/// <summary>
/// Helper method to return the next step based on the specified
/// rule. Called after we've determined that the rule applies.
/// </summary>
/// <returns>The rule based next.</returns>
/// <param name="dbConn">connection to the underlying database</param>
/// <param name="rule">the matching rule</param>
public static Step GetRuleBasedNext(IDbConnection dbConn, Db.Rule rule)
{
if (rule == null)
{
throw new ArgumentNullException("rule");
}
var tmp = Step.Select(dbConn, rule.NextStepId);
if (tmp == null)
{
var msg = new StringBuilder();
msg.Append("internal error: the rule applies ");
msg.Append("but we can't find next step #");
msg.Append(rule.NextStepId);
msg.Append(" in the database [");
msg.Append(rule.ToString());
msg.Append("]");
throw new Exception(msg.ToString());
}
return(tmp);
}
/// <summary>
/// Returns true iff the value in the rule satisfies the value in
/// the item.
/// For example, if the rule says foo!=someValue, and the item
/// has the value in foo for otherValue, then this method
/// returns true.
/// </summary>
/// <param name="rule">the rule to apply</param>
/// <param name="valueInItem">The value in the item</param>
public static bool Applies(Db.Rule rule
, String valueInItem
)
{
if (rule == null)
{
throw new ArgumentNullException("rule");
}
String valueInRule = rule.VariableValue;
int value = String.Compare(valueInRule, valueInItem);
switch (rule.Comparison)
{
case Db.Rule.Compare.Equal:
return(value == 0);
case Db.Rule.Compare.NotEqual:
return(value != 0);
case Db.Rule.Compare.Less:
return(value > 0);
case Db.Rule.Compare.Greater:
return(value < 0);
default:
var msg = new StringBuilder();
msg.Append("unknown rule comparison of type ");
msg.Append(rule.Comparison);
msg.Append(" in rule [");
msg.Append(rule.ToString());
msg.Append("]");
throw new Exception(msg.ToString());
}
}