/**
 *
 * Copyright the original author or authors
 *
 * 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.jivesoftware.smackx.privacy.provider;

import java.io.IOException;
import java.util.ArrayList;

import org.jivesoftware.smack.datatypes.UInt32;
import org.jivesoftware.smack.packet.IqData;
import org.jivesoftware.smack.packet.XmlEnvironment;
import org.jivesoftware.smack.provider.IqProvider;
import org.jivesoftware.smack.util.ParserUtils;
import org.jivesoftware.smack.xml.XmlPullParser;
import org.jivesoftware.smack.xml.XmlPullParserException;

import org.jivesoftware.smackx.privacy.packet.Privacy;
import org.jivesoftware.smackx.privacy.packet.PrivacyItem;

/**
 * The PrivacyProvider parses {@link Privacy} packets. {@link Privacy}
 * Parses the <code>query</code> sub-document and creates an instance of {@link Privacy}.
 * For each <code>item</code> in the <code>list</code> element, it creates an instance
 * of {@link PrivacyItem}.
 *
 * @author Francisco Vives
 */
public class PrivacyProvider extends IqProvider<Privacy> {

    @Override
    public Privacy parse(XmlPullParser parser, int initialDepth, IqData iqData, XmlEnvironment xmlEnvironment)
                    throws XmlPullParserException, IOException {
        Privacy privacy = new Privacy();
        boolean done = false;
        while (!done) {
            XmlPullParser.Event eventType = parser.next();
            if (eventType == XmlPullParser.Event.START_ELEMENT) {
                // CHECKSTYLE:OFF
                if (parser.getName().equals("active")) {
                    String activeName = parser.getAttributeValue("", "name");
                    if (activeName == null) {
                        privacy.setDeclineActiveList(true);
                    } else {
                        privacy.setActiveName(activeName);
                    }
                }
                else if (parser.getName().equals("default")) {
                    String defaultName = parser.getAttributeValue("", "name");
                    if (defaultName == null) {
                        privacy.setDeclineDefaultList(true);
                    } else {
                        privacy.setDefaultName(defaultName);
                    }
                }
                // CHECKSTYLE:ON
                else if (parser.getName().equals("list")) {
                    parseList(parser, privacy);
                }
            }
            else if (eventType == XmlPullParser.Event.END_ELEMENT) {
                if (parser.getName().equals("query")) {
                    done = true;
                }
            }
        }

        return privacy;
    }

    // Parse the list complex type
    private static void parseList(XmlPullParser parser, Privacy privacy) throws XmlPullParserException, IOException {
        boolean done = false;
        String listName = parser.getAttributeValue("", "name");
        ArrayList<PrivacyItem> items = new ArrayList<>();
        while (!done) {
            XmlPullParser.Event eventType = parser.next();
            if (eventType == XmlPullParser.Event.START_ELEMENT) {
                if (parser.getName().equals("item")) {
                    // CHECKSTYLE:OFF
                    items.add(parseItem(parser));
                    // CHECKSTYLE:ON
                }
            }
            else if (eventType == XmlPullParser.Event.END_ELEMENT) {
                if (parser.getName().equals("list")) {
                    done = true;
                }
            }
        }

        privacy.setPrivacyList(listName, items);
    // CHECKSTYLE:OFF
    }

    // Parse the list complex type
    private static PrivacyItem parseItem(XmlPullParser parser) throws XmlPullParserException, IOException {
    // CHECKSTYLE:ON
        // Retrieves the required attributes
        String actionValue = parser.getAttributeValue("", "action");
        // Set the order number, this attribute is required
        UInt32 order = ParserUtils.getUInt32Attribute(parser, "order");

        // If type is not set, then it's the fall-through case
        String type = parser.getAttributeValue("", "type");

        /*
         * According the action value it sets the allow status. The fall-through action is assumed
         * to be "allow"
         */
        boolean allow;
        switch (actionValue) {
        case "allow":
            allow = true;
            break;
        case "deny":
            allow = false;
            break;
        default:
            // TODO: Should be SmackParsingException.
            throw new IOException("Unknown action value '" + actionValue + "'");
        }

        PrivacyItem item;
        if (type != null) {
            // If the type is not null, then we are dealing with a standard privacy item
            String value = parser.getAttributeValue("", "value");
            item = new PrivacyItem(PrivacyItem.Type.valueOf(type), value, allow, order);
        }
        else {
            // If the type is null, then we are dealing with the fall-through privacy item.
            item = new PrivacyItem(allow, order);
        }
        parseItemChildElements(parser, item);
        return item;
    // CHECKSTYLE:OFF
    }
    // CHECKSTYLE:ON

    private static void parseItemChildElements(XmlPullParser parser, PrivacyItem privacyItem) throws XmlPullParserException, IOException {
        final int initialDepth = parser.getDepth();

        outerloop: while (true) {
            XmlPullParser.Event eventType = parser.next();
            switch (eventType) {
            case START_ELEMENT:
                String name = parser.getName();
                switch (name) {
                case "iq":
                    privacyItem.setFilterIQ(true);
                    break;
                case "message":
                    privacyItem.setFilterMessage(true);
                    break;
                case "presence-in":
                    privacyItem.setFilterPresenceIn(true);
                    break;
                case "presence-out":
                    privacyItem.setFilterPresenceOut(true);
                    break;
                }
                break;
            case END_ELEMENT:
                if (parser.getDepth() == initialDepth) {
                    break outerloop;
                }
                break;
            default:
                // Catch all for incomplete switch (MissingCasesInEnumSwitch) statement.
                break;
            }
        }
    }
}