/*

  * Licensed to the Apache Software Foundation (ASF) under one or more

  * contributor license agreements.  See the NOTICE file distributed with

  * this work for additional information regarding copyright ownership.

  * The ASF licenses this file to You 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 org.apache.any23.validator.rule;

 import org.apache.any23.validator.DOMDocument;

 import org.apache.any23.validator.Rule;

 import org.apache.any23.validator.RuleContext;

 import org.apache.any23.validator.ValidationReport;

 import org.apache.any23.validator.ValidationReportBuilder;

 import org.w3c.dom.Node;

 import java.util.List;

 /**

  * This rule detects the issue of missing Open Graph namespace.

  *

  * @see OpenGraphNamespaceFix

  * @author Michele Mostarda (mostarda@fbk.eu)

  * @author Davide Palmisano (palmisano@fbk.eu)

  */

 public class MissingOpenGraphNamespaceRule implements Rule {

     public String getHRName() {

         return "missing-opengraph-namespace-rule";

     }

     public boolean applyOn(

             DOMDocument document,

             RuleContext context,

             ValidationReportBuilder validationReportBuilder

     ) {

         List<Node> metas = document.getNodes("/HTML/HEAD/META");

         boolean foundPrecondition = false;

         for(Node meta : metas) {

             Node propertyNode = meta.getAttributes().getNamedItem("property");

             if( propertyNode != null && propertyNode.getTextContent().indexOf("og:") == 0) {

                 foundPrecondition = true;

                 break;

             }

         }

         if(foundPrecondition) {

             Node htmlNode = document.getNode("/HTML");

             if( htmlNode.getAttributes().getNamedItem("xmlns:og") == null) {

                 validationReportBuilder.reportIssue(

                         ValidationReport.IssueLevel.error,

                         "Missing OpenGraph namespace declaration.",

                         htmlNode

                 );

                 return true;

             }

         }

         return false;

     }

 }