/*
 * nheko Copyright (C) 2017  Konstantinos Sideris <siderisk@auth.gr>
 *
 * This program 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.
 *
 * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <random>

#include <QApplication>
#include <QDebug>
#include <QFileInfo>
#include <QSettings>

#include "MatrixClient.h"
#include "Sync.h"

#include "timeline/TimelineView.h"
#include "timeline/TimelineViewManager.h"
#include "timeline/widgets/FileItem.h"
#include "timeline/widgets/ImageItem.h"

TimelineViewManager::TimelineViewManager(QSharedPointer<MatrixClient> client, QWidget *parent)
  : QStackedWidget(parent)
  , client_(client)
{
        setStyleSheet("border: none;");

        connect(
          client_.data(), &MatrixClient::messageSent, this, &TimelineViewManager::messageSent);

        connect(client_.data(),
                &MatrixClient::messageSendFailed,
                this,
                &TimelineViewManager::messageSendFailed);
}

TimelineViewManager::~TimelineViewManager() {}

void
TimelineViewManager::messageSent(const QString &event_id, const QString &roomid, int txn_id)
{
        // We save the latest valid transaction ID for later use.
        QSettings settings;
        settings.setValue("client/transaction_id", txn_id + 1);

        auto view = views_[roomid];
        view->updatePendingMessage(txn_id, event_id);
}

void
TimelineViewManager::messageSendFailed(const QString &roomid, int txn_id)
{
        auto view = views_[roomid];
        view->handleFailedMessage(txn_id);
}

void
TimelineViewManager::queueTextMessage(const QString &msg)
{
        auto room_id = active_room_;
        auto view    = views_[room_id];

        view->addUserMessage(matrix::events::MessageEventType::Text, msg);
}

void
TimelineViewManager::queueEmoteMessage(const QString &msg)
{
        auto room_id = active_room_;
        auto view    = views_[room_id];

        view->addUserMessage(matrix::events::MessageEventType::Emote, msg);
}

void
TimelineViewManager::queueImageMessage(const QString &roomid,
                                       const QString &filename,
                                       const QString &url)
{
        if (!views_.contains(roomid)) {
                qDebug() << "Cannot send m.image message to a non-managed view";
                return;
        }

        auto view = views_[roomid];

        view->addUserMessage<ImageItem, matrix::events::MessageEventType::Image>(url, filename);
}

void
TimelineViewManager::queueFileMessage(const QString &roomid,
                                      const QString &filename,
                                      const QString &url)
{
        if (!views_.contains(roomid)) {
                qDebug() << "Cannot send m.file message to a non-managed view";
                return;
        }

        auto view = views_[roomid];

        view->addUserMessage<FileItem, matrix::events::MessageEventType::File>(url, filename);
}

void
TimelineViewManager::clearAll()
{
        for (auto view : views_)
                removeWidget(view.data());

        views_.clear();
}

void
TimelineViewManager::initialize(const Rooms &rooms)
{
        for (auto it = rooms.join().constBegin(); it != rooms.join().constEnd(); ++it) {
                addRoom(it.value(), it.key());
        }
}

void
TimelineViewManager::initialize(const QList<QString> &rooms)
{
        for (const auto &roomid : rooms) {
                addRoom(roomid);
        }
}

void
TimelineViewManager::addRoom(const JoinedRoom &room, const QString &room_id)
{
        // Create a history view with the room events.
        TimelineView *view = new TimelineView(room.timeline(), client_, room_id);
        views_.insert(room_id, QSharedPointer<TimelineView>(view));

        connect(view,
                &TimelineView::updateLastTimelineMessage,
                this,
                &TimelineViewManager::updateRoomsLastMessage);
        connect(view,
                &TimelineView::clearUnreadMessageCount,
                this,
                &TimelineViewManager::clearRoomMessageCount);

        // Add the view in the widget stack.
        addWidget(view);
}

void
TimelineViewManager::addRoom(const QString &room_id)
{
        // Create a history view without any events.
        TimelineView *view = new TimelineView(client_, room_id);
        views_.insert(room_id, QSharedPointer<TimelineView>(view));

        connect(view,
                &TimelineView::updateLastTimelineMessage,
                this,
                &TimelineViewManager::updateRoomsLastMessage);
        connect(view,
                &TimelineView::clearUnreadMessageCount,
                this,
                &TimelineViewManager::clearRoomMessageCount);

        // Add the view in the widget stack.
        addWidget(view);
}

void
TimelineViewManager::sync(const Rooms &rooms)
{
        for (auto it = rooms.join().constBegin(); it != rooms.join().constEnd(); ++it) {
                auto roomid = it.key();

                if (!views_.contains(roomid)) {
                        qDebug() << "Ignoring event from unknown room" << roomid;
                        continue;
                }

                auto view = views_.value(roomid);

                int msgs_added = view->addEvents(it.value().timeline());

                if (msgs_added > 0) {
                        // TODO: When the app window gets active the current
                        // unread count (if any) should be cleared.
                        auto isAppActive = QApplication::activeWindow() != nullptr;

                        if (roomid != active_room_ || !isAppActive)
                                emit unreadMessages(roomid, msgs_added);
                }
        }
}

void
TimelineViewManager::setHistoryView(const QString &room_id)
{
        if (!views_.contains(room_id)) {
                qDebug() << "Room ID from RoomList is not present in ViewManager" << room_id;
                return;
        }

        active_room_ = room_id;
        auto view    = views_.value(room_id);

        setCurrentWidget(view.data());

        view->fetchHistory();
        view->scrollDown();
}

QMap<QString, QString> TimelineViewManager::DISPLAY_NAMES;

QString
TimelineViewManager::chooseRandomColor()
{
        std::random_device random_device;
        std::mt19937 engine{random_device()};
        std::uniform_real_distribution<float> dist(0, 1);

        float hue        = dist(engine);
        float saturation = 0.9;
        float value      = 0.7;

        int hue_i = hue * 6;

        float f = hue * 6 - hue_i;

        float p = value * (1 - saturation);
        float q = value * (1 - f * saturation);
        float t = value * (1 - (1 - f) * saturation);

        float r = 0;
        float g = 0;
        float b = 0;

        if (hue_i == 0) {
                r = value;
                g = t;
                b = p;
        } else if (hue_i == 1) {
                r = q;
                g = value;
                b = p;
        } else if (hue_i == 2) {
                r = p;
                g = value;
                b = t;
        } else if (hue_i == 3) {
                r = p;
                g = q;
                b = value;
        } else if (hue_i == 4) {
                r = t;
                g = p;
                b = value;
        } else if (hue_i == 5) {
                r = value;
                g = p;
                b = q;
        }

        int ri = r * 256;
        int gi = g * 256;
        int bi = b * 256;

        QColor color(ri, gi, bi);

        return color.name();
}

QString
TimelineViewManager::displayName(const QString &userid)
{
        if (DISPLAY_NAMES.contains(userid))
                return DISPLAY_NAMES.value(userid);

        return userid;
}

bool
TimelineViewManager::hasLoaded() const
{
        for (const auto &view : views_)
                if (!view->hasLoaded())
                        return false;

        return true;
}