/*
 *
 * Copyright (c) 2009-2012,
 *
 *  Galois, Inc. (Aaron Tomb <atomb@galois.com>)
 *  Steve Suh           <suhsteve@gmail.com>
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * 3. The names of the contributors may not be used to endorse or promote
 * products derived from this software without specific prior written
 * permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 *
 */

package org.scandroid.spec;

import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.scandroid.domain.CodeElement;
import org.scandroid.domain.InstanceKeyElement;
import org.scandroid.flow.InflowAnalysis;
import org.scandroid.flow.types.FlowType;
import org.scandroid.flow.types.ParameterFlow;
import org.scandroid.util.CGAnalysisContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.collect.Lists;
import com.ibm.wala.classLoader.IClass;
import com.ibm.wala.classLoader.IMethod;
import com.ibm.wala.dataflow.IFDS.ISupergraph;
import com.ibm.wala.ipa.callgraph.CGNode;
import com.ibm.wala.ipa.callgraph.CallGraph;
import com.ibm.wala.ipa.callgraph.propagation.ConcreteTypeKey;
import com.ibm.wala.ipa.callgraph.propagation.InstanceKey;
import com.ibm.wala.ipa.callgraph.propagation.PointerAnalysis;
import com.ibm.wala.ipa.callgraph.propagation.PointerKey;
import com.ibm.wala.ipa.cfg.BasicBlockInContext;
import com.ibm.wala.ssa.ISSABasicBlock;
import com.ibm.wala.ssa.SSAInvokeInstruction;
import com.ibm.wala.types.TypeReference;
import com.ibm.wala.util.intset.OrdinalSet;


/**
 * Entry arg source specs represent sources that are arguments to methods 
 * that are entry points.
 * 
 * For example, the command line arguments to a {@code main(String[] args)}
 * are entry arg sources.
 * 
 */
public class EntryArgSourceSpec extends SourceSpec {
	private static final Logger logger = LoggerFactory.getLogger(EntryArgSourceSpec.class);
	
	public EntryArgSourceSpec(MethodNamePattern name, int[] args) {
        namePattern = name;
        argNums = args;
    }    
	@Override
	public<E extends ISSABasicBlock> void addDomainElements(CGAnalysisContext<E> ctx,
			Map<BasicBlockInContext<E>, Map<FlowType<E>, Set<CodeElement>>> taintMap,
			IMethod im, BasicBlockInContext<E> block, SSAInvokeInstruction invInst,
			int[] newArgNums, 
			ISupergraph<BasicBlockInContext<E>, CGNode> graph, PointerAnalysis pa, CallGraph cg) {

		for(CGNode node: cg.getNodes(im.getReference())) {
		    for(int i: newArgNums) {
		        FlowType<E> flow = new ParameterFlow<E>(block, i, true);
		        final int ssaVal = node.getIR().getParameter(i);
				final Set<CodeElement> valueElements = CodeElement.valueElements(pa, node, ssaVal);
				
				PointerKey pk = pa.getHeapModel().getPointerKeyForLocal(node, ssaVal);
				final OrdinalSet<InstanceKey> pointsToSet = pa.getPointsToSet(pk);
				
				if (pointsToSet.isEmpty()) {
					TypeReference typeRef = node.getMethod().getParameterType(i);
					IClass clazz = node.getMethod().getClassHierarchy().lookupClass(typeRef);
					if (null == clazz) {
						logger.error("couldn't find entry arg class {}", typeRef);
					} else if (clazz.isInterface()) {						
						for (IClass impl : pa.getClassHierarchy().getImplementors(typeRef)) {
							logger.debug("creating instance key {} for interface {}", impl, clazz);
							InstanceKey ik = new ConcreteTypeKey(impl);
							valueElements.addAll(ctx.codeElementsForInstanceKey(ik));
						}
					} else {
						InstanceKey ik = new ConcreteTypeKey(clazz);
						valueElements.addAll(ctx.codeElementsForInstanceKey(ik));
					}					
				}
				
				for (InstanceKey ik : pointsToSet) {
					valueElements.addAll(ctx.codeElementsForInstanceKey(ik));
				}
				InflowAnalysis.addDomainElements(taintMap, block, flow, valueElements);
				logger.debug("added elements for entry {}: {}", this, valueElements);
		    }
		}
	}
	
	@Override
	public String toString() {
		return String.format("EntryArgSourceSpec(%s, %s)", namePattern, Arrays.toString(argNums));
	}
}
