#include "FakeEngine.h"
#include "input/KeyboardController.h"
#include "layout/LayoutModel.h"
#include "TestLayouts.h"

#include <QTest>
#include <xkbcommon/xkbcommon-keysyms.h>

using namespace Qt::StringLiterals;

namespace {

KeyDef makeKey(KeyType type, const QString &label = {})
{
    KeyDef k;
    k.type = type;
    k.label = label;
    return k;
}

} // namespace

class TestController : public QObject
{
    Q_OBJECT

private:
    FakeEngine engine;
    LayoutModel model;
    std::unique_ptr<KeyboardController> controller;
    qint64 now = 0;

    void tap(const KeyDef &key, KeyOutput output = KeyOutput::Primary, const QString &alternate = {})
    {
        now += 1000; // far apart: never a double tap
        controller->keyDown(key, now);
        controller->keyUp(key, output, alternate, now + 50);
    }

private Q_SLOTS:
    void init()
    {
        engine = {};
        model.setLayout(TestLayouts::build("us"));
        controller = std::make_unique<KeyboardController>(engine, model);
    }

    void typesLowercase()
    {
        tap(makeKey(KeyType::Character, u"a"_s));
        QCOMPARE(engine.output, u"a");
    }

    void shiftCapitalizesOneCharacter()
    {
        const KeyDef a = makeKey(KeyType::Character, u"a"_s);
        tap(makeKey(KeyType::Shift));
        QCOMPARE(controller->shiftMode(), KeyboardController::ShiftMode::Once);
        tap(a);
        tap(a);
        QCOMPARE(engine.output, u"Aa");
        QCOMPARE(controller->shiftMode(), KeyboardController::ShiftMode::Off);
    }

    void flickAndAlternateOutputs()
    {
        KeyDef e = makeKey(KeyType::Character, u"e"_s);
        e.flick = u"3"_s;
        tap(e, KeyOutput::Flick);
        tap(e, KeyOutput::Alternate, u"é"_s);
        QCOMPARE(engine.output, u"3é");
    }

    void backspaceActsOnPress()
    {
        controller->keyDown(makeKey(KeyType::Backspace), 0);
        QCOMPARE(engine.keysyms, QList<quint32>{XKB_KEY_BackSpace});
    }

    void enterSendsReturn()
    {
        tap(makeKey(KeyType::Enter));
        QCOMPARE(engine.keysyms, QList<quint32>{XKB_KEY_Return});
    }

    void layerSwitchChangesModelLayer()
    {
        KeyDef layer = makeKey(KeyType::LayerSwitch);
        layer.target = u"numbers"_s;
        controller->keyDown(layer, 0);
        QCOMPARE(model.layerName(), u"numbers");
    }

    void backspaceStopsOnRelease()
    {
        const KeyDef backspace = makeKey(KeyType::Backspace);
        controller->keyDown(backspace, 0);
        controller->keyUp(backspace, KeyOutput::Primary, {}, 50);
        QTest::qWait(700); // past the repeat delay
        QCOMPARE(engine.keysyms.size(), 1);
    }

    void capitalizesAtSentenceStart()
    {
        controller->resetContext();
        QCOMPARE(controller->shiftMode(), KeyboardController::ShiftMode::Once);
        for (const char *c : {"h", "i", ".", " "})
            tap(makeKey(KeyType::Character, QString::fromLatin1(c)));
        QCOMPARE(controller->shiftMode(), KeyboardController::ShiftMode::Once);
        tap(makeKey(KeyType::Character, u"o"_s));
        QCOMPARE(engine.output, u"Hi. O");
    }

    void noCapitalizationInPasswordFields()
    {
        TextContext context;
        context.purpose = TextContext::Purpose::Password;
        controller->setContext(context);
        QCOMPARE(controller->shiftMode(), KeyboardController::ShiftMode::Off);
    }

    void fieldTextDrivesCapitalization()
    {
        TextContext context;
        context.hasSurroundingText = true;
        context.textBeforeCursor = u"Done! "_s;
        controller->setContext(context);
        QCOMPARE(controller->shiftMode(), KeyboardController::ShiftMode::Once);
        context.textBeforeCursor = u"Done, "_s;
        controller->setContext(context);
        QCOMPARE(controller->shiftMode(), KeyboardController::ShiftMode::Off);
    }

    void doubleSpaceTypesPeriod()
    {
        const KeyDef space = makeKey(KeyType::Space);
        tap(makeKey(KeyType::Character, u"a"_s));
        tap(space);
        tap(space);
        QCOMPARE(engine.output, u"a. ");
        QCOMPARE(engine.mismatchedReplacements, 0);
        // A Backspace keysym may reach the client after the commit and eat the new space.
        QVERIFY(engine.keysyms.isEmpty());
        QCOMPARE(controller->shiftMode(), KeyboardController::ShiftMode::Once);
    }

    void doubleSpacePeriodCanBeTurnedOff()
    {
        controller->setOptions({.doubleSpacePeriod = false});
        const KeyDef space = makeKey(KeyType::Space);
        tap(makeKey(KeyType::Character, u"a"_s));
        tap(space);
        tap(space);
        QCOMPARE(engine.output, u"A  ");
    }

    void autoCapitalizationCanBeTurnedOff()
    {
        controller->resetContext();
        controller->setOptions({.autoCapitalize = false});
        QCOMPARE(controller->shiftMode(), KeyboardController::ShiftMode::Off);
        tap(makeKey(KeyType::Character, u"a"_s));
        QCOMPARE(engine.output, u"a");
    }

    void doubleTapShiftLocksAtSentenceStart()
    {
        controller->resetContext(); // a field was focused
        QCOMPARE(controller->shiftMode(), KeyboardController::ShiftMode::Once); // auto-shift
        const KeyDef shift = makeKey(KeyType::Shift);
        controller->keyDown(shift, 5000);
        controller->keyUp(shift, KeyOutput::Primary, {}, 5050);
        controller->keyDown(shift, 5200);
        controller->keyUp(shift, KeyOutput::Primary, {}, 5250);
        QCOMPARE(controller->shiftMode(), KeyboardController::ShiftMode::Locked);
    }

    void slideTypesSymbolAndSwitchesBack()
    {
        KeyDef layer = makeKey(KeyType::LayerSwitch);
        layer.target = u"numbers"_s;
        controller->keyDown(layer, 0);
        controller->slideReleased(makeKey(KeyType::Character, u"5"_s), 100);
        QCOMPARE(engine.output, u"5");
        QCOMPARE(model.layerName(), u"letters");
    }

    void trackpadMovesCursor()
    {
        controller->moveCursor({2, -1});
        QCOMPARE(engine.keysyms, (QList<quint32>{XKB_KEY_Right, XKB_KEY_Right, XKB_KEY_Up}));
    }

    void globeRequestsNextLayout()
    {
        int requested = 0;
        connect(controller.get(), &KeyboardController::nextLayoutRequested, this, [&] { ++requested; });
        tap(makeKey(KeyType::Globe));
        QCOMPARE(requested, 1);
    }

    void dismissEmitsSignal()
    {
        int dismissed = 0;
        connect(controller.get(), &KeyboardController::dismissRequested, this, [&] { ++dismissed; });
        tap(makeKey(KeyType::Dismiss));
        QCOMPARE(dismissed, 1);
    }
};

QTEST_GUILESS_MAIN(TestController)
#include "tst_controller.moc"