// Copyright 2014 The Bazel Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//    http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package com.google.devtools.build.lib.syntax;

import java.io.IOException;

/** Syntax node for an augmented assignment statement. */
// TODO(adonovan): merge with AssignmentStatement.
public final class AugmentedAssignmentStatement extends Statement {

  private final Expression lhs; // same constraint as AssignmentStatement
  private final TokenKind op;
  private final Expression rhs;

  /** Constructs an augmented assignment. */
  public AugmentedAssignmentStatement(TokenKind op, Expression lhs, Expression rhs) {
    this.lhs = lhs;
    this.op = op;
    this.rhs = rhs;
  }

  /** Returns the operator of the assignment. */
  public TokenKind getOperator() {
    return op;
  }

  /** Returns the LHS of the assignment. */
  public Expression getLHS() {
    return lhs;
  }

  /** Returns the RHS of the assignment. */
  public Expression getRHS() {
    return rhs;
  }

  @Override
  public void prettyPrint(Appendable buffer, int indentLevel) throws IOException {
    printIndent(buffer, indentLevel);
    lhs.prettyPrint(buffer);
    buffer.append(' ');
    buffer.append(op.toString());
    buffer.append("= ");
    rhs.prettyPrint(buffer);
    buffer.append('\n');
  }

  @Override
  public void accept(SyntaxTreeVisitor visitor) {
    visitor.visit(this);
  }

  @Override
  public Kind kind() {
    return Kind.AUGMENTED_ASSIGNMENT;
  }
}