/*
 * 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 org.apache.jasper.compiler;


import java.util.HashMap;

import org.apache.jasper.JasperException;

/**
 * Repository of {page, request, session, application}-scoped beans
 */
public class BeanRepository {

    private final HashMap<String,String> beanTypes;
    private final ClassLoader loader;
    private final ErrorDispatcher errDispatcher;

    /**
     * Constructor.
     *
     * @param loader The class loader
     * @param err    The error dispatcher that will be used to report errors
     */
    public BeanRepository(ClassLoader loader, ErrorDispatcher err) {
        this.loader = loader;
        this.errDispatcher = err;
        beanTypes = new HashMap<>();
    }

    /**
     * Registers a scoped bean.
     *
     * @param n the UseBean node
     * @param s the bean name
     * @param type the bean type
     * @param scope the bean scope
     * @throws JasperException if the scope is invalid
     */
    public void addBean(Node.UseBean n, String s, String type, String scope) throws JasperException {

        if (!(scope == null || scope.equals("page") || scope.equals("request") || scope.equals("session") ||
                scope.equals("application"))) {
            errDispatcher.jspError(n, "jsp.error.usebean.badScope");
        }

        beanTypes.put(s, type);
    }

    /**
     * Returns the class of a registered bean.
     *
     * @param bean the bean name
     * @return the bean class
     * @throws JasperException if the class cannot be loaded
     */
    public Class<?> getBeanType(String bean) throws JasperException {
        Class<?> clazz;
        try {
            clazz = loader.loadClass(beanTypes.get(bean));
        } catch (ClassNotFoundException ex) {
            throw new JasperException(ex);
        }
        return clazz;
    }

    /**
     * Checks if a bean with the given name is registered.
     *
     * @param bean the bean name
     * @return true if the bean is registered
     */
    public boolean checkVariable(String bean) {
        return beanTypes.containsKey(bean);
    }

}