/*
 * 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.
 */
/*
 * $Id$
 */

package org.apache.xalan.xsltc.compiler;

import java.util.Vector;

import org.apache.bcel.generic.InstructionList;
import org.apache.xalan.xsltc.compiler.util.ClassGenerator;
import org.apache.xalan.xsltc.compiler.util.ErrorMsg;
import org.apache.xalan.xsltc.compiler.util.MethodGenerator;
import org.apache.xalan.xsltc.compiler.util.Type;
import org.apache.xalan.xsltc.compiler.util.TypeCheckError;
import org.apache.xalan.xsltc.compiler.util.Util;

class TopLevelElement extends SyntaxTreeNode {

    /*
     * List of dependencies with other variables, parameters or
     * keys defined at the top level.
     */
    protected Vector _dependencies = null;

    /**
     * Type check all the children of this node.
     */
    public Type typeCheck(SymbolTable stable) throws TypeCheckError {
	return typeCheckContents(stable);
    }

    /**
     * Translate this node into JVM bytecodes.
     */
    public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
	ErrorMsg msg = new ErrorMsg(ErrorMsg.NOT_IMPLEMENTED_ERR,
				    getClass(), this);
	getParser().reportError(FATAL, msg);
    }
	
    /**
     * Translate this node into a fresh instruction list.
     * The original instruction list is saved and restored.
     */
    public InstructionList compile(ClassGenerator classGen,
				   MethodGenerator methodGen) {
	final InstructionList result, save = methodGen.getInstructionList();
	methodGen.setInstructionList(result = new InstructionList());
	translate(classGen, methodGen);
	methodGen.setInstructionList(save);
	return result;
    }

    public void display(int indent) {
	indent(indent);
	Util.println("TopLevelElement");
	displayContents(indent + IndentIncrement);
    }
    
    /**
     * Add a dependency with other top-level elements like
     * variables, parameters or keys.
     */
    public void addDependency(TopLevelElement other) {
	if (_dependencies == null) {
	    _dependencies = new Vector();
	}
	if (!_dependencies.contains(other)) {
	    _dependencies.addElement(other);
	}
    }

    /**
     * Get the list of dependencies with other top-level elements
     * like variables, parameteres or keys.
     */
    public Vector getDependencies() {
	return _dependencies;
    }

}