protected override decimal GetValue()
{
decimal a = A.Value;
decimal b = B.Value;
return(OperatorUtils.Solve(OpType, a, b));
}
public MathValue ParseNext(Token[] tokens, int i, MathValue lastValue = null, int priority = 0)
{
Token token = tokens[i];
MathValue result;
if (OperatorUtils.IsOperator(token))
{
if (lastValue == null)
{
throw new Exception("Error");
}
i++;
OperationType op = OperatorUtils.GetOperatorTypeFromTokenType(token.Type);
result = new Operation(lastValue,
GetValueFromToken(tokens, ref i, priority),
op);
i++;
}
else
{
result = GetValueFromToken(tokens, ref i, priority);
i++;
}
if (i >= tokens.Length - 1)
{
return(result);
}
return(ParseNext(tokens, i, result, priority));
}
void printOp(MathValue val)
{
if (!(val is Operation))
{
Console.Write(val.Value);
}
else
{
Console.Write("[");
Operation op = (Operation)val;
if (op.A != null)
{
printOp(op.A);
Console.Write($"{OperatorUtils.ToString(op.OpType)}");
}
if (op.B != null)
{
printOp(op.B);
}
Console.Write("]");
}
}
private MathValue GetValueFromToken(Token[] tokens, ref int currentTokenIndex, int currentOperationPriority = 0)
{
Token current = tokens[currentTokenIndex];
MathValue currentTokenAsMathValue;
if (current.Type == TokenType.OpenParenthesis)
{
int openedParenthesis = 1;
List <Token> tokensInsideParenthesis = new List <Token>();
int j;
for (j = currentTokenIndex + 1; j < tokens.Length; j++)
{
Token innerToken = tokens[j];
if (innerToken.Type == TokenType.OpenParenthesis)
{
openedParenthesis++;
}
else if (innerToken.Type == TokenType.CloseParenthesis)
{
openedParenthesis--;
}
if (openedParenthesis == 0)
{
break;
}
tokensInsideParenthesis.Add(innerToken);
}
currentTokenAsMathValue = ParseNext(tokensInsideParenthesis.ToArray(), 0);
currentTokenIndex = j;
}
else
{
currentTokenAsMathValue = new MathValue(current.ToDecimalNumber());
}
if (currentTokenIndex >= tokens.Length - 1)
{
return(currentTokenAsMathValue);
}
else
{
// Speculate if next operation is a higher priority
// As number is received, next SHOULD be an operator
Token nextOperator = tokens[currentTokenIndex + 1];
OperationType operationType = OperatorUtils.GetOperatorTypeFromTokenType(nextOperator.Type);
int nextPriority = OperatorUtils.GetPriority(operationType);
if (nextPriority > currentOperationPriority)
{
// So, next operation will be evaluated as a single value
currentTokenIndex += 2;
return(new Operation(currentTokenAsMathValue, GetValueFromToken(
tokens,
ref currentTokenIndex,
nextPriority
), operationType));
}
return(currentTokenAsMathValue);
}
}