public void GetQuestionShould_ErrorIfQuestionNotFound()
{
//Arrange
var questionId = "not an ID";
//Act + Assert
var ex = Assert.Throws <Exception>(() =>
formContext.GetQuestion(questionId));
ex.Message.Should().Contain("QuestionId cannot be found");
}
/// <summary>
/// Evaluates a condition against source data in formVM and returns true or false
/// </summary>
/// <param name="condition">Logic source</param>
/// /// <param name="formContext">Data source</param>
/// <returns></returns>
public static bool EvaluateCondition(ConditionVM condition, FormVM formContext)
{
var result = false;
//Load in condition parameters
var variableName = condition.Logic.Variable;
var answer = condition.Logic.Answer;
//var answerArray = condition.Logic.AnswerArray;
var answerArray = answer.Split('|');
//Find variable in session formContext
string variable = null;
switch (condition.Logic.Source)
{
case "answer":
variable = formContext.GetQuestion(variableName).Answer;
break;
case "formData":
if (formContext.SubmissionData == null)
{
throw new Exception("No submissionData found");
}
variable = formContext.SubmissionData.Where(d => d.Id == variableName)
.Select(d => d.Value).FirstOrDefault();
break;
default:
throw new ArgumentException($"Unrecognised variable source type {condition.Logic.Source} supplied by form");
break;
}
if (variable == null) //Whitespace is now explicitly allowed, to allow for checking of empty answers
{
throw new Exception($"Unable to resolve dynamic content variable {variableName}");
}
//Set result to true if condition is met | CONSIDER making all of these individual methods
switch (condition.Logic.Operator)
{
case "equal":
result = answerArray.Any(variable.Equals); //(variable == answer);
break;
case "is_empty":
result = string.IsNullOrWhiteSpace(variable);
break;
case "not_equal":
result = !(answerArray.Any(variable.Equals)); //(variable != answer);
break;
//TODO: Consider inclusion of 'includes' and other string functions
case "contains":
result = answerArray.Any(variable.Contains);
break;
case "contains_all":
result = answerArray.All(variable.Contains);
break;
case "greater_than":
try
{
result = (float.Parse(variable) > float.Parse(answer));
}
catch
{
throw new ArgumentException($"Variable or answer {variable} cannot be parsed to float");
}
break;
case "greater_than_or_equal":
try
{
result = (float.Parse(variable) >= float.Parse(answer));
}
catch
{
throw new ArgumentException($"Variable or answer {variable} cannot be parsed to float");
}
break;
case "less_than":
try
{
result = (float.Parse(variable) < float.Parse(answer));
}
catch
{
throw new ArgumentException($"Variable or answer {variable} cannot be parsed to float");
}
break;
case "less_than_or_equal":
try
{
result = (float.Parse(variable) <= float.Parse(answer));
}
catch
{
throw new ArgumentException($"Variable or answer {variable} cannot be parsed to float");
}
break;
default:
throw new ArgumentException($"Unrecognised logic operator {condition.Logic.Operator} supplied by form");
break;
}
return(result);
}