Sloppy gravity with collision

#include "pch.h"
#include <iostream>
#include <SFML/Graphics.hpp>
#include <SFML/Window.hpp>

using namespace std;

int width = 800, height = 600;

int main()
{
    sf::RenderWindow window(sf::VideoMode(width, height), "In Development");
    window.setFramerateLimit(70);
    window.setVerticalSyncEnabled(true);

    sf::RectangleShape player;
    player.setFillColor(sf::Color::Cyan);
    player.setSize(sf::Vector2f(40, 40));
    player.setPosition(width / 2, height / 2);

    sf::RectangleShape bigBlock;
    bigBlock.setSize(sf::Vector2f(100, 100));
    bigBlock.setFillColor(sf::Color::Black);
    bigBlock.setPosition((width / 2) - 300, height / 2);

    int direction = 0;
    float gravity = .3;
    int previousyCoord = NULL;
    sf::Vector2f velocity(0, 0);
    bool onGround = NULL;

    sf::Event event;
    while (window.isOpen())
    {
        while (window.pollEvent(event))
        {
            if (event.type == sf::Event::Closed)
                window.close();
            else if (event.type == sf::Event::KeyPressed)
            {
                if (event.key.code == sf::Keyboard::Right)
                {
                    player.move(5, 0);
                    direction = 1;
                }
                else if (event.key.code == sf::Keyboard::Left)
                {
                    player.move(-5, 0);
                    direction = 2;
                }
                else if(event.key.code == sf::Keyboard::Space)
                {
                    velocity.y = -10;
                }
            }
            else
            {
                direction = 4;
            }
        }

        if (player.getPosition().y > 500)
        {
            player.setPosition(player.getPosition().x, 500);
            velocity.y = 0;
        }
        else
        {
            velocity.y += gravity;
        }

        player.move(velocity);

        sf::FloatRect player_boundingBox = player.getGlobalBounds();
        if (player_boundingBox.intersects(bigBlock.getGlobalBounds()))
        {
            if (direction == 1 && onGround == true)
            {
                player.setPosition(player.getPosition().x, bigBlock.getPosition().y - 40);
            }
            else if (direction == 2 && onGround == true)
            {
                player.setPosition(player.getPosition().x, bigBlock.getPosition().y - 40);
            }
            else if (direction == 1)
                player.setPosition(bigBlock.getPosition().x - 40, player.getPosition().y);
            else if (direction == 2)
                player.setPosition(bigBlock.getPosition().x + 100, player.getPosition().y);
            else if (direction == 4 && previousyCoord <= bigBlock.getPosition().y)
            {
                player.setPosition(player.getPosition().x, bigBlock.getPosition().y - 40);
                onGround = true;
                velocity.y = 0;
            }
        }
        else
            onGround = false;

        window.clear(sf::Color::White); //Clear

        window.draw(bigBlock);
        window.draw(player);

        window.display(); //Display

        cout << direction << " --- " << " OnGround: " << onGround << endl;
        previousyCoord = player.getPosition().y;
    }

    int pause; cin >> pause; //Pause the program
    return 0;
}