/*
 * Copyright (c) 2006-2017 DMDirc Developers
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
 * documentation files (the "Software"), to deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
 * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS
 * OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

package com.dmdirc.addons.jpq;

import com.dmdirc.config.prefs.PreferencesSetting;
import com.dmdirc.config.prefs.PreferencesType;
import com.dmdirc.events.ChannelSelfJoinEvent;
import com.dmdirc.events.ChannelSelfPartEvent;
import com.dmdirc.events.GroupChatPrefsRequestedEvent;
import com.dmdirc.events.ServerConnectedEvent;
import com.dmdirc.events.ServerDisconnectedEvent;
import com.dmdirc.interfaces.Connection;
import com.dmdirc.interfaces.ConnectionManager;
import com.dmdirc.events.eventbus.EventBus;
import com.dmdirc.interfaces.GroupChat;
import com.dmdirc.plugins.PluginDomain;

import com.google.common.annotations.VisibleForTesting;

import java.util.HashMap;
import java.util.Map;

import javax.inject.Inject;

import net.engio.mbassy.listener.Handler;

/**
 * Provides the ability to hide joins, parts and quits from a {@link GroupChat}.
 */
public class JPQManager {

    private final String domain;
    private final ConnectionManager connectionManager;
    private final GroupChatHandlerFactory groupChatHandlerFactory;
    private final EventBus eventBus;
    private final Map<GroupChat, GroupChatHandler> groupChatHandlers;

    @Inject
    public JPQManager(
            @PluginDomain(JPQPlugin.class) final String domain,
            final ConnectionManager connectionManager,
            final GroupChatHandlerFactory groupChatHandlerFactory,
            final EventBus eventBus) {
        this.domain = domain;
        this.connectionManager = connectionManager;
        this.groupChatHandlerFactory = groupChatHandlerFactory;
        this.eventBus = eventBus;
        groupChatHandlers = new HashMap<>();
    }

    /**
     * Unloads this manager, removing required listeners and bindings.
     */
    public void load() {
        connectionManager.getConnections().forEach(this::addGroupChatHandler);
        eventBus.subscribe(this);
    }

    /**
     * Loads this manager, adding required listeners and bindings.
     */
    public void unload() {
        connectionManager.getConnections().forEach(this::removeGroupChatHandler);
        eventBus.unsubscribe(this);
    }

    @VisibleForTesting
    @Handler
    void handleConnectionAdded(final ServerConnectedEvent event) {
        addGroupChatHandler(event.getConnection());
    }

    @VisibleForTesting
    @Handler
    void handleConnectionRemoved(final ServerDisconnectedEvent event) {
        removeGroupChatHandler(event.getConnection());
    }
    
    @VisibleForTesting
    @Handler
    void handleGroupChatAdded(final ChannelSelfJoinEvent event) {
        addGroupChatHandler(event.getChannel());
    }
    
    @VisibleForTesting
    @Handler
    void handleGroupChatRemoved(final ChannelSelfPartEvent event) {
        removeGroupChatHandler(event.getChannel());
    }

    @VisibleForTesting
    @Handler
    void handleGroupChatPrefs(final GroupChatPrefsRequestedEvent event) {
        event.getCategory().addSetting(new PreferencesSetting(PreferencesType.BOOLEAN,
                domain, "hidejpq", "Hide J/P/Q", "Hides joins, parts and quits in a group chat.",
                event.getConfig(), event.getIdentity()));
    }

    private void addGroupChatHandler(final Connection connection) {
        connection.getGroupChatManager().getChannels().forEach(this::addGroupChatHandler);
    }

    private void addGroupChatHandler(final GroupChat groupChat) {
        groupChatHandlers.computeIfAbsent(groupChat, groupChatHandlerFactory::get);
    }

    private void removeGroupChatHandler(final Connection connection) {
        connection.getGroupChatManager().getChannels().forEach(this::removeGroupChatHandler);
    }

    private void removeGroupChatHandler(final GroupChat groupChat) {
        final GroupChatHandler groupChatHandler = groupChatHandlers.remove(groupChat);
        if (groupChatHandler != null) {
            groupChatHandler.unload();
        }
    }
}