/// <summary>
/// Parses the specified list of tokens with appropriate logic to convert
/// it into a Dice instance to evaluate oprations on.
/// </summary>
/// <param name="expression">dice expression rolled</param>
/// <param name="tokens">String expression to parse</param>
/// <param name="dieRoller">Die roller to use</param>
/// <returns>Dice result</returns>
private DiceResult ParseLogic(string expression, List <string> tokens, IDieRoller dieRoller)
{
List <TermResult> results = new List <TermResult>();
while (tokens.IndexOf(this.GroupStartOperator) != -1)
{
// getting data between grouping symbols: "(" and ")"
int open = tokens.LastIndexOf(this.GroupStartOperator);
int close = tokens.IndexOf(this.GroupEndOperator, open);
if (open >= close)
{
throw new ArithmeticException("No matching close-open parenthesis.");
}
// get a subexpression list for elements within the grouping symbols
List <string> subExpression = new List <string>();
for (var i = open + 1; i < close; i++)
{
subExpression.Add(tokens[i]);
}
// run the operations on the subexpression
int subValue = this.HandleBasicOperation(results, subExpression, dieRoller);
// when subexpression calculation is done, replace the grouping start symbol
// and removing the tokens for the subexpression from the token list
tokens[open] = subValue.ToString();
tokens.RemoveRange(open + 1, close - open);
}
// at this point, we should have replaced all groups in the expression
// with the appropriate values, so need to calculate last simple expression
int value = this.HandleBasicOperation(results, tokens, dieRoller);
// now return the dice result from the final value and TermResults list
return(new DiceResult(expression, value, results, dieRoller.GetType().ToString(), this.config));
}
/// <inheritdoc/>
public DiceResult Roll(IDieRoller dieRoller)
{
List <TermResult> termResults = this.terms.SelectMany(t => t.CalculateResults(dieRoller)).ToList();
return(new DiceResult(this.ToString(), termResults, dieRoller.GetType().ToString(), this.Configuration));
}