/*

 * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.

 */

/*

 * 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 com.sun.org.apache.xpath.internal.functions;

import com.sun.org.apache.xpath.internal.XPathContext;

import com.sun.org.apache.xpath.internal.objects.XObject;

import com.sun.org.apache.xpath.internal.objects.XString;

import com.sun.org.apache.xpath.internal.res.XPATHErrorResources;

import java.io.BufferedInputStream;

import java.io.InputStream;

import java.util.Properties;

import jdk.xml.internal.SecuritySupport;

/**

 * Execute the SystemProperty() function.

 * @xsl.usage advanced

 * @LastModified: Sep 2017

 */

public class FuncSystemProperty extends FunctionOneArg

{

    static final long serialVersionUID = 3694874980992204867L;

  /**

   * The path/filename of the property file: XSLTInfo.properties

   * Maintenance note: see also

   * com.sun.org.apache.xalan.internal.processor.TransformerFactoryImpl.XSLT_PROPERTIES

   */

  static final String XSLT_PROPERTIES =

            "com/sun/org/apache/xalan/internal/res/XSLTInfo.properties";

  /**

   * Execute the function.  The function must return

   * a valid object.

   * @param xctxt The current execution context.

   * @return A valid XObject.

   *

   * @throws javax.xml.transform.TransformerException

   */

  public XObject execute(XPathContext xctxt) throws javax.xml.transform.TransformerException

  {

    String fullName = m_arg0.execute(xctxt).str();

    int indexOfNSSep = fullName.indexOf(':');

    String result;

    String propName = "";

    // List of properties where the name of the

    // property argument is to be looked for.

    Properties xsltInfo = new Properties();

    loadPropertyFile(xsltInfo);

    if (indexOfNSSep > 0)

    {

      String prefix = (indexOfNSSep >= 0)

                      ? fullName.substring(0, indexOfNSSep) : "";

      String namespace;

      namespace = xctxt.getNamespaceContext().getNamespaceForPrefix(prefix);

      propName = (indexOfNSSep < 0)

                 ? fullName : fullName.substring(indexOfNSSep + 1);

      if (namespace.startsWith("http://www.w3.org/XSL/Transform")

              || namespace.equals("http://www.w3.org/1999/XSL/Transform"))

      {

        result = xsltInfo.getProperty(propName);

        if (null == result)

        {

          warn(xctxt, XPATHErrorResources.WG_PROPERTY_NOT_SUPPORTED,

               new Object[]{ fullName });  //"XSL Property not supported: "+fullName);

          return XString.EMPTYSTRING;

        }

      }

      else

      {

        warn(xctxt, XPATHErrorResources.WG_DONT_DO_ANYTHING_WITH_NS,

             new Object[]{ namespace,

                           fullName });  //"Don't currently do anything with namespace "+namespace+" in property: "+fullName);

        try

        {

          result = SecuritySupport.getSystemProperty(propName);

          if (null == result)

          {

            // result = System.getenv(propName);

            return XString.EMPTYSTRING;

          }

        }

        catch (SecurityException se)

        {

          warn(xctxt, XPATHErrorResources.WG_SECURITY_EXCEPTION,

               new Object[]{ fullName });  //"SecurityException when trying to access XSL system property: "+fullName);

          return XString.EMPTYSTRING;

        }

      }

    }

    else

    {

      try

      {

        result = SecuritySupport.getSystemProperty(fullName);

        if (null == result)

        {

          // result = System.getenv(fullName);

          return XString.EMPTYSTRING;

        }

      }

      catch (SecurityException se)

      {

        warn(xctxt, XPATHErrorResources.WG_SECURITY_EXCEPTION,

             new Object[]{ fullName });  //"SecurityException when trying to access XSL system property: "+fullName);

        return XString.EMPTYSTRING;

      }

    }

    if (propName.equals("version") && result.length() > 0)

    {

      try

      {

        // Needs to return the version number of the spec we conform to.

        return new XString("1.0");

      }

      catch (Exception ex)

      {

        return new XString(result);

      }

    }

    else

      return new XString(result);

  }

  /**

   * Retrieve a property bundle from XSLT_PROPERTIES

   *

   * @param target The target property bag the file will be placed into.

   */

  private void loadPropertyFile(Properties target)

  {

    try

    {

      // Use SecuritySupport class to provide privileged access to property file

      InputStream is = SecuritySupport.getResourceAsStream(XSLT_PROPERTIES);

      // get a buffered version

      try (BufferedInputStream bis = new BufferedInputStream(is)) {

          target.load(bis);  // and load up the property bag from this

      }

    }

    catch (Exception ex)

    {

      // ex.printStackTrace();

      throw new com.sun.org.apache.xml.internal.utils.WrappedRuntimeException(ex);

    }

  }

}