/*
    Copyright (C) 2020 Sebastian J. Wolf

    This file is part of Fernschreiber.

    Fernschreiber 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 3 of the License, or
    (at your option) any later version.

    Fernschreiber 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 Fernschreiber. If not, see <http://www.gnu.org/licenses/>.
*/

#include "tdlibwrapper.h"
#include "tdlibsecrets.h"
#include <QDir>
#include <QLocale>
#include <QSysInfo>
#include <QSettings>

TDLibWrapper::TDLibWrapper(QObject *parent) : QObject(parent)
{
    qDebug() << "[TDLibWrapper] Initializing TD Lib...";
    this->tdLibClient = td_json_client_create();
    this->tdLibReceiver = new TDLibReceiver(this->tdLibClient, this);

    QString tdLibDatabaseDirectoryPath = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation) + "/tdlib";
    QDir tdLibDatabaseDirectory(tdLibDatabaseDirectoryPath);
    if (!tdLibDatabaseDirectory.exists()) {
        tdLibDatabaseDirectory.mkpath(tdLibDatabaseDirectoryPath);
    }

    connect(this->tdLibReceiver, SIGNAL(versionDetected(QString)), this, SLOT(handleVersionDetected(QString)));
    connect(this->tdLibReceiver, SIGNAL(authorizationStateChanged(QString)), this, SLOT(handleAuthorizationStateChanged(QString)));
    connect(this->tdLibReceiver, SIGNAL(optionUpdated(QString, QVariant)), this, SLOT(handleOptionUpdated(QString, QVariant)));
    connect(this->tdLibReceiver, SIGNAL(connectionStateChanged(QString)), this, SLOT(handleConnectionStateChanged(QString)));
    connect(this->tdLibReceiver, SIGNAL(userUpdated(QVariantMap)), this, SLOT(handleUserUpdated(QVariantMap)));
    connect(this->tdLibReceiver, SIGNAL(fileUpdated(QVariantMap)), this, SLOT(handleFileUpdated(QVariantMap)));
    connect(this->tdLibReceiver, SIGNAL(newChatDiscovered(QVariantMap)), this, SLOT(handleNewChatDiscovered(QVariantMap)));
    connect(this->tdLibReceiver, SIGNAL(unreadMessageCountUpdated(QVariantMap)), this, SLOT(handleUnreadMessageCountUpdated(QVariantMap)));
    connect(this->tdLibReceiver, SIGNAL(unreadChatCountUpdated(QVariantMap)), this, SLOT(handleUnreadChatCountUpdated(QVariantMap)));
    connect(this->tdLibReceiver, SIGNAL(chatLastMessageUpdated(QString, QVariantMap)), this, SLOT(handleChatLastMessageUpdated(QString, QVariantMap)));
    connect(this->tdLibReceiver, SIGNAL(chatOrderUpdated(QString, QString)), this, SLOT(handleChatOrderUpdated(QString, QString)));

    this->tdLibReceiver->start();

    this->setLogVerbosityLevel();
}

TDLibWrapper::~TDLibWrapper()
{
    qDebug() << "[TDLibWrapper] Destroying TD Lib...";
    this->tdLibReceiver->setActive(false);
    while (this->tdLibReceiver->isRunning()) {
        QCoreApplication::processEvents(QEventLoop::AllEvents, 1000);
    }
    td_json_client_destroy(this->tdLibClient);
}

void TDLibWrapper::sendRequest(const QVariantMap &requestObject)
{
    qDebug() << "[TDLibWrapper] Sending request to TD Lib, object type name: " << requestObject.value("@type").toString();
    QJsonDocument requestDocument = QJsonDocument::fromVariant(requestObject);
    td_json_client_send(this->tdLibClient, requestDocument.toJson().constData());
}

QString TDLibWrapper::getVersion()
{
    return this->version;
}

TDLibWrapper::AuthorizationState TDLibWrapper::getAuthorizationState()
{
    return this->authorizationState;
}

TDLibWrapper::ConnectionState TDLibWrapper::getConnectionState()
{
    return this->connectionState;
}

void TDLibWrapper::setAuthenticationPhoneNumber(const QString &phoneNumber)
{
    qDebug() << "[TDLibWrapper] Set authentication phone number " << phoneNumber;
    QVariantMap requestObject;
    requestObject.insert("@type", "setAuthenticationPhoneNumber");
    requestObject.insert("phone_number", phoneNumber);
    QVariantMap phoneNumberSettings;
    phoneNumberSettings.insert("allow_flash_call", false);
    phoneNumberSettings.insert("is_current_phone_number", true);
    requestObject.insert("settings", phoneNumberSettings);
    this->sendRequest(requestObject);
}

void TDLibWrapper::setAuthenticationCode(const QString &authenticationCode)
{
    qDebug() << "[TDLibWrapper] Set authentication code " << authenticationCode;
    QVariantMap requestObject;
    requestObject.insert("@type", "checkAuthenticationCode");
    requestObject.insert("code", authenticationCode);
    this->sendRequest(requestObject);
}

void TDLibWrapper::getChats()
{
    qDebug() << "[TDLibWrapper] Getting chats";
    QVariantMap requestObject;
    requestObject.insert("@type", "getChats");
    requestObject.insert("limit", 5);
    this->sendRequest(requestObject);
}

void TDLibWrapper::downloadFile(const QString &fileId)
{
    qDebug() << "[TDLibWrapper] Downloading file " << fileId;
    QVariantMap requestObject;
    requestObject.insert("@type", "downloadFile");
    requestObject.insert("file_id", fileId);
    requestObject.insert("synchronous", false);
    requestObject.insert("offset", 0);
    requestObject.insert("limit", 0);
    requestObject.insert("priority", 1);
    this->sendRequest(requestObject);
}

QVariantMap TDLibWrapper::getUserInformation()
{
    return this->userInformation;
}

QVariantMap TDLibWrapper::getUserInformation(const QString &userId)
{
    qDebug() << "[TDLibWrapper] Returning user information for ID " << userId;
    return this->allUsers.value(userId).toMap();
}

QVariantMap TDLibWrapper::getUnreadMessageInformation()
{
    return this->unreadMessageInformation;
}

QVariantMap TDLibWrapper::getUnreadChatInformation()
{
    return this->unreadChatInformation;
}

void TDLibWrapper::handleVersionDetected(const QString &version)
{
    this->version = version;
    emit versionDetected(version);
}

void TDLibWrapper::handleAuthorizationStateChanged(const QString &authorizationState)
{
    if (authorizationState == "authorizationStateClosed") {
        this->authorizationState = AuthorizationState::Closed;
    }

    if (authorizationState == "authorizationStateClosing") {
        this->authorizationState = AuthorizationState::Closing;
    }

    if (authorizationState == "authorizationStateLoggingOut") {
        this->authorizationState = AuthorizationState::LoggingOut;
    }

    if (authorizationState == "authorizationStateReady") {
        this->authorizationState = AuthorizationState::AuthorizationReady;
    }

    if (authorizationState == "authorizationStateWaitCode") {
        this->authorizationState = AuthorizationState::WaitCode;
    }

    if (authorizationState == "authorizationStateWaitEncryptionKey") {
        this->setEncryptionKey();
        this->authorizationState = AuthorizationState::WaitEncryptionKey;
    }

    if (authorizationState == "authorizationStateWaitOtherDeviceConfirmation") {
        this->authorizationState = AuthorizationState::WaitOtherDeviceConfirmation;
    }

    if (authorizationState == "authorizationStateWaitPassword") {
        this->authorizationState = AuthorizationState::WaitPassword;
    }

    if (authorizationState == "authorizationStateWaitPhoneNumber") {
        this->authorizationState = AuthorizationState::WaitPhoneNumber;
    }

    if (authorizationState == "authorizationStateWaitRegistration") {
        this->authorizationState = AuthorizationState::WaitRegistration;
    }

    if (authorizationState == "authorizationStateWaitTdlibParameters") {
        this->setInitialParameters();
        this->authorizationState = AuthorizationState::WaitTdlibParameters;
    }

    emit authorizationStateChanged(this->authorizationState);

}

void TDLibWrapper::handleOptionUpdated(const QString &optionName, const QVariant &optionValue)
{
    this->options.insert(optionName, optionValue);
    emit optionUpdated(optionName, optionValue);
    if (optionName == "my_id") {
        emit ownUserIdFound(optionValue.toString());
    }
}

void TDLibWrapper::handleConnectionStateChanged(const QString &connectionState)
{
    if (connectionState == "connectionStateConnecting") {
        this->connectionState = ConnectionState::Connecting;
    }
    if (connectionState == "connectionStateConnectingToProxy") {
        this->connectionState = ConnectionState::ConnectingToProxy;
    }
    if (connectionState == "connectionStateReady") {
        this->connectionState = ConnectionState::ConnectionReady;
    }
    if (connectionState == "connectionStateUpdating") {
        this->connectionState = ConnectionState::Updating;
    }
    if (connectionState == "connectionStateWaitingForNetwork") {
        this->connectionState = ConnectionState::WaitingForNetwork;
    }

    emit connectionStateChanged(this->connectionState);
}

void TDLibWrapper::handleUserUpdated(const QVariantMap &userInformation)
{
    QString updatedUserId = userInformation.value("id").toString();
    if (updatedUserId == this->options.value("my_id").toString()) {
        qDebug() << "[TDLibWrapper] Own user information updated :)";
        this->userInformation = userInformation;
    }
    qDebug() << "[TDLibWrapper] User information updated: " << userInformation.value("username").toString() << userInformation.value("first_name").toString() << userInformation.value("last_name").toString();
    this->allUsers.insert(updatedUserId, userInformation);
}

void TDLibWrapper::handleFileUpdated(const QVariantMap &fileInformation)
{
    emit fileUpdated(fileInformation.value("id").toInt(), fileInformation);
}

void TDLibWrapper::handleNewChatDiscovered(const QVariantMap &chatInformation)
{
    QString chatId = chatInformation.value("id").toString();
    this->chats.insert(chatId, chatInformation);
    emit newChatDiscovered(chatId, chatInformation);
}

void TDLibWrapper::handleUnreadMessageCountUpdated(const QVariantMap &messageCountInformation)
{
    if (messageCountInformation.value("chat_list_type").toString() == "chatListMain") {
        this->unreadMessageInformation = messageCountInformation;
        emit unreadMessageCountUpdated(messageCountInformation);
    }
}

void TDLibWrapper::handleUnreadChatCountUpdated(const QVariantMap &chatCountInformation)
{
    if (chatCountInformation.value("chat_list_type").toString() == "chatListMain") {
        this->unreadChatInformation = chatCountInformation;
        emit unreadChatCountUpdated(chatCountInformation);
    }
}

void TDLibWrapper::handleChatLastMessageUpdated(const QString &chatId, const QVariantMap &lastMessage)
{
    emit chatLastMessageUpdated(chatId, lastMessage);
}

void TDLibWrapper::handleChatOrderUpdated(const QString &chatId, const QString &order)
{
    emit chatOrderUpdated(chatId, order);
}

void TDLibWrapper::setInitialParameters()
{
    qDebug() << "[TDLibWrapper] Sending initial parameters to TD Lib";
    QVariantMap requestObject;
    requestObject.insert("@type", "setTdlibParameters");
    QVariantMap initialParameters;
    initialParameters.insert("api_id", TDLIB_API_ID);
    initialParameters.insert("api_hash", TDLIB_API_HASH);
    initialParameters.insert("database_directory", QStandardPaths::writableLocation(QStandardPaths::AppDataLocation) + "/tdlib");
    initialParameters.insert("use_file_database", true);
    initialParameters.insert("use_chat_info_database", true);
    initialParameters.insert("use_message_database", true);
    initialParameters.insert("use_secret_chats", false);
    initialParameters.insert("system_language_code", QLocale::system().name());
    QSettings hardwareSettings("/etc/hw-release", QSettings::NativeFormat);
    initialParameters.insert("device_model", hardwareSettings.value("NAME", "Unknown Mobile Device").toString());
    initialParameters.insert("system_version", QSysInfo::prettyProductName());
    initialParameters.insert("application_version", "0.1");
    requestObject.insert("parameters", initialParameters);
    this->sendRequest(requestObject);
}

void TDLibWrapper::setEncryptionKey()
{
    qDebug() << "[TDLibWrapper] Setting database encryption key";
    QVariantMap requestObject;
    requestObject.insert("@type", "checkDatabaseEncryptionKey");
    // see https://github.com/tdlib/td/issues/188#issuecomment-379536139
    requestObject.insert("encryption_key", "");
    this->sendRequest(requestObject);
}

void TDLibWrapper::setLogVerbosityLevel()
{
    qDebug() << "[TDLibWrapper] Setting log verbosity level to something less chatty";
    QVariantMap requestObject;
    requestObject.insert("@type", "setLogVerbosityLevel");
    requestObject.insert("new_verbosity_level", 2);
    this->sendRequest(requestObject);
}