22),
                new ECB(6, 23)),
            new ECBlocks(30, new ECB(33, 16),
                new ECB(4, 17))),
        new Version(27, new int[]{6, 34, 62, 90, 118},
            new ECBlocks(30, new ECB(8, 122),
                new ECB(4, 123)),
            new ECBlocks(28, new ECB(22, 45),
                new ECB(3, 46)),
            new ECBlocks(30, new ECB(8, 23),
                new ECB(26, 24)),
            new ECBlocks(30, new ECB(12, 15),
                new ECB(28, 16))),
        new Version(28, new int[]{6, 26, 50, 74, 98, 122},
            new ECBlocks(30, new ECB(3, 117),
                new ECB(10, 118)),
            new ECBlocks(28, new ECB(3, 45),
                new ECB(23, 46)),
            new ECBlocks(30, new ECB(4, 24),
                new ECB(31, 25)),
            new ECBlocks(30, new ECB(11, 15),
                new ECB(31, 16))),
        new Version(29, new int[]{6, 30, 54, 78, 102, 126},
            new ECBlocks(30, new ECB(7, 116),
                new ECB(7, 117)),
            new ECBlocks(28, new ECB(21, 45),
                new ECB(7, 46)),
            new ECBlocks(30, new ECB(1, 23),
                new ECB(37, 24)),
            new ECBlocks(30, new ECB(19, 15),
                new ECB(26, 16))),
        new Version(30, new int[]{6, 26, 52, 78, 104, 130},
            new ECBlocks(30, new ECB(5, 115),
                new ECB(10, 116)),
            new ECBlocks(28, new ECB(19, 47),
                new ECB(10, 48)),
            new ECBlocks(30, new ECB(15, 24),
                new ECB(25, 25)),
            new ECBlocks(30, new ECB(23, 15),
                new ECB(25, 16))),
        new Version(31, new int[]{6, 30, 56, 82, 108, 134},
            new ECBlocks(30, new ECB(13, 115),
                new ECB(3, 116)),
            new ECBlocks(28, new ECB(2, 46),
                new ECB(29, 47)),
            new ECBlocks(30, new ECB(42, 24),
                new ECB(1, 25)),
            new ECBlocks(30, new ECB(23, 15),
                new ECB(28, 16))),
        new Version(32, new int[]{6, 34, 60, 86, 112, 138},
            new ECBlocks(30, new ECB(17, 115)),
            new ECBlocks(28, new ECB(10, 46),
                new ECB(23, 47)),
            new ECBlocks(30, new ECB(10, 24),
                new ECB(35, 25)),
            new ECBlocks(30, new ECB(19, 15),
                new ECB(35, 16))),
        new Version(33, new int[]{6, 30, 58, 86, 114, 142},
            new ECBlocks(30, new ECB(17, 115),
                new ECB(1, 116)),
            new ECBlocks(28, new ECB(14, 46),
                new ECB(21, 47)),
            new ECBlocks(30, new ECB(29, 24),
                new ECB(19, 25)),
            new ECBlocks(30, new ECB(11, 15),
                new ECB(46, 16))),
        new Version(34, new int[]{6, 34, 62, 90, 118, 146},
            new ECBlocks(30, new ECB(13, 115),
                new ECB(6, 116)),
            new ECBlocks(28, new ECB(14, 46),
                new ECB(23, 47)),
            new ECBlocks(30, new ECB(44, 24),
                new ECB(7, 25)),
            new ECBlocks(30, new ECB(59, 16),
                new ECB(1, 17))),
        new Version(35, new int[]{6, 30, 54, 78, 102, 126, 150},
            new ECBlocks(30, new ECB(12, 121),
                new ECB(7, 122)),
            new ECBlocks(28, new ECB(12, 47),
                new ECB(26, 48)),
            new ECBlocks(30, new ECB(39, 24),
                new ECB(14, 25)),
            new ECBlocks(30, new ECB(22, 15),
                new ECB(41, 16))),
        new Version(36, new int[]{6, 24, 50, 76, 102, 128, 154},
            new ECBlocks(30, new ECB(6, 121),
                new ECB(14, 122)),
            new ECBlocks(28, new ECB(6, 47),
                new ECB(34, 48)),
            new ECBlocks(30, new ECB(46, 24),
                new ECB(10, 25)),
            new ECBlocks(30, new ECB(2, 15),
                new ECB(64, 16))),
        new Version(37, new int[]{6, 28, 54, 80, 106, 132, 158},
            new ECBlocks(30, new ECB(17, 122),
                new ECB(4, 123)),
            new ECBlocks(28, new ECB(29, 46),
                new ECB(14, 47)),
            new ECBlocks(30, new ECB(49, 24),
                new ECB(10, 25)),
            new ECBlocks(30, new ECB(24, 15),
                new ECB(46, 16))),
        new Version(38, new int[]{6, 32, 58, 84, 110, 136, 162},
            new ECBlocks(30, new ECB(4, 122),
                new ECB(18, 123)),
            new ECBlocks(28, new ECB(13, 46),
                new ECB(32, 47)),
            new ECBlocks(30, new ECB(48, 24),
                new ECB(14, 25)),
            new ECBlocks(30, new ECB(42, 15),
                new ECB(32, 16))),
        new Version(39, new int[]{6, 26, 54, 82, 110, 138, 166},
            new ECBlocks(30, new ECB(20, 117),
                new ECB(4, 118)),
            new ECBlocks(28, new ECB(40, 47),
                new ECB(7, 48)),
            new ECBlocks(30, new ECB(43, 24),
                new ECB(22, 25)),
            new ECBlocks(30, new ECB(10, 15),
                new ECB(67, 16))),
        new Version(40, new int[]{6, 30, 58, 86, 114, 142, 170},
            new ECBlocks(30, new ECB(19, 118),
                new ECB(6, 119)),
            new ECBlocks(28, new ECB(18, 47),
                new ECB(31, 48)),
            new ECBlocks(30, new ECB(34, 24),
                new ECB(34, 25)),
            new ECBlocks(30, new ECB(20, 15),
                new ECB(61, 16)))
    };
  }

}
