// CTGsubgraph.beh
// created: Binoy : 1998/2/11
// modified - binoy : June 10 '98

/**
Uses the tg package(from Doug) to compute the subgraph.
*/
UGraph{

	traversal toUEdgeVertex(TGCreateVisitor tg){
		to {UConstEdge, UAltEdge, UExtendEdge, UImplEdge , UVertex};
	}

	/**
	computes the subgraph
	input - StrategyGraph object
	output - true/false if success/failure
		Marks the UGraph object with tags corresponding to the subgraph
	*/
	boolean computeSubgraph(StrategyGraph sg)
		(@
		TraversalGraph tg = new TraversalGraph();
		initialize(); //create new hashtables
		hashinit(get_idToVertexTable(),get_idToEdgeTable()); //fill 'em 
		makeTgGraph(tg);
		if(!markSubgraph(sg,tg))
			return false;
		updateUGraph();
		return true;
		@)

	void makeTgGraph(TraversalGraph g) = toUEdgeVertex(TGCreateVisitor);

	boolean markSubgraph(StrategyGraph sg, TraversalGraph tg) 
		(@
		tg.makeCopies(sg.size());
		tg.addIntercopyEdges(sg);
		sg.markReachableForwardFromSources(tg);
		sg.markReachableBackwardFromTargets(tg);
		if (!sg.allSourcesAndTargetsMarked(tg)) {
			System.err.println("Error: No path found.");
			return false;
		}
		return true;
		@)

	void updateUGraph() = toVertEdge(TGUpdateVisitor);

}

TGCreateVisitor{

	before UGraph
		(@
		vtable = host.get_idToVertexTable();
		@)

	before UConstEdge 
		(@ 
		TGEdge e= new TGCEdge();
		UID uidSrc = host.get_fromVertex();
		UID uidDest = host.get_toVertex();
		UVertex vsrc = (UVertex)vtable.get(uidSrc);
		UVertex vdest = (UVertex)vtable.get(uidDest);
		//System.out.println("debug 1 " + vsrc.get_vertexname().get_name() + vdest.get_vertexname().get_name() );
		ClassName csrc = new ClassName(vsrc.get_vertexname().get_name());
		ClassName cdest = new ClassName(vdest.get_vertexname().get_name());
		//System.out.println("debug 2");
		TGVertex s = g.findVertex(csrc, true);	//e.source
						//(adds it if not already there)
		TGVertex d = g.findVertex(cdest,true);	//e.dest
		e.set_source(s); 
		e.set_dest(d); 
		//System.out.println("debug 2");
		if(host.get_edgename() != null)
			((TGCEdge)e).set_name(new PartName(host.get_edgename().get_name()));			//(set name for const edge)
		else
			((TGCEdge)e).set_name(new PartName(new Ident("_")));
		//System.out.println("debug 3");
		g.addEdge(e);
		vsrc.set_tgv(s);
		vdest.set_tgv(d);
		//System.out.println("debug 4");
		host.set_tge((TGCEdge)e);
		//System.out.println("debug ");

		@)

	before {UAltEdge,UExtendEdge }
		(@ 
		TGEdge e= new TGAEdge();

		UID uidSrc = host.get_fromVertex();
		UID uidDest = host.get_toVertex();
		UVertex vsrc = (UVertex)vtable.get(uidSrc);
		UVertex vdest = (UVertex)vtable.get(uidDest);
		ClassName csrc = new ClassName(vsrc.get_vertexname().get_name());
		ClassName cdest = new ClassName(vdest.get_vertexname().get_name());
		TGVertex d = g.findVertex(csrc, true);	//e.dest
						//(adds it if not already there)
		TGVertex s = g.findVertex(cdest,true);	//e.source
		e.set_source(s);
		e.set_dest(d); 
		g.addEdge(e);
		vsrc.set_tgv(s);
		vdest.set_tgv(d);
		host.set_tge((TGAEdge)e);
		@)

	before UImplEdge 
		(@ 
		TGEdge e= new TGIEdge();

		UID uidSrc = host.get_fromVertex();
		UID uidDest = host.get_toVertex();
		UVertex vsrc = (UVertex)vtable.get(uidSrc);
		UVertex vdest = (UVertex)vtable.get(uidDest);
		ClassName csrc = new ClassName(vsrc.get_vertexname().get_name());
		ClassName cdest = new ClassName(vdest.get_vertexname().get_name());
		TGVertex s = g.findVertex(csrc, true);	//e.source
						//(adds it if not already there)
		TGVertex d = g.findVertex(cdest,true);	//e.dest
		e.set_source(s);	//if error when apstudio implements this, 
		e.set_dest(d);		//interchange (s)rc & (d)est 
		g.addEdge(e);
		vsrc.set_tgv(s);
		vdest.set_tgv(d);
		host.set_tge((TGIEdge)e);
		@)

	before UVertex
		(@
		//want to prevent the possibility that there is a UVertex thats
		//not associated with any UEdge, and hence doesnt 
		//get the <tgv> initialised
		ClassName cthis = new ClassName(host.get_vertexname().get_name());
		TGVertex s = g.findVertex(cthis , true);
		host.set_tgv(s);
		@)

}

TGUpdateVisitor{

	before UVertex
		(@
//		System.out.println("debug 1");
		if(host.get_vdeco() == null){
//			System.out.println("debug 1a");
			host.set_vdeco(new Decorator());
//			System.out.println("debug 1b");
		}
		if(host.get_tgv() == null)
			System.out.println("how come no tgv for - " + host.get_vertexname().get_name());
		if(host.get_tgv().is_in_trav()){
//			System.out.println("debug 2");
			host.get_vdeco().setMarked(3);//host.set tag
		}
		else{
//			System.out.println("debug 3");
			host.get_vdeco().setMarked(0);//host.reset tag
		}
//		System.out.println("debug 4");
		host.set_tgv(null);
		@)

	before UConstEdge
		(@
		if(host.get_edeco() == null)
			host.set_edeco(new Decorator());
		if(host.get_tge().is_in_trav()){
			host.get_edeco().setMarked(3);//host.set tag
		}
		else
			host.get_edeco().setMarked(0);//host.reset tag
		host.set_tge(null);
		@)
	before {UAltEdge,UExtendEdge}
		(@
		if(host.get_edeco() == null)
			host.set_edeco(new Decorator());
		if(host.get_tge().is_in_trav()){
			host.get_edeco().setMarked(3);//host.set tag
		}
		else
			host.get_edeco().setMarked(0);//host.reset tag
		host.set_tge(null);
		@)
	before UImplEdge
		(@
		if(host.get_edeco() == null)
			host.set_edeco(new Decorator());
		if(host.get_tge().is_in_trav()){
			host.get_edeco().setMarked(3);//host.set tag
		}
		else
			host.get_edeco().setMarked(0);//host.reset tag
		host.set_tge(null);
		@)

}