/*
    KWin - the KDE window manager
    This file is part of the KDE project.

    SPDX-FileCopyrightText: 2019 David Edmundson <davidedmundson@kde.org>
    SPDX-FileCopyrightText: 2019 Vlad Zahorodnii <vlad.zahorodnii@kde.org>
    SPDX-FileCopyrightText: 2023 Natalie Clarius <natalie_clarius@yahoo.de>

    SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "kwin_wayland_test.h"

#include "core/output.h"
#include "core/outputbackend.h"
#include "placement.h"
#include "pointer_input.h"
#include "wayland_server.h"
#include "window.h"
#include "workspace.h"

#include <KWayland/Client/compositor.h>
#include <KWayland/Client/plasmashell.h>
#include <KWayland/Client/shm_pool.h>
#include <KWayland/Client/surface.h>

using namespace KWin;

static const QString s_socketName = QStringLiteral("wayland_test_kwin_placement-0");

struct PlaceWindowResult
{
    QSizeF initiallyConfiguredSize;
    Test::XdgToplevel::States initiallyConfiguredStates;
    QRectF finalGeometry;
};

class TestPlacement : public QObject
{
    Q_OBJECT

private Q_SLOTS:
    void init();
    void cleanup();
    void initTestCase();

    void testPlaceSmart();
    void testPlaceMaximized();
    void testPlaceMaximizedLeavesFullscreen();
    void testPlaceCentered();
    void testPlaceUnderMouse();
    void testPlaceZeroCornered();
    void testPlaceRandom();
    void testFullscreen();
    void testCascadeIfCovering();
    void testCascadeIfCoveringIgnoreNonCovering();
    void testCascadeIfCoveringIgnoreOutOfArea();
    void testCascadeIfCoveringIgnoreAlreadyCovered();

private:
    void setPlacementPolicy(PlacementPolicy policy);
    /*
     * Create a window and return relevant results for testing
     * defaultSize is the buffer size to use if the compositor returns an empty size in the first configure
     * event.
     */
    std::pair<PlaceWindowResult, std::unique_ptr<KWayland::Client::Surface>> createAndPlaceWindow(const QSize &defaultSize);
};

void TestPlacement::init()
{
    QVERIFY(Test::setupWaylandConnection(Test::AdditionalWaylandInterface::PlasmaShell));

    workspace()->setActiveOutput(QPoint(640, 512));
    KWin::input()->pointer()->warp(QPoint(640, 512));
}

void TestPlacement::cleanup()
{
    Test::destroyWaylandConnection();
}

void TestPlacement::initTestCase()
{
    qRegisterMetaType<KWin::Window *>();
    QSignalSpy applicationStartedSpy(kwinApp(), &Application::started);
    QVERIFY(waylandServer()->init(s_socketName));
    QMetaObject::invokeMethod(kwinApp()->outputBackend(), "setVirtualOutputs", Qt::DirectConnection, Q_ARG(QVector<QRect>, QVector<QRect>() << QRect(0, 0, 1280, 1024) << QRect(1280, 0, 1280, 1024)));

    kwinApp()->setConfig(KSharedConfig::openConfig(QString(), KConfig::SimpleConfig));

    kwinApp()->start();
    QVERIFY(applicationStartedSpy.wait());
    const auto outputs = workspace()->outputs();
    QCOMPARE(outputs.count(), 2);
    QCOMPARE(outputs[0]->geometry(), QRect(0, 0, 1280, 1024));
    QCOMPARE(outputs[1]->geometry(), QRect(1280, 0, 1280, 1024));
}

void TestPlacement::setPlacementPolicy(PlacementPolicy policy)
{
    auto group = kwinApp()->config()->group("Windows");
    group.writeEntry("Placement", Placement::policyToString(policy));
    group.sync();
    Workspace::self()->slotReconfigure();
}

std::pair<PlaceWindowResult, std::unique_ptr<KWayland::Client::Surface>> TestPlacement::createAndPlaceWindow(const QSize &defaultSize)
{
    PlaceWindowResult rc;

    // create a new window
    std::unique_ptr<KWayland::Client::Surface> surface = Test::createSurface();
    auto shellSurface = Test::createXdgToplevelSurface(surface.get(), Test::CreationSetup::CreateOnly, surface.get());

    QSignalSpy toplevelConfigureRequestedSpy(shellSurface, &Test::XdgToplevel::configureRequested);
    QSignalSpy surfaceConfigureRequestedSpy(shellSurface->xdgSurface(), &Test::XdgSurface::configureRequested);
    surface->commit(KWayland::Client::Surface::CommitFlag::None);
    surfaceConfigureRequestedSpy.wait();

    rc.initiallyConfiguredSize = toplevelConfigureRequestedSpy[0][0].toSize();
    rc.initiallyConfiguredStates = toplevelConfigureRequestedSpy[0][1].value<Test::XdgToplevel::States>();
    shellSurface->xdgSurface()->ack_configure(surfaceConfigureRequestedSpy[0][0].toUInt());

    QSizeF size = rc.initiallyConfiguredSize;

    if (size.isEmpty()) {
        size = defaultSize;
    }

    auto window = Test::renderAndWaitForShown(surface.get(), size.toSize(), Qt::red);

    rc.finalGeometry = window->frameGeometry();
    return {rc, std::move(surface)};
}

void TestPlacement::testPlaceSmart()
{
    setPlacementPolicy(PlacementSmart);

    std::vector<std::unique_ptr<KWayland::Client::Surface>> surfaces;
    QRegion usedArea;

    for (int i = 0; i < 4; i++) {
        auto [windowPlacement, surface] = createAndPlaceWindow(QSize(600, 500));
        // smart placement shouldn't define a size on windows
        QCOMPARE(windowPlacement.initiallyConfiguredSize, QSize(0, 0));
        QCOMPARE(windowPlacement.finalGeometry.size(), QSize(600, 500));

        // exact placement isn't a defined concept that should be tested
        // but the goal of smart placement is to make sure windows don't overlap until they need to
        // 4 windows of 600, 500 should fit without overlap
        QVERIFY(!usedArea.intersects(windowPlacement.finalGeometry.toRect()));
        usedArea += windowPlacement.finalGeometry.toRect();
        surfaces.push_back(std::move(surface));
    }
}

void TestPlacement::testPlaceMaximized()
{
    setPlacementPolicy(PlacementMaximizing);

    // add a top panel
    std::unique_ptr<KWayland::Client::Surface> panelSurface(Test::createSurface());
    std::unique_ptr<QObject> panelShellSurface(Test::createXdgToplevelSurface(panelSurface.get()));
    std::unique_ptr<KWayland::Client::PlasmaShellSurface> plasmaSurface(Test::waylandPlasmaShell()->createSurface(panelSurface.get()));
    plasmaSurface->setRole(KWayland::Client::PlasmaShellSurface::Role::Panel);
    plasmaSurface->setPosition(QPoint(0, 0));
    Test::renderAndWaitForShown(panelSurface.get(), QSize(1280, 20), Qt::blue);

    std::vector<std::unique_ptr<KWayland::Client::Surface>> surfaces;

    // all windows should be initially maximized with an initial configure size sent
    for (int i = 0; i < 4; i++) {
        auto [windowPlacement, surface] = createAndPlaceWindow(QSize(600, 500));
        QVERIFY(windowPlacement.initiallyConfiguredStates & Test::XdgToplevel::State::Maximized);
        QCOMPARE(windowPlacement.initiallyConfiguredSize, QSize(1280, 1024 - 20));
        QCOMPARE(windowPlacement.finalGeometry, QRect(0, 20, 1280, 1024 - 20)); // under the panel
        surfaces.push_back(std::move(surface));
    }
}

void TestPlacement::testPlaceMaximizedLeavesFullscreen()
{
    setPlacementPolicy(PlacementMaximizing);

    // add a top panel
    std::unique_ptr<KWayland::Client::Surface> panelSurface(Test::createSurface());
    std::unique_ptr<QObject> panelShellSurface(Test::createXdgToplevelSurface(panelSurface.get()));
    std::unique_ptr<KWayland::Client::PlasmaShellSurface> plasmaSurface(Test::waylandPlasmaShell()->createSurface(panelSurface.get()));
    plasmaSurface->setRole(KWayland::Client::PlasmaShellSurface::Role::Panel);
    plasmaSurface->setPosition(QPoint(0, 0));
    Test::renderAndWaitForShown(panelSurface.get(), QSize(1280, 20), Qt::blue);

    std::vector<std::unique_ptr<KWayland::Client::Surface>> surfaces;

    // all windows should be initially fullscreen with an initial configure size sent, despite the policy
    for (int i = 0; i < 4; i++) {
        std::unique_ptr<KWayland::Client::Surface> surface = Test::createSurface();
        auto shellSurface = Test::createXdgToplevelSurface(surface.get(), Test::CreationSetup::CreateOnly, surface.get());
        shellSurface->set_fullscreen(nullptr);
        QSignalSpy toplevelConfigureRequestedSpy(shellSurface, &Test::XdgToplevel::configureRequested);
        QSignalSpy surfaceConfigureRequestedSpy(shellSurface->xdgSurface(), &Test::XdgSurface::configureRequested);
        surface->commit(KWayland::Client::Surface::CommitFlag::None);
        QVERIFY(surfaceConfigureRequestedSpy.wait());

        auto initiallyConfiguredSize = toplevelConfigureRequestedSpy[0][0].toSize();
        auto initiallyConfiguredStates = toplevelConfigureRequestedSpy[0][1].value<Test::XdgToplevel::States>();
        shellSurface->xdgSurface()->ack_configure(surfaceConfigureRequestedSpy[0][0].toUInt());

        auto window = Test::renderAndWaitForShown(surface.get(), initiallyConfiguredSize, Qt::red);

        QVERIFY(initiallyConfiguredStates & Test::XdgToplevel::State::Fullscreen);
        QCOMPARE(initiallyConfiguredSize, QSize(1280, 1024));
        QCOMPARE(window->frameGeometry(), QRect(0, 0, 1280, 1024));

        surfaces.push_back(std::move(surface));
    }
}

void TestPlacement::testPlaceCentered()
{
    // This test verifies that Centered placement policy works.

    KConfigGroup group = kwinApp()->config()->group("Windows");
    group.writeEntry("Placement", Placement::policyToString(PlacementCentered));
    group.sync();
    workspace()->slotReconfigure();

    std::unique_ptr<KWayland::Client::Surface> surface(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface(Test::createXdgToplevelSurface(surface.get()));
    Window *window = Test::renderAndWaitForShown(surface.get(), QSize(100, 50), Qt::red);
    QVERIFY(window);
    QCOMPARE(window->frameGeometry(), QRect(590, 487, 100, 50));

    shellSurface.reset();
    QVERIFY(Test::waitForWindowClosed(window));
}

void TestPlacement::testPlaceUnderMouse()
{
    // This test verifies that Under Mouse placement policy works.

    KConfigGroup group = kwinApp()->config()->group("Windows");
    group.writeEntry("Placement", Placement::policyToString(PlacementUnderMouse));
    group.sync();
    workspace()->slotReconfigure();

    KWin::input()->pointer()->warp(QPoint(200, 300));
    QCOMPARE(KWin::Cursors::self()->mouse()->pos(), QPoint(200, 300));

    std::unique_ptr<KWayland::Client::Surface> surface(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface(Test::createXdgToplevelSurface(surface.get()));
    Window *window = Test::renderAndWaitForShown(surface.get(), QSize(100, 50), Qt::red);
    QVERIFY(window);
    QCOMPARE(window->frameGeometry(), QRect(150, 275, 100, 50));

    shellSurface.reset();
    QVERIFY(Test::waitForWindowClosed(window));
}

void TestPlacement::testPlaceZeroCornered()
{
    // This test verifies that the Zero-Cornered placement policy works.

    KConfigGroup group = kwinApp()->config()->group("Windows");
    group.writeEntry("Placement", Placement::policyToString(PlacementZeroCornered));
    group.sync();
    workspace()->slotReconfigure();

    std::unique_ptr<KWayland::Client::Surface> surface1(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface1(Test::createXdgToplevelSurface(surface1.get()));
    Window *window1 = Test::renderAndWaitForShown(surface1.get(), QSize(100, 50), Qt::red);
    QVERIFY(window1);
    QCOMPARE(window1->pos(), QPoint(0, 0));
    QCOMPARE(window1->size(), QSize(100, 50));

    std::unique_ptr<KWayland::Client::Surface> surface2(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface2(Test::createXdgToplevelSurface(surface2.get()));
    Window *window2 = Test::renderAndWaitForShown(surface2.get(), QSize(100, 50), Qt::blue);
    QVERIFY(window2);
    QCOMPARE(window2->pos(), window1->pos() + workspace()->cascadeOffset(window2));
    QCOMPARE(window2->size(), QSize(100, 50));

    std::unique_ptr<KWayland::Client::Surface> surface3(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface3(Test::createXdgToplevelSurface(surface3.get()));
    Window *window3 = Test::renderAndWaitForShown(surface3.get(), QSize(100, 50), Qt::green);
    QVERIFY(window3);
    QCOMPARE(window3->pos(), window2->pos() + workspace()->cascadeOffset(window3));
    QCOMPARE(window3->size(), QSize(100, 50));

    shellSurface3.reset();
    QVERIFY(Test::waitForWindowClosed(window3));
    shellSurface2.reset();
    QVERIFY(Test::waitForWindowClosed(window2));
    shellSurface1.reset();
    QVERIFY(Test::waitForWindowClosed(window1));
}

void TestPlacement::testPlaceRandom()
{
    // This test verifies that Random placement policy works.

    KConfigGroup group = kwinApp()->config()->group("Windows");
    group.writeEntry("Placement", Placement::policyToString(PlacementRandom));
    group.sync();
    workspace()->slotReconfigure();

    std::unique_ptr<KWayland::Client::Surface> surface1(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface1(Test::createXdgToplevelSurface(surface1.get()));
    Window *window1 = Test::renderAndWaitForShown(surface1.get(), QSize(100, 50), Qt::red);
    QVERIFY(window1);
    QCOMPARE(window1->size(), QSize(100, 50));

    std::unique_ptr<KWayland::Client::Surface> surface2(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface2(Test::createXdgToplevelSurface(surface2.get()));
    Window *window2 = Test::renderAndWaitForShown(surface2.get(), QSize(100, 50), Qt::blue);
    QVERIFY(window2);
    QVERIFY(window2->pos() != window1->pos());
    QCOMPARE(window2->size(), QSize(100, 50));

    std::unique_ptr<KWayland::Client::Surface> surface3(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface3(Test::createXdgToplevelSurface(surface3.get()));
    Window *window3 = Test::renderAndWaitForShown(surface3.get(), QSize(100, 50), Qt::green);
    QVERIFY(window3);
    QVERIFY(window3->pos() != window1->pos());
    QVERIFY(window3->pos() != window2->pos());
    QCOMPARE(window3->size(), QSize(100, 50));

    shellSurface3.reset();
    QVERIFY(Test::waitForWindowClosed(window3));
    shellSurface2.reset();
    QVERIFY(Test::waitForWindowClosed(window2));
    shellSurface1.reset();
    QVERIFY(Test::waitForWindowClosed(window1));
}

void TestPlacement::testFullscreen()
{
    const QList<Output *> outputs = workspace()->outputs();

    setPlacementPolicy(PlacementSmart);
    std::unique_ptr<KWayland::Client::Surface> surface(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface(Test::createXdgToplevelSurface(surface.get()));

    Window *window = Test::renderAndWaitForShown(surface.get(), QSize(100, 50), Qt::red);
    QVERIFY(window);
    window->sendToOutput(outputs[0]);

    // Wait for the configure event with the activated state.
    QSignalSpy toplevelConfigureRequestedSpy(shellSurface.get(), &Test::XdgToplevel::configureRequested);
    QSignalSpy surfaceConfigureRequestedSpy(shellSurface->xdgSurface(), &Test::XdgSurface::configureRequested);
    QVERIFY(surfaceConfigureRequestedSpy.wait());

    window->setFullScreen(true);

    QSignalSpy geometryChangedSpy(window, &Window::frameGeometryChanged);
    QVERIFY(surfaceConfigureRequestedSpy.wait());
    shellSurface->xdgSurface()->ack_configure(surfaceConfigureRequestedSpy.last().at(0).value<quint32>());
    Test::render(surface.get(), toplevelConfigureRequestedSpy.last().at(0).toSize(), Qt::red);
    QVERIFY(geometryChangedSpy.wait());
    QCOMPARE(window->frameGeometry(), outputs[0]->geometry());

    // this doesn't require a round trip, so should be immediate
    window->sendToOutput(outputs[1]);
    QCOMPARE(window->frameGeometry(), outputs[1]->geometry());
    QCOMPARE(geometryChangedSpy.count(), 2);
}

void TestPlacement::testCascadeIfCovering()
{
    // This test verifies that the cascade-if-covering adjustment works for the Centered placement
    // policy.

    KConfigGroup group = kwinApp()->config()->group("Windows");
    group.writeEntry("Placement", Placement::policyToString(PlacementCentered));
    group.sync();
    workspace()->slotReconfigure();

    // window should be in center
    std::unique_ptr<KWayland::Client::Surface> surface1(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface1(Test::createXdgToplevelSurface(surface1.get()));
    Window *window1 = Test::renderAndWaitForShown(surface1.get(), QSize(100, 50), Qt::red);
    QVERIFY(window1);
    QCOMPARE(window1->pos(), QPoint(590, 487));
    QCOMPARE(window1->size(), QSize(100, 50));

    // window should be cascaded to avoid overlapping window 1
    std::unique_ptr<KWayland::Client::Surface> surface2(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface2(Test::createXdgToplevelSurface(surface2.get()));
    Window *window2 = Test::renderAndWaitForShown(surface2.get(), QSize(100, 50), Qt::blue);
    QVERIFY(window2);
    QCOMPARE(window2->pos(), window1->pos() + workspace()->cascadeOffset(window2));
    QCOMPARE(window2->size(), QSize(100, 50));

    // window should be cascaded to avoid overlapping window 1 and 2
    std::unique_ptr<KWayland::Client::Surface> surface3(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface3(Test::createXdgToplevelSurface(surface3.get()));
    Window *window3 = Test::renderAndWaitForShown(surface3.get(), QSize(100, 50), Qt::green);
    QVERIFY(window3);
    QCOMPARE(window3->pos(), window2->pos() + workspace()->cascadeOffset(window3));
    QCOMPARE(window3->size(), QSize(100, 50));

    shellSurface3.reset();
    QVERIFY(Test::waitForWindowClosed(window3));
    shellSurface2.reset();
    QVERIFY(Test::waitForWindowClosed(window2));
    shellSurface1.reset();
    QVERIFY(Test::waitForWindowClosed(window1));
}

void TestPlacement::testCascadeIfCoveringIgnoreNonCovering()
{
    // This test verifies that the cascade-if-covering adjustment doesn't take effect when the
    // other window wouldn't be fully covered.

    KConfigGroup group = kwinApp()->config()->group("Windows");
    group.writeEntry("Placement", Placement::policyToString(PlacementCentered));
    group.sync();
    workspace()->slotReconfigure();

    std::unique_ptr<KWayland::Client::Surface> surface1(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface1(Test::createXdgToplevelSurface(surface1.get()));
    Window *window1 = Test::renderAndWaitForShown(surface1.get(), QSize(100, 50), Qt::red);
    QVERIFY(window1);

    // window should not be cascaded since it wouldn't fully overlap
    std::unique_ptr<KWayland::Client::Surface> surface2(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface2(Test::createXdgToplevelSurface(surface2.get()));
    Window *window2 = Test::renderAndWaitForShown(surface2.get(), QSize(50, 50), Qt::blue);
    QVERIFY(window2);
    QCOMPARE(window2->pos(), QPoint(615, 487));
    QCOMPARE(window2->size(), QSize(50, 50));

    shellSurface2.reset();
    QVERIFY(Test::waitForWindowClosed(window2));
    shellSurface1.reset();
    QVERIFY(Test::waitForWindowClosed(window1));
}

void TestPlacement::testCascadeIfCoveringIgnoreOutOfArea()
{
    // This test verifies that the cascade-if-covering adjustment doesn't take effect when there is
    // not enough space on the placement area to cascade.

    KConfigGroup group = kwinApp()->config()->group("Windows");
    group.writeEntry("Placement", Placement::policyToString(PlacementCentered));
    group.sync();
    workspace()->slotReconfigure();

    std::unique_ptr<KWayland::Client::Surface> surface1(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface1(Test::createXdgToplevelSurface(surface1.get()));
    Window *window1 = Test::renderAndWaitForShown(surface1.get(), QSize(100, 50), Qt::red);
    QVERIFY(window1);

    // window should not be cascaded since it would be out of bounds of work area
    std::unique_ptr<KWayland::Client::Surface> surface2(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface2(Test::createXdgToplevelSurface(surface2.get()));
    Window *window2 = Test::renderAndWaitForShown(surface2.get(), QSize(1280, 1024), Qt::blue);
    QVERIFY(window2);
    QCOMPARE(window2->pos(), QPoint(0, 0));
    QCOMPARE(window2->size(), QSize(1280, 1024));

    shellSurface2.reset();
    QVERIFY(Test::waitForWindowClosed(window2));
    shellSurface1.reset();
    QVERIFY(Test::waitForWindowClosed(window1));
}

void TestPlacement::testCascadeIfCoveringIgnoreAlreadyCovered()
{
    // This test verifies that the cascade-if-covering adjustment doesn't take effect when the
    // other window is already fully covered by other windows anyway.

    KConfigGroup group = kwinApp()->config()->group("Windows");
    group.writeEntry("Placement", Placement::policyToString(PlacementCentered));
    group.sync();
    workspace()->slotReconfigure();

    std::unique_ptr<KWayland::Client::Surface> surface1(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface1(Test::createXdgToplevelSurface(surface1.get()));
    Window *window1 = Test::renderAndWaitForShown(surface1.get(), QSize(100, 50), Qt::red);
    QVERIFY(window1);

    std::unique_ptr<KWayland::Client::Surface> surface2(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface2(Test::createXdgToplevelSurface(surface2.get()));
    Window *window2 = Test::renderAndWaitForShown(surface2.get(), QSize(1280, 1024), Qt::blue);
    QVERIFY(window2);

    // window should not be cascaded since the small window is already fully covered by the
    // large window anyway
    std::unique_ptr<KWayland::Client::Surface> surface3(Test::createSurface());
    std::unique_ptr<Test::XdgToplevel> shellSurface3(Test::createXdgToplevelSurface(surface3.get()));
    Window *window3 = Test::renderAndWaitForShown(surface3.get(), QSize(100, 50), Qt::green);
    QVERIFY(window3);
    QCOMPARE(window3->pos(), QPoint(590, 487));
    QCOMPARE(window3->size(), QSize(100, 50));

    shellSurface3.reset();
    QVERIFY(Test::waitForWindowClosed(window3));
    shellSurface2.reset();
    QVERIFY(Test::waitForWindowClosed(window2));
    shellSurface1.reset();
    QVERIFY(Test::waitForWindowClosed(window1));
}

WAYLANDTEST_MAIN(TestPlacement)
#include "placement_test.moc"