/*
 * Copyright (c) 2002 - 2014 IBM Corporation.
 * All rights reserved. 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
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 */

/*
*  Copyright (c) 2013,
*      Tobias Blaschke <code@tobiasblaschke.de>
*  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 com.ibm.wala.ipa.summaries;

import com.ibm.wala.cfg.AbstractCFG;
import com.ibm.wala.classLoader.IClass;
import com.ibm.wala.classLoader.IMethod;
import com.ibm.wala.ipa.callgraph.Context;
import com.ibm.wala.ipa.callgraph.impl.Everywhere;
import com.ibm.wala.ssa.ConstantValue;
import com.ibm.wala.ssa.IR;
import com.ibm.wala.ssa.SSAInstruction;
import com.ibm.wala.ssa.SSAOptions;
import com.ibm.wala.types.MethodReference;
import com.ibm.wala.util.strings.Atom;
import java.util.Map;

/**
 * A SummarizedMethod (for synthetic functions) with variable names.
 *
 * <p>Using this class instead of a normal SummarizedMethod enables the use of human-readable
 * variable names in synthetic methods. This should not change th analysis-result but may come in
 * handy when debugging.
 *
 * @author Tobias Blaschke &lt;code@tobiasblaschke.de&gt;
 * @since 2013-11-25
 */
public class SummarizedMethodWithNames extends SummarizedMethod {

  private static final boolean DEBUG = false;

  private final MethodSummary summary;
  private final Map<Integer, Atom> localNames;

  public SummarizedMethodWithNames(
      MethodReference ref, MethodSummary summary, IClass declaringClass) {
    this(ref, summary, declaringClass, summary.getValueNames());
  }

  public SummarizedMethodWithNames(
      MethodReference ref,
      MethodSummary summary,
      IClass declaringClass,
      Map<Integer, Atom> localNames)
      throws NullPointerException {
    super(ref, summary, declaringClass);

    this.summary = summary;
    this.localNames = localNames;

    if (DEBUG) {
      System.err.println("From old MSUM");
    }
  }

  @SuppressWarnings("unused")
  public SummarizedMethodWithNames(
      MethodReference ref, VolatileMethodSummary summary, IClass declaringClass)
      throws NullPointerException {
    super(ref, summary.getMethodSummary(), declaringClass);
    this.summary = summary.getMethodSummary();
    this.localNames = summary.getLocalNames();
    if (DEBUG && this.localNames.isEmpty()) {
      System.err.println("Local names are empty for " + ref);
    }
  }

  public static class SyntheticIRWithNames extends SyntheticIR {
    private final SSA2LocalMap localMap;

    public static class SyntheticSSA2LocalMap implements SSA2LocalMap {
      private final Map<Integer, Atom> localNames;

      public SyntheticSSA2LocalMap(Map<Integer, Atom> localNames) {
        this.localNames = localNames;
      }

      /** Does not respect index. */
      @Override
      public String[] getLocalNames(int index, int vn) {
        if (DEBUG) {
          System.err.printf("IR.getLocalNames(%d, %d)\n", index, vn);
        }
        if (localNames != null && localNames.containsKey(vn)) {
          return new String[] {this.localNames.get(vn).toString()};
        } else {
          return null;
        }
      }
    }

    public SyntheticIRWithNames(
        IMethod method,
        Context context,
        AbstractCFG<?, ?> cfg,
        SSAInstruction[] instructions,
        SSAOptions options,
        Map<Integer, ConstantValue> constants,
        Map<Integer, Atom> localNames)
        throws AssertionError {
      super(method, context, cfg, instructions, options, constants);
      this.localMap = new SyntheticSSA2LocalMap(localNames);
    }

    @Override
    public SSA2LocalMap getLocalMap() {
      return this.localMap;
    }
  }

  /**
   * Returns the variable name to a ssa-number.
   *
   * <p>Does not respect the value of bcIndex.
   */
  @Override
  public String getLocalVariableName(int bcIndex, int localNumber) {
    if (this.localNames.containsKey(localNumber)) {
      String name = this.localNames.get(localNumber).toString();
      if (DEBUG) {
        System.err.printf("getLocalVariableName(bc=%d, no=%d) = %s\n", bcIndex, localNumber, name);
      }
      return name;
    } else {
      if (DEBUG) {
        System.err.printf("No name for %d\n", localNumber);
      }
      return super.getLocalVariableName(bcIndex, localNumber);
    }
  }

  @Override
  public boolean hasLocalVariableTable() {
    return true;
  }

  @Override
  public IR makeIR(Context context, SSAOptions options) {
    final SSAInstruction instrs[] = getStatements(options);
    final IR ir =
        new SyntheticIRWithNames(
            this,
            Everywhere.EVERYWHERE,
            makeControlFlowGraph(instrs),
            instrs,
            options,
            summary.getConstants(),
            localNames);

    return ir;
  }
}
