#include "widgets/splitcontainer.hpp"
#include "common.hpp"
#include "singletons/thememanager.hpp"
#include "util/helpers.hpp"
#include "util/layoutcreator.hpp"
#include "widgets/helper/notebooktab.hpp"
#include "widgets/notebook.hpp"
#include "widgets/split.hpp"

#include <QApplication>
#include <QDebug>
#include <QHBoxLayout>
#include <QMimeData>
#include <QObject>
#include <QPainter>
#include <QVBoxLayout>
#include <QWidget>
#include <boost/foreach.hpp>

#include <algorithm>

namespace chatterino {
namespace widgets {

bool SplitContainer::isDraggingSplit = false;
Split *SplitContainer::draggingSplit = nullptr;
// SplitContainer::Position SplitContainer::dragOriginalPosition;

SplitContainer::SplitContainer(Notebook *parent, NotebookTab *_tab)
    : BaseWidget(parent)
    , tab(_tab)
    , dropPreview(this)
{
    this->tab->page = this;

    //    this->setLayout(&this->ui.parentLayout);

    //    this->setHidden(true);
    //    this->setAcceptDrops(true);

    //    this->ui.parentLayout.addSpacing(1);
    //    this->ui.parentLayout.addLayout(&this->ui.hbox);
    //    this->ui.parentLayout.setMargin(0);

    //    this->ui.hbox.setSpacing(1);
    //    this->ui.hbox.setMargin(0);

    this->refreshTabTitle();

    this->managedConnect(Split::altPressedStatusChanged, [this](auto) { this->layout(); });

    this->setAcceptDrops(true);
}

NotebookTab *SplitContainer::getTab() const
{
    return this->tab;
}

void SplitContainer::appendNewSplit(bool openChannelNameDialog)
{
    Split *split = new Split(this);
    this->appendSplit(split);

    if (openChannelNameDialog) {
        split->showChangeChannelPopup("Open channel name", true, [=](bool ok) {
            if (!ok) {
                this->deleteSplit(split);
            }
        });
    }
}

void SplitContainer::appendSplit(Split *split)
{
    this->insertSplit(split, Direction::Right);
}

void SplitContainer::insertSplit(Split *split, const Position &position)
{
    this->insertSplit(split, position.direction, position.relativeNode);
}

void SplitContainer::insertSplit(Split *split, Direction direction, Split *relativeTo)
{
    Node *node = this->baseNode.findNodeContainingSplit(relativeTo);
    assert(node != nullptr);

    this->insertSplit(split, direction, node);
}

void SplitContainer::insertSplit(Split *split, Direction direction, Node *relativeTo)
{
    if (relativeTo == nullptr) {
        if (this->baseNode.type == Node::EmptyRoot) {
            this->baseNode.setSplit(split);
        } else if (this->baseNode.type == Node::_Split) {
            this->baseNode.nestSplitIntoCollection(split, direction);
        } else {
            this->baseNode.insertSplitRelative(split, direction);
        }
    } else {
        assert(this->baseNode.isOrContainsNode(relativeTo));

        relativeTo->insertSplitRelative(split, direction);
    }

    split->setParent(this);
    split->show();
    this->splits.push_back(split);

    this->layout();
}

SplitContainer::Position SplitContainer::releaseSplit(Split *split)
{
    Node *node = this->baseNode.findNodeContainingSplit(split);
    assert(node != nullptr);

    this->splits.erase(std::find(this->splits.begin(), this->splits.end(), split));
    split->setParent(nullptr);
    Position position = node->releaseSplit();
    this->layout();
    return position;
}

SplitContainer::Position SplitContainer::deleteSplit(Split *split)
{
    assert(split != nullptr);

    split->deleteLater();
    return releaseSplit(split);
}

void SplitContainer::layout()
{
    this->baseNode.geometry = this->rect();

    std::vector<DropRect> _dropRects;
    this->baseNode.layout(Split::altPressesStatus | this->isDragging, _dropRects);
    _dropRects.clear();
    this->baseNode.layout(Split::altPressesStatus | this->isDragging, _dropRects);

    this->dropRects = std::move(_dropRects);
    this->update();
}

/// EVENTS
void SplitContainer::resizeEvent(QResizeEvent *event)
{
    BaseWidget::resizeEvent(event);

    this->layout();
}

void SplitContainer::mouseReleaseEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton) {
        if (this->splits.size() == 0) {
            // "Add Chat" was clicked
            this->appendNewSplit(true);

            this->setCursor(QCursor(Qt::ArrowCursor));
        } else {
            auto it =
                std::find_if(this->dropRects.begin(), this->dropRects.end(),
                             [event](DropRect &rect) { return rect.rect.contains(event->pos()); });
            if (it != this->dropRects.end()) {
                this->insertSplit(new Split(this), it->position);
            }
        }
    }
}

void SplitContainer::paintEvent(QPaintEvent *)
{
    QPainter painter(this);

    if (this->splits.size() == 0) {
        painter.fillRect(rect(), this->themeManager->splits.background);

        painter.setPen(this->themeManager->splits.header.text);

        QString text = "Click to add a <split>";

        Notebook *notebook = dynamic_cast<Notebook *>(this->parentWidget());

        if (notebook != nullptr) {
            if (notebook->tabCount() > 1) {
                text += "\n\ntip: you can drag a <split> while holding <Alt>";
                text += "\nor add another one by pressing <Ctrl+T>";
            }
        }

        painter.drawText(rect(), text, QTextOption(Qt::AlignCenter));
    } else {
        painter.fillRect(rect(), this->themeManager->splits.messageSeperator);
    }

    for (DropRect &dropRect : this->dropRects) {
        painter.setPen("#774");
        painter.setBrush(QBrush("#553"));

        painter.drawRect(dropRect.rect.marginsRemoved(QMargins(2, 2, 2, 2)));
    }

    QBrush accentColor = (QApplication::activeWindow() == this->window()
                              ? this->themeManager->tabs.selected.backgrounds.regular
                              : this->themeManager->tabs.selected.backgrounds.unfocused);

    painter.fillRect(0, 0, width(), 1, accentColor);
}

void SplitContainer::dragEnterEvent(QDragEnterEvent *event)
{
    if (!event->mimeData()->hasFormat("chatterino/split"))
        return;

    if (!SplitContainer::isDraggingSplit) {
        return;
    }

    this->isDragging = true;
    this->layout();

    event->acceptProposedAction();

    //    this->dropRegions.clear();

    //    if (this->ui.hbox.count() == 0) {
    //        this->dropRegions.push_back(DropRegion(rect(), std::pair<int, int>(-1, -1)));
    //    } else {
    //        for (int i = 0; i < this->ui.hbox.count() + 1; ++i) {
    //            this->dropRegions.push_back(
    //                DropRegion(QRect(((i * 4 - 1) * width() / this->ui.hbox.count()) / 4, 0,
    //                                 width() / this->ui.hbox.count() / 2 + 1, height() + 1),
    //                           std::pair<int, int>(i, -1)));
    //        }

    //        for (int i = 0; i < this->ui.hbox.count(); ++i) {
    //            auto vbox = static_cast<QVBoxLayout *>(this->ui.hbox.itemAt(i));

    //            for (int j = 0; j < vbox->count() + 1; ++j) {
    //                this->dropRegions.push_back(DropRegion(
    //                    QRect(i * width() / this->ui.hbox.count(),
    //                          ((j * 2 - 1) * height() / vbox->count()) / 2,
    //                          width() / this->ui.hbox.count() + 1, height() / vbox->count() + 1),

    //                    std::pair<int, int>(i, j)));
    //            }
    //        }
    //    }

    //    setPreviewRect(event->pos());

    //    event->acceptProposedAction();
}

void SplitContainer::dragMoveEvent(QDragMoveEvent *event)
{
    //    setPreviewRect(event->pos());

    for (auto &dropRect : this->dropRects) {
        if (dropRect.rect.contains(event->pos())) {
            event->acceptProposedAction();
            return;
        }
    }
    event->setAccepted(false);
}

void SplitContainer::dragLeaveEvent(QDragLeaveEvent *event)
{
    this->isDragging = false;
    this->layout();

    //    this->dropPreview.hide();
}

void SplitContainer::dropEvent(QDropEvent *event)
{
    //    if (isDraggingSplit) {
    //        event->acceptProposedAction();

    //        SplitContainer::draggingSplit->setParent(this);

    //        addToLayout(SplitContainer::draggingSplit, dropPosition);
    //    }

    //    this->dropPreview.hide();

    for (auto &dropRect : this->dropRects) {
        if (dropRect.rect.contains(event->pos())) {
            this->insertSplit(SplitContainer::draggingSplit, dropRect.position);
            event->acceptProposedAction();
            break;
        }
    }

    this->isDragging = false;
    this->layout();
}

// void SplitContainer::updateFlexValues()
//{
//    for (int i = 0; i < this->ui.hbox.count(); i++) {
//        QVBoxLayout *vbox = (QVBoxLayout *)ui.hbox.itemAt(i)->layout();

//        if (vbox->count() != 0) {
//            ui.hbox.setStretch(i, (int)(1000 * ((Split *)vbox->itemAt(0))->getFlexSizeX()));
//        }
//    }
//}

// int SplitContainer::splitCount() const
//{
//    return this->splits.size();
//}

// std::pair<int, int> SplitContainer::removeFromLayout(Split *widget)
//{
//    widget->getChannelView().tabHighlightRequested.disconnectAll();

//    // remove reference to chat widget from chatWidgets vector
//    auto it = std::find(std::begin(this->splits), std::end(this->splits), widget);
//    if (it != std::end(this->splits)) {
//        this->splits.erase(it);

//        this->refreshTitle();
//    }

//    Split *neighbouringSplit = nullptr;

//    // Position the split was found at
//    int positionX = -1, positionY = -1;

//    bool removed = false;

//    QVBoxLayout *layoutToRemove = nullptr;

//    // Find widget in box, remove it, return its position
//    for (int i = 0; i < this->ui.hbox.count(); ++i) {
//        auto vbox = static_cast<QVBoxLayout *>(this->ui.hbox.itemAt(i));

//        auto vboxCount = vbox->count();

//        for (int j = 0; j < vboxCount; ++j) {
//            if (vbox->itemAt(j)->widget() != widget) {
//                neighbouringSplit = dynamic_cast<Split *>(vbox->itemAt(j)->widget());

//                if (removed && neighbouringSplit != nullptr) {
//                    // The widget we searched for has been found, and we have a split to switch
//                    // focus to
//                    break;
//                }

//                continue;
//            }

//            removed = true;
//            positionX = i;

//            // Remove split from box
//            widget->setParent(nullptr);

//            if (vbox->count() == 0) {
//                // The split was the last item remaining in the vbox
//                // Remove the vbox once all iteration is done
//                layoutToRemove = vbox;
//                positionY = -1;
//                break;
//            }

//            // Don't break here yet, we want to keep iterating this vbox if possible to find the
//            // closest still-alive neighbour that we can switch focus to
//            positionY = j;

//            --j;
//            --vboxCount;
//        }

//        if (removed && neighbouringSplit != nullptr) {
//            // The widget we searched for has been found, and we have a split to switch focus to
//            break;
//        }
//    }

//    if (removed) {
//        if (layoutToRemove != nullptr) {
//            // The split we removed was the last split in its box. Remove the box
//            // We delay the removing of the box so we can keep iterating over hbox safely
//            this->ui.hbox.removeItem(layoutToRemove);
//            delete layoutToRemove;
//        }

//        if (neighbouringSplit != nullptr) {
//            // We found a neighbour split we can switch focus to
//            neighbouringSplit->giveFocus(Qt::MouseFocusReason);
//        }
//    }

//    return std::make_pair(positionX, positionY);
//}

// void SplitContainer::addToLayout(Split *widget, std::pair<int, int> position)
//{
//    this->splits.push_back(widget);
//    widget->getChannelView().tabHighlightRequested.connect(
//        [this](HighlightState state) { this->tab->setHighlightState(state); });

//    this->refreshTitle();

//    widget->giveFocus(Qt::MouseFocusReason);

//    // add vbox at the end
//    if (position.first < 0 || position.first >= this->ui.hbox.count()) {
//        auto vbox = new QVBoxLayout();
//        vbox->addWidget(widget);

//        this->ui.hbox.addLayout(vbox, 1);

//        this->refreshCurrentFocusCoordinates();
//        return;
//    }

//    // insert vbox
//    if (position.second == -1) {
//        auto vbox = new QVBoxLayout();
//        vbox->addWidget(widget);

//        this->ui.hbox.insertLayout(position.first, vbox, 1);
//        this->refreshCurrentFocusCoordinates();
//        return;
//    }

//    // add to existing vbox
//    auto vbox = static_cast<QVBoxLayout *>(this->ui.hbox.itemAt(position.first));

//    vbox->insertWidget(std::max(0, std::min(vbox->count(), position.second)), widget);

//    this->refreshCurrentFocusCoordinates();
//}

// const std::vector<Split *> &SplitContainer::getSplits() const
//{
//    return this->splits;
//}

// std::vector<std::vector<Split *>> SplitContainer::getColumns() const
//{
//    std::vector<std::vector<Split *>> columns;

//    for (int i = 0; i < this->ui.hbox.count(); i++) {
//        std::vector<Split *> cells;

//        QLayout *vbox = this->ui.hbox.itemAt(i)->layout();
//        for (int j = 0; j < vbox->count(); j++) {
//            cells.push_back(dynamic_cast<Split *>(vbox->itemAt(j)->widget()));
//        }

//        columns.push_back(cells);
//    }

//    return columns;
//}

// void SplitContainer::refreshCurrentFocusCoordinates(bool alsoSetLastRequested)
//{
//    int setX = -1;
//    int setY = -1;
//    bool doBreak = false;
//    for (int x = 0; x < this->ui.hbox.count(); ++x) {
//        QLayoutItem *item = this->ui.hbox.itemAt(x);
//        if (item->isEmpty()) {
//            setX = x;
//            break;
//        }
//        QVBoxLayout *vbox = static_cast<QVBoxLayout *>(item->layout());

//        for (int y = 0; y < vbox->count(); ++y) {
//            QLayoutItem *innerItem = vbox->itemAt(y);

//            if (innerItem->isEmpty()) {
//                setX = x;
//                setY = y;
//                doBreak = true;
//                break;
//            }

//            QWidget *w = innerItem->widget();
//            if (w) {
//                Split *chatWidget = static_cast<Split *>(w);
//                if (chatWidget->hasFocus()) {
//                    setX = x;
//                    setY = y;
//                    doBreak = true;
//                    break;
//                }
//            }
//        }

//        if (doBreak) {
//            break;
//        }
//    }

//    if (setX != -1) {
//        this->currentX = setX;

//        if (setY != -1) {
//            this->currentY = setY;

//            if (alsoSetLastRequested) {
//                this->lastRequestedY[setX] = setY;
//            }
//        }
//    }
//}

// void SplitContainer::requestFocus(int requestedX, int requestedY)
//{
//    // XXX: Perhaps if we request an Y coordinate out of bounds, we shuold set all previously set
//    // requestedYs to 0 (if -1 is requested) or that x-coordinates vbox count (if requestedY >=
//    // currentvbox.count() is requested)
//    if (requestedX < 0 || requestedX >= this->ui.hbox.count()) {
//        return;
//    }

//    QLayoutItem *item = this->ui.hbox.itemAt(requestedX);
//    QWidget *xW = item->widget();
//    if (item->isEmpty()) {
//        qDebug() << "Requested hbox item " << requestedX << "is empty";
//        if (xW) {
//            qDebug() << "but xW is not null";
//            // TODO: figure out what to do here
//        }
//        return;
//    }

//    QVBoxLayout *vbox = static_cast<QVBoxLayout *>(item->layout());

//    if (requestedY < 0) {
//        requestedY = 0;
//    } else if (requestedY >= vbox->count()) {
//        requestedY = vbox->count() - 1;
//    }

//    this->lastRequestedY[requestedX] = requestedY;

//    QLayoutItem *innerItem = vbox->itemAt(requestedY);

//    if (innerItem->isEmpty()) {
//        qDebug() << "Requested vbox item " << requestedY << "is empty";
//        return;
//    }

//    QWidget *w = innerItem->widget();
//    if (w) {
//        Split *chatWidget = static_cast<Split *>(w);
//        chatWidget->giveFocus(Qt::OtherFocusReason);
//    }
//}

// void SplitContainer::enterEvent(QEvent *)
//{
//    if (this->ui.hbox.count() == 0) {
//        this->setCursor(QCursor(Qt::PointingHandCursor));
//    } else {
//        this->setCursor(QCursor(Qt::ArrowCursor));
//    }
//}

// void SplitContainer::leaveEvent(QEvent *)
//{
//}

// void SplitContainer::setPreviewRect(QPoint mousePos)
//{
//    for (DropRegion region : this->dropRegions) {
//        if (region.rect.contains(mousePos)) {
//            this->dropPreview.setBounds(region.rect);

//            if (!this->dropPreview.isVisible()) {
//                this->dropPreview.setGeometry(this->rect());
//                this->dropPreview.show();
//                this->dropPreview.raise();
//            }

//            dropPosition = region.position;

//            return;
//        }
//    }

//    this->dropPreview.hide();
//}

// bool SplitContainer::eventFilter(QObject *object, QEvent *event)
//{
//    if (event->type() == QEvent::FocusIn) {
//        QFocusEvent *focusEvent = static_cast<QFocusEvent *>(event);

//        this->refreshCurrentFocusCoordinates((focusEvent->reason() == Qt::MouseFocusReason));
//    }

//    return false;
//}

// void SplitContainer::showEvent(QShowEvent *event)
//{
//    // Whenever this notebook page is shown, give focus to the last focused chat widget
//    // If this is the first time this notebook page is shown, it will give focus to the
//    top-left
//    // chat widget
//    this->requestFocus(this->currentX, this->currentY);
//}

// static std::pair<int, int> getWidgetPositionInLayout(QLayout *layout, const Split
// *chatWidget)
//{
//    for (int i = 0; i < layout->count(); ++i) {
//        printf("xD\n");
//    }

//    return std::make_pair(-1, -1);
//}

// std::pair<int, int> SplitContainer::getChatPosition(const Split *chatWidget)
//{
//    auto layout = this->ui.hbox.layout();

//    if (layout == nullptr) {
//        return std::make_pair(-1, -1);
//    }

//    return getWidgetPositionInLayout(layout, chatWidget);
//}

// Split *SplitContainer::createChatWidget()
//{
//    auto split = new Split(this);

//    return split;
//}

void SplitContainer::refreshTabTitle()
{
    assert(this->tab != nullptr);

    if (!this->tab->useDefaultTitle) {
        return;
    }

    this->tab->setTitle("default title");

    //    QString newTitle = "";
    //    bool first = true;

    //    for (const auto &chatWidget : this->splits) {
    //        auto channelName = chatWidget->getChannel()->name;
    //        if (channelName.isEmpty()) {
    //            continue;
    //        }

    //        if (!first) {
    //            newTitle += ", ";
    //        }
    //        newTitle += channelName;

    //        first = false;
    //    }

    //    if (newTitle.isEmpty()) {
    //        newTitle = "empty";
    //    }

    //    this->tab->setTitle(newTitle);
}

}  // namespace widgets
}  // namespace chatterino