public static FilterChain CreateChain(Definitions defs, CreatorCallback creator)
{
FilterChain chain = new AndChain();
if (defs != null && defs.Count > 0)
{
if (!defs.Any(f => f.Operation == Operations.Or))
{
// Simple AND chain
defs.ForEach(def => chain.Add(creator(def)));
}
else
{
// Mixed chain
Definition prev = defs[0];
Definition curr;
FilterChain or = new OrChain();
for (int index = 1; index < defs.Count; ++index)
{
curr = defs[index];
if (curr.Operation == Operations.Or && prev.Operation == Operations.Or)
{
// Add another "or"
or.Add(creator(prev));
}
else
{
if (or.Count != 0)
{
// End current "or" and create new chain
or.Add(creator(prev));
chain.Add(or);
or = new OrChain();
}
else
{
// Add single filter
chain.Add(creator(prev));
}
}
prev = curr;
}
// Add last pending
if (prev.Operation == Operations.Or)
{
or.Add(creator(prev));
}
if (or.Count > 0)
{
chain.Add(or);
}
if (prev.Operation == Operations.And)
{
chain.Add(creator(prev));
}
}
}
return(chain);
}
