/*
 * 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.modeshape.webdav;

import java.util.Hashtable;
import javax.servlet.http.HttpServletResponse;

/**
 * Wraps the HttpServletResponse class to abstract the specific protocol used. To support other protocols we would only need to
 * modify this class and the WebDavRetCode classes.
 * 
 * @author Marc Eaddy
 * @version 1.0, 16 Nov 1997
 */
public class WebdavStatus {

    // ----------------------------------------------------- Instance Variables

    /**
     * This Hashtable contains the mapping of HTTP and WebDAV status codes to descriptive text. This is a static variable.
     */
    private static Hashtable<Integer, String> mapStatusCodes = new Hashtable<Integer, String>();

    // ------------------------------------------------------ HTTP Status Codes

    /**
     * Status code (200) indicating the request succeeded normally.
     */
    public static final int SC_OK = HttpServletResponse.SC_OK;

    /**
     * Status code (201) indicating the request succeeded and created a new resource on the server.
     */
    public static final int SC_CREATED = HttpServletResponse.SC_CREATED;

    /**
     * Status code (202) indicating that a request was accepted for processing, but was not completed.
     */
    public static final int SC_ACCEPTED = HttpServletResponse.SC_ACCEPTED;

    /**
     * Status code (204) indicating that the request succeeded but that there was no new information to return.
     */
    public static final int SC_NO_CONTENT = HttpServletResponse.SC_NO_CONTENT;

    /**
     * Status code (301) indicating that the resource has permanently moved to a new location, and that future references should
     * use a new URI with their requests.
     */
    public static final int SC_MOVED_PERMANENTLY = HttpServletResponse.SC_MOVED_PERMANENTLY;

    /**
     * Status code (302) indicating that the resource has temporarily moved to another location, but that future references should
     * still use the original URI to access the resource.
     */
    public static final int SC_MOVED_TEMPORARILY = HttpServletResponse.SC_MOVED_TEMPORARILY;

    /**
     * Status code (304) indicating that a conditional GET operation found that the resource was available and not modified.
     */
    public static final int SC_NOT_MODIFIED = HttpServletResponse.SC_NOT_MODIFIED;

    /**
     * Status code (400) indicating the request sent by the client was syntactically incorrect.
     */
    public static final int SC_BAD_REQUEST = HttpServletResponse.SC_BAD_REQUEST;

    /**
     * Status code (401) indicating that the request requires HTTP authentication.
     */
    public static final int SC_UNAUTHORIZED = HttpServletResponse.SC_UNAUTHORIZED;

    /**
     * Status code (403) indicating the server understood the request but refused to fulfill it.
     */
    public static final int SC_FORBIDDEN = HttpServletResponse.SC_FORBIDDEN;

    /**
     * Status code (404) indicating that the requested resource is not available.
     */
    public static final int SC_NOT_FOUND = HttpServletResponse.SC_NOT_FOUND;

    /**
     * Status code (500) indicating an error inside the HTTP service which prevented it from fulfilling the request.
     */
    public static final int SC_INTERNAL_SERVER_ERROR = HttpServletResponse.SC_INTERNAL_SERVER_ERROR;

    /**
     * Status code (501) indicating the HTTP service does not support the functionality needed to fulfill the request.
     */
    public static final int SC_NOT_IMPLEMENTED = HttpServletResponse.SC_NOT_IMPLEMENTED;

    /**
     * Status code (502) indicating that the HTTP server received an invalid response from a server it consulted when acting as a
     * proxy or gateway.
     */
    public static final int SC_BAD_GATEWAY = HttpServletResponse.SC_BAD_GATEWAY;

    /**
     * Status code (503) indicating that the HTTP service is temporarily overloaded, and unable to handle the request.
     */
    public static final int SC_SERVICE_UNAVAILABLE = HttpServletResponse.SC_SERVICE_UNAVAILABLE;

    /**
     * Status code (100) indicating the client may continue with its request. This interim response is used to inform the client
     * that the initial part of the request has been received and has not yet been rejected by the server.
     */
    public static final int SC_CONTINUE = 100;

    /**
     * Status code (405) indicating the method specified is not allowed for the resource.
     */
    public static final int SC_METHOD_NOT_ALLOWED = 405;

    /**
     * Status code (409) indicating that the request could not be completed due to a conflict with the current state of the
     * resource.
     */
    public static final int SC_CONFLICT = 409;

    /**
     * Status code (412) indicating the precondition given in one or more of the request-header fields evaluated to false when it
     * was tested on the server.
     */
    public static final int SC_PRECONDITION_FAILED = 412;

    /**
     * Status code (413) indicating the server is refusing to process a request because the request entity is larger than the
     * server is willing or able to process.
     */
    public static final int SC_REQUEST_TOO_LONG = 413;

    /**
     * Status code (415) indicating the server is refusing to service the request because the entity of the request is in a format
     * not supported by the requested resource for the requested method.
     */
    public static final int SC_UNSUPPORTED_MEDIA_TYPE = 415;

    /**
     * The 424 (Failed Dependency) status code means that the method could not be performed on the resource because the requested
     * action depended on another action and that action failed. For example, if a command in a PROPPATCH method fails then, at
     * minimum the rest of the commands will also fail with 424 (Failed Dependency).
     */
    public static final int SC_FAILED_DEPENDENCY = 424;

    // -------------------------------------------- Extended WebDav status code

    /**
     * Status code (207) indicating that the response requires providing status for multiple independent operations.
     */
    public static final int SC_MULTI_STATUS = 207;

    // This one colides with HTTP 1.1
    // "207 Parital Update OK"

    /**
     * Status code (418) indicating the entity body submitted with the PATCH method was not understood by the resource.
     */
    public static final int SC_UNPROCESSABLE_ENTITY = 418;

    // This one colides with HTTP 1.1
    // "418 Reauthentication Required"

    /**
     * Status code (419) indicating that the resource does not have sufficient space to record the state of the resource after the
     * execution of this method.
     */
    public static final int SC_INSUFFICIENT_SPACE_ON_RESOURCE = 419;

    // This one colides with HTTP 1.1
    // "419 Proxy Reauthentication Required"

    /**
     * Status code (420) indicating the method was not executed on a particular resource within its scope because some part of the
     * method's execution failed causing the entire method to be aborted.
     */
    public static final int SC_METHOD_FAILURE = 420;

    /**
     * Status code (423) indicating the destination resource of a method is locked, and either the request did not contain a valid
     * Lock-Info header, or the Lock-Info header identifies a lock held by another principal.
     */
    public static final int SC_LOCKED = 423;

    // ------------------------------------------------------------ Initializer

    static {
        // HTTP 1.0 Status Code
        addStatusCodeMap(SC_OK, "OK");
        addStatusCodeMap(SC_CREATED, "Created");
        addStatusCodeMap(SC_ACCEPTED, "Accepted");
        addStatusCodeMap(SC_NO_CONTENT, "No Content");
        addStatusCodeMap(SC_MOVED_PERMANENTLY, "Moved Permanently");
        addStatusCodeMap(SC_MOVED_TEMPORARILY, "Moved Temporarily");
        addStatusCodeMap(SC_NOT_MODIFIED, "Not Modified");
        addStatusCodeMap(SC_BAD_REQUEST, "Bad Request");
        addStatusCodeMap(SC_UNAUTHORIZED, "Unauthorized");
        addStatusCodeMap(SC_FORBIDDEN, "Forbidden");
        addStatusCodeMap(SC_NOT_FOUND, "Not Found");
        addStatusCodeMap(SC_INTERNAL_SERVER_ERROR, "Internal Server Error");
        addStatusCodeMap(SC_NOT_IMPLEMENTED, "Not Implemented");
        addStatusCodeMap(SC_BAD_GATEWAY, "Bad Gateway");
        addStatusCodeMap(SC_SERVICE_UNAVAILABLE, "Service Unavailable");
        addStatusCodeMap(SC_CONTINUE, "Continue");
        addStatusCodeMap(SC_METHOD_NOT_ALLOWED, "Method Not Allowed");
        addStatusCodeMap(SC_CONFLICT, "Conflict");
        addStatusCodeMap(SC_PRECONDITION_FAILED, "Precondition Failed");
        addStatusCodeMap(SC_REQUEST_TOO_LONG, "Request Too Long");
        addStatusCodeMap(SC_UNSUPPORTED_MEDIA_TYPE, "Unsupported Media Type");
        // WebDav Status Codes
        addStatusCodeMap(SC_MULTI_STATUS, "Multi-Status");
        addStatusCodeMap(SC_UNPROCESSABLE_ENTITY, "Unprocessable Entity");
        addStatusCodeMap(SC_INSUFFICIENT_SPACE_ON_RESOURCE, "Insufficient Space On Resource");
        addStatusCodeMap(SC_METHOD_FAILURE, "Method Failure");
        addStatusCodeMap(SC_LOCKED, "Locked");
        addStatusCodeMap(SC_FAILED_DEPENDENCY, "Failed Dependency");
    }

    // --------------------------------------------------------- Public Methods

    /**
     * Returns the HTTP status text for the HTTP or WebDav status code specified by looking it up in the static mapping. This is a
     * static function.
     * 
     * @param nHttpStatusCode [IN] HTTP or WebDAV status code
     * @return A string with a short descriptive phrase for the HTTP status code (e.g., "OK").
     */
    public static String getStatusText( int nHttpStatusCode ) {
        if (!mapStatusCodes.containsKey(nHttpStatusCode)) {
            return "";
        }
        return mapStatusCodes.get(nHttpStatusCode);
    }

    // -------------------------------------------------------- Private Methods

    /**
     * Adds a new status code -> status text mapping. This is a static method because the mapping is a static variable.
     * 
     * @param nKey [IN] HTTP or WebDAV status code
     * @param strVal [IN] HTTP status text
     */
    private static void addStatusCodeMap( int nKey,
                                          String strVal ) {
        mapStatusCodes.put(nKey, strVal);
    }
}
