/*
    SPDX-FileCopyrightText: 2019 David Edmundson <davidedmundson@kde.org>
    SPDX-FileCopyrightText: 2019 Tranter Madi <trmdi@yandex.com>

    SPDX-License-Identifier: LGPL-2.0-or-later
*/

#include "strutmanager.h"
#include "screenpool.h"
#include "shellcorona.h"

#include <QDBusConnection>
#include <QDBusConnectionInterface>
#include <QDBusMetaType>
#include <QDBusServiceWatcher>

using namespace Qt::StringLiterals;

StrutManager::StrutManager(ShellCorona *plasmashellCorona)
    : QObject(plasmashellCorona)
    , m_plasmashellCorona(plasmashellCorona)
    , m_serviceWatcher(new QDBusServiceWatcher(this))
{
    qDBusRegisterMetaType<QList<QRect>>();

    QDBusConnection dbus = QDBusConnection::sessionBus();
    dbus.registerObject(u"/StrutManager"_s, this, QDBusConnection::ExportAllSlots);
    m_serviceWatcher->setConnection(dbus);

    connect(m_serviceWatcher, &QDBusServiceWatcher::serviceUnregistered, [this](const QString &service) {
        m_availableScreenRects.remove(service);
        m_availableScreenRegions.remove(service);
        m_serviceWatcher->removeWatchedService(service);

        for (int i = 0; i < m_plasmashellCorona->numScreens(); ++i) {
            Q_EMIT m_plasmashellCorona->availableScreenRectChanged(i);
        }
    });
}

QRect StrutManager::availableScreenRect(int id) const
{
    QRect r = m_plasmashellCorona->_availableScreenRect(id);
    for (const QHash<int, QRect> &service : std::as_const(m_availableScreenRects)) {
        if (!service.value(id).isNull()) {
            r &= service[id];
        }
    }
    return r;
}

QRect StrutManager::availableScreenRect(const QString &screenName) const
{
    return availableScreenRect(m_plasmashellCorona->screenPool()->idForName(screenName));
}

QRegion StrutManager::availableScreenRegion(int id) const
{
    QRegion r = m_plasmashellCorona->_availableScreenRegion(id);
    for (const QHash<int, QRegion> &service : std::as_const(m_availableScreenRegions)) {
        if (!service.value(id).isNull()) {
            r &= service[id];
        }
    }
    return r;
}

void StrutManager::setAvailableScreenRect(const QString &service, const QString &screenName, const QRect &rect)
{
    int id = m_plasmashellCorona->screenPool()->idForName(screenName);
    if (id == -1 || m_availableScreenRects.value(service).value(id) == rect || !addWatchedService(service)) {
        return;
    }
    m_availableScreenRects[service][id] = rect;
    Q_EMIT m_plasmashellCorona->availableScreenRectChanged(id);
}

void StrutManager::setAvailableScreenRegion(const QString &service, const QString &screenName, const QList<QRect> &rects)
{
    int id = m_plasmashellCorona->screenPool()->idForName(screenName);
    QRegion region;
    for (const QRect &rect : rects) {
        region += rect;
    }

    if (id == -1 || m_availableScreenRegions.value(service).value(id) == region || !addWatchedService(service)) {
        return;
    }
    m_availableScreenRegions[service][id] = region;
    Q_EMIT m_plasmashellCorona->availableScreenRegionChanged(id);
}

bool StrutManager::addWatchedService(const QString &service)
{
    if (!m_serviceWatcher->watchedServices().contains(service)) {
        if (!QDBusConnection::sessionBus().interface()->isServiceRegistered(service)) {
            return false;
        }
        m_serviceWatcher->addWatchedService(service);
    }
    return true;
}