/*
 *  The Mana World Server
 *  Copyright 2004 The Mana World Development Team
 *
 *  This file is part of The Mana World.
 *
 *  The Mana World is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  any later version.
 *
 *  The Mana World is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with The Mana World; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 *  $Id$
 */

#include "account-server/accounthandler.hpp"

#include "defines.h"
#include "configuration.h"
#include "point.h"
#include "account-server/account.hpp"
#include "account-server/accountclient.hpp"
#include "account-server/characterdata.hpp"
#include "account-server/guild.hpp"
#include "account-server/guildmanager.hpp"
#include "account-server/serverhandler.hpp"
#include "account-server/storage.hpp"
#include "chat-server/chathandler.hpp"
#include "net/connectionhandler.hpp"
#include "net/messagein.hpp"
#include "net/messageout.hpp"
#include "net/netcomputer.hpp"
#include "utils/logger.h"
#include "utils/stringfilter.h"
#include "utils/tokencollector.hpp"
#include "utils/tokendispenser.hpp"

AccountHandler::AccountHandler():
    mTokenCollector(this)
{
}

bool
AccountHandler::startListen(enet_uint16 port)
{
    LOG_INFO("Account handler started:");
    return ConnectionHandler::startListen(port);
}

NetComputer*
AccountHandler::computerConnected(ENetPeer *peer)
{
    return new AccountClient(peer);
}

void
AccountHandler::computerDisconnected(NetComputer *comp)
{
    AccountClient* computer = static_cast< AccountClient * >(comp);

    if (computer->status == CLIENT_QUEUED)
        // Delete it from the pendingClient list
        mTokenCollector.deletePendingClient(computer);

    delete computer; // ~AccountClient unsets the account
}

/**
 * Generic interface convention for getting a message and sending it to the
 * correct subroutines. Account handler takes care of determining the
 * current step in the account process, be it creation, setup, or login.
 */
void
AccountHandler::processMessage(NetComputer *comp, MessageIn &message)
{
    AccountClient &computer = *static_cast< AccountClient * >(comp);

    switch (message.getId())
    {
        case PAMSG_LOGIN:
            LOG_DEBUG("Received msg ... PAMSG_LOGIN");
            handleLoginMessage(computer, message);
            break;

        case PAMSG_LOGOUT:
            LOG_DEBUG("Received msg ... PAMSG_LOGOUT");
            handleLogoutMessage(computer);
            break;

        case PAMSG_RECONNECT:
            LOG_DEBUG("Received msg ... PAMSG_RECONNECT");
            handleReconnectMessage(computer, message);
            break;

        case PAMSG_REGISTER:
            LOG_DEBUG("Received msg ... PAMSG_REGISTER");
            handleRegisterMessage(computer, message);
            break;

        case PAMSG_UNREGISTER:
            LOG_DEBUG("Received msg ... PAMSG_UNREGISTER");
            handleUnregisterMessage(computer, message);
            break;

        case PAMSG_EMAIL_CHANGE:
            LOG_DEBUG("Received msg ... PAMSG_EMAIL_CHANGE");
            handleEmailChangeMessage(computer, message);
            break;

        case PAMSG_EMAIL_GET:
            LOG_DEBUG("Received msg ... PAMSG_EMAIL_GET");
            handleEmailGetMessage(computer);
            break;

        case PAMSG_PASSWORD_CHANGE:
            LOG_DEBUG("Received msg ... PAMSG_PASSWORD_CHANGE");
            handlePasswordChangeMessage(computer, message);
            break;

        case PAMSG_CHAR_CREATE:
            LOG_DEBUG("Received msg ... PAMSG_CHAR_CREATE");
            handleCharacterCreateMessage(computer, message);
            break;

        case PAMSG_CHAR_SELECT:
            LOG_DEBUG("Received msg ... PAMSG_CHAR_SELECT");
            handleCharacterSelectMessage(computer, message);
            break;

        case PAMSG_CHAR_DELETE:
            LOG_DEBUG("Received msg ... PAMSG_CHAR_DELETE");
            handleCharacterDeleteMessage(computer, message);
            break;

        default:
            LOG_WARN("AccountHandler::processMessage, Invalid message type "
                     << message.getId());
            MessageOut result(XXMSG_INVALID);
            computer.send(result);
            break;
    }
}

void
AccountHandler::handleLoginMessage(AccountClient &computer, MessageIn &msg)
{
    MessageOut reply(APMSG_LOGIN_RESPONSE);

    if (computer.status != CLIENT_LOGIN)
    {
        reply.writeByte(ERRMSG_FAILURE);
        computer.send(reply);
        return;
    }

    unsigned long clientVersion = msg.readLong();

    if (clientVersion < config.getValue("clientVersion", 0))
    {
        reply.writeByte(LOGIN_INVALID_VERSION);
        computer.send(reply);
        return;
    }

    std::string username = msg.readString();
    std::string password = msg.readString();

    if (stringFilter->findDoubleQuotes(username))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
        computer.send(reply);
        return;
    }

    if (getClientNumber() >= MAX_CLIENTS )
    {
        reply.writeByte(LOGIN_SERVER_FULL);
        computer.send(reply);
        return;
    }

    // Check if the account exists
    Storage &store = Storage::instance("tmw");
    AccountPtr acc = store.getAccount(username);

    if (!acc.get() || acc->getPassword() != password)
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
        computer.send(reply);
        return;
    }

    // Associate account with connection
    computer.setAccount(acc);
    computer.status = CLIENT_CONNECTED;

    reply.writeByte(ERRMSG_OK);
    computer.send(reply); // Acknowledge login

    // Return information about available characters
    Characters &chars = computer.getAccount()->getCharacters();

    // Send characters list
    for (unsigned int i = 0; i < chars.size(); i++)
    {
        MessageOut charInfo(APMSG_CHAR_INFO);
        charInfo.writeByte(i); // Slot
        charInfo.writeString(chars[i]->getName());
        charInfo.writeByte((unsigned char) chars[i]->getGender());
        charInfo.writeByte(chars[i]->getHairStyle());
        charInfo.writeByte(chars[i]->getHairColor());
        charInfo.writeByte(chars[i]->getLevel());
        charInfo.writeLong(chars[i]->getMoney());

        for (int j = 0; j < NB_BASE_ATTRIBUTES; ++j)
            charInfo.writeShort(chars[i]->getBaseAttribute(j));

        computer.send(charInfo);
    }
    return;
}

void
AccountHandler::handleLogoutMessage(AccountClient &computer)
{
    MessageOut reply(APMSG_LOGOUT_RESPONSE);

    if (computer.status == CLIENT_LOGIN)
    {
        reply.writeByte(ERRMSG_NO_LOGIN);
    }
    else if (computer.status == CLIENT_CONNECTED)
    {
        computer.unsetAccount();
        computer.status = CLIENT_LOGIN;
        reply.writeByte(ERRMSG_OK);
    }
    else if (computer.status == CLIENT_QUEUED)
    {
        // Delete it from the pendingClient list
        mTokenCollector.deletePendingClient(&computer);
        // deletePendingClient makes sure that the client get's the message
        return;
    }
    computer.send(reply);
}

void AccountHandler::
handleReconnectMessage(AccountClient &computer, MessageIn &msg)
{
    if (computer.status != CLIENT_LOGIN)
    {
        LOG_DEBUG("Account tried to reconnect, but was already logged in "
                 << "or queued.");
        return;
    }

    std::string magic_token = msg.readString(MAGIC_TOKEN_LENGTH);
    computer.status = CLIENT_QUEUED; // Before the addPendingClient
    mTokenCollector.addPendingClient(magic_token, &computer);
}

void
AccountHandler::handleRegisterMessage(AccountClient &computer, MessageIn &msg)
{
    unsigned long clientVersion = msg.readLong();
    std::string username = msg.readString();
    std::string password = msg.readString();
    std::string email = msg.readString();

    MessageOut reply(APMSG_REGISTER_RESPONSE);

    if (computer.status != CLIENT_LOGIN)
    {
        reply.writeByte(ERRMSG_FAILURE);
    }
    else if (clientVersion < config.getValue("clientVersion", 0))
    {
        reply.writeByte(REGISTER_INVALID_VERSION);
    }
    else if (stringFilter->findDoubleQuotes(username))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
    }
    else if (stringFilter->findDoubleQuotes(email))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
    }
    else if ((username.length() < MIN_LOGIN_LENGTH) ||
            (username.length() > MAX_LOGIN_LENGTH))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
    }
    else if ((password.length() < MIN_PASSWORD_LENGTH) ||
            (password.length() > MAX_PASSWORD_LENGTH))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
    }
    else if (!stringFilter->isEmailValid(email))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
    }
    // Checking if the Name is slang's free.
    else if (!stringFilter->filterContent(username))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
    }
    else
    {
        Storage &store = Storage::instance("tmw");
        AccountPtr accPtr = store.getAccount(username);

        // Check whether the account already exists.
        if (accPtr.get())
        {
            reply.writeByte(REGISTER_EXISTS_USERNAME);
        }
        // Find out whether the email is already in use.
        else if (store.doesEmailAddressExist(email))
        {
            reply.writeByte(REGISTER_EXISTS_EMAIL);
        }
        else
        {
            AccountPtr acc(new Account(username, password, email));
            store.addAccount(acc);
            reply.writeByte(ERRMSG_OK);

            // Associate account with connection
            computer.setAccount(acc);
            computer.status = CLIENT_CONNECTED;
        }
    }

    computer.send(reply);
}

void
AccountHandler::handleUnregisterMessage(AccountClient &computer,
                                        MessageIn &msg)
{
    LOG_DEBUG("AccountHandler::handleUnregisterMessage");
    std::string username = msg.readString();
    std::string password = msg.readString();

    MessageOut reply(APMSG_UNREGISTER_RESPONSE);

    if (computer.status != CLIENT_LOGIN)
    {
        reply.writeByte(ERRMSG_FAILURE);
        computer.send(reply);
        return;
    }

    if (stringFilter->findDoubleQuotes(username))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
        computer.send(reply);
        return;
    }

    // See if the account exists
    Storage &store = Storage::instance("tmw");
    AccountPtr accPtr = store.getAccount(username);

    if (!accPtr.get() || accPtr->getPassword() != password)
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
        computer.send(reply);
        return;
    }

    // Delete account and associated characters
    LOG_DEBUG("Unregistered \"" << username
              << "\", AccountID: " << accPtr->getID());
    store.delAccount(accPtr);
    reply.writeByte(ERRMSG_OK);

    // If the account to delete is the current account we're loggedin
    // on, get out of it in memory.
    if (computer.getAccount().get() != NULL &&
                                 computer.getAccount()->getName() == username)
    {
        computer.unsetAccount();
        computer.status = CLIENT_LOGIN;
    }
    computer.send(reply);
}

void AccountHandler::
handleEmailChangeMessage(AccountClient &computer, MessageIn &msg)
{
    MessageOut reply(APMSG_EMAIL_CHANGE_RESPONSE);

    if (computer.status != CLIENT_CONNECTED ||
        computer.getAccount().get() == NULL)
    {
        reply.writeByte(ERRMSG_NO_LOGIN);
        computer.send(reply);
        return;
    }

    std::string email = msg.readString();

    Storage &store = Storage::instance("tmw");

    if (!stringFilter->isEmailValid(email))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
    }
    else if (stringFilter->findDoubleQuotes(email))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
    }
    else if (store.doesEmailAddressExist(email))
    {
        reply.writeByte(EMAILCHG_EXISTS_EMAIL);
    }
    else
    {
        computer.getAccount()->setEmail(email);
        reply.writeByte(ERRMSG_OK);
    }
    computer.send(reply);
}

void AccountHandler::
handleEmailGetMessage(AccountClient &computer)
{
    MessageOut reply(APMSG_EMAIL_GET_RESPONSE);

    if (computer.status != CLIENT_CONNECTED ||
        computer.getAccount().get() == NULL)
    {
        reply.writeByte(ERRMSG_NO_LOGIN);
        computer.send(reply);
        return;
    }

    reply.writeByte(ERRMSG_OK);
    reply.writeString(computer.getAccount()->getEmail());

    computer.send(reply);
}

void
AccountHandler::handlePasswordChangeMessage(AccountClient &computer,
                                            MessageIn &msg)
{
    std::string oldPassword = msg.readString();
    std::string newPassword = msg.readString();

    MessageOut reply(APMSG_PASSWORD_CHANGE_RESPONSE);

    if (computer.status != CLIENT_CONNECTED ||
        computer.getAccount().get() == NULL)
    {
        reply.writeByte(ERRMSG_NO_LOGIN);
    }
    else if (newPassword.length() < MIN_PASSWORD_LENGTH ||
            newPassword.length() > MAX_PASSWORD_LENGTH)
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
    }
    else if (stringFilter->findDoubleQuotes(newPassword))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
    }
    else if (oldPassword != computer.getAccount()->getPassword())
    {
        reply.writeByte(ERRMSG_FAILURE);
    }
    else
    {
        computer.getAccount()->setPassword(newPassword);
        reply.writeByte(ERRMSG_OK);
    }

    computer.send(reply);
}

void
AccountHandler::handleCharacterCreateMessage(AccountClient &computer,
                                             MessageIn &msg)
{
    std::string name = msg.readString();
    int hairStyle = msg.readByte();
    int hairColor = msg.readByte();
    int gender = msg.readByte();

    MessageOut reply(APMSG_CHAR_CREATE_RESPONSE);

    if (computer.status != CLIENT_CONNECTED ||
        computer.getAccount().get() == NULL)
    {
        reply.writeByte(ERRMSG_NO_LOGIN);
    }
    else if (!stringFilter->filterContent(name))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
    }
    else if (stringFilter->findDoubleQuotes(name))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
    }
    else if (hairStyle < 0 || hairStyle > MAX_HAIRSTYLE_VALUE)
    {
        reply.writeByte(CREATE_INVALID_HAIRSTYLE);
    }
    else if (hairColor < 0 || hairColor > MAX_HAIRCOLOR_VALUE)
    {
        reply.writeByte(CREATE_INVALID_HAIRCOLOR);
    }
    else if (gender < 0 || gender > MAX_GENDER_VALUE)
    {
        reply.writeByte(CREATE_INVALID_GENDER);
    }
    else if ((name.length() < MIN_CHARACTER_LENGTH) ||
             (name.length() > MAX_CHARACTER_LENGTH))
    {
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
    }
    else
    {
        Storage &store = Storage::instance("tmw");
        if (store.doesCharacterNameExist(name))
        {
            reply.writeByte(CREATE_EXISTS_NAME);
            computer.send(reply);
            return;
        }

        // An account shouldn't have more than MAX_OF_CHARACTERS characters.
        Characters &chars = computer.getAccount()->getCharacters();
        if (chars.size() >= MAX_OF_CHARACTERS)
        {
            reply.writeByte(CREATE_TOO_MUCH_CHARACTERS);
            computer.send(reply);
            return;
        }

        // LATER_ON: Add race, face and maybe special attributes.

        // Customization of character's attributes...
        unsigned short attributes[NB_BASE_ATTRIBUTES];
        for (int i = 0; i < NB_BASE_ATTRIBUTES; ++i)
            attributes[i] = msg.readShort();

        unsigned int totalAttributes = 0;
        bool validNonZeroAttributes = true;
        for (int i = 0; i < NB_BASE_ATTRIBUTES; ++i)
        {
            // For good total attributes check.
            totalAttributes += attributes[i];

            // For checking if all stats are at least > 0
            if (attributes[i] <= 0) validNonZeroAttributes = false;
        }

        if (totalAttributes > POINTS_TO_DISTRIBUTES_AT_LVL1)
        {
            reply.writeByte(CREATE_ATTRIBUTES_TOO_HIGH);
        }
        else if (totalAttributes < POINTS_TO_DISTRIBUTES_AT_LVL1)
        {
            reply.writeByte(CREATE_ATTRIBUTES_TOO_LOW);
        }
        else if (!validNonZeroAttributes)
        {
            reply.writeByte(CREATE_ATTRIBUTES_EQUAL_TO_ZERO);
        }
        else
        {
            CharacterPtr newCharacter(new CharacterData(name));
            for (int i = 0; i < NB_BASE_ATTRIBUTES; ++i)
                newCharacter->setBaseAttribute(i, attributes[i]);
            newCharacter->setMoney(0);
            newCharacter->setLevel(1);
            newCharacter->setGender(gender);
            newCharacter->setHairStyle(hairStyle);
            newCharacter->setHairColor(hairColor);
            newCharacter->setMapId((int) config.getValue("defaultMap", 1));
            Point startingPos((int) config.getValue("startX", 512),
                                  (int) config.getValue("startY", 512));
            newCharacter->setPosition(startingPos);
            computer.getAccount()->addCharacter(newCharacter);

            LOG_INFO("Character " << name << " was created for "
                     << computer.getAccount()->getName() << "'s account.");

            store.flush(computer.getAccount()); // flush changes
            reply.writeByte(ERRMSG_OK);
            computer.send(reply);

            // Send new characters infos back to client
            MessageOut charInfo(APMSG_CHAR_INFO);
            int slot = chars.size() - 1;
            charInfo.writeByte(slot);
            charInfo.writeString(chars[slot]->getName());
            charInfo.writeByte((unsigned char) chars[slot]->getGender());
            charInfo.writeByte(chars[slot]->getHairStyle());
            charInfo.writeByte(chars[slot]->getHairColor());
            charInfo.writeByte(chars[slot]->getLevel());
            charInfo.writeShort(chars[slot]->getMoney());
            for (int j = 0; j < NB_BASE_ATTRIBUTES; ++j)
                charInfo.writeShort(chars[slot]->getBaseAttribute(j));
            computer.send(charInfo);
            return;
        }
    }

    computer.send(reply);
}

void AccountHandler::
handleCharacterSelectMessage(AccountClient &computer, MessageIn &msg)
{
    MessageOut reply(APMSG_CHAR_SELECT_RESPONSE);

    if (computer.status != CLIENT_CONNECTED ||
        computer.getAccount().get() == NULL)
    {
        reply.writeByte(ERRMSG_NO_LOGIN);
        computer.send(reply);
        return; // not logged in
    }

    unsigned char charNum = msg.readByte();
    Characters &chars = computer.getAccount()->getCharacters();

    // Character ID = 0 to Number of Characters - 1.
    if (charNum >= chars.size())
    {
        // invalid char selection
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
        computer.send(reply);
        return;
    }

    std::string address;
    short port;
    if (!serverHandler->getGameServerFromMap(
                                 chars[charNum]->getMapId(), address, port))
    {
        LOG_ERROR("Character Selection: No game server for the map.");
        reply.writeByte(ERRMSG_FAILURE);
        computer.send(reply);
        return;
    }

    // set character
    computer.setCharacter(chars[charNum]);
    CharacterPtr selectedChar = computer.getCharacter();
    reply.writeByte(ERRMSG_OK);

    LOG_DEBUG(selectedChar->getName() << " is trying to enter the servers.");

    std::string magic_token(utils::getMagicToken());
    reply.writeString(magic_token, MAGIC_TOKEN_LENGTH);
    reply.writeString(address);
    reply.writeShort(port);

    // TODO: get correct address and port for the chat server
    reply.writeString(config.getValue("accountServerAddress", "localhost"));
    reply.writeShort(int(config.getValue("accountServerPort",
                                                   DEFAULT_SERVER_PORT)) + 2);

    serverHandler->registerGameClient(magic_token, selectedChar);
    registerChatClient(magic_token, selectedChar->getName(), AL_NORMAL);

    computer.send(reply);
}

void AccountHandler::
handleCharacterDeleteMessage(AccountClient &computer, MessageIn &msg)
{
    MessageOut reply(APMSG_CHAR_DELETE_RESPONSE);

    if (computer.status != CLIENT_CONNECTED ||
        computer.getAccount().get() == NULL)
    {
        reply.writeByte(ERRMSG_NO_LOGIN);
        computer.send(reply);
        return; // not logged in
    }

    unsigned char charNum = msg.readByte();
    Characters &chars = computer.getAccount()->getCharacters();

    // Character ID = 0 to Number of Characters - 1.
    if (charNum >= chars.size())
    {
        // invalid char selection
        reply.writeByte(ERRMSG_INVALID_ARGUMENT);
        computer.send(reply);
        return; // not logged in
    }

    // Delete the character. If the character to delete is the current
    // character, get off of it in memory.
    if (computer.getCharacter().get() != NULL &&
        computer.getCharacter()->getName() == chars[charNum].get()->getName())
            computer.unsetCharacter();

    std::string deletedCharacter = chars[charNum].get()->getName();
    computer.getAccount()->delCharacter(deletedCharacter);

    Storage &store = Storage::instance("tmw");
    store.flush(computer.getAccount());

    LOG_INFO(deletedCharacter << ": Character deleted...");

    reply.writeByte(ERRMSG_OK);

    computer.send(reply);
}

void
AccountHandler::tokenMatched(AccountClient *computer, int accountID)
{
    MessageOut reply(APMSG_RECONNECT_RESPONSE);

    // Check if the account exists
    Storage &store = Storage::instance("tmw");
    AccountPtr acc = store.getAccountByID(accountID);

    // Associate account with connection
    computer->setAccount(acc);
    computer->status = CLIENT_CONNECTED;

    reply.writeByte(ERRMSG_OK);
    computer->send(reply);

    // Return information about available characters
    Characters &chars = computer->getAccount()->getCharacters();

    // Send characters list
    for (unsigned int i = 0; i < chars.size(); i++)
    {
        MessageOut charInfo(APMSG_CHAR_INFO);
        charInfo.writeByte(i); // Slot
        charInfo.writeString(chars[i]->getName());
        charInfo.writeByte((unsigned char) chars[i]->getGender());
        charInfo.writeByte(chars[i]->getHairStyle());
        charInfo.writeByte(chars[i]->getHairColor());
        charInfo.writeByte(chars[i]->getLevel());
        charInfo.writeShort(chars[i]->getMoney());

        for (int j = 0; j < NB_BASE_ATTRIBUTES; ++j)
        {
            charInfo.writeShort(chars[i]->getBaseAttribute(j));
        }
        computer->send(charInfo);
    }
}

void
AccountHandler::deletePendingClient(AccountClient* computer)
{
    // Something might have changed since it was inserted
    if (computer->status != CLIENT_QUEUED) return;

    MessageOut msg(APMSG_CONNECTION_TIMEDOUT);
    computer->disconnect(msg);
    // The computer will be deleted when the disconnect event is processed
}

void
AccountHandler::deletePendingConnect(int accountID)
{
    // NOOP
    // No memory was allocated for the PendingConnect (that was not
    // allocated to a countedPtr).
}