/*
 * Copyright 2007 Yusuke Yamamoto
 *
 * 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 twitter4j.json;

import org.json.JSONException;
import org.json.JSONObject;

import twitter4j.internal.logging.Logger;

/**
 * @author Dan Checkoway - dcheckoway at gmail.com
 * @since Twitter4J 2.1.9
 */
public final class JSONObjectType {
	private static final Logger logger = Logger.getLogger(JSONObjectType.class);

	/**
	 * Determine the respective object type for a given JSONObject. This method
	 * inspects the object to figure out what type of object it represents. This
	 * is useful when processing JSON events of mixed type from a stream, in
	 * which case you may need to know what type of object to construct, or how
	 * to handle the event properly.
	 * 
	 * @param json the JSONObject whose type should be determined
	 * @return the determined JSONObjectType, or null if not recognized
	 */
	public static Type determine(final JSONObject json) {
		// This code originally lived in AbstractStreamImplementation.
		// I've moved it in here to expose it as a public encapsulation of
		// the object type determination logic.
		if (!json.isNull("sender"))
			return Type.SENDER;
		else if (!json.isNull("text"))
			return Type.STATUS;
		else if (!json.isNull("direct_message"))
			return Type.DIRECT_MESSAGE;
		else if (!json.isNull("delete"))
			return Type.DELETE;
		else if (!json.isNull("limit"))
			return Type.LIMIT;
		else if (!json.isNull("warning"))
			return Type.STALL_WARNING;
		else if (!json.isNull("scrub_geo"))
			return Type.SCRUB_GEO;
		else if (!json.isNull("friends"))
			return Type.FRIENDS;
		else if (!json.isNull("event")) {
			String event;
			try {
				event = json.getString("event");
				if ("favorite".equals(event))
					return Type.FAVORITE;
				else if ("unfavorite".equals(event))
					return Type.UNFAVORITE;
				else if ("follow".equals(event))
					return Type.FOLLOW;
				else if ("unfollow".equals(event))
					return Type.UNFOLLOW;
				else if (event.startsWith("list")) {
					if ("list_member_added".equals(event))
						return Type.USER_LIST_MEMBER_ADDED;
					else if ("list_member_removed".equals(event))
						return Type.USER_LIST_MEMBER_DELETED;
					else if ("list_user_subscribed".equals(event))
						return Type.USER_LIST_SUBSCRIBED;
					else if ("list_user_unsubscribed".equals(event))
						return Type.USER_LIST_UNSUBSCRIBED;
					else if ("list_created".equals(event))
						return Type.USER_LIST_CREATED;
					else if ("list_updated".equals(event))
						return Type.USER_LIST_UPDATED;
					else if ("list_destroyed".equals(event)) return Type.USER_LIST_DESTROYED;
				} else if ("user_update".equals(event))
					return Type.USER_UPDATE;
				else if ("block".equals(event))
					return Type.BLOCK;
				else if ("unblock".equals(event)) return Type.UNBLOCK;
			} catch (final JSONException jsone) {
				try {
					logger.warn("Failed to get event element: ", json.toString(2));
				} catch (final JSONException ignore) {
				}
			}
		} else if (!json.isNull("disconnect")) return Type.DISCONNECTION;
		return Type.UNKNOWN;
	}

	public enum Type {
		SENDER, STATUS, DIRECT_MESSAGE, DELETE, LIMIT, STALL_WARNING, SCRUB_GEO, FRIENDS, FAVORITE, UNFAVORITE, FOLLOW, UNFOLLOW, USER_LIST_MEMBER_ADDED, USER_LIST_MEMBER_DELETED, USER_LIST_SUBSCRIBED, USER_LIST_UNSUBSCRIBED, USER_LIST_CREATED, USER_LIST_UPDATED, USER_LIST_DESTROYED, USER_UPDATE, BLOCK, UNBLOCK, DISCONNECTION, UNKNOWN
	}
}