/// <summary>
/// Interface implementaion. Returns an object with data for 'Metrics' and 'Dimensions' parameters of Google Analytics query by given lambda expression.
/// </summary>
/// <typeparam name="Tprop">Lambda expression selected member type</typeparam>
/// <param name="expression">Lambda expression</param>
/// <returns>String for 'Metrics' and 'Dimensions' parameters of Google Analytics</returns>
public SelectExpressionParserResult Parse <Tprop>(Expression <Func <ContextDataModel, Tprop> > expression)
{
var result = new SelectExpressionParserResult();
result.FieldsMap = new FieldsMap();
result.Dimensions = new List <string> ();
result.Metrics = new List <string>();
try
{
if (expression.Body is MemberInitExpression)
{
MemberInitExpression memberInitExpression = expression.Body as MemberInitExpression;
foreach (MemberAssignment binding in memberInitExpression.Bindings.Where(x => x is MemberAssignment))
{
string newName = binding.Member.Name;
MemberInfo member;
string fieldName = parseMemberExpression(binding.Expression, out member);
fillMap(result, member, newName, Constants.GOOGLE_ANALYTICS_PREFIX + fieldName);
}
}
else if (expression.Body is NewExpression)
{
NewExpression nex = expression.Body as NewExpression;
for (int i = 0; i < nex.Arguments.Count; i++)
{
MemberInfo member;
string fieldName = parseMemberExpression(nex.Arguments[i], out member);
fillMap(result, member, nex.Members[i].Name, Constants.GOOGLE_ANALYTICS_PREFIX + fieldName);
}
}
else
{
MemberInfo member;
string fieldName = parseMemberExpression(expression.Body, out member);
fillMap(result, member, fieldName, Constants.GOOGLE_ANALYTICS_PREFIX + fieldName);
}
}
catch (Exception ex)
{
throw new NotSupportedExpressionException(expression, "Invalid expression.", ex);
}
if (result.Metrics.Count == 0)
{
throw new NotSupportedExpressionException(expression, "No metrics are set.");
}
return(result);
}
private void fillMap(SelectExpressionParserResult result, MemberInfo member, string selectedObjectFieldName, string googleAnalyticsFieldName)
{
FieldsMapItem item = new FieldsMapItem()
{
ContextModelMember = member, ResultObjectMemberName = selectedObjectFieldName, ContextModelMemberName = googleAnalyticsFieldName
};
result.FieldsMap.Add(item);
if (item.IsDimension)
{
result.Dimensions.Add(googleAnalyticsFieldName);
}
else if (item.IsMetric)
{
result.Metrics.Add(googleAnalyticsFieldName);
}
}