/// <summary>
/// For use with objects implementing INamedValueProvider (note, don't call from the INamedValueProvider unless you want to see a StackOverflowException).
/// If the sourceName contains ':' then it is split into the
/// parts since ':' is assumed to indicate hierarchy. example: foo:bar:fum means get the item bar from foo, and get item fum from bar.
/// </summary>
/// <param name="sourceName">The name of the value to get</param>
/// <param name="sourceObject">The object to get the value from </param>
/// <returns>Value if found, otherwise null</returns>
public static object GetNamedValue(string sourceName, INamedValueProvider sourceObject)
{
object sourceValue;
if (sourceName.Contains(":"))
{
string[] sourceParts = sourceName.Split(':');
if (sourceParts[0].ToLower() == "setting")
{
sourceValue = null; // TODO Settings.GetSetting(sourceParts[sourceParts.Length - 1]);
}
else
{
for (int i = 0; i < sourceParts.Length - 1; i++)
{
object subSourceObject = sourceObject.GetValue(sourceParts[i]);
if (subSourceObject is INamedValueProvider)
{
sourceObject = (INamedValueProvider)subSourceObject;
}
}
sourceValue = sourceObject.GetValue(sourceParts[sourceParts.Length - 1]);
}
}
else
{
sourceValue = sourceObject.GetValue(sourceName);
}
return sourceValue;
}
public bool Evaluate(INamedValueProvider sourceObject)
{
object sourceValue = General.GetNamedValue(Source, sourceObject);
bool result = false;
if (sourceValue == null)
{
if (Operator == "isnull")
{
result = true;
}
}
else
{
if (Operator == "in" || Operator == "notin")
{
string sourceValueAsString = sourceValue.ToString();
result = sourceValueAsString.Length>0 && Operand.IndexOf(sourceValueAsString, StringComparison.CurrentCultureIgnoreCase) > -1;
if (Operator == "notin")
{
result = !result;
}
}
else
{
object convertedCompareValue;
try
{
convertedCompareValue = General.ChangeType(Operand, sourceValue.GetType());
}
catch (Exception ex)
{
//this happens when source is enum but not the supplied value
//as it can't be compared to enum source it doesn't matter whether supplied value is null or any other value
//assign null value as there is no difference.
convertedCompareValue = null;
}
switch (Operator)
{
case "equals":
case "equal":
case "eq":
case "==":
case "=":
case "notequal":
case "!=":
if (sourceValue is IComparable)
{
if (isDateType(sourceValue, convertedCompareValue))
{
TimeSpan ts = (DateTime)sourceValue - (DateTime)convertedCompareValue;
result = false;
if (ts.Seconds == 0 && ts.Minutes == 0 && ts.Hours == 0 && ts.Days == 0)
result = true;
}
else
{
if (sourceValue != null && convertedCompareValue != null)
{
result = ((IComparable)sourceValue.ToString().ToLower()).CompareTo(convertedCompareValue.ToString().ToLower()) == 0;
}
else
{
result = ((IComparable)sourceValue).CompareTo(convertedCompareValue) == 0;
}
}
}
else
{
result = sourceValue == convertedCompareValue;
}
if (Operator == "notequal" || Operator == "!=")
{
result = !result;
}
break;
case "<":
case "lt":
case "lessthan":
if (isDateType(sourceValue, convertedCompareValue))
{
result = false;
// Less than zero t1 is less than t2. Zero t1 equals t2. Greater than zero t1
// is greater than t2.
if (DateTime.Compare((DateTime)sourceValue,(DateTime)convertedCompareValue) < 0)
result = true;
}
else
{
if (sourceValue != null && convertedCompareValue != null)
{
result = ((IComparable)sourceValue.ToString().ToLower()).CompareTo(convertedCompareValue.ToString().ToLower()) < 0;
}
else
{
result = ((IComparable)sourceValue).CompareTo(convertedCompareValue) < 0;
}
}
break;
case "<=":
case "lteq":
if (isDateType(sourceValue, convertedCompareValue))
{
result = false;
if (DateTime.Compare((DateTime)sourceValue, (DateTime)convertedCompareValue) <= 0)
result = true;
}
else
{
if (sourceValue != null && convertedCompareValue != null)
{
result = ((IComparable)sourceValue.ToString().ToLower()).CompareTo(convertedCompareValue.ToString().ToLower()) <= 0;
}
else
{
result = ((IComparable)sourceValue).CompareTo(convertedCompareValue) <= 0;
}
}
break;
case ">":
case "gt":
case "greaterthan":
if (isDateType(sourceValue, convertedCompareValue))
{
result = false;
if (DateTime.Compare((DateTime)sourceValue, (DateTime)convertedCompareValue) > 0)
result = true;
}
else
{
if (sourceValue != null && convertedCompareValue != null)
{
result = ((IComparable)sourceValue.ToString().ToLower()).CompareTo(convertedCompareValue.ToString().ToLower()) > 0;
}
else
{
result = ((IComparable)sourceValue).CompareTo(convertedCompareValue) > 0;
}
}
break;
case ">=":
case "gteq":
if (isDateType(sourceValue, convertedCompareValue))
{
result = false;
if (DateTime.Compare((DateTime)sourceValue, (DateTime)convertedCompareValue) >= 0)
result = true;
}
else
{
if (sourceValue != null && convertedCompareValue != null)
{
result = ((IComparable)sourceValue.ToString().ToLower()).CompareTo(convertedCompareValue.ToString().ToLower()) >= 0;
}
else
{
result = ((IComparable)sourceValue).CompareTo(convertedCompareValue) >= 0;
}
}
break;
}
}
}
return result;
}
public static bool EvaluateConditions(List<Condition> conditions, INamedValueProvider sourceObject)
{
bool? overallResult = null;
foreach (Condition condition in conditions)
{
bool result = condition.Evaluate(sourceObject);
if (string.IsNullOrEmpty(condition.Relation) || condition.Relation == "and")
{
if (overallResult.HasValue)
overallResult = overallResult.Value && result;
else
overallResult = result;
}
else if (condition.Relation == "or")
{
if (overallResult.HasValue)
{
if (result)
{
overallResult = true;
}
}
else
{
overallResult = result;
}
}
}
return overallResult.HasValue ? overallResult.Value : false;
}
