package org.checkerframework.dataflow.cfg.node;

import com.sun.source.tree.BinaryTree;
import com.sun.source.tree.Tree;
import com.sun.source.tree.Tree.Kind;
import java.util.Objects;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A node for the less than comparison:
 *
 * <pre>
 *   <em>expression</em> &lt; <em>expression</em>
 * </pre>
 *
 * We allow less than nodes without corresponding AST {@link Tree}s.
 */
public class LessThanNode extends BinaryOperationNode {

  public LessThanNode(BinaryTree tree, Node left, Node right) {
    super(tree, left, right);
    assert tree.getKind() == Kind.LESS_THAN;
  }

  @Override
  public <R, P> R accept(NodeVisitor<R, P> visitor, P p) {
    return visitor.visitLessThan(this, p);
  }

  @Override
  public String toString() {
    return "(" + getLeftOperand() + " < " + getRightOperand() + ")";
  }

  @Override
  public boolean equals(@Nullable Object obj) {
    if (!(obj instanceof LessThanNode)) {
      return false;
    }
    LessThanNode other = (LessThanNode) obj;
    return getLeftOperand().equals(other.getLeftOperand())
        && getRightOperand().equals(other.getRightOperand());
  }

  @Override
  public int hashCode() {
    return Objects.hash(getLeftOperand(), getRightOperand());
  }
}