public override void PerformOnWhen(CaseExpression node)
{
if (node == null)
{
throw new ArgumentNullException("node");
}
m_sql.Append(NewLine);
}
SwitchFunction MakeSwitch(CaseExpression caseExpr)
{
if (caseExpr == null)
{
throw new ArgumentNullException("caseExpr");
}
IExpression left = caseExpr.Case;
SwitchFunction switchFunc = new SwitchFunction();
CaseAlternative alt = caseExpr.Alternatives;
if (alt == null)
{
throw new InvalidOperationException("CASE has no alternatives.");
}
// branch expressions will be tailored through caseExpr.Alternatives
if (left != null)
{
while (alt != null)
{
alt.When = new Expression(left.Clone(), ExpressionOperator.Equal,
alt.When);
CaseAlternative next = alt.Next;
alt.Next = null;
switchFunc.Add(alt);
alt = next;
}
}
else
{
switchFunc.Alternatives = alt;
}
IExpression elseExpr = caseExpr.Else;
if (elseExpr != null)
{
// elseExpr will be tailored through caseExpr.Else
CaseAlternative last = new CaseAlternative(
new Expression(
new IntegerValue(1),
ExpressionOperator.Equal,
new IntegerValue(1)),
elseExpr);
switchFunc.Add(last);
}
return(switchFunc);
}
public override void PerformBefore(CaseExpression node)
{
if (node == null)
{
throw new ArgumentNullException("node");
}
ReplaceTerm(node, MakeSwitch(node));
base.PerformBefore(node);
}
public override void PerformOnElse(CaseExpression node)
{
if (node == null)
{
throw new ArgumentNullException("node");
}
if (node.Else != null)
{
m_sql.Append("ELSE ");
}
}
public override void PerformBefore(CaseExpression node)
{
if (node == null)
{
throw new ArgumentNullException("node");
}
m_sql.Append("CASE");
if (node.Case != null)
{
m_sql.Append(' ');
}
}
public override void PerformAfter(CaseExpression node)
{
if (node == null)
{
throw new ArgumentNullException("node");
}
if (node.Else != null)
{
m_sql.Append(NewLine);
}
m_sql.Append("END");
}
public INode Clone()
{
CaseExpression caseExpression = new CaseExpression();
if (m_case != null)
{
caseExpression.Case = (IExpression)(m_case.Clone());
}
if (m_else != null)
{
caseExpression.Else = (IExpression)(m_else.Clone());
}
if (m_alternatives != null)
{
caseExpression.Alternatives = (CaseAlternative)(m_alternatives.Clone());
}
return(caseExpression);
}
public virtual void PerformAfter(CaseExpression node)
{
}
public virtual void PerformOnElse(CaseExpression node)
{
}
public virtual void PerformOnWhen(CaseExpression node)
{
}
public virtual void PerformBefore(CaseExpression node)
{
}
INode MakeSubstring(FunctionCall substringCall)
{
if (substringCall == null)
{
throw new ArgumentNullException("substringCall");
}
if (TailorUtil.HasNullArgument(substringCall))
{
return(NullValue.Value);
}
ExpressionItem val = substringCall.ExpressionArguments;
if (val == null)
{
throw new InvalidOperationException("No parameters for SUBSTRING.");
}
ExpressionItem start = val.Next;
if (start == null)
{
throw new InvalidOperationException("Too few parameters for SUBSTRING.");
}
ExpressionItem len = start.Next;
// before adding len to the list
Expression when = MakeNotNullCheck(substringCall.ExpressionArguments);
if (len == null)
{
IExpression argument = TailorUtil.MakeLenArg(start.Expression,
val.Expression, "LEN");
start.Add(new ExpressionItem(argument));
}
else
{
if (len.Next != null)
{
throw new InvalidOperationException("Too many parameters for SUBSTRING.");
}
}
if (when != null)
{
CaseExpression caseExpression = new CaseExpression();
caseExpression.Alternatives = new CaseAlternative(when, substringCall);
Expression elseExpr = new Expression();
elseExpr.Left = NullValue.Value;
caseExpression.Else = elseExpr;
return(caseExpression);
}
else
{
return(substringCall);
}
}
public override void PerformAfter(CaseExpression node)
{
PopKnownParent(node);
}
public override void PerformBefore(CaseExpression node)
{
PushParent(node);
}