// SPDX-FileCopyrightText: 2021 Nheko Contributors
//
// SPDX-License-Identifier: GPL-3.0-or-later

#include "CommunitiesModel.h"

#include <set>

#include "Cache.h"
#include "UserSettingsPage.h"

CommunitiesModel::CommunitiesModel(QObject *parent)
  : QAbstractListModel(parent)
{}

QHash<int, QByteArray>
CommunitiesModel::roleNames() const
{
    return {
      {AvatarUrl, "avatarUrl"},
      {DisplayName, "displayName"},
      {Tooltip, "tooltip"},
      {ChildrenHidden, "childrenHidden"},
      {Hidden, "hidden"},
      {Id, "id"},
    };
}

QVariant
CommunitiesModel::data(const QModelIndex &index, int role) const
{
    if (index.row() == 0) {
        switch (role) {
        case CommunitiesModel::Roles::AvatarUrl:
            return QString(":/icons/icons/ui/world.svg");
        case CommunitiesModel::Roles::DisplayName:
            return tr("All rooms");
        case CommunitiesModel::Roles::Tooltip:
            return tr("Shows all rooms without filtering.");
        case CommunitiesModel::Roles::ChildrenHidden:
            return false;
        case CommunitiesModel::Roles::Hidden:
            return false;
        case CommunitiesModel::Roles::Id:
            return "";
        }
    } else if (index.row() - 1 < spaceOrder_.size()) {
        auto id = spaceOrder_.at(index.row() - 1);
        switch (role) {
        case CommunitiesModel::Roles::AvatarUrl:
            return QString::fromStdString(spaces_.at(id).avatar_url);
        case CommunitiesModel::Roles::DisplayName:
        case CommunitiesModel::Roles::Tooltip:
            return QString::fromStdString(spaces_.at(id).name);
        case CommunitiesModel::Roles::ChildrenHidden:
            return true;
        case CommunitiesModel::Roles::Hidden:
            return hiddentTagIds_.contains("space:" + id);
        case CommunitiesModel::Roles::Id:
            return "space:" + id;
        }
    } else if (index.row() - 1 < tags_.size() + spaceOrder_.size()) {
        auto tag = tags_.at(index.row() - 1 - spaceOrder_.size());
        if (tag == "m.favourite") {
            switch (role) {
            case CommunitiesModel::Roles::AvatarUrl:
                return QString(":/icons/icons/ui/star.svg");
            case CommunitiesModel::Roles::DisplayName:
                return tr("Favourites");
            case CommunitiesModel::Roles::Tooltip:
                return tr("Rooms you have favourited.");
            }
        } else if (tag == "m.lowpriority") {
            switch (role) {
            case CommunitiesModel::Roles::AvatarUrl:
                return QString(":/icons/icons/ui/lowprio.svg");
            case CommunitiesModel::Roles::DisplayName:
                return tr("Low Priority");
            case CommunitiesModel::Roles::Tooltip:
                return tr("Rooms with low priority.");
            }
        } else if (tag == "m.server_notice") {
            switch (role) {
            case CommunitiesModel::Roles::AvatarUrl:
                return QString(":/icons/icons/ui/tag.svg");
            case CommunitiesModel::Roles::DisplayName:
                return tr("Server Notices");
            case CommunitiesModel::Roles::Tooltip:
                return tr("Messages from your server or administrator.");
            }
        } else {
            switch (role) {
            case CommunitiesModel::Roles::AvatarUrl:
                return QString(":/icons/icons/ui/tag.svg");
            case CommunitiesModel::Roles::DisplayName:
            case CommunitiesModel::Roles::Tooltip:
                return tag.mid(2);
            }
        }

        switch (role) {
        case CommunitiesModel::Roles::Hidden:
            return hiddentTagIds_.contains("tag:" + tag);
        case CommunitiesModel::Roles::ChildrenHidden:
            return true;
        case CommunitiesModel::Roles::Id:
            return "tag:" + tag;
        }
    }
    return QVariant();
}

void
CommunitiesModel::initializeSidebar()
{
    beginResetModel();
    tags_.clear();
    spaceOrder_.clear();
    spaces_.clear();

    std::set<std::string> ts;
    std::vector<RoomInfo> tempSpaces;
    auto infos = cache::roomInfo();
    for (auto it = infos.begin(); it != infos.end(); it++) {
        if (it.value().is_space) {
            spaceOrder_.push_back(it.key());
            spaces_[it.key()] = it.value();
        } else {
            for (const auto &t : it.value().tags) {
                if (t.find("u.") == 0 || t.find("m." == 0)) {
                    ts.insert(t);
                }
            }
        }
    }

    for (const auto &t : ts)
        tags_.push_back(QString::fromStdString(t));

    hiddentTagIds_ = UserSettings::instance()->hiddenTags();
    endResetModel();

    emit tagsChanged();
    emit hiddenTagsChanged();
}

void
CommunitiesModel::clear()
{
    beginResetModel();
    tags_.clear();
    endResetModel();
    resetCurrentTagId();

    emit tagsChanged();
}

void
CommunitiesModel::sync(const mtx::responses::Rooms &rooms)
{
    bool tagsUpdated = false;

    for (const auto &[roomid, room] : rooms.join) {
        (void)roomid;
        for (const auto &e : room.account_data.events)
            if (std::holds_alternative<
                  mtx::events::AccountDataEvent<mtx::events::account_data::Tags>>(e)) {
                tagsUpdated = true;
            }
        for (const auto &e : room.state.events)
            if (std::holds_alternative<mtx::events::StateEvent<mtx::events::state::space::Child>>(
                  e) ||
                std::holds_alternative<mtx::events::StateEvent<mtx::events::state::space::Parent>>(
                  e)) {
                tagsUpdated = true;
            }
        for (const auto &e : room.timeline.events)
            if (std::holds_alternative<mtx::events::StateEvent<mtx::events::state::space::Child>>(
                  e) ||
                std::holds_alternative<mtx::events::StateEvent<mtx::events::state::space::Parent>>(
                  e)) {
                tagsUpdated = true;
            }
    }
    for (const auto &[roomid, room] : rooms.leave) {
        (void)room;
        if (spaceOrder_.contains(QString::fromStdString(roomid)))
            tagsUpdated = true;
    }

    if (tagsUpdated)
        initializeSidebar();
}

void
CommunitiesModel::setCurrentTagId(QString tagId)
{
    if (tagId.startsWith("tag:")) {
        auto tag = tagId.mid(4);
        for (const auto &t : tags_) {
            if (t == tag) {
                this->currentTagId_ = tagId;
                emit currentTagIdChanged(currentTagId_);
                return;
            }
        }
    } else if (tagId.startsWith("space:")) {
        auto tag = tagId.mid(6);
        for (const auto &t : spaceOrder_) {
            if (t == tag) {
                this->currentTagId_ = tagId;
                emit currentTagIdChanged(currentTagId_);
                return;
            }
        }
    }

    this->currentTagId_ = "";
    emit currentTagIdChanged(currentTagId_);
}

void
CommunitiesModel::toggleTagId(QString tagId)
{
    if (hiddentTagIds_.contains(tagId)) {
        hiddentTagIds_.removeOne(tagId);
        UserSettings::instance()->setHiddenTags(hiddentTagIds_);
    } else {
        hiddentTagIds_.push_back(tagId);
        UserSettings::instance()->setHiddenTags(hiddentTagIds_);
    }

    if (tagId.startsWith("tag:")) {
        auto idx = tags_.indexOf(tagId.mid(4));
        if (idx != -1)
            emit dataChanged(
              index(idx + 1 + spaceOrder_.size()), index(idx + 1 + spaceOrder_.size()), {Hidden});
    } else if (tagId.startsWith("space:")) {
        auto idx = spaceOrder_.indexOf(tagId.mid(6));
        if (idx != -1)
            emit dataChanged(index(idx + 1), index(idx + 1), {Hidden});
    }

    emit hiddenTagsChanged();
}