package org.checkerframework.dataflow.cfg.node;

import com.sun.source.tree.SynchronizedTree;
import java.util.Collection;
import java.util.Collections;
import java.util.Objects;
import javax.lang.model.type.TypeKind;
import javax.lang.model.util.Types;
import org.checkerframework.checker.nullness.qual.Nullable;
import org.checkerframework.dataflow.qual.SideEffectFree;

/**
 * This represents the start and end of a synchronized code block. If startOfBlock == true it is the
 * node preceding a synchronized code block. Otherwise it is the node immediately after a
 * synchronized code block.
 */
public class SynchronizedNode extends Node {

  protected final SynchronizedTree tree;
  protected final Node expression;
  protected final boolean startOfBlock;

  public SynchronizedNode(
      SynchronizedTree tree, Node expression, boolean startOfBlock, Types types) {
    super(types.getNoType(TypeKind.NONE));
    this.tree = tree;
    this.expression = expression;
    this.startOfBlock = startOfBlock;
  }

  @Override
  public SynchronizedTree getTree() {
    return tree;
  }

  public Node getExpression() {
    return expression;
  }

  public boolean getIsStartOfBlock() {
    return startOfBlock;
  }

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

  @Override
  public String toString() {
    StringBuilder sb = new StringBuilder();
    sb.append("synchronized (");
    sb.append(expression);
    sb.append(")");
    return sb.toString();
  }

  @Override
  public boolean equals(@Nullable Object obj) {
    if (!(obj instanceof SynchronizedNode)) {
      return false;
    }
    SynchronizedNode other = (SynchronizedNode) obj;
    return Objects.equals(getTree(), other.getTree())
        && getExpression().equals(other.getExpression())
        && startOfBlock == other.startOfBlock;
  }

  @Override
  public int hashCode() {
    return Objects.hash(tree, startOfBlock, getExpression());
  }

  @Override
  @SideEffectFree
  public Collection<Node> getOperands() {
    return Collections.emptyList();
  }
}
