/*
 * Copyright (c) 2015, 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.
 */
/*
 * $Id: UnsupportedElement.java,v 1.2.4.1 2005/09/05 09:26:51 pvedula Exp $
 */

package com.sun.org.apache.xalan.internal.xsltc.compiler;

import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
import com.sun.org.apache.bcel.internal.generic.INVOKESTATIC;
import com.sun.org.apache.bcel.internal.generic.InstructionList;
import com.sun.org.apache.bcel.internal.generic.PUSH;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ErrorMsg;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Util;
import java.util.ArrayList;
import java.util.List;

Author:
Morten Jorgensen
@LastModified
: Oct 2017/**
 * @author Morten Jorgensen
 * @LastModified: Oct 2017
 */
final class UnsupportedElement extends SyntaxTreeNode {

    private List<SyntaxTreeNode> _fallbacks = null;
    private ErrorMsg _message = null;
    private boolean _isExtension = false;

    
Basic consutrcor - stores element uri/prefix/localname
/**
     * Basic consutrcor - stores element uri/prefix/localname
     */
    public UnsupportedElement(String uri, String prefix, String local, boolean isExtension) {
        super(uri, prefix, local);
        _isExtension = isExtension;
    }

    
There are different categories of unsupported elements (believe it
or not): there are elements within the XSLT namespace (these would
be elements that are not yet implemented), there are extensions of
other XSLT processors and there are unrecognised extension elements
of this XSLT processor. The error message passed to this method
should describe the unsupported element itself and what category
the element belongs in.
/**
     * There are different categories of unsupported elements (believe it
     * or not): there are elements within the XSLT namespace (these would
     * be elements that are not yet implemented), there are extensions of
     * other XSLT processors and there are unrecognised extension elements
     * of this XSLT processor. The error message passed to this method
     * should describe the unsupported element itself and what category
     * the element belongs in.
     */
    public void setErrorMessage(ErrorMsg message) {
        _message = message;
    }

    
Displays the contents of this element
/**
     * Displays the contents of this element
     */
    public void display(int indent) {
        indent(indent);
        Util.println("Unsupported element = " + _qname.getNamespace() +
                     ":" + _qname.getLocalPart());
        displayContents(indent + IndentIncrement);
    }


    
Scan and process all fallback children of the unsupported element.
/**
     * Scan and process all fallback children of the unsupported element.
     */
    private void processFallbacks(Parser parser) {

        List<SyntaxTreeNode> children = getContents();
        if (children != null) {
            final int count = children.size();
            for (int i = 0; i < count; i++) {
                SyntaxTreeNode child = children.get(i);
                if (child instanceof Fallback) {
                    Fallback fallback = (Fallback)child;
                    fallback.activate();
                    fallback.parseContents(parser);
                    if (_fallbacks == null) {
                        _fallbacks = new ArrayList<>();
                    }
                    _fallbacks.add(child);
                }
            }
        }
    }

    
Find any fallback in the descendant nodes; then activate & parse it
/**
     * Find any fallback in the descendant nodes; then activate & parse it
     */
    public void parseContents(Parser parser) {
        processFallbacks(parser);
    }

    
Run type check on the fallback element (if any).
/**
     * Run type check on the fallback element (if any).
     */
    public Type typeCheck(SymbolTable stable) throws TypeCheckError {
        if (_fallbacks != null) {
            int count = _fallbacks.size();
            for (int i = 0; i < count; i++) {
                Fallback fallback = (Fallback)_fallbacks.get(i);
                fallback.typeCheck(stable);
            }
        }
        return Type.Void;
    }

    
Translate the fallback element (if any).
/**
     * Translate the fallback element (if any).
     */
    public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
        if (_fallbacks != null) {
            int count = _fallbacks.size();
            for (int i = 0; i < count; i++) {
                Fallback fallback = (Fallback)_fallbacks.get(i);
                fallback.translate(classGen, methodGen);
            }
        }
        // We only go into the else block in forward-compatibility mode, when
        // the unsupported element has no fallback.
        else {
            // If the unsupported element does not have any fallback child, then
            // at runtime, a runtime error should be raised when the unsupported
            // element is instantiated. Otherwise, no error is thrown.
            ConstantPoolGen cpg = classGen.getConstantPool();
            InstructionList il = methodGen.getInstructionList();

            final int unsupportedElem = cpg.addMethodref(BASIS_LIBRARY_CLASS, "unsupported_ElementF",
                                                         "(" + STRING_SIG + "Z)V");
            il.append(new PUSH(cpg, getQName().toString()));
            il.append(new PUSH(cpg, _isExtension));
            il.append(new INVOKESTATIC(unsupportedElem));
        }
    }
}