/*
 * SonarQube Java
 * Copyright (C) 2012-2016 SonarSource SA
 * mailto:contact AT sonarsource DOT com
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
package org.sonar.java.checks.helpers;

import org.sonar.plugins.java.api.tree.ClassTree;
import org.sonar.plugins.java.api.tree.ExpressionTree;
import org.sonar.plugins.java.api.tree.IdentifierTree;
import org.sonar.plugins.java.api.tree.MemberSelectExpressionTree;
import org.sonar.plugins.java.api.tree.NewClassTree;
import org.sonar.plugins.java.api.tree.Tree;

import javax.annotation.Nullable;
import java.util.Deque;
import java.util.LinkedList;

public class ExpressionsHelper {

  private ExpressionsHelper() {
  }

  public static String concatenate(@Nullable ExpressionTree tree) {
    if(tree == null) {
      return "";
    }
    Deque<String> pieces = new LinkedList<>();
    ExpressionTree expr = tree;
    while (expr.is(Tree.Kind.MEMBER_SELECT)) {
      MemberSelectExpressionTree mse = (MemberSelectExpressionTree) expr;
      pieces.push(mse.identifier().name());
      pieces.push(".");
      expr = mse.expression();
    }
    if (expr.is(Tree.Kind.IDENTIFIER)) {
      IdentifierTree idt = (IdentifierTree) expr;
      pieces.push(idt.name());
    }

    StringBuilder sb = new StringBuilder();
    for (String piece: pieces) {
      sb.append(piece);
    }
    return sb.toString();
  }

  /**
   * Return the correct tree to report on for class trees.
   * @param classTree class tree raising an issue.
   * @return simple name of class tree or identifier in parent expression for anonymous class.
   */
  public static Tree reportOnClassTree(ClassTree classTree) {
    Tree reportTree = classTree.simpleName();
    if(reportTree == null) {
      reportTree = ((NewClassTree) classTree.parent()).identifier();
    }
    return reportTree;
  }


}