/*
    * 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
    *
    *      https://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.commons.xml.secure;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertNotNull;
  import static org.junit.jupiter.api.Assertions.assertNull;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  import java.io.StringReader;
  import java.util.Collections;
  import java.util.Iterator;
  
  import javax.xml.XMLConstants;
  import javax.xml.namespace.NamespaceContext;
  import javax.xml.namespace.QName;
  import javax.xml.xpath.XPath;
  import javax.xml.xpath.XPathConstants;
  import javax.xml.xpath.XPathExpression;
  import javax.xml.xpath.XPathExpressionException;
  import javax.xml.xpath.XPathFactory;
  import javax.xml.xpath.XPathFunctionResolver;
  import javax.xml.xpath.XPathVariableResolver;
  
  import org.junit.jupiter.api.Tag;
  import org.junit.jupiter.api.Test;
  import org.xml.sax.InputSource;
  
  @Tag("xpath")
  class SecureXPathTest {
  
      @Test
      void delegatesEveryXPathMethod() throws Exception {
          final SecureXPath xpath = new SecureXPath(XPathFactory.newInstance().newXPath(), false);
          final NamespaceContext context = new NamespaceContext() {
  
              @Override
              public String getNamespaceURI(final String prefix) {
                  return XMLConstants.NULL_NS_URI;
              }
  
              @Override
              public String getPrefix(final String namespaceUri) {
                  return null;
              }
  
              @Override
              public Iterator<String> getPrefixes(final String namespaceUri) {
                  return Collections.emptyIterator();
              }
          };
          xpath.setNamespaceContext(context);
          xpath.setXPathFunctionResolver((name, arity) -> null);
          xpath.setXPathVariableResolver(name -> null);
          assertNotNull(xpath.getNamespaceContext());
          assertNotNull(xpath.getXPathFunctionResolver());
          assertNotNull(xpath.getXPathVariableResolver());
          assertNotNull(xpath.compile("/root"));
          assertEquals("value", xpath.evaluate("/root/text()", new InputSource(new StringReader("<root>value</root>"))));
          assertEquals("value", xpath.evaluate("/root/text()", new InputSource(new StringReader("<root>value</root>")), XPathConstants.STRING));
          assertEquals("value", xpath.evaluate("/root/text()", SecureXPath.parse(new InputSource(new StringReader("<root>value</root>")), false)));
          assertEquals("value", xpath.evaluate("/root/text()", SecureXPath.parse(new InputSource(new StringReader("<root>value</root>")), false),
                  XPathConstants.STRING));
          xpath.reset();
      }
  
      @Test
      void preservesANullCompiledExpressionFromTheDelegate() throws Exception {
          final XPath delegate = new XPath() {
  
              @Override
              public XPathExpression compile(final String expression) {
                  return null;
              }
  
              @Override
              public String evaluate(final String expression, final InputSource source) {
                  return null;
              }
  
              @Override
              public Object evaluate(final String expression, final InputSource source, final QName returnType) {
                  return null;
              }
 
             @Override
             public String evaluate(final String expression, final Object item) {
                 return null;
             }
 
             @Override
             public Object evaluate(final String expression, final Object item, final QName returnType) {
                 return null;
             }
 
             @Override
             public NamespaceContext getNamespaceContext() {
                 return null;
             }
 
             @Override
             public XPathFunctionResolver getXPathFunctionResolver() {
                 return null;
             }
 
             @Override
             public XPathVariableResolver getXPathVariableResolver() {
                 return null;
             }
 
             @Override
             public void reset() {
             }
 
             @Override
             public void setNamespaceContext(final NamespaceContext context) {
             }
 
             @Override
             public void setXPathFunctionResolver(final XPathFunctionResolver resolver) {
             }
 
             @Override
             public void setXPathVariableResolver(final XPathVariableResolver resolver) {
             }
         };
         assertNull(new SecureXPath(delegate, false).compile("/root"));
     }
 
     @Test
     void wrapsParseFailuresAsXPathExpressionExceptions() {
         final XPathExpressionException exception = assertThrows(XPathExpressionException.class,
                 () -> SecureXPath.parse(new InputSource(new StringReader("<root>")), false));
         assertNotNull(exception.getCause());
     }
 }