/*
 * Copyright 1999,2004 The Apache Software Foundation.
 *
 * Licensed 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.commons.jelly.tags.fmt;

import org.apache.commons.jelly.JellyContext;


/**
 * Class supporting access to configuration data.
 * @author <a href="mailto:willievu@yahoo.com">Willie Vu</a>
 * @version 1.1
 */
public class Config {

    /*
     * I18N/Formatting actions related configuration data
     */

    /**
     * Name of configuration setting for application- (as opposed to browser-)
     * based preferred locale
     */
    public static final String FMT_LOCALE
    = "org.apache.commons.jelly.tags.fmt.locale";

    /**
     * Name of configuration setting for fallback locale
     */
    public static final String FMT_FALLBACK_LOCALE
    = "org.apache.commons.jelly.tags.fmt.fallbackLocale";

    /**
     * Name of configuration setting for i18n localization context
     */
    public static final String FMT_LOCALIZATION_CONTEXT
    = "org.apache.commons.jelly.tags.fmt.localizationContext";

    /**
     * Name of localization setting for time zone
     */
    public static final String FMT_TIME_ZONE
    = "org.apache.commons.jelly.tags.fmt.timeZone";


    /**
     * Looks up a configuration variable in the given scope.
     *
     * <p> The lookup of configuration variables is performed as if each scope
     * had its own name space, that is, the same configuration variable name
     * in one scope does not replace one stored in a different scope.
     *
     * @param jc Page context in which the configuration variable is to be
     * looked up
     * @param name Configuration variable name
     * @param scope Scope in which the configuration variable is to be looked
     * up
     *
     * @return The <tt>java.lang.Object</tt> associated with the configuration
     * variable, or null if it is not defined.
     */
//    public static Object get(JellyContext jc, String name, int scope) {
//        switch (scope) {
//            case JellyContext.PAGE_SCOPE:
//                return jc.getAttribute(name + PAGE_SCOPE_SUFFIX, scope);
//            case JellyContext.REQUEST_SCOPE:
//                return jc.getAttribute(name + REQUEST_SCOPE_SUFFIX, scope);
//            case JellyContext.SESSION_SCOPE:
//                return jc.getAttribute(name + SESSION_SCOPE_SUFFIX, scope);
//            case JellyContext.APPLICATION_SCOPE:
//                return jc.getAttribute(name + APPLICATION_SCOPE_SUFFIX, scope);
//            default:
//                throw new IllegalArgumentException("unknown scope");
//        }
//    }

    /**
     * Looks up a configuration variable in the "request" scope.
     *
     * <p> The lookup of configuration variables is performed as if each scope
     * had its own name space, that is, the same configuration variable name
     * in one scope does not replace one stored in a different scope.
     *
     * @param request Request object in which the configuration variable is to
     * be looked up
     * @param name Configuration variable name
     *
     * @return The <tt>java.lang.Object</tt> associated with the configuration
     * variable, or null if it is not defined.
     */
//    public static Object get(ServletRequest request, String name) {
//        return request.getAttribute(name + REQUEST_SCOPE_SUFFIX);
//    }

    /**
     * Looks up a configuration variable in the "session" scope.
     *
     * <p> The lookup of configuration variables is performed as if each scope
     * had its own name space, that is, the same configuration variable name
     * in one scope does not replace one stored in a different scope.
     *
     * @param session Session object in which the configuration variable is to
     * be looked up
     * @param name Configuration variable name
     *
     * @return The <tt>java.lang.Object</tt> associated with the configuration
     * variable, or null if it is not defined.
     */
//    public static Object get(HttpSession session, String name) {
//        return session.getAttribute(name + SESSION_SCOPE_SUFFIX);
//    }

    /**
     * Looks up a configuration variable in the "application" scope.
     *
     * <p> The lookup of configuration variables is performed as if each scope
     * had its own name space, that is, the same configuration variable name
     * in one scope does not replace one stored in a different scope.
     *
     * @param context Servlet context in which the configuration variable is
     * to be looked up
     * @param name Configuration variable name
     *
     * @return The <tt>java.lang.Object</tt> associated with the configuration
     * variable, or null if it is not defined.
     */
//    public static Object get(ServletContext context, String name) {
//        return context.getAttribute(name + APPLICATION_SCOPE_SUFFIX);
//    }

    /**
     * Sets the value of a configuration variable in the given scope.
     *
     * <p> Setting the value of a configuration variable is performed as if
     * each scope had its own namespace, that is, the same configuration
     * variable name in one scope does not replace one stored in a different
     * scope.
     *
     * @param jc Page context in which the configuration variable is to be set
     * @param name Configuration variable name
     * @param value Configuration variable value
     * @param scope Scope in which the configuration variable is to be set
     */
//    public static void set(JellyContext jc, String name, Object value,
//    int scope) {
//        switch (scope) {
//            case JellyContext.PAGE_SCOPE:
//                jc.setAttribute(name + PAGE_SCOPE_SUFFIX, value, scope);
//                break;
//            case JellyContext.REQUEST_SCOPE:
//                jc.setAttribute(name + REQUEST_SCOPE_SUFFIX, value, scope);
//                break;
//            case JellyContext.SESSION_SCOPE:
//                jc.setAttribute(name + SESSION_SCOPE_SUFFIX, value, scope);
//                break;
//            case JellyContext.APPLICATION_SCOPE:
//                jc.setAttribute(name + APPLICATION_SCOPE_SUFFIX, value, scope);
//                break;
//            default:
//                throw new IllegalArgumentException("unknown scope");
//        }
//    }

    /**
     * Sets the value of a configuration variable in the "request" scope.
     *
     * <p> Setting the value of a configuration variable is performed as if
     * each scope had its own namespace, that is, the same configuration
     * variable name in one scope does not replace one stored in a different
     * scope.
     *
     * @param request Request object in which the configuration variable is to
     * be set
     * @param name Configuration variable name
     * @param value Configuration variable value
     */
//    public static void set(ServletRequest request, String name, Object value) {
//        request.setAttribute(name + REQUEST_SCOPE_SUFFIX, value);
//    }

    /**
     * Sets the value of a configuration variable in the "session" scope.
     *
     * <p> Setting the value of a configuration variable is performed as if
     * each scope had its own namespace, that is, the same configuration
     * variable name in one scope does not replace one stored in a different
     * scope.
     *
     * @param session Session object in which the configuration variable is to
     * be set
     * @param name Configuration variable name
     * @param value Configuration variable value
     */
//    public static void set(HttpSession session, String name, Object value) {
//        session.setAttribute(name + SESSION_SCOPE_SUFFIX, value);
//    }

    /**
     * Sets the value of a configuration variable in the "application" scope.
     *
     * <p> Setting the value of a configuration variable is performed as if
     * each scope had its own namespace, that is, the same configuration
     * variable name in one scope does not replace one stored in a different
     * scope.
     *
     * @param context Servlet context in which the configuration variable is to
     * be set
     * @param name Configuration variable name
     * @param value Configuration variable value
     */
//    public static void set(ServletContext context, String name, Object value) {
//        context.setAttribute(name + APPLICATION_SCOPE_SUFFIX, value);
//    }

    /**
     * Removes a configuration variable from the given scope.
     *
     * <p> Removing a configuration variable is performed as if each scope had
     * its own namespace, that is, the same configuration variable name in one
     * scope does not impact one stored in a different scope.
     *
     * @param jc Page context from which the configuration variable is to be
     * removed
     * @param name Configuration variable name
     * @param scope Scope from which the configuration variable is to be
     * removed
     */
//    public static void remove(JellyContext jc, String name, int scope) {
//        switch (scope) {
//            case JellyContext.PAGE_SCOPE:
//                jc.removeAttribute(name + PAGE_SCOPE_SUFFIX, scope);
//                break;
//            case JellyContext.REQUEST_SCOPE:
//                jc.removeAttribute(name + REQUEST_SCOPE_SUFFIX, scope);
//                break;
//            case JellyContext.SESSION_SCOPE:
//                jc.removeAttribute(name + SESSION_SCOPE_SUFFIX, scope);
//                break;
//            case JellyContext.APPLICATION_SCOPE:
//                jc.removeAttribute(name + APPLICATION_SCOPE_SUFFIX, scope);
//                break;
//            default:
//                throw new IllegalArgumentException("unknown scope");
//        }
//    }

    /**
     * Removes a configuration variable from the "request" scope.
     *
     * <p> Removing a configuration variable is performed as if each scope had
     * its own namespace, that is, the same configuration variable name in one
     * scope does not impact one stored in a different scope.
     *
     * @param request Request object from which the configuration variable is
     * to be removed
     * @param name Configuration variable name
     */
//    public static void remove(ServletRequest request, String name) {
//        request.removeAttribute(name + REQUEST_SCOPE_SUFFIX);
//    }

    /**
     * Removes a configuration variable from the "session" scope.
     *
     * <p> Removing a configuration variable is performed as if each scope had
     * its own namespace, that is, the same configuration variable name in one
     * scope does not impact one stored in a different scope.
     *
     * @param session Session object from which the configuration variable is
     * to be removed
     * @param name Configuration variable name
     */
//    public static void remove(HttpSession session, String name) {
//        session.removeAttribute(name + SESSION_SCOPE_SUFFIX);
//    }

    /**
     * Removes a configuration variable from the "application" scope.
     *
     * <p> Removing a configuration variable is performed as if each scope had
     * its own namespace, that is, the same configuration variable name in one
     * scope does not impact one stored in a different scope.
     *
     * @param context Servlet context from which the configuration variable is
     * to be removed
     * @param name Configuration variable name
     */
//    public static void remove(ServletContext context, String name) {
//        context.removeAttribute(name + APPLICATION_SCOPE_SUFFIX);
//    }

    /**
     * Finds the value associated with a specific configuration setting
     * identified by its context initialization parameter name.
     *
     * <p> For each of the JSP scopes (page, request, session, application),
     * get the value of the configuration variable identified by <tt>name</tt>
     * using method <tt>get()</tt>. Return as soon as a non-null value is
     * found. If no value is found, get the value of the context initialization
     * parameter identified by <tt>name</tt>.
     *
     * @param jc Page context in which the configuration setting is to be
     * searched
     * @param name Context initialization parameter name of the configuration
     * setting
     *
     * @return The <tt>java.lang.Object</tt> associated with the configuration
     * setting identified by <tt>name</tt>, or null if it is not defined.
     */
//    public static Object find(JellyContext jc, String name) {
//        Object ret = jc.getVariable(name, JellyContext.PAGE_SCOPE);
//        if (ret == null) {
//            ret = get(jc, name, JellyContext.REQUEST_SCOPE);
//            if (ret == null) {
//                if (jc.getSession() != null) {
//                    // check session only if a session is present
//                    ret = get(jc, name, JellyContext.SESSION_SCOPE);
//                }
//                if (ret == null) {
//                    ret = get(jc, name, JellyContext.APPLICATION_SCOPE);
//                    if (ret == null) {
//                        ret = jc.getServletContext().getInitParameter(name);
//                    }
//                }
//            }
//        }
//
//        return ret;
//    }
}