/***
 * Coalevo Project 
 * http://www.coalevo.net
 *
 * (c) Verein zur Foerderung der Internetkommunikation, Austria 
 * http://www.vfi.or.at
 *
 * 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 net.coalevo.bot.knsu.impl;

import net.coalevo.bot.knsu.service.KnsuBotConfiguration;
import net.coalevo.bot.knsu.service.KnsuBotService;
import net.coalevo.foundation.model.*;
import net.coalevo.foundation.util.ConfigurationUpdateHandler;
import net.coalevo.foundation.util.LRUCacheMap;
import net.coalevo.foundation.util.metatype.MetaTypeDictionary;
import net.coalevo.foundation.util.metatype.MetaTypeDictionaryException;
import net.coalevo.messaging.model.*;
import net.coalevo.messaging.service.MessagingService;
import net.coalevo.presence.model.AgentIdentifierList;
import net.coalevo.presence.model.PresenceProxy;
import net.coalevo.presence.model.PresenceServiceListenerAdapter;
import net.coalevo.presence.model.ServicePresenceProxy;
import net.coalevo.security.model.ServiceAgentProxy;
import org.osgi.framework.BundleContext;
import org.slf4j.Marker;
import org.slf4j.MarkerFactory;

import java.io.IOException;
import java.net.MalformedURLException;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;

/**
 * This class implements the Knsu Bot as a Service.
 * <p/>
 *
 * @author Dieter Wimberger (wimpi)
 * @version @version@ (@date@)
 */
class KnsuBotServiceImpl
    extends BaseService
    implements KnsuBotService, ConfigurationUpdateHandler {

  private Marker m_LogMarker = MarkerFactory.getMarker(KnsuBotServiceImpl.class.getName());
  private Messages m_BundleMessages;

  //Coalevo Services
  private ServiceMediator m_Services;

  //Security Context
  private ServiceAgentProxy m_ServiceAgentProxy;
  private ServicePresenceProxy m_ServicePresenceProxy;
  private ServiceMessagingProxy m_ServiceMessagingProxy;

  //Presence
  private Set<AgentIdentifier> m_PresentSubscribers;

  //Cache
  private LRUCacheMap<String, KnsuURL> m_URLCache;
  private LRUCacheMap<String, KnsuInfo> m_InfoCache;

  //Client
  private KnsuClient m_KnsuClient;

  KnsuBotServiceImpl() {
    super(KnsuBotService.class.getName(), ACTIONS);
    m_URLCache = new LRUCacheMap<String, KnsuURL>(20);
    m_InfoCache = new LRUCacheMap<String, KnsuInfo>(20);
    m_KnsuClient = new KnsuClient();
  }//constructor

  public boolean activate(BundleContext bc) {
    //1. Services and Messages
    m_Services = Activator.getServices();
    m_BundleMessages = Activator.getBundleMessages();

    //3. Authenticate ourself
    m_ServiceAgentProxy = new ServiceAgentProxy(this, Activator.log());
    m_ServiceAgentProxy.activate(bc);

    //4. Presence Handling
    m_PresentSubscribers = new HashSet<AgentIdentifier>();
    m_ServicePresenceProxy = new ServicePresenceProxy(
        new PresenceListenerImpl(),
        m_ServiceAgentProxy,
        Activator.log());
    m_ServicePresenceProxy.activate(bc);

    //5. Messaging Handling
    m_ServiceMessagingProxy = new ServiceMessagingProxy(
        new MessagingServiceListenerImpl(),
        m_ServicePresenceProxy,
        Activator.log()
    );

    //3. Run Presence Subscription task
    m_Services.getExecutionService(ServiceMediator.WAIT_UNLIMITED).execute(this.m_ServiceAgentProxy.getAuthenticPeer(), new Runnable() {
      public void run() {
        try {
          AgentIdentifierList requests = m_ServicePresenceProxy.getPresence().getRequestedSubscriptions();
          for (Iterator<AgentIdentifier> iterator = requests.iterator(); iterator.hasNext();) {
            AgentIdentifier aid = iterator.next();
            m_ServicePresenceProxy.getPresenceService().allowSubscription(m_ServicePresenceProxy.getPresence(), aid);
            m_ServicePresenceProxy.getPresenceService().requestSubscriptionTo(m_ServicePresenceProxy.getPresence(), aid);
          }
        } catch (Exception ex) {
          Activator.log().error(m_LogMarker, "activate()", ex);
        }
      }//run
    });
    m_ServiceMessagingProxy.activate(bc);

    //2. Handle configuration
    update(m_Services.getConfigMediator().getConfiguration());
    m_Services.getConfigMediator().addUpdateHandler(this);

    return true;
  }//activate

  public boolean deactivate() {
    if (m_ServiceMessagingProxy != null) {
      m_ServiceMessagingProxy.deactivate();
      m_ServiceMessagingProxy = null;
    }
    if (m_ServicePresenceProxy != null) {
      m_ServicePresenceProxy.deactivate();
      m_ServicePresenceProxy = null;
    }
    if (m_ServiceAgentProxy != null) {
      m_ServiceAgentProxy.deactivate();
      m_ServiceAgentProxy = null;
    }
    if (m_URLCache != null) {
      m_URLCache.clear();
    }
    if (m_InfoCache != null) {
      m_InfoCache.clear();
    }
    m_Services = null;
    return true;
  }//deactivate

  public void update(MetaTypeDictionary mtd) {
    //1. Configure from persistent configuration
    int urlcsize = 20;
    int infocsize = 20;
    String login = "";
    String apikey = "";

    //Retrieve config
    try {
      login = mtd.getString(KnsuBotConfiguration.KNSU_LOGIN_KEY);
    } catch (MetaTypeDictionaryException ex) {
      Activator.log().error(m_LogMarker,
          m_BundleMessages.get("KnsuBotServiceImpl.activation.configexception", "attribute", KnsuBotConfiguration.KNSU_LOGIN_KEY),
          ex
      );
    }
    try {
      apikey = mtd.getString(KnsuBotConfiguration.KNSU_APIKEY_KEY);
    } catch (MetaTypeDictionaryException ex) {
      Activator.log().error(m_LogMarker,
          m_BundleMessages.get("KnsuBotServiceImpl.activation.configexception", "attribute", KnsuBotConfiguration.KNSU_APIKEY_KEY),
          ex
      );
    }
    try {
      urlcsize = mtd.getInteger(KnsuBotConfiguration.KNSU_URLCACHESIZE_KEY).intValue();
    } catch (MetaTypeDictionaryException ex) {
      Activator.log().error(m_LogMarker,
          m_BundleMessages.get("KnsuBotServiceImpl.activation.configexception", "attribute", KnsuBotConfiguration.KNSU_URLCACHESIZE_KEY),
          ex
      );
    }
    try {
      infocsize = mtd.getInteger(KnsuBotConfiguration.KNSU_URLCACHESIZE_KEY).intValue();
    } catch (MetaTypeDictionaryException ex) {
      Activator.log().error(m_LogMarker,
          m_BundleMessages.get("KnsuBotServiceImpl.activation.configexception", "attribute", KnsuBotConfiguration.KNSU_URLCACHESIZE_KEY),
          ex
      );
    }

    //Update config
    m_KnsuClient.setAuthentication(login, apikey);

    //Update cache setting
    m_URLCache.setCeiling(urlcsize);
    m_InfoCache.setCeiling(infocsize);

  }//update

  private void sendMessage(AgentIdentifier to, String content, String format) {
    try {
      MessagingService ms = m_ServiceMessagingProxy.getMessagingService();

      EditableInteractiveMessage im = ms.create(
          m_ServicePresenceProxy.getPresence(),
          InteractiveMessageTypes.CHAT,
          m_Services.getUUIDGeneratorService(ServiceMediator.NO_WAIT).getUID()
      );
      im.setTo(to);
      im.setBody(content);
      im.setConfirmationRequired(false);
      if (format != null && format.length() > 0) {
        im.setFormattingHint(format);
      }
      ms.send(m_ServicePresenceProxy.getPresence(), im);

    } catch (Exception mex) {
      Activator.log().error(m_LogMarker, "sendMessage()", mex);
    }
  }//sendMessage


  //** Command Implementations **//

  private void doHelp(AgentIdentifier aid) {
    sendMessage(aid, m_BundleMessages.get("KnsuBotServiceImpl.bot.help"), FORMAT_TML);
  }//doHelp

  private void doShorten(AgentIdentifier aid, String url) {
    String msg;
    try {
      KnsuURL bu = m_KnsuClient.shorten(url);
      if (bu.notError()) {
        msg = m_BundleMessages.get("KnsuBotServiceImpl.bot.shortened", "long", bu.getLong(), "short", bu.getShort());
      } else {
        msg = m_BundleMessages.get(
            "KnsuBotServiceImpl.bot.knsuerror",
            "code", Integer.toString(bu.getError()),
            "msg", bu.getErrorMessage()
        );
      }
    } catch (MalformedURLException muex) {
      msg = m_BundleMessages.get("KnsuBotServiceImpl.bot.malformedurl");
    } catch (IOException ex) {
      msg = m_BundleMessages.get("KnsuBotServiceImpl.bot.iofailed");
    }
    sendMessage(aid, msg, FORMAT_TML);
  }//doShorten

  private void doExpand(AgentIdentifier aid, String str) {
    String msg;
    KnsuURL bu = null;
    try {
      //check cache
      if (str.startsWith("http://")) {
        String hash = str.substring(str.lastIndexOf('/') + 1);
        bu = m_URLCache.get(hash);
      }
      if (bu == null) {
        bu = m_KnsuClient.expand(str);
      }
      if (bu.notError()) {
        m_URLCache.put(bu.getTag(),bu);
        msg = m_BundleMessages.get("KnsuBotServiceImpl.bot.expanded", "long", bu.getLong(), "short", bu.getShort());
      } else {
        msg = m_BundleMessages.get(
            "KnsuBotServiceImpl.bot.knsuerror",
            "code", Integer.toString(bu.getError()),
            "msg", bu.getErrorMessage()
        );
      }
    } catch (MalformedURLException muex) {
      msg = m_BundleMessages.get("KnsuBotServiceImpl.bot.malformedurl");
    } catch (IOException ex) {
      msg = m_BundleMessages.get("KnsuBotServiceImpl.bot.iofailed");
    }
    sendMessage(aid, msg, FORMAT_TML);
  }//doExpand

  private void doInfo(AgentIdentifier aid, String str) {
    String msg;
    KnsuInfo bi = null;
    try {
      //check cache
      if (str.startsWith("http://")) {
        String hash = str.substring(str.lastIndexOf('/') + 1);
        bi = m_InfoCache.get(hash);
      }
      if (bi == null) {
        bi = m_KnsuClient.info(str);
        //System.out.println(bi.toString());
      }
      if (bi.notError()) {
        m_InfoCache.put(bi.getTag(), bi);
        MessageAttributes attr = m_BundleMessages.leaseAttributes();
        attr.add("tag", bi.getTag());
        attr.add("short", bi.getShort());
        attr.add("long", bi.getLong());
        attr.add("longenc", KnsuClient.encodeURL(bi.getLong()));
        addIf(attr, "title", bi.getTitle());
        addIf(attr, "desc", bi.getDescription());
        addIf(attr, "keywords", bi.getKeywordsAsString());
        addIf(attr, "shortenuser", bi.getShortenUser());
        addIf(attr, "when", bi.getWhen());
        msg = m_BundleMessages.get("KnsuBotServiceImpl.bot.urlinfo", attr);
        //System.out.println("Got message " + msg);
      } else {
        msg = m_BundleMessages.get(
            "KnsuBotServiceImpl.bot.knsuerror",
            "code", Integer.toString(bi.getError()),
            "msg", bi.getErrorMessage()
        );
      }
    } catch (MalformedURLException muex) {
      msg = m_BundleMessages.get("KnsuBotServiceImpl.bot.malformedurl");
    } catch (IOException ex) {
      msg = m_BundleMessages.get("KnsuBotServiceImpl.bot.iofailed");
    }
    sendMessage(aid, msg, FORMAT_TML);
  }//doInfo

  private void addIf(MessageAttributes attr, String key, String val) {
    if(val != null && val.trim().length() > 0) {
      attr.add(key, val);
    }
  }//addIf

  private void doStats(AgentIdentifier aid, String str) {
    String msg;
    KnsuStats bs = null;
    try {
      bs = m_KnsuClient.stats(str);
      if (bs.notError()) {
        MessageAttributes attr = m_BundleMessages.leaseAttributes();
        attr.add("tag", bs.getTag());
        attr.add("short", bs.getShort());
        attr.add("clicks", Long.toString(bs.getClicks()));
        msg = m_BundleMessages.get("KnsuBotServiceImpl.bot.urlstats", attr);
      } else {
        msg = m_BundleMessages.get(
            "KnsuBotServiceImpl.bot.knsuerror",
            "code", Integer.toString(bs.getError()),
            "msg", bs.getErrorMessage()
        );
      }
    } catch (MalformedURLException muex) {
      msg = m_BundleMessages.get("KnsuBotServiceImpl.bot.malformedurl");
    } catch (IOException ex) {
      msg = m_BundleMessages.get("KnsuBotServiceImpl.bot.iofailed");
    }
    sendMessage(aid, msg, FORMAT_TML);
  }//doStats

  class PresenceListenerImpl
      extends PresenceServiceListenerAdapter {

    public void found(PresenceProxy p) {
      if (p.isAvailable()) {
        handlePresence(p.getAgentIdentifier());
      } else {
        handleAbsence(p.getAgentIdentifier());
      }
    }//found

    public void receivedPresence(PresenceProxy p) {
      if (p.isAvailable()) {
        handlePresence(p.getAgentIdentifier());
      } else {
        handleAbsence(p.getAgentIdentifier());
      }
    }//receivedPresence

    public void becamePresent(PresenceProxy p) {
      handlePresence(p.getAgentIdentifier());
    }//becamePresent

    public void becameAbsent(PresenceProxy p) {
      handleAbsence(p.getAgentIdentifier());
    }//becameAbsent

    public void statusUpdated(PresenceProxy p) {
      if (p.isAvailable()) {
        handlePresence(p.getAgentIdentifier());
      } else {
        handleAbsence(p.getAgentIdentifier());
      }
    }//statusUpdated

    public void subscriptionCanceled(final AgentIdentifier aid) {
      // unregister(aid);
    }//subscriptionCanceled

    public void subscriptionAllowed(final AgentIdentifier aid) {
      m_Services.getExecutionService(ServiceMediator.NO_WAIT).execute(KnsuBotServiceImpl.this.m_ServiceAgentProxy.getAuthenticPeer(), new Runnable() {
        public void run() {
          m_ServicePresenceProxy.getPresenceService().requestSubscriptionTo(
              m_ServicePresenceProxy.getPresence(),
              aid
          );
        }//run
      }//runnable
      );//execute
    }//subscriptionAllowed

    public void requestedSubscription(PresenceProxy p) {
      final AgentIdentifier aid = p.getAgentIdentifier();
      m_Services.getExecutionService(ServiceMediator.NO_WAIT).execute(KnsuBotServiceImpl.this.m_ServiceAgentProxy.getAuthenticPeer(), new Runnable() {
        public void run() {
          m_ServicePresenceProxy.getPresenceService().allowSubscription(
              m_ServicePresenceProxy.getPresence(),
              aid
          );
          m_ServicePresenceProxy.getPresenceService().requestSubscriptionTo(
              m_ServicePresenceProxy.getPresence(),
              aid
          );
        }//run
      }//runnable
      );//execute
    }//requestedSubscription

    protected void handlePresence(final AgentIdentifier aid) {
      m_Services.getExecutionService(ServiceMediator.NO_WAIT).execute(KnsuBotServiceImpl.this.m_ServiceAgentProxy.getAuthenticPeer(), new Runnable() {
        public void run() {
          //subcriber logic
          if (m_PresentSubscribers.contains(aid)) {
            return;
          } else {
            m_PresentSubscribers.add(aid);
          }
        }//run
      }//runnable
      );//execute
    }//handlePresence

    protected void handleAbsence(final AgentIdentifier aid) {
      m_Services.getExecutionService(ServiceMediator.NO_WAIT).execute(KnsuBotServiceImpl.this.m_ServiceAgentProxy.getAuthenticPeer(), new Runnable() {
        public void run() {
          if (!m_PresentSubscribers.remove(aid)) {
            return;
          }
        }//run
      }//runnable
      );//execute
    }//handleAbsence

  }//PresenceListenerImpl

  class MessagingServiceListenerImpl
      extends MessagingServiceListenerAdapter {

    public boolean received(final InteractiveMessage m) {
      m_Services.getExecutionService(ServiceMediator.NO_WAIT).execute(KnsuBotServiceImpl.this.m_ServiceAgentProxy.getAuthenticPeer(), new Runnable() {
        public void run() {
          EventInfo evinf = m.getEventInfo();
          //1. Confirmation
          if (m.isConfirmationRequired()) {
            try {
              m_ServiceMessagingProxy.getMessagingService().confirm(m_ServicePresenceProxy.getPresence(),
                  evinf
              );
            } catch (MessagingException ex) {
              Activator.log().error(m_LogMarker, "MessagingServiceListener:received()", ex);
            }
          }
          //2. Skip Broadcasts
          if(m.isBroadcast()) {
            return;
          }
          //3. Interpret content
          String str = m.getBody();
          if (str != null && str.length() > 0) {
            if (str.startsWith(KNSU_CMD_HELP)) {
              doHelp(m.getFrom());
            } else if (str.startsWith(KNSU_CMD_SHORTEN)) {
              doShorten(m.getFrom(), str.substring(KNSU_CMD_SHORTEN.length()).trim());
            } else if (str.startsWith(KNSU_CMD_EXPAND)) {
              doExpand(m.getFrom(), str.substring(KNSU_CMD_EXPAND.length()).trim());
            } else if (str.startsWith(KNSU_URL)) {
              doInfo(m.getFrom(),str.trim());
            } else if (str.startsWith(ANY_URL)) {
              doShorten(m.getFrom(), str.trim());
            } else if (str.startsWith(KNSU_CMD_INFO)) {
              doInfo(m.getFrom(), str.substring(KNSU_CMD_INFO.length()).trim());
            } else if (str.startsWith(KNSU_CMD_STATS)) {
              doStats(m.getFrom(), str.substring(KNSU_CMD_STATS.length()).trim());
            } else {
              sendMessage(m.getFrom(), m_BundleMessages.get("KnsuBotServiceImpl.bot.nosuchcmd", "cmd", str.trim()), FORMAT_TML);
            }
          }
        }//run
      }//runnable
      );//execute
      return true;
    }//received

  }//MessagingServiceListenerImpl

  private static Action[] ACTIONS = {};

  private static final String KNSU_CMD_HELP = "help";
  private static final String KNSU_CMD_SHORTEN = "shorten";
  private static final String KNSU_CMD_EXPAND = "expand";
  private static final String KNSU_CMD_INFO = "info";
  private static final String KNSU_CMD_STATS = "stats";
  private static final String KNSU_URL = "http://karanet.at/r";
  private static final String ANY_URL = "http://";

  private static final String FORMAT_TML = "tml";

}//class KnsuBotServiceImpl