/*
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html.
 *
 * This file is a derivative of code released under the terms listed below.
 *
 */
/*
 *
 * 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 com.ibm.wala.classLoader.IClass;
import com.ibm.wala.classLoader.IMethod;
import com.ibm.wala.ipa.cha.IClassHierarchy;
import com.ibm.wala.types.ClassLoaderReference;
import com.ibm.wala.types.Descriptor;
import com.ibm.wala.types.MethodReference;
import com.ibm.wala.types.TypeReference;
import com.ibm.wala.util.collections.HashSetFactory;
import com.ibm.wala.util.strings.Atom;
import java.io.UTFDataFormatException;
import java.util.Collection;
import java.util.LinkedList;
import java.util.Set;

public class MethodNamePattern {
  private final String className;

  private final String memberName;

  private final String descriptor; // null = match any types

  public MethodNamePattern(String c, String m, String d) {
    className = c;
    memberName = m;
    descriptor = d;
  }

  public MethodNamePattern(String c, String m) {
    className = c;
    memberName = m;
    descriptor = null;
  }

  private Collection<IMethod> lookupMethods(IClass c) {
    Collection<IMethod> matching = new LinkedList<>();
    Atom atom = Atom.findOrCreateUnicodeAtom(memberName);
    Descriptor desc = descriptor == null ? null : Descriptor.findOrCreateUTF8(descriptor);
    Collection<? extends IMethod> allMethods = c.getAllMethods();
    for (IMethod m : allMethods) {
      if (m.getName().equals(atom) && (desc == null || m.getDescriptor().equals(desc))) {
        matching.add(m);
      }
    }
    return matching;
  }

  /**
   * Returns a Collection of IMethods which are found in the following ClassLoaders: Application,
   * Primordial, Extension
   */
  public Collection<IMethod> getPossibleTargets(IClassHierarchy cha) {
    Collection<IMethod> matching = new LinkedList<>();
    IClass c;
    c = cha.lookupClass(TypeReference.findOrCreate(ClassLoaderReference.Application, className));
    if (c != null) matching.addAll(lookupMethods(c));
    c = cha.lookupClass(TypeReference.findOrCreate(ClassLoaderReference.Primordial, className));
    if (c != null) matching.addAll(lookupMethods(c));
    c = cha.lookupClass(TypeReference.findOrCreate(ClassLoaderReference.Extension, className));
    if (c != null) matching.addAll(lookupMethods(c));

    Set<IMethod> targets = HashSetFactory.make();
    for (IMethod im : matching) {
      targets.addAll(cha.getPossibleTargets(im.getReference()));
    }

    return targets;
  }

  @Override
  public String toString() {
    String returnString = "MethodNamePattern (Class: " + className + " - Method: " + memberName;
    if (descriptor == null) return returnString + ')';
    return returnString + " - Descriptor: " + descriptor + ')';
  }

  public String getDescriptor() {
    return String.format("%s.%s%s", className, memberName, descriptor == null ? "" : descriptor);
  }

  public String getClassName() {
    return className;
  }

  public String getMemberName() {
    return memberName;
  }

  public static MethodNamePattern patternForReference(MethodReference methodRef)
      throws UTFDataFormatException {
    String className = methodRef.getDeclaringClass().getName().toUnicodeString();
    String methodName = methodRef.getName().toUnicodeString();
    String descriptor = methodRef.getDescriptor().toUnicodeString();
    MethodNamePattern pattern = new MethodNamePattern(className, methodName, descriptor);
    return pattern;
  }
}
