// Copyright (c) 2016, the R8 project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
package com.android.tools.r8.code;

import com.android.tools.r8.dex.Constants;
import com.android.tools.r8.dex.IndexedItemCollection;
import com.android.tools.r8.graph.GraphLens;
import com.android.tools.r8.graph.ObjectToOffsetMapping;
import com.android.tools.r8.graph.ProgramMethod;
import com.android.tools.r8.ir.conversion.LensCodeRewriterUtils;
import com.android.tools.r8.naming.ClassNameMapper;
import com.android.tools.r8.utils.structural.CompareToVisitor;
import com.android.tools.r8.utils.structural.StructuralSpecification;
import java.nio.ShortBuffer;

abstract class Format12x extends Base1Format {

  public final byte A, B;

  private static void specify(StructuralSpecification<Format12x, ?> spec) {
    spec.withInt(i -> i.A).withInt(i -> i.B);
  }

  // vB | vA | op
  Format12x(int high, BytecodeStream stream) {
    super(stream);
    A = (byte) (high & 0xF);
    B = (byte) ((high >> 4) & 0xF);
  }

  Format12x(int A, int B) {
    assert 0 <= A && A <= Constants.U4BIT_MAX;
    assert 0 <= B && B <= Constants.U4BIT_MAX;
    this.A = (byte) A;
    this.B = (byte) B;
  }

  @Override
  public void write(
      ShortBuffer dest,
      ProgramMethod context,
      GraphLens graphLens,
      ObjectToOffsetMapping mapping,
      LensCodeRewriterUtils rewriter) {
    writeFirst(B, A, dest);
  }

  @Override
  public final int hashCode() {
    return ((A << 4) | B) ^ getClass().hashCode();
  }

  @Override
  final int internalAcceptCompareTo(Instruction other, CompareToVisitor visitor) {
    return visitor.visit(this, (Format12x) other, Format12x::specify);
  }


  @Override
  public String toString(ClassNameMapper naming) {
    return formatString("v" + A + ", v" + B);
  }

  @Override
  public String toSmaliString(ClassNameMapper naming) {
    return formatSmaliString("v" + A + ", v" + B);
  }

  @Override
  public void collectIndexedItems(
      IndexedItemCollection indexedItems,
      ProgramMethod context,
      GraphLens graphLens,
      LensCodeRewriterUtils rewriter) {
    // No references.
  }
}