private SudokuGridPosition GetPosition(ushort cellDist, SudokuGridMetrics metrics)
{
for (byte i = 0; i < metrics.MaximumNumber; ++i)
{
for (byte j = 0; j < metrics.MaximumNumber; ++j)
{
if (metrics.MaximumNumber * i + j == cellDist)
{
return(new SudokuGridPosition(j, i, false));
}
}
}
return(Empty);
}
/// <summary>
/// Shifts this position for the specified number of cells.
/// </summary>
/// <param name="cellsShifting">Left shift performed if the value is negative;
/// right shift performed if the value is positive;
/// no shift performed if the value is 0.</param>
/// <param name="metrics">Metrics of the grid with this position.</param>
/// <returns></returns>
internal bool Shift(ushort cellsShifting, SudokuGridMetrics metrics)
{
if (cellsShifting == 0)
{
return(false);
}
int cellDist = metrics.MaximumNumber * Y + X;
bool crossedEarlier = crossedGridBorder;
this = GetPosition((ushort)((cellDist + cellsShifting) % metrics.CellsTotal), metrics);
if (crossedEarlier ||
!crossedGridBorder && ((cellDist + Math.Abs(cellsShifting)) / metrics.CellsTotal) == 1)
{
crossedGridBorder = true;
}
return(true);
}
/// <summary>
/// Creates binary file with compressed data.
/// </summary>
/// <param name="textFile">File with text representation of a grid.</param>
/// <param name="outputFilePath">Fully qualified name of output file.</param>
/// <param name="alg">Preferable compression algorithm.</param>
/// <returns>Seeked to the beginning binary file with read-write acessibilty
/// (existing file will be overwritten).</returns>
public static FileStream CreateBinaryFromText(FileStream textFile, string outputFilePath,
SudokuConvertionAlgorithm alg)
{
// TODO: ? duplicate functionality -- use ToBinary(FileStream, ...) instead
textFile.Position = 0;
string content = new StreamReader(textFile).ReadToEnd();
textFile.Position = 0;
var restrictions = SudokuGridConstraints.Traditional;
var metrics = new SudokuGridMetrics(9, 3, 3);
byte[] binary = SudokuConverter.ToBinary(content, alg, restrictions, metrics);
var outputFile = new FileStream(outputFilePath, FileMode.Create, FileAccess.ReadWrite);
outputFile.Write(binary, 0, binary.Length);
outputFile.Position = 0;
return outputFile;
}
protected SudokuGrid(SudokuGridConstraints constraints, byte maxNumber, byte blockWidth, byte blockHeight)
{
this.constraints = constraints;
metrics = new SudokuGridMetrics(maxNumber, blockWidth, blockHeight);
cells = new SudokuGridCell[maxNumber, maxNumber];
}
protected SudokuGrid(SudokuGridConstraints constraints, byte maxNumber, byte blockWidth, byte blockHeight)
{
this.constraints = constraints;
metrics = new SudokuGridMetrics(maxNumber, blockWidth, blockHeight);
cells = new SudokuGridCell[maxNumber, maxNumber];
}
public static byte[] ToBinary(string content, SudokuConvertionAlgorithm algorithm,
SudokuGridConstraints constraints, SudokuGridMetrics metrics)
{
byte[] compressedContent;
byte[] result;
switch (algorithm)
{
case SudokuConvertionAlgorithm.Uniform:
compressedContent = TextToBinaryUniform(content, metrics.MaximumNumber);
result = new byte[(constraints == SudokuGridConstraints.Traditional)
? HEADER_UNIFORM_LENGTH
: HEADER_UNIFORM_RESTRICTED_LENGTH
+ compressedContent.Length];
//if (constraints == SudokuGridConstraints.Traditional)
//{
// result = new byte[HEADER_UNIFORM_LENGTH + compressedContent.Length];
//}
//else
//{
// result = new byte[HEADER_UNIFORM_RESTRICTED_LENGTH + compressedContent.Length];
//}
result[0] = (byte)SudokuConvertionAlgorithm.Uniform;
result[1] = (byte)constraints;
result[2] = metrics.MaximumNumber;
result[3] = metrics.BlockWidth;
result[4] = metrics.BlockHeight;
if (constraints != SudokuGridConstraints.Traditional)
{
throw new NotImplementedException();
//var restrictionsPos = (ushort)();
//result[5] = (byte)();
}
Array.Copy(compressedContent, 0, result, (constraints == SudokuGridConstraints.Traditional)
? HEADER_UNIFORM_LENGTH
: HEADER_UNIFORM_RESTRICTED_LENGTH,
compressedContent.Length);
return result;
case SudokuConvertionAlgorithm.NonUniform:
ushort zerosPairsPos;
byte bitsPerPos;
byte bitsPerZerosQuantity;
compressedContent = TextToBinaryNonUniform(content, metrics.MaximumNumber, out zerosPairsPos,
out bitsPerPos, out bitsPerZerosQuantity);
result = new byte[(constraints == SudokuGridConstraints.Traditional)
? HEADER_NONUNIFORM_LENGTH
: HEADER_NONUNIFORM_RESTRICTED_LENGTH
+ compressedContent.Length];
result[0] = (byte)SudokuConvertionAlgorithm.NonUniform;
result[1] = (byte)(zerosPairsPos >> 8);
result[2] = (byte)zerosPairsPos;
result[3] = (byte)(((bitsPerPos - 1) << 4) | (bitsPerZerosQuantity - 1));
result[4] = (byte)constraints;
result[5] = metrics.MaximumNumber;
result[6] = metrics.BlockWidth;
result[7] = metrics.BlockHeight;
Array.Copy(compressedContent, 0, result, (constraints == SudokuGridConstraints.Traditional)
? HEADER_NONUNIFORM_LENGTH
: HEADER_NONUNIFORM_RESTRICTED_LENGTH,
compressedContent.Length);
//Array.Copy(compressedContent, 0, result, NONLINEAR_HEADER_LENGTH, compressedContent.Length);
return result;
default:
return null;
}
}
private static string BinaryNonUniformToText(byte[] data, SudokuGridMetrics metrics,
ushort zerosPairsPos, byte bitsPerPos, byte bitsPerZerosQuantity, SudokuGridConstraints constraints)
{
// extraction
var numbers = new byte[zerosPairsPos];
Array.Copy(data, 0, numbers, 0, zerosPairsPos);
numbers = DecompressNumbers(numbers, metrics.MaximumNumber);
if (numbers[numbers.Length - 1] == 0)
{
var nums = new byte[numbers.Length - 1];
Array.Copy(numbers, 0, nums, 0, nums.Length);
numbers = nums;
}
var zerosPairsCompressed = new byte[data.Length - zerosPairsPos];
Array.Copy(data, zerosPairsPos, zerosPairsCompressed, 0, zerosPairsCompressed.Length);
ushort[] zerosPairs = DecompressZerosPairs(zerosPairsCompressed, bitsPerPos,
bitsPerZerosQuantity);
// combining decompressed sequences
var sb = new StringBuilder(metrics.CellsTotal);
ushort j;
ushort indNumbers = 0;
ushort indZerosPairs = 0;
for (ushort i = 0; i < metrics.CellsTotal; )
{
if ((indZerosPairs < zerosPairs.Length) &&
(i < zerosPairs[indZerosPairs])) // possible numbers are at the beginning
{
sb.Append(numbers[indNumbers++]);
++i;
}
else if ((indZerosPairs < zerosPairs.Length) &&
(i == zerosPairs[indZerosPairs])) // zeros (either at the beginning or later)
{
indZerosPairs++;
for (j = 0; j < zerosPairs[indZerosPairs]; ++j, ++i)
{
sb.Append("0");
}
indZerosPairs++;
}
else // numbers are at the end
{
for (j = i; j < metrics.CellsTotal; ++j, ++i)
{
sb.Append(numbers[indNumbers++]);
}
}
}
return sb.ToString();
}
public static string ToText(FileStream binaryFile, out SudokuGridConstraints constraints,
out byte[] numbersKinds, out SudokuGridMetrics metrics)
{
var binary = new byte[binaryFile.Length];
binaryFile.Position = 0;
binaryFile.Read(binary, 0, (int)binaryFile.Length);
binaryFile.Position = 0;
return ToText(binary, out constraints, out numbersKinds, out metrics);
}
public static string ToText(byte[] binary, out SudokuGridConstraints constraints,
out byte[] numbersKinds, out SudokuGridMetrics metrics)
{
// !!! temporary !!!
numbersKinds = null;
var alg = (SudokuConvertionAlgorithm)(binary[0]);
byte[] data;
switch (alg)
{
case SudokuConvertionAlgorithm.Uniform:
constraints = (SudokuGridConstraints)(binary[1]);
metrics = new SudokuGridMetrics(binary[2], binary[3], binary[4]);
data = new byte[binary.Length - ((constraints == SudokuGridConstraints.Traditional)
? HEADER_UNIFORM_LENGTH
: HEADER_UNIFORM_RESTRICTED_LENGTH)];
Array.Copy(binary, (constraints == SudokuGridConstraints.Traditional)
? HEADER_UNIFORM_LENGTH
: HEADER_UNIFORM_RESTRICTED_LENGTH,
data, 0, data.Length);
return BinaryUniformToText(data, binary[2], constraints);
case SudokuConvertionAlgorithm.NonUniform:
var zerosPairsPos = (ushort)((binary[1] << 8) | binary[2]);
var bitsPerPos = (byte) ((binary[3] >> 4) + 1);
var bitsPerZerosQuantity = (byte) (((byte) (binary[3] << 4) >> 4) + 1);
constraints = (SudokuGridConstraints)(binary[4]);
metrics = new SudokuGridMetrics(binary[5], binary[6], binary[7]);
data = new byte[binary.Length - ((constraints == SudokuGridConstraints.Traditional)
? HEADER_NONUNIFORM_LENGTH
: HEADER_NONUNIFORM_RESTRICTED_LENGTH)];
Array.Copy(binary, (constraints == SudokuGridConstraints.Traditional)
? HEADER_NONUNIFORM_LENGTH
: HEADER_NONUNIFORM_RESTRICTED_LENGTH,
data, 0, data.Length);
return BinaryNonUniformToText(data, metrics, zerosPairsPos, bitsPerPos,
bitsPerZerosQuantity, constraints);
default:
// dummy code
constraints = SudokuGridConstraints.Traditional;
metrics = SudokuGridMetrics.Empty;
return null;
}
}