/**
 * @RDE_HEADER@
 * Unit Tests for Rubberbands Module - Qt6 Migration
 * $Id$
 * $HeadURL$
 * $Author$
 */

#include <gtest/gtest.h>
#include <QCoreApplication>
#include <QPointF>
#include <QPolygonF>
#include <QTouchEvent>
#include <QEventPoint>
#include <QFuture>
#include <QtConcurrent>
#include <chrono>
#include <thread>

namespace
{
    // Mock class to simulate rubberband behavior for testing
    class MockRubberband
    {
    public:
        MockRubberband() : m_active(false) {}
        
        void setActive(bool active) { m_active = active; }
        bool isActive() const { return m_active; }
        
        void addPoint(const QPointF& point) { m_points.append(point); }
        int pointCount() const { return m_points.size(); }
        
        void clear() { m_points.clear(); }
        
    private:
        bool m_active;
        QList<QPointF> m_points;
    };
}

// Test Rubberbands QTouchEvent API (Qt6)
TEST(RubberbandsTest, QTouchEvent_API_Qt6)
{
    // Qt6 changes:
    // - touchPoints() -> points()
    // - QEventPoint::screenPos() -> globalPosition()
    
    // Verify QEventPoint API exists and works
    // Note: QTouchEvent cannot be directly constructed in tests, 
    // but we can verify the point types
    
    // Test that QEventPoint has the expected Qt6 methods
    // This is a compile-time check that the API exists
    using PointType = QEventPoint;
    
    // Verify the types we use in Rubberbands code
    static_assert(std::is_same_v<decltype(&QEventPoint::position), QPointF(QEventPoint::*)() const>);
    static_assert(std::is_same_v<decltype(&QEventPoint::globalPosition), QPointF(QEventPoint::*)() const>);
    
    SUCCEED() << "QEventPoint Qt6 API verified";
}

// Test Rubberbands QFuture continuation pattern
TEST(RubberbandsTest, QFuture_Continuation_Pattern)
{
    // Qt6: QFuture supports .then() continuations
    // This pattern is used in Rubberbands for async operations
    
    QFuture<int> future = QtConcurrent::run([]() {
        std::this_thread::sleep_for(std::chrono::milliseconds(10));
        return 42;
    });
    
    bool continuationCalled = false;
    int result = 0;
    
    QFuture<void> continued = future.then([&continuationCalled, &result](QFuture<int> f) {
        continuationCalled = true;
        result = f.result();
    });
    
    continued.waitForFinished();
    
    EXPECT_TRUE(continuationCalled);
    EXPECT_EQ(result, 42);
}

// Test Rubberbands point collection
TEST(RubberbandsTest, Point_Collection)
{
    MockRubberband rubberband;
    
    EXPECT_FALSE(rubberband.isActive());
    EXPECT_EQ(rubberband.pointCount(), 0);
    
    rubberband.setActive(true);
    EXPECT_TRUE(rubberband.isActive());
    
    rubberband.addPoint(QPointF(10.0, 20.0));
    rubberband.addPoint(QPointF(30.0, 40.0));
    rubberband.addPoint(QPointF(50.0, 60.0));
    
    EXPECT_EQ(rubberband.pointCount(), 3);
    
    rubberband.clear();
    EXPECT_EQ(rubberband.pointCount(), 0);
}

// Test Rubberbands polygon operations
TEST(RubberbandsTest, Polygon_Operations)
{
    QPolygonF polygon;
    
    // Add points
    polygon << QPointF(0, 0) << QPointF(100, 0) 
            << QPointF(100, 100) << QPointF(0, 100);
    
    EXPECT_EQ(polygon.size(), 4);
    
    // Verify bounding rect
    QRectF bounds = polygon.boundingRect();
    EXPECT_DOUBLE_EQ(bounds.x(), 0.0);
    EXPECT_DOUBLE_EQ(bounds.y(), 0.0);
    EXPECT_DOUBLE_EQ(bounds.width(), 100.0);
    EXPECT_DOUBLE_EQ(bounds.height(), 100.0);
    
    // Test point containment
    QPointF center(50.0, 50.0);
    QPointF outside(150.0, 150.0);
    
    // Note: QPolygonF doesn't have contains() by default, 
    // but we verify the points are accessible
    EXPECT_EQ(polygon[0], QPointF(0, 0));
    EXPECT_EQ(polygon[2], QPointF(100, 100));
}

// Test Rubberbands async operation simulation
TEST(RubberbandsTest, Async_Operation_Simulation)
{
    // Simulate async rubberband update operation
    bool operationComplete = false;
    
    QFuture<bool> future = QtConcurrent::run([&operationComplete]() {
        std::this_thread::sleep_for(std::chrono::milliseconds(5));
        operationComplete = true;
        return true;
    });
    
    future.waitForFinished();
    
    EXPECT_TRUE(operationComplete);
    EXPECT_TRUE(future.result());
}

// Test Rubberbands Qt6 container compatibility
TEST(RubberbandsTest, Qt6_Container_Compatibility)
{
    // Qt6: QList and QVector are identical
    QList<QPointF> points;
    
    points.append(QPointF(0, 0));
    points.append(QPointF(10, 10));
    points.append(QPointF(20, 20));
    
    EXPECT_EQ(points.size(), 3);
    
    // Test range-based for loop
    int index = 0;
    for (const auto& point : points)
    {
        EXPECT_DOUBLE_EQ(point.x(), index * 10.0);
        EXPECT_DOUBLE_EQ(point.y(), index * 10.0);
        ++index;
    }
    
    // Test const access
    const QList<QPointF>& constPoints = points;
    EXPECT_EQ(constPoints[0].x(), 0.0);
}

// Test Rubberbands touch point processing
TEST(RubberbandsTest, Touch_Point_Processing)
{
    // Simulate processing of touch points (Qt6 API)
    QList<QPointF> touchPoints;
    touchPoints << QPointF(100, 200) << QPointF(150, 250) << QPointF(200, 300);
    
    EXPECT_EQ(touchPoints.size(), 3);
    
    // Process points (simulating what Rubberbands does)
    QPointF centroid(0, 0);
    for (const auto& point : touchPoints)
    {
        centroid += point;
    }
    centroid /= touchPoints.size();
    
    EXPECT_DOUBLE_EQ(centroid.x(), 150.0);
    EXPECT_DOUBLE_EQ(centroid.y(), 250.0);
}