/*******************************************************************************
 * Copyright (c) 2017 Politecnico di Torino and others.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Apache License, Version 2.0
 * which accompanies this distribution, and is available at
 * http://www.apache.org/licenses/LICENSE-2.0
 *******************************************************************************/

package mcnet.netobjs;


import java.util.ArrayList;
import java.util.List;

import com.microsoft.z3.BoolExpr;
import com.microsoft.z3.Context;
import com.microsoft.z3.DatatypeExpr;
import com.microsoft.z3.Expr;
import com.microsoft.z3.FuncDecl;
import com.microsoft.z3.IntExpr;
import com.microsoft.z3.Solver;

import mcnet.components.NetContext;
import mcnet.components.Network;
import mcnet.components.NetworkObject;
/**
 * WebServer object
 *
 */
public class PolitoWebServer extends NetworkObject{

		List<BoolExpr> constraints;
		Context ctx;
		DatatypeExpr node;
		Network net;
		NetContext nctx;
		FuncDecl isInBlacklist;

		public PolitoWebServer(Context ctx, Object[]... args) {
			super(ctx, args);
		}

		@Override
		protected void init(Context ctx, Object[]... args) {
			this.ctx = ctx;
		    isEndHost=true;
	   		constraints = new ArrayList<BoolExpr>();
	        z3Node = ((NetworkObject)args[0][0]).getZ3Node();
	        node = z3Node;
	        net = (Network)args[0][1];
	        nctx = (NetContext)args[0][2];
	        webServerRules();
	    }

		@Override
		public DatatypeExpr getZ3Node() {
			return node;
		}

		@Override
		protected void addConstraints(Solver solver) {
				BoolExpr[] constr = new BoolExpr[constraints.size()];
			    solver.add(constraints.toArray(constr));
		}

	    private void webServerRules (){
	    	Expr n_0 = ctx.mkConst("webserver_"+node+"_n_0", nctx.node);
	    	Expr p_0 = ctx.mkConst("webserver_"+node+"_p_0", nctx.packet);
	    	Expr p_1 = ctx.mkConst("webserver_"+node+"_p_1", nctx.packet);
	    	IntExpr t_0 = ctx.mkIntConst("webserver_"+node+"_t_0");
	    	IntExpr t_1 = ctx.mkIntConst("webserver_"+node+"_t_1");

	    	//Constraint1		send(politoWebServer, n_0, p, t_0) -> nodeHasAddr(politoWebServer,p.src)
	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
                    ctx.mkImplies((BoolExpr)nctx.send.apply(node, n_0, p_0, t_0),
                    		(BoolExpr)nctx.nodeHasAddr.apply(node,nctx.pf.get("src").apply(p_0))),1,null,null,null,null));

	    	//Constraint2		send(politoWebServer, n_0, p, t_0) -> p.origin == politoWebServer
	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
                    ctx.mkImplies((BoolExpr)nctx.send.apply(node, n_0, p_0, t_0),
                    		ctx.mkEq(nctx.pf.get("origin").apply(p_0),node)),1,null,null,null,null));

	    	//Constraint3		send(politoWebServer, n_0, p, t_0) -> p.orig_body == p.body
	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
                    ctx.mkImplies((BoolExpr)nctx.send.apply(node, n_0, p_0, t_0),
                    		ctx.mkEq(nctx.pf.get("orig_body").apply(p_0),nctx.pf.get("body").apply(p_0))),
                    1,null,null,null,null));

	    	//Constraint4		recv(n_0, politoWebServer, p, t_0) -> nodeHasAddr(politoWebServer,p.dest)
	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
                    ctx.mkImplies((BoolExpr)nctx.recv.apply(n_0,node, p_0, t_0),
                    		(BoolExpr)nctx.nodeHasAddr.apply(node,nctx.pf.get("dest").apply(p_0))),1,null,null,null,null));

	    	//Constraint5
			//	    			send(politoWebServer, n_0, p, t_0)  ->
			//	    			(exist p_1,t_1 :
			//	    	    		(t_1 < t_0 && recv(n_0, politoWebServer, p_1, t_1) &&
			//	    	     		p_0.proto == HTTP_RESP &&  p_1.proto == HTTP_REQ &&
			//	    	     		p_0.dest == p_1.src && p_0.src == p_1.dest &&  p_0.url == p_1.url)
	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
                    ctx.mkImplies((BoolExpr)nctx.send.apply(node, n_0, p_0, t_0),
                        ctx.mkExists(new Expr[]{p_1, t_1},
                            ctx.mkAnd(
                            		ctx.mkLt(t_1, t_0),
                            		ctx.mkEq(nctx.pf.get("url").apply(p_0), nctx.pf.get("url").apply(p_1)),
                            		(BoolExpr)nctx.recv.apply(n_0, node, p_1, t_1),
                            		ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.HTTP_RESPONSE)),
                            		ctx.mkEq(nctx.pf.get("proto").apply(p_1), ctx.mkInt(nctx.HTTP_REQUEST)),
                            		ctx.mkEq(nctx.pf.get("dest").apply(p_0), nctx.pf.get("src").apply(p_1)),
                            		ctx.mkEq(nctx.pf.get("src").apply(p_0), nctx.pf.get("dest").apply(p_1))),
                            1,null,null,null,null)),1,null,null,null,null));
	    }
}