public static State ProcessDigit(State currentState, int digit)
{
if (currentState.IsCalculated)
{
LogicManager.ResetState(currentState);
}
if (currentState.IsFractional)
{
currentState.FractionDigitCount++;
double fractionDivider = Math.Pow(10, currentState.FractionDigitCount);
if (currentState.CurrentValue < 0)
{
currentState.CurrentValue = currentState.CurrentValue - digit / fractionDivider;
}
else
{
currentState.CurrentValue = currentState.CurrentValue + digit / fractionDivider;
}
currentState.CurrentValue = Math.Round(currentState.CurrentValue, currentState.FractionDigitCount);
}
else
{
currentState.CurrentValue = currentState.CurrentValue * 10 + digit;
}
return currentState;
}
public Engine()
{
_state = new State();
_state.CurrentValueChanged += delegate(object sender, EventArgs e)
{
this.OnValueChanged(e);
};
}
private static void ResetState(State currentState)
{
currentState.PreviousValue = currentState.CurrentValue;
currentState.CurrentValue = 0;
currentState.FractionDigitCount = 0;
currentState.IsCalculated = false;
currentState.IsFractional = false;
currentState.IsSequentialEvaluation = false;
}
public State Evaluate(State currentState)
{
if (currentState.CurrentValue == 0)
{
throw new DivideByZeroException();
}
currentState.CurrentValue = currentState.PreviousValue / currentState.CurrentValue;
return currentState;
}
public State GetState(State currentState)
{
currentState.CurrentValue = 0;
currentState.FractionDigitCount = 0;
currentState.IsCalculated = false;
currentState.IsFractional = false;
currentState.IsSequentialEvaluation = false;
currentState.Operation = OperationManager.Empty;
currentState.PreviousValue = 0;
return currentState;
}
public State GetState(State currentState)
{
string currentValue = currentState.CurrentValue.ToString(CultureInfo.InvariantCulture);
int dotIndex = -1;
if (currentState.IsFractional)
{
dotIndex = currentValue.IndexOf('.');
if (dotIndex == -1)
{
currentValue += ".";
}
}
if (currentValue.Length == 1)
{
currentValue = "0";
}
else
{
currentValue = currentValue.Substring(0, currentValue.Length - 1);
dotIndex = currentValue.IndexOf('.');
if (dotIndex == -1)
{
currentState.FractionDigitCount = 0;
currentState.IsFractional = false;
}
else
{
currentState.FractionDigitCount = currentValue.Length - dotIndex - 1;
}
}
if (currentValue == "-")
{
currentValue = "0";
}
currentState.CurrentValue = double.Parse(currentValue, NumberStyles.Float, CultureInfo.InvariantCulture);
return currentState;
}
public static State Evaluate(State currentState)
{
double bufferCurrentValue;
if (!currentState.IsSequentialEvaluation)
{
currentState.IsSequentialEvaluation = true;
bufferCurrentValue = currentState.CurrentValue;
}
else
{
bufferCurrentValue = currentState.PreviousValue;
}
currentState = currentState.Operation.Evaluate(currentState);
currentState.IsCalculated = true;
currentState.PreviousValue = bufferCurrentValue;
return currentState;
}
public State GetState(State currentState)
{
return LogicManager.ProcessDigit(currentState, 5);
}
public State Evaluate(State currentState)
{
currentState.CurrentValue = currentState.PreviousValue - currentState.CurrentValue;
return currentState;
}
public State GetState(State currentState)
{
currentState.CurrentValue = 0;
return currentState;
}
public State GetState(State currentState)
{
currentState.CurrentValue = Math.Pow(currentState.CurrentValue, -1);
return currentState;
}
public State GetState(State currentState)
{
currentState = LogicManager.ProcessOperation(currentState, OperationManager.Plus);
return LogicManager.Evaluate(currentState);
}
public State GetState(State currentState)
{
return LogicManager.ProcessOperation(currentState, OperationManager.Divide);
}
public State GetState(State currentState)
{
currentState.IsFractional = true;
return currentState;
}
public static State ProcessOperation(State currentState, IOperation operation)
{
currentState.IsCalculated = true;
currentState.Operation = operation;
return currentState;
}
public State GetState(State currentState)
{
currentState.CurrentValue = currentState.PreviousValue * (currentState.CurrentValue / 100.0);
currentState.IsCalculated = true;
return currentState;
}
public State Evaluate(State currentState)
{
return currentState;
}
public State GetState(State currentState)
{
currentState.CurrentValue = Math.Sqrt(currentState.CurrentValue);
currentState.IsCalculated = true;
return currentState;
}
public State GetState(State currentState)
{
return LogicManager.Evaluate(currentState);
}
public State GetState(State currentState)
{
return LogicManager.ProcessOperation(currentState, OperationManager.Multiply);
}
public State Evaluate(State currentState)
{
return(currentState);
}