rule RootElement {
	from
		s : A!Product
	to
		t : B!BCModel	(
			        -- add a category and pass all references to its rule
					categories <- thisModule.addArmature(s.references.asOrderedSet())
	)
}

lazy rule addArmature{
	from 
		s : OrderedSet(A!PartReference)
	to 	
		t : B!Category(
			name <- 'Armature',
			-- here we add distributors with a helper 
			-- to avoid adding distributors with same name twice
			distributors <- thisModule.fetchDistributors(s)
			)
}

lazy rule addDistri{
	from 
		s : A!PartReference
	to 	
		t : B!Distributor( 
			name <- s.part.distributor,
			blocks <- thisModule.addBlock(s)
	)
}

lazy rule addBlock{
	from 
		s : A!PartReference
	to 	
		t : B!PartBlock( 
			name <- s.part.name,
			price <- s.part.cost * s.amount -- calc proper price
	)
}

helper def : fetchDistributors(refs : OrderedSet(A!PartReference)) : OrderedSet(B!Distributor) =
	refs->iterate(e ; retValue : OrderedSet(B!Distributor) = OrderedSet{} | 
			if e.part = OclUndefined 
				then retValue 
			else 
				if e.part.distributorExists(retValue).oclIsTypeOf(B!Distributor) = false
					then retValue.append(thisModule.addDistri(e)) 
				else 
					-- how to catch the existing distributor 
					-- and add a Partblock(how its done in addBlock rule) 
					-- with information of the iterator ???
					retValue
				endif
			endif
		);
		
-- this helper return OclUndefined if distributor does not exist, else the distributor instance
helper context A!Part def: distributorExists(distris : OrderedSet(B!Distributor)) : B!Distributor =
			distris->iterate(e; retValue : B!Distributor = OclUndefined |
			if e.name = self.distributor
				then e
			else
				retValue
				endif);