content: /*
   * [The "BSD licence"]
   * Copyright (c) 2010 Ben Gruver (JesusFreke)
   * 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 name of the author may not be used to endorse or promote products
   *    derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.jf.dexlib.Code.Format;
  
  import org.jf.dexlib.Code.Instruction;
  import org.jf.dexlib.Code.MultiOffsetInstruction;
  import org.jf.dexlib.Code.Opcode;
  import org.jf.dexlib.DexFile;
  import org.jf.dexlib.Util.AnnotatedOutput;
  import org.jf.dexlib.Util.NumberUtils;
  
  import java.util.Iterator;
  
  public class SparseSwitchDataPseudoInstruction extends Instruction implements MultiOffsetInstruction {
      public static final Instruction.InstructionFactory Factory = new Factory();
      private int[] keys;
      private int[] targets;
  
      @Override
      public int getSize(int codeAddress) {
          return getTargetCount() * 4 + 2 + (codeAddress % 2);
      }
  
      public SparseSwitchDataPseudoInstruction(int[] keys, int[] targets) {
          super(Opcode.NOP);
  
          if (keys.length != targets.length) {
              throw new RuntimeException("The number of keys and targets don't match");
          }
  
          if (targets.length == 0) {
              throw new RuntimeException("The sparse-switch data must contain at least 1 key/target");
          }
  
          if (targets.length > 0xFFFF) {
              throw new RuntimeException("The sparse-switch data contains too many elements. " +
                      "The maximum number of switch elements is 65535");
          }
  
          this.keys = keys;
          this.targets = targets;
      }
  
      public SparseSwitchDataPseudoInstruction(byte[] buffer, int bufferIndex) {
          super(Opcode.NOP);
  
          byte opcodeByte = buffer[bufferIndex];
          if (opcodeByte != 0x00) {
              throw new RuntimeException("Invalid opcode byte for a SparseSwitchData pseudo-instruction");
          }
          byte subopcodeByte = buffer[bufferIndex+1];
          if (subopcodeByte != 0x02) {
              throw new RuntimeException("Invalid sub-opcode byte for a SparseSwitchData pseudo-instruction");
          }
  
          int targetCount = NumberUtils.decodeUnsignedShort(buffer, bufferIndex + 2);
          keys = new int[targetCount];
          targets = new int[targetCount];
  
          for (int i=0; i<targetCount; i++) {
              keys[i] = NumberUtils.decodeInt(buffer, bufferIndex + 4 + i*4);
              targets[i] = NumberUtils.decodeInt(buffer, bufferIndex + 4 + targetCount*4 + i*4);
          }
      }
  
      protected void writeInstruction(AnnotatedOutput out, int currentCodeAddress) {
          out.alignTo(4);
  
          out.writeByte(0x00);
          out.writeByte(0x02);
          out.writeShort(targets.length);
  
          if (targets.length > 0) {
              int key = keys[0];
  
              out.writeInt(key);
  
              for (int i = 1; i < keys.length; i++) {
                  key = keys[i];
                  assert key >= keys[i - 1];
                  out.writeInt(key);
              }
  
              for (int target : targets) {
                  out.writeInt(target);
              }
          }
      }
  
      protected void annotateInstruction(AnnotatedOutput out, int currentCodeAddress) {
          out.annotate(getSize(currentCodeAddress)*2, "[0x" + Integer.toHexString(currentCodeAddress) + "] " +
                  "sparse-switch-data instruction");
      }
  
      public void updateTarget(int targetIndex, int targetAddressOffset) {
          targets[targetIndex] = targetAddressOffset;
      }
  
      public Format getFormat() {
          return Format.SparseSwitchData;
      }
  
      public int getTargetCount() {
          return targets.length;
      }
  
      public int[] getTargets() {
          return targets;
      }
  
      public int[] getKeys() {
          return keys;
      }
  
      public static class SparseSwitchTarget {
          public int key;
          public int targetAddressOffset;
      }
  
      public Iterator<SparseSwitchTarget> iterateKeysAndTargets() {
          return new Iterator<SparseSwitchTarget>() {
              final int targetCount = getTargetCount();
              int i = 0;
  
              SparseSwitchTarget sparseSwitchTarget = new SparseSwitchTarget();
  
              public boolean hasNext() {
                  return i<targetCount;
              }
  
              public SparseSwitchTarget next() {
                  sparseSwitchTarget.key = keys[i];
                  sparseSwitchTarget.targetAddressOffset = targets[i];
                  i++;
                  return sparseSwitchTarget;
              }
  
              public void remove() {
              }
          };
      }
  
      private static class Factory implements Instruction.InstructionFactory {
          public Instruction makeInstruction(DexFile dexFile, Opcode opcode, byte[] buffer, int bufferIndex) {
              if (opcode != Opcode.NOP) {
                  throw new RuntimeException("The opcode for a SparseSwitchDataPseudoInstruction must be NOP");
              }
              return new SparseSwitchDataPseudoInstruction(buffer, bufferIndex);
          }
      }
  }
  