/*
 * 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;

import com.google.common.base.Strings;
import com.google.common.collect.ImmutableList;
import org.sonar.check.Rule;
import org.sonar.check.RuleProperty;
import org.sonar.plugins.java.api.IssuableSubscriptionVisitor;
import org.sonar.plugins.java.api.tree.SyntaxTrivia;
import org.sonar.plugins.java.api.tree.Tree;
import org.sonar.squidbridge.annotations.RuleTemplate;

import javax.annotation.Nullable;
import java.util.List;
import java.util.regex.Pattern;

@Rule(key = "S124")
@RuleTemplate
public class CommentRegularExpressionCheck extends IssuableSubscriptionVisitor {

  private static final String DEFAULT_REGULAR_EXPRESSION = "";
  private static final String DEFAULT_MESSAGE = "The regular expression matches this comment.";

  @Nullable
  private Pattern pattern = null;

  @RuleProperty(
    key = "regularExpression",
    description = "The regular expression",
    defaultValue = "" + DEFAULT_REGULAR_EXPRESSION)
  public String regularExpression = DEFAULT_REGULAR_EXPRESSION;

  @RuleProperty(
    key = "message",
    description = "The issue message",
    defaultValue = "" + DEFAULT_MESSAGE)
  public String message = DEFAULT_MESSAGE;

  @Override
  public List<Tree.Kind> nodesToVisit() {
    return ImmutableList.of(Tree.Kind.TRIVIA);
  }

  @Override
  public void visitTrivia(SyntaxTrivia syntaxTrivia) {
    if (pattern == null && !Strings.isNullOrEmpty(regularExpression)) {
      try {
        pattern = Pattern.compile(regularExpression, Pattern.DOTALL);
      } catch (RuntimeException e) {
        throw new IllegalArgumentException("Unable to compile regular expression: " + regularExpression, e);
      }
    }
    if (pattern != null && pattern.matcher(syntaxTrivia.comment()).matches()) {
      addIssue(syntaxTrivia.startLine(), message);
    }
  }

}