/*
 * Bytecode Analysis Framework
 * Copyright (C) 2005, University of Maryland
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package edu.umd.cs.findbugs.ba.ca;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import org.apache.bcel.generic.ConstantPoolGen;
import org.apache.bcel.generic.Instruction;
import org.apache.bcel.generic.InstructionHandle;
import org.apache.bcel.generic.InvokeInstruction;

import edu.umd.cs.findbugs.ba.AbstractDataflowAnalysis;
import edu.umd.cs.findbugs.ba.BasicBlock;
import edu.umd.cs.findbugs.ba.BlockOrder;
import edu.umd.cs.findbugs.ba.CFG;
import edu.umd.cs.findbugs.ba.DataflowAnalysisException;
//import edu.umd.cs.findbugs.ba.DataflowTestDriver;
import edu.umd.cs.findbugs.ba.DepthFirstSearch;
import edu.umd.cs.findbugs.ba.Edge;
import edu.umd.cs.findbugs.ba.Location;
import edu.umd.cs.findbugs.ba.ReversePostOrder;

public class CallListAnalysis extends AbstractDataflowAnalysis<CallList> {
	private DepthFirstSearch dfs;
	//private ConstantPoolGen cpg;
	private Map<InstructionHandle, Call> callMap;

	public CallListAnalysis(CFG cfg, DepthFirstSearch dfs, ConstantPoolGen cpg) {
		this.dfs = dfs;
		//this.cpg = cpg;
		this.callMap = buildCallMap(cfg, cpg);
	}

	private static Map<InstructionHandle, Call> buildCallMap(CFG cfg, ConstantPoolGen cpg) {
		Map<InstructionHandle, Call> callMap = new HashMap<InstructionHandle, Call>();

		for (Iterator<Location> i = cfg.locationIterator(); i.hasNext();) {
			InstructionHandle handle = i.next().getHandle();
			Instruction ins = handle.getInstruction();

			if (ins instanceof InvokeInstruction) {
				InvokeInstruction inv = (InvokeInstruction) ins;
				Call call = new Call(inv.getClassName(cpg), inv.getName(cpg), inv.getSignature(cpg));
				callMap.put(handle, call);
			}
		}

		return callMap;
	}

	public void initEntryFact(CallList fact) {
		fact.clear();
	}

//	public void initResultFact(CallList fact) {
//		fact.setTop();
//	}

	public boolean isForwards() {
		return true;
	}

	public BlockOrder getBlockOrder(CFG cfg) {
		return new ReversePostOrder(cfg, dfs);
	}

	public void makeFactTop(CallList fact) {
		fact.setTop();
	}

	public boolean isTop(CallList fact) {
		return fact.isTop();
	}

	public CallList createFact() {
		return new CallList();
	}

	public boolean same(CallList a, CallList b) {
		return a.equals(b);
	}

	public void meetInto(CallList start, Edge edge, CallList result)
			throws DataflowAnalysisException {
		CallList merge = CallList.merge(start, result);
		result.copyFrom(merge);
	}

	public void copy(CallList source, CallList dest) {
		dest.copyFrom(source);
	}

	@Override
		 public void transferInstruction(
			InstructionHandle handle, BasicBlock basicBlock, CallList fact) throws DataflowAnalysisException {
		Call call = callMap.get(handle);
		if (call != null) {
			fact.add(call);
		}
	}

	@Override
		 public boolean isFactValid(CallList fact) {
		return fact.isValid();
	}

//	public static void main(String[] argv) throws Exception {
//		if (argv.length != 1) {
//			System.err.println("Usage: " + CallListAnalysis.class.getName() + " <class file>");
//			System.exit(1);
//		}
//
//		DataflowTestDriver<CallList, CallListAnalysis> driver =
//			new DataflowTestDriver<CallList, CallListAnalysis>() {
//				@Override
//								 public Dataflow<CallList, CallListAnalysis> createDataflow(
//						ClassContext classContext,
//						Method method) throws CFGBuilderException, DataflowAnalysisException {
//					CallListAnalysis analysis = new CallListAnalysis(
//							classContext.getCFG(method),
//							classContext.getDepthFirstSearch(method),
//							classContext.getConstantPoolGen());
//					Dataflow<CallList, CallListAnalysis> dataflow =
//						new Dataflow<CallList, CallListAnalysis>(analysis.cfg, analysis);
//
//					dataflow.execute();
//
//					return dataflow;
//				}
//			};
//
//		driver.execute(argv[0]);	
//	}
}