/*
 * 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,
 *
 *  Adam Fuchs          <afuchs@cs.umd.edu>
 *  Avik Chaudhuri      <avik@cs.umd.edu>
 *
 * 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.domain;

import com.ibm.wala.dataflow.IFDS.PathEdge;
import com.ibm.wala.dataflow.IFDS.TabulationDomain;
import com.ibm.wala.ipa.cfg.BasicBlockInContext;
import com.ibm.wala.ssa.ISSABasicBlock;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.stream.Stream;

public class IFDSTaintDomain<E extends ISSABasicBlock>
    implements TabulationDomain<DomainElement, BasicBlockInContext<E>> {
  private final Map<DomainElement, Integer> table = new HashMap<>();
  private final ArrayList<DomainElement> objects = new ArrayList<>();

  private final Map<CodeElement, Set<DomainElement>> elementIndex = new HashMap<>();

  Set<DomainElement> emptySet = new HashSet<>();

  public Set<DomainElement> getPossibleElements(CodeElement codeElement) {
    Set<DomainElement> elts = elementIndex.get(codeElement);
    if (elts != null) return elts;
    return emptySet;
  }

  private void index(DomainElement e) {
    Set<DomainElement> elements = elementIndex.computeIfAbsent(e.codeElement, k -> new HashSet<>());
    elements.add(e);
  }

  @Override
  public int add(DomainElement o) {
    Integer i = table.get(o);
    if (i == null) {
      objects.add(o);
      i = table.size() + 1;
      table.put(o, i);
      // System.out.println("Adding domain element "+i+": "+o);
    }
    index(o);

    return i;
  }

  @Override
  public synchronized int getMappedIndex(final Object o) {
    if (!(o instanceof DomainElement)) {
      throw new IllegalArgumentException(o.getClass().getCanonicalName());
    }

    final DomainElement de = (DomainElement) o;
    final Integer i = table.get(de);

    return (i == null ? add(de) : i);
  }

  @Override
  public boolean hasPriorityOver(
      PathEdge<BasicBlockInContext<E>> p1, PathEdge<BasicBlockInContext<E>> p2) {
    return false;
  }

  @Override
  public DomainElement getMappedObject(int n) {
    if (n > 0 && n <= objects.size()) return objects.get(n - 1);
    return null;
  }

  @Override
  public int getMaximumIndex() {
    return objects.size();
  }

  @Override
  public int getSize() {
    return objects.size() + 1;
  }

  @Override
  public boolean hasMappedIndex(DomainElement o) {
    return table.containsKey(o);
  }

  @Override
  public Iterator<DomainElement> iterator() {
    return table.keySet().iterator();
  }

  @Override
  public Stream<DomainElement> stream() {
    return objects.stream();
  }

  public Set<CodeElement> codeElements() {
    return elementIndex.keySet();
  }
}
