private static int ConvertNumberToDecimal(string inputValue, NumberSystem inputNumberSystem)
{
if (inputNumberSystem.FirstSymbolCollapses)
{
var reversedInputValue = inputValue.Reverse();
int decimalValue = reversedInputValue
.Select((ch, index) => GetDecimalValueOfCharacter(inputNumberSystem, index, ch))
.Sum();
return decimalValue;
}
else
{
var result = NonCollapsibleToDecimalConverter.Convert(new Number(inputNumberSystem, inputValue));
return result;
}
}
private static Number ConvertDecimalToNumberSystem(int decimalValue, NumberSystem outputNumberSystem)
{
return outputNumberSystem.FirstSymbolCollapses
? ConvertDecimalToCollapsibleNumberSystem(decimalValue, outputNumberSystem)
: ConvertDecimalToNonCollapsibleNumberSystem(decimalValue, outputNumberSystem);
}
private static int GetDecimalValueOfCharacter(NumberSystem inputNumberSystem, int index, char ch)
{
var radix = inputNumberSystem.Radix;
var coefficient = inputNumberSystem.NumberAlphabet.ToOrdinal(ch);
var value = coefficient*(int)Math.Pow(radix, index);
return value;
}
public static Number ConvertFromDecimal(int inputValue, NumberSystem outputNumberSystem)
{
if(outputNumberSystem.FirstSymbolType == FirstSymbolType.One)
CheckNotZero(inputValue);
return ConvertDecimalToNumberSystem(inputValue, outputNumberSystem);
}
public static Number Convert(string inputValue, NumberSystem inputNumberSystem, NumberSystem outputNumberSystem)
{
var decimalValue = ConvertNumberToDecimal(inputValue, inputNumberSystem);
var result = ConvertDecimalToNumberSystem(decimalValue, outputNumberSystem);
return result;
}
public static Number Convert(Number input, NumberSystem outputNumberSystem)
{
return Convert(input.Value, input.NumberSystem, outputNumberSystem);
}
private static Number ConvertDecimalToCollapsibleNumberSystem(int decimalValue, NumberSystem outputNumberSystem)
{
var radix = outputNumberSystem.Radix;
int number = decimalValue;
int divisionResult = 0;
int moduloResult = 0;
var result = new List<int>();
do
{
divisionResult = number / radix;
moduloResult = number % radix;
result.Add(moduloResult);
number = divisionResult;
}
while (divisionResult >= outputNumberSystem.Radix);
if (divisionResult > 0)
{
result.Add(divisionResult);
}
var symbolList = result.Select((value, index) => outputNumberSystem.NumberAlphabet.ToSymbol(value)).ToList();
symbolList.Reverse();
var resultString = symbolList.Aggregate(string.Empty, (s, c) => s += c);
return new Number(outputNumberSystem, resultString);
}
private static Number PadWithFirstSymbol(Number number, int requiredLength, NumberSystem numberSystem)
{
var currentValue = number.Value;
var currentLength = currentValue.Length;
var additionalCharsRequired = requiredLength - currentLength;
var paddingSymbol = numberSystem.NumberAlphabet.Alphabet[0];
var padding = new string(paddingSymbol, additionalCharsRequired);
var newValue = padding + currentValue;
return new Number(numberSystem, newValue);
}
private static Number ConvertDecimalToNonCollapsibleNumberSystem(int decimalValue, NumberSystem outputNumberSystem)
{
if (outputNumberSystem.FirstSymbolType == FirstSymbolType.One)
decimalValue--;
int radix = outputNumberSystem.Radix;
int iteration = 1;
int powerResult = 0, sumOfPowers = 0, newSumOfPowers = 0;
while (true)
{
powerResult = (int)Math.Pow(radix, iteration);
newSumOfPowers = sumOfPowers + powerResult;
if (decimalValue < newSumOfPowers) break;
sumOfPowers = newSumOfPowers;
iteration++;
}
var equivalentSymbolInCollapsibleSystem = decimalValue - sumOfPowers;
var newNumber = ConvertDecimalToCollapsibleNumberSystem(equivalentSymbolInCollapsibleSystem, outputNumberSystem);
var paddedNumber = PadWithFirstSymbol(newNumber, iteration, outputNumberSystem);
return paddedNumber;
}