/*

 * Copyright (c) 2013, 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.jaxp;

import com.sun.org.apache.xalan.internal.res.XSLMessages;

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

import com.sun.org.apache.xpath.internal.functions.FuncExtFunction;

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

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

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

import java.util.ArrayList;

import java.util.List;

import javax.xml.namespace.QName;

import javax.xml.xpath.XPathFunction;

import javax.xml.xpath.XPathFunctionException;

import javax.xml.xpath.XPathFunctionResolver;

import jdk.xml.internal.JdkXmlFeatures;

/**

 *

 * @author Ramesh Mandava

 * @LastModified: Nov 2017

 */

public class JAXPExtensionsProvider implements ExtensionsProvider {

    private final XPathFunctionResolver resolver;

    private boolean extensionInvocationDisabled = false;

    public JAXPExtensionsProvider(XPathFunctionResolver resolver) {

        this.resolver = resolver;

        this.extensionInvocationDisabled = false;

    }

    public JAXPExtensionsProvider(XPathFunctionResolver resolver,

        boolean featureSecureProcessing, JdkXmlFeatures featureManager ) {

        this.resolver = resolver;

        if (featureSecureProcessing &&

                !featureManager.getFeature(JdkXmlFeatures.XmlFeature.ENABLE_EXTENSION_FUNCTION)) {

            this.extensionInvocationDisabled = true;

        }

    }

    /**

     * Is the extension function available?

     */

    public boolean functionAvailable(String ns, String funcName)

          throws javax.xml.transform.TransformerException {

      try {

        if ( funcName == null ) {

            String fmsg = XSLMessages.createXPATHMessage(

                XPATHErrorResources.ER_ARG_CANNOT_BE_NULL,

                new Object[] {"Function Name"} );

            throw new NullPointerException ( fmsg );

        }

        //Find the XPathFunction corresponding to namespace and funcName

        javax.xml.namespace.QName myQName = new QName( ns, funcName );

        javax.xml.xpath.XPathFunction xpathFunction =

            resolver.resolveFunction ( myQName, 0 );

        if (  xpathFunction == null ) {

            return false;

        }

        return true;

      } catch ( Exception e ) {

        return false;

      }

    }

    /**

     * Is the extension element available?

     */

    public boolean elementAvailable(String ns, String elemName)

          throws javax.xml.transform.TransformerException {

        return false;

    }

    /**

     * Execute the extension function.

     */

    public Object extFunction(String ns, String funcName, List<XObject> argVec,

        Object methodKey) throws javax.xml.transform.TransformerException {

        try {

            if ( funcName == null ) {

                String fmsg = XSLMessages.createXPATHMessage(

                    XPATHErrorResources.ER_ARG_CANNOT_BE_NULL,

                    new Object[] {"Function Name"} );

                throw new NullPointerException ( fmsg );

            }

            //Find the XPathFunction corresponding to namespace and funcName

            javax.xml.namespace.QName myQName = new QName( ns, funcName );

            // JAXP 1.3 spec says When XMLConstants.FEATURE_SECURE_PROCESSING

            // feature is set then invocation of extension functions need to

            // throw XPathFunctionException

            if ( extensionInvocationDisabled ) {

                String fmsg = XSLMessages.createXPATHMessage(

                    XPATHErrorResources.ER_EXTENSION_FUNCTION_CANNOT_BE_INVOKED,

                    new Object[] { myQName.toString() } );

                throw new XPathFunctionException ( fmsg );

            }

            // Assuming user is passing all the needed parameters ( including

            // default values )

            int arity = argVec.size();

            javax.xml.xpath.XPathFunction xpathFunction =

                resolver.resolveFunction ( myQName, arity );

            // not using methodKey

            List<Object> argList = new ArrayList<>( arity);

            for ( int i=0; i<arity; i++ ) {

                XObject argument = argVec.get( i );

                // XNodeSet object() returns NodeVector and not NodeList

                // Explicitly getting NodeList by using nodelist()

                if ( argument instanceof XNodeSet ) {

                    argList.add ( i, ((XNodeSet)argument).nodelist() );

                } else if ( argument instanceof XObject ) {

                    Object passedArgument = argument.object();

                    argList.add ( i, passedArgument );

                } else {

                    argList.add ( i, argument );

                }

            }

            return ( xpathFunction.evaluate ( argList ));

        } catch ( XPathFunctionException xfe ) {

            // If we get XPathFunctionException then we want to terminate

            // further execution by throwing WrappedRuntimeException

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

        } catch ( Exception e ) {

            throw new javax.xml.transform.TransformerException ( e );

        }

    }

    /**

     * Execute the extension function.

     */

    public Object extFunction(FuncExtFunction extFunction, List<XObject> argVec)

        throws javax.xml.transform.TransformerException {

        try {

            String namespace = extFunction.getNamespace();

            String functionName = extFunction.getFunctionName();

            int arity = extFunction.getArgCount();

            javax.xml.namespace.QName myQName =

                new javax.xml.namespace.QName( namespace, functionName );

            // JAXP 1.3 spec says  When XMLConstants.FEATURE_SECURE_PROCESSING

            // feature is set then invocation of extension functions need to

            // throw XPathFunctionException

            if ( extensionInvocationDisabled ) {

                String fmsg = XSLMessages.createXPATHMessage(

                    XPATHErrorResources.ER_EXTENSION_FUNCTION_CANNOT_BE_INVOKED,

                        new Object[] { myQName.toString() } );

                throw new XPathFunctionException ( fmsg );

            }

            XPathFunction xpathFunction =

                resolver.resolveFunction( myQName, arity );

            List<Object> argList = new ArrayList<>( arity);

            for ( int i=0; i<arity; i++ ) {

                XObject argument = argVec.get( i );

                // XNodeSet object() returns NodeVector and not NodeList

                // Explicitly getting NodeList by using nodelist()

                if ( argument instanceof XNodeSet ) {

                    argList.add ( i, ((XNodeSet)argument).nodelist() );

                } else if ( argument instanceof XObject ) {

                    Object passedArgument = argument.object();

                    argList.add ( i, passedArgument );

                } else {

                    argList.add ( i, argument );

                }

            }

            return ( xpathFunction.evaluate ( argList ));

        } catch ( XPathFunctionException xfe ) {

            // If we get XPathFunctionException then we want to terminate

            // further execution by throwing WrappedRuntimeException

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

        } catch ( Exception e ) {

            throw new javax.xml.transform.TransformerException ( e );

        }

    }

}