/*
* 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.
*/
using System;
namespace FastReport.Barcode.QRCode
{
  
  /*/// <author>  satorux@google.com (Satoru Takabayashi) - creator
  /// </author>
  /// <author>  dswitkin@google.com (Daniel Switkin) - ported from C++
  /// </author>
  /// <author>www.Redivivus.in (suraj.supekar@redivivus.in) - Ported from ZXING Java Source 
  /// </author>*/
  internal sealed class MaskUtil
  {
    
    private MaskUtil()
    {
      // do nothing
    }
    
    // Apply mask penalty rule 1 and return the penalty. Find repetitive cells with the same color and
    // give penalty to them. Example: 00000 or 11111.
    public static int applyMaskPenaltyRule1(ByteMatrix matrix)
    {
      return applyMaskPenaltyRule1Internal(matrix, true) + applyMaskPenaltyRule1Internal(matrix, false);
    }
    
    // Apply mask penalty rule 2 and return the penalty. Find 2x2 blocks with the same color and give
    // penalty to them.
    public static int applyMaskPenaltyRule2(ByteMatrix matrix)
    {
      int penalty = 0;
      sbyte[][] array = matrix.Array;
      int width = matrix.Width;
      int height = matrix.Height;
      for (int y = 0; y < height - 1; ++y)
      {
        for (int x = 0; x < width - 1; ++x)
        {
          int value_Renamed = array[y][x];
          if (value_Renamed == array[y][x + 1] && value_Renamed == array[y + 1][x] && value_Renamed == array[y + 1][x + 1])
          {
            penalty += 3;
          }
        }
      }
      return penalty;
    }
    
    // Apply mask penalty rule 3 and return the penalty. Find consecutive cells of 00001011101 or
    // 10111010000, and give penalty to them.  If we find patterns like 000010111010000, we give
    // penalties twice (i.e. 40 * 2).
    public static int applyMaskPenaltyRule3(ByteMatrix matrix)
    {
      int penalty = 0;
      sbyte[][] array = matrix.Array;
      int width = matrix.Width;
      int height = matrix.Height;
      for (int y = 0; y < height; ++y)
      {
        for (int x = 0; x < width; ++x)
        {
          // Tried to simplify following conditions but failed.
          if (x + 6 < width && array[y][x] == 1 && array[y][x + 1] == 0 && array[y][x + 2] == 1 && array[y][x + 3] == 1 && array[y][x + 4] == 1 && array[y][x + 5] == 0 && array[y][x + 6] == 1 && ((x + 10 < width && array[y][x + 7] == 0 && array[y][x + 8] == 0 && array[y][x + 9] == 0 && array[y][x + 10] == 0) || (x - 4 >= 0 && array[y][x - 1] == 0 && array[y][x - 2] == 0 && array[y][x - 3] == 0 && array[y][x - 4] == 0)))
          {
            penalty += 40;
          }
          if (y + 6 < height && array[y][x] == 1 && array[y + 1][x] == 0 && array[y + 2][x] == 1 && array[y + 3][x] == 1 && array[y + 4][x] == 1 && array[y + 5][x] == 0 && array[y + 6][x] == 1 && ((y + 10 < height && array[y + 7][x] == 0 && array[y + 8][x] == 0 && array[y + 9][x] == 0 && array[y + 10][x] == 0) || (y - 4 >= 0 && array[y - 1][x] == 0 && array[y - 2][x] == 0 && array[y - 3][x] == 0 && array[y - 4][x] == 0)))
          {
            penalty += 40;
          }
        }
      }
      return penalty;
    }
    
    // Apply mask penalty rule 4 and return the penalty. Calculate the ratio of dark cells and give
    // penalty if the ratio is far from 50%. It gives 10 penalty for 5% distance. Examples:
    // -   0% => 100
    // -  40% =>  20
    // -  45% =>  10
    // -  50% =>   0
    // -  55% =>  10
    // -  55% =>  20
    // - 100% => 100
    public static int applyMaskPenaltyRule4(ByteMatrix matrix)
    {
      int numDarkCells = 0;
      sbyte[][] array = matrix.Array;
      int width = matrix.Width;
      int height = matrix.Height;
      for (int y = 0; y < height; ++y)
      {
        for (int x = 0; x < width; ++x)
        {
          if (array[y][x] == 1)
          {
            numDarkCells += 1;
          }
        }
      }
      int numTotalCells = matrix.Height * matrix.Width;
      double darkRatio = (double) numDarkCells / numTotalCells;
      //UPGRADE_WARNING: Data types in Visual C# might be different.  Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
      return System.Math.Abs((int) (darkRatio * 100 - 50)) / 5 * 10;
    }
    
    // Return the mask bit for "getMaskPattern" at "x" and "y". See 8.8 of JISX0510:2004 for mask
    // pattern conditions.
    public static bool getDataMaskBit(int maskPattern, int x, int y)
    {
      if (!QRCode.isValidMaskPattern(maskPattern))
      {
        throw new System.ArgumentException("Invalid mask pattern");
      }
      int intermediate, temp;
      switch (maskPattern)
      {
        
        case 0: 
          intermediate = (y + x) & 0x1;
          break;
        
        case 1: 
          intermediate = y & 0x1;
          break;
        
        case 2: 
          intermediate = x % 3;
          break;
        
        case 3: 
          intermediate = (y + x) % 3;
          break;
        
        case 4: 
          intermediate = ((SupportClass.URShift(y, 1)) + (x / 3)) & 0x1;
          break;
        
        case 5: 
          temp = y * x;
          intermediate = (temp & 0x1) + (temp % 3);
          break;
        
        case 6: 
          temp = y * x;
          intermediate = (((temp & 0x1) + (temp % 3)) & 0x1);
          break;
        
        case 7: 
          temp = y * x;
          intermediate = (((temp % 3) + ((y + x) & 0x1)) & 0x1);
          break;
        
        default: 
          throw new System.ArgumentException("Invalid mask pattern: " + maskPattern);
        
      }
      return intermediate == 0;
    }
    
    // Helper function for applyMaskPenaltyRule1. We need this for doing this calculation in both
    // vertical and horizontal orders respectively.
    private static int applyMaskPenaltyRule1Internal(ByteMatrix matrix, bool isHorizontal)
    {
      int penalty = 0;
      int numSameBitCells = 0;
      int prevBit = - 1;
      // Horizontal mode:
      //   for (int i = 0; i < matrix.height(); ++i) {
      //     for (int j = 0; j < matrix.width(); ++j) {
      //       int bit = matrix.get(i, j);
      // Vertical mode:
      //   for (int i = 0; i < matrix.width(); ++i) {
      //     for (int j = 0; j < matrix.height(); ++j) {
      //       int bit = matrix.get(j, i);
      int iLimit = isHorizontal?matrix.Height:matrix.Width;
      int jLimit = isHorizontal?matrix.Width:matrix.Height;
      sbyte[][] array = matrix.Array;
      for (int i = 0; i < iLimit; ++i)
      {
        for (int j = 0; j < jLimit; ++j)
        {
          int bit = isHorizontal?array[i][j]:array[j][i];
          if (bit == prevBit)
          {
            numSameBitCells += 1;
            // Found five repetitive cells with the same color (bit).
            // We'll give penalty of 3.
            if (numSameBitCells == 5)
            {
              penalty += 3;
            }
            else if (numSameBitCells > 5)
            {
              // After five repetitive cells, we'll add the penalty one
              // by one.
              penalty += 1;
            }
          }
          else
          {
            numSameBitCells = 1; // Include the cell itself.
            prevBit = bit;
          }
        }
        numSameBitCells = 0; // Clear at each row/column.
      }
      return penalty;
    }
  }
}