#ifndef SNAKE_H
#define SNAKE_H
#include <QObject>
#include <QQueue>
#include <QPoint>
class QPolygon;

class Snake : public QObject
{
    Q_OBJECT

public:
    enum Direction {Left, Right, Top, Bottom};
    Snake();
    ~Snake();

    QPoint getTail();
    QPoint getHead();
    void setHead(QPoint&);
    int getCountBlocks();
    int getLength();
    const QPolygon* getBlockPositions();
    Direction getDirection();

    void Reset();
    void MoveToLeft();
    void MoveToRight();
    void MoveToTop();
    void MoveToBottom();
    bool Move();
    void AddBlock();
    void ChangeDirection(Direction);

signals:
    void onBlockAddFinish(QPoint);


private:
    QQueue<QPoint>* addedBlocks;
    QPolygon* blockPositions;
    Direction direction;
    void MoveBlocks();
    void CreateStandartSnake();
    bool isCollisionOfSnake();
    void Initialize();
};

#endif // SNAKE_H

#include "snake.h"
#include <QQueue>
#include <QPoint>
#include <QPolygon>
#include <QMessageBox>

Snake::Snake()
{
    Initialize();
}

void Snake::Initialize()
{
    addedBlocks = new QQueue<QPoint>();
    blockPositions = new QPolygon();
    CreateStandartSnake();
    direction = Right;
}

Snake::~Snake()
{
    delete addedBlocks;
    delete blockPositions;
}

void Snake::MoveBlocks()
{
    bool newBlock = false;
    //time to add new block to snake
    if(addedBlocks->count() > 0 && getTail() == addedBlocks->head())
    {
        newBlock = true;
    }

    for(int i = getLength() - 1; i != 0; i--)
    { 
        blockPositions->setPoint(i, blockPositions->point(i-1));
    }

    if (newBlock)
    {
        blockPositions->append(addedBlocks->dequeue());
        emit this->onBlockAddFinish(getTail());
    }
}

void Snake::Reset()
{
    blockPositions->clear();
    addedBlocks->clear();
    Initialize();
}

void Snake::CreateStandartSnake()
{
    blockPositions->append(QPoint(2,0));
    blockPositions->append(QPoint(1,0));
    blockPositions->append(QPoint(0,0));
}

bool Snake::Move()
{
    MoveBlocks();
    switch (direction)
    {
    case Left:
        MoveToLeft();
        break;
    case Right:
        MoveToRight();
        break;
    case Bottom:
        MoveToBottom();
        break;
    case Top:
        MoveToTop();
        break;
    }
    return isCollisionOfSnake();
}

bool Snake::isCollisionOfSnake()
{
    QPoint head = getHead();
    for (int i = 1; i < getLength(); i++)
    {
        if (head == blockPositions->point(i))
        {
            return false;
        }
    }
    return true;
}

void Snake::ChangeDirection(Direction direct)
{
    if ((direction == Left && direct == Right) || (direction == Right && direct == Left))
    {
        return;
    }
    if ((direction == Top && direct == Bottom) || (direction == Bottom && direct == Top))
    {
        return;
    }
    direction = direct;
}

void Snake::setHead(QPoint &point)
{
    blockPositions->setPoint(0,point);
}

void Snake::AddBlock()
{
    addedBlocks->enqueue(getHead());
}

void Snake::MoveToLeft()
{
    QPoint head = getHead();
    head.rx()--;
    blockPositions->setPoint(0,head);
}

void Snake::MoveToRight()
{
    QPoint head = getHead();
    head.rx()++;
    blockPositions->setPoint(0,head);
}

void Snake::MoveToTop()
{
    QPoint head = getHead();
    head.ry()--;
    blockPositions->setPoint(0,head);
}

void Snake::MoveToBottom()
{
    QPoint head = getHead();
    head.ry()++;
    blockPositions->setPoint(0, head);
}

QPoint Snake::getTail()
{
    return blockPositions->point(getLength()-1);
}

QPoint Snake::getHead()
{
    return blockPositions->point(0);
}

int Snake::getCountBlocks()
{
    return blockPositions->count() + addedBlocks->count();
}

int Snake::getLength()
{
    return blockPositions->count();
}

const QPolygon* Snake::getBlockPositions()
{
    return blockPositions;
}

Snake::Direction Snake::getDirection()
{
    return direction;
}

#ifndef GAME_H
#define GAME_H
#include <QObject>
#include "snake.h"
#include "IBlockDraw.h"
#include <QQueue>
#include <QKeyEvent>
#include <QBrush>
#include "statistic.h"
class QPoint;
class QTimer;

class Game : public QObject
{
    Q_OBJECT
public:
    enum Speed {Slow = 200, Medium = 100, Fast = 50};
    Game(int width, int height, IBlockDraw* BlockDraw);
    ~Game();
    int getPoints();
    void Start();
    void End();
    void setSnakeColor(const QBrush&);
    void setBlockColor(const QBrush&);
    void setBackgroundColor(const QBrush&);
    Statistic* getStatistic();
    void KeyPressHandle(QKeyEvent *);
    Speed getSpeed();
    void setSpeed(Speed);
    Snake* snake;
    void SaveResult(QString&);

protected:
    bool isNewBlock();
    void AddNewBlock();

private:
    int points;
    QTimer* moveTimer;
    QQueue<Snake::Direction>* pressedDirections;
    QPoint* block;
    QBrush* backgroundColor;
    QBrush* snakeColor;
    QBrush* blockColor;
    IBlockDraw* blockDraw;
    Statistic statistic;
    int eatPoints;
    int width;
    int height;
    Speed speed;

    bool Move();
    void NewBlock();
    void ClearBlock(const QPoint&);
    void DrawSnakeBlock(const QPoint&);
    void DrawBlock();
    void Draw(const QPoint&, const QBrush&);
    void DrawSnake();
    void DrawBackground();
    void setPoints(int points);
    void AddPoints(int);
    void CheckSnakeOutOfMap();

public slots:
    void MoveByTime();
    void AddSnakeBlockFinish(const QPoint&);


signals:
    void onPointsChanged(int points);
    void onGameOver();
    void onSnakeBlockCountChanged(int legth);

};

#endif // GAME_H

#include "game.h"
#include <QPoint>
#include <QTimer>
#include <QBrush>
#include <QQueue>
#include "snake.h"
#include <QDateTime>


Game::Game(int width, int height, IBlockDraw *BlockDraw)
{
    QString path("statistic.db");
    statistic = Statistic(path);
    eatPoints = 100;
    this->width = width;
    this->height = height;
    blockDraw = BlockDraw;
    moveTimer = new QTimer(this);
    moveTimer->setInterval(Slow);
    moveTimer->stop();
    snake = new Snake();
    backgroundColor = new QBrush(Qt::gray);
    snakeColor = new QBrush(Qt::blue);
    blockColor = new QBrush(Qt::red);
    pressedDirections = new QQueue<Snake::Direction>();
    QObject::connect(moveTimer, SIGNAL(timeout()), this, SLOT(MoveByTime()));
    QObject::connect(snake, SIGNAL(onBlockAddFinish(QPoint)), this, SLOT(AddSnakeBlockFinish(const QPoint&)));
}

Game::~Game()
{
    delete snake;
    delete moveTimer;
    delete pressedDirections;
    delete block;
    delete backgroundColor;
    delete blockColor;
    delete snakeColor;
    delete blockDraw;
}

void Game::Start()
{
    snake->Reset();
    DrawBackground();
    DrawSnake();
    points = 0;
    moveTimer->start();
    //emit onSnakeBlockCountChanged(snake->getCountBlocks());
    NewBlock();
}

void Game::End()
{
    moveTimer->stop();
    //clearing old directions for new game
    pressedDirections->clear();
    pressedDirections = new QQueue<Snake::Direction>();
    emit onGameOver();
}

bool Game::isNewBlock()
{
    QPoint head = snake->getHead();
    if(head.x()== block->x() && head.y() == block->y())
    {
        return true;
    }
    return false;
}

void Game::AddNewBlock()
{
    snake->AddBlock();
    AddPoints(eatPoints);
    NewBlock();
    emit onSnakeBlockCountChanged(snake->getCountBlocks());
}

void Game::MoveByTime()
{
    Move();
}

bool Game::Move()
{
    if (pressedDirections->count() > 0)
    {
        snake->ChangeDirection(pressedDirections->dequeue());
    }

    ClearBlock(snake->getTail());
    if(!snake->Move())
    {
        End();
        return false;
    }

    CheckSnakeOutOfMap();

    if(isNewBlock())
    {
        AddNewBlock();
    }

    DrawSnakeBlock(snake->getHead());
    return true;
}

void Game::NewBlock()
{
    bool contains = false;
    qsrand(QDateTime::currentMSecsSinceEpoch());
    //checking that place new block not on snake
    do
    {
        contains = false;
        block = new QPoint(qrand() % width, qrand() % height);
        if (snake->getBlockPositions()->contains(*block))
        {
            contains = true;
            delete block;
        }
    }
    while(contains);
    DrawBlock();
}

void Game::Draw(const QPoint& point, const QBrush& color)
{
    int x = point.x() * blockDraw->getSize();//+1;
    int y = point.y() * blockDraw->getSize();//+1;
    QPoint p(x,y);
    blockDraw->DrawBlock(p, color);
}

void Game::ClearBlock(const QPoint& p)
{
    Draw(p, *backgroundColor);
}

void Game::DrawSnakeBlock(const QPoint& p)
{
    Draw(p, *snakeColor);
}

void Game::DrawBlock()
{
    Draw(*block, *blockColor);
}

void Game::AddSnakeBlockFinish(const QPoint& block)
{
    DrawSnakeBlock(snake->getTail());
}

void Game::DrawSnake()
{
    const QPolygon* snakeBlocks = snake->getBlockPositions();
    for(int i=0; i<snake->getCountBlocks(); i++)
    {
        DrawSnakeBlock(snakeBlocks->point(i));
    }
}

void Game::DrawBackground()
{
    QPoint point;
    for (int i = 0; i < width+1; i++)
    {
        for (int j = 0; j < height+1; j++)
        {
            point.rx()=i;
            point.ry()=j;
            Draw(point, *backgroundColor);
        }
    }
}

void Game::setPoints(int points)
{
    this->points = points;
    emit onPointsChanged(points);
}

void Game::AddPoints(int points)
{
    this->points+=points;
    emit onPointsChanged(this->points);
}

void Game::setSpeed(Game::Speed sp)
{
    speed = sp;
    moveTimer->setInterval(speed);
}

Game::Speed Game::getSpeed()
{
    return speed;
}

void Game::KeyPressHandle(QKeyEvent* e)
{
    switch (e->key())
    {
    case Qt::Key_Up:
    case Qt::Key_W:
        pressedDirections->enqueue(Snake::Top);
        break;
    case Qt::Key_Left:
    case Qt::Key_A:
        pressedDirections->enqueue(Snake::Left);
        break;
    case Qt::Key_Down:
    case Qt::Key_S:
        pressedDirections->enqueue(Snake::Bottom);
        break;
    case Qt::Key_Right:
    case Qt::Key_D:
        pressedDirections->enqueue(Snake::Right);
        break;
    }
}

void Game::CheckSnakeOutOfMap()
{
    QPoint head = snake->getHead();
    if(head.x() > width)
    {
        QPoint* point = new QPoint(0,head.y());
        snake->setHead(*point);
    }
    if(head.x() < 0)
    {
        QPoint* point = new QPoint(width,head.y());
        snake->setHead(*point);
    }
    if(head.y() > height)
    {
        QPoint* point = new QPoint(head.x(),0);
        snake->setHead(*point);
    }
    if(head.y() < 0)
    {
        QPoint* point = new QPoint(head.x(),height);
        snake->setHead(*point);
    }
}

Statistic * Game::getStatistic()
{
    return &statistic;
}

void Game::setSnakeColor(const QBrush& color)
{
    *snakeColor = color;
}

void Game::setBlockColor(const QBrush& color)
{
    *blockColor = color;
}

void Game::setBackgroundColor(const QBrush& color)
{
    *backgroundColor = color;
}

void Game::SaveResult(QString &name)
{
    statistic.AddRecord(name, points, QDate::currentDate());
}

class A{
B b(args)
}

void foo(QString&);
void main()
{
    foo(QString(""));
}

class MyClass {
public:
 MyClass( const QString & txt = "" ) : mName(txt) {}
 
 QString mName;
}; 
 
class MyClass2 {
public:
 MyClass( const QString & txt = "" ) : mStruct(str) {}
 
 MyStruct mStruct;
}; 

class MyClass2{
public:
    MyClass(const QString& text = ""):mClass(str){}
MyClass mClass;
}

class MyClass
{
 public:
    MyClass(int score): score(score){}
    MyClass():score(0){}
 int score;
}
class MyClass2
{
 public MyClass2(QString& s = ""):myStr(s){}
QString myStr;
MyClass mClass;
}

class Foo
{
public:
    Foo(const QString&s):str(s){}
    QString str;
};

class Foo2
{
public:
    Foo2(){
        foo = Foo(QString("foo"));
    }
    Foo foo;
};

Foo2():foo(QString("foo")){...}

void f(Type* t){};
void main(){
f(new Type());
}

#include <QtCore/QCoreApplication>
#include <QDebug>
#include "windows.h"

class Record{
public:
    int x;//т.к. тест, то всеравно где
    Record()
    {
        x=3;
        qDebug("record created");
    }
    ~Record()
    {
        qDebug("record destructed");
    }
    Record(const Record& r)
    {
        qDebug() << "copy constructor";
    }
};

static Record* r;//будем хранить ссылку передаваемую в функцию

void Test(const Record& rec){
    qDebug("Test start");
    //qDebug()<<"&rec="<<&rec;
    if(&(*r) != &rec)//если новая ссылка не равна старой, выводим и присваиваем
    {
     qDebug()<<"&rec="<<&rec;
     r = const_cast<Record*>(&rec);
    }
    QString s("ldgjfdklgjdfg"), ss("fsfsdfdsfsdf");
    for (int i = 0; i < 10000000; i++)
    {
        s+=ss;//что бы было какое то время для удаления временного обьекта если должен удаляться
    }
    Sleep(1000);//с той же целью
    qDebug("Test end");
}


int main(int argc, char *argv[]){
    QCoreApplication a(argc, argv);
    for(int i=0; i<10; i++)
    {
        Test(Record());
        Sleep(1000);//время что бы могла освободиться память временных обьектов и т.п.
    }
    return a.exec();
}

На стеке отвели место для безымянного Record и вызвали его конструктор. Возможно конструктор там какие-то члены создал в куче - то его дело. Толкнули опять-таки адрес Record на стек и вызвали ф-цию. Ф-ция отработала и вернула упрвление. Вызываем деструктор Record (если есть). Выравниваем стек. Готовченко.