/**
 * Copyright (C) 2010-2017 Gordon Fraser, Andrea Arcuri and EvoSuite
 * contributors
 *
 * This file is part of EvoSuite.
 *
 * EvoSuite 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 3.0 of the License, or
 * (at your option) any later version.
 *
 * EvoSuite 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 Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with EvoSuite. If not, see <http://www.gnu.org/licenses/>.
 */
package org.evosuite.graphs.ccg;

import java.util.List;
import java.util.Map;

import org.evosuite.graphs.EvoSuiteGraph;
import org.evosuite.graphs.GraphPool;
import org.evosuite.graphs.cfg.BytecodeInstruction;
import org.evosuite.graphs.cfg.RawControlFlowGraph;

/**
 * Represents the method call structure of a class in a graph.
 * 
 * The graph contains a node for each of the classes methods with edges going
 * from a method node to each of its called methods.
 * 
 * Edges are labeled with the BytecodeInstruction of the corresponding call.
 * 
 * @author Andre Mis
 */
public class ClassCallGraph extends EvoSuiteGraph<ClassCallNode, ClassCallEdge> {

	private final String className;

	private final ClassLoader classLoader;

	/**
	 * @return the classLoader
	 */
	public ClassLoader getClassLoader() {
		return classLoader;
	}

	/**
	 * <p>
	 * Constructor for ClassCallGraph.
	 * </p>
	 * 
	 * @param className
	 *            a {@link java.lang.String} object.
	 */
	public ClassCallGraph(ClassLoader classLoader, String className) {
		super(ClassCallEdge.class);

		this.className = className;
		this.classLoader = classLoader;

		compute();
	}

	private void compute() {
		Map<String, RawControlFlowGraph> cfgs = GraphPool.getInstance(classLoader).getRawCFGs(className);

		if (cfgs == null)
			throw new IllegalStateException(
			        "did not find CFGs for a class I was supposed to compute the CCG of");

		// add nodes
		for (String method : cfgs.keySet())
			addVertex(new ClassCallNode(method));

		//		System.out.println("generating class call graph for "+className);

		// add vertices
		for (ClassCallNode methodNode : graph.vertexSet()) {
			RawControlFlowGraph rcfg = cfgs.get(methodNode.getMethod());
			List<BytecodeInstruction> calls = rcfg.determineMethodCallsToOwnClass();
			//			System.out.println(calls.size()+" method calls from "+methodNode);
			for (BytecodeInstruction call : calls) {
				//				System.out.println("  to "+call.getCalledMethod()+" in "+call.getCalledMethodsClass());
				ClassCallNode calledMethod = getNodeByMethodName(call.getCalledMethod());
				if (calledMethod != null) {
					ClassCallEdge e = new ClassCallEdge(call);
					addEdge(methodNode, calledMethod, e);
				}
			}
		}
	}

	/**
	 * <p>
	 * getNodeByMethodName
	 * </p>
	 * 
	 * @param methodName
	 *            a {@link java.lang.String} object.
	 * @return a {@link org.evosuite.graphs.ccg.ClassCallNode} object.
	 */
	public ClassCallNode getNodeByMethodName(String methodName) {
		ClassCallNode r = null;
		//		System.out.println("getting node by methodName "+methodName);
		for (ClassCallNode node : graph.vertexSet()) {
			if (node.getMethod().equals(methodName)) {
				if (r == null) {
					r = node;
				} else {
					throw new IllegalStateException(
					        "Expect each ClassCallNode to have a unique method name");
				}
			}
		}
		// TODO logger.warn
		//		if(r==null)
		//			System.out.println("didn't find node by methodName "+methodName);
		return r;
	}

	/**
	 * <p>
	 * Getter for the field <code>className</code>.
	 * </p>
	 * 
	 * @return a {@link java.lang.String} object.
	 */
	public String getClassName() {
		return className;
	}

	// toDot util

	/** {@inheritDoc} */
	@Override
	public String getName() {
		return "CCG_" + className;
	}

	/** {@inheritDoc} */
	@Override
	protected String dotSubFolder() {
		return toFileString(className) + "/";
	}
}