//Аношин Сергей
#include <iostream>
#include <SFML/Graphics.hpp>
#include <cmath>
#include <cstdlib>
#define PI 3,1415

using namespace sf;
using namespace std;

int WIN_HEIGHT = 720;
int WIN_WIDTH = 1080;
int X_ZERO = WIN_WIDTH / 2;
int Y_ZERO = WIN_HEIGHT / 2;

void axes(RenderWindow& window, Font& font) {
    VertexArray axis_x(Lines, 2);
    axis_x[0] = Vector2f(0, Y_ZERO);
    axis_x[1] = Vector2f(WIN_WIDTH, Y_ZERO);
    axis_x[0].color = axis_x[1].color = Color::Black;

    VertexArray axis_y(Lines, 2);
    axis_y[0] = Vector2f(X_ZERO, WIN_HEIGHT);
    axis_y[1] = Vector2f(X_ZERO, 0);
    axis_y[0].color = axis_y[1].color = Color::Black;
    /*
    Vertex arrows[6];
    int size = WIN_WIDTH / 100;
    arrows[0] = Vertex(Vector2f(WIN_WIDTH - size, Y_ZERO + size / 2));
    arrows[1] = Vertex(Vector2f(WIN_WIDTH, Y_ZERO));
    arrows[2] = Vertex(Vector2f(WIN_WIDTH - size, Y_ZERO - size / 2));
    arrows[0].color = arrows[1].color = arrows[2].color = Color::Black;

    arrows[3] = Vertex(Vector2f(X_ZERO - size / 2, size));
    arrows[4] = Vertex(Vector2f(X_ZERO, 0));
    arrows[5] = Vertex(Vector2f(X_ZERO + size / 2, size));
    arrows[3].color = arrows[4].color = arrows[5].color = Color::Black;
    */
    Text text;
    text.setFont(font);
    text.setString("axis X");
    text.setCharacterSize(16);
    text.setFillColor(Color::Black);
    text.setStyle(Text::Regular);
    text.setPosition(WIN_WIDTH - 50, Y_ZERO + 10);
    window.draw(text);

    text.setFont(font);
    text.setString("axis Y");
    text.setCharacterSize(14);
    text.setFillColor(Color::Black);
    text.setStyle(Text::Regular);
    text.setPosition(X_ZERO + 10, 10);
    window.draw(text);

    window.draw(axis_x);
    window.draw(axis_y);
    //window.draw(arrows, 6, Triangles);
}

void ln(RenderWindow& window, int x_strain, int y_strain, int x_displace, int y_displace) {
    double step = WIN_WIDTH / 1000;
    double k = 10;
    VertexArray ln(LineStrip, 1000);
    for (int i = 0; i < 1000; i++) {
        ln[i].position.x = x_displace + X_ZERO + x_strain * (i * step);
        ln[i].position.y = y_displace + Y_ZERO - y_strain * log(i / k);
        ln[i].color = Color::Red;
    }
    window.draw(ln);


    /*
    double step = WIN_WIDTH / 300;
    Vertex curve[500];
    double k = 10;
    double t = 50;
    for (int i = 1; i < 500; i++) {
        curve[i] = Vertex(Vector2f((X_ZERO + i * step), (Y_ZERO - t * log(i / k))));
        curve[i].color = Color::Red;
    }

    for (int i = 0; i < 500; i++) {
        window.draw(curve, 500, Lines);
    }
    */
}
/*
void net(RenderWindow& window) {
    Vertex line[2];
    double step = 50;
    for (int i = 0; i <= WIN_HEIGHT / step; i++) {
        line[0] = Vertex(Vector2f(0, i * step));
        line[1] = Vertex(Vector2f(WIN_WIDTH, i * step));
        line[0].color = line[1].color = Color(168, 168, 168);

        if (i * step != Y_ZERO)
            window.draw(line, 2, Lines);
    }

    for (int i = 0; i <= WIN_WIDTH / step; i++) {
        line[0] = Vertex(Vector2f(i * step, 0));
        line[1] = Vertex(Vector2f(i * step, WIN_HEIGHT));
        line[0].color = line[1].color = Color(168, 168, 168);

        if (i * step != X_ZERO)
            window.draw(line, 2, Lines);
    }

}

void show_lab(RenderWindow& window) {
    int Numb_vert = 5;
    double step = (2 * PI) / (Numb_vert + 1);
    int X_ZERO = WIN_WIDTH / 2;
    int Y_ZERO = WIN_HEIGHT / 2;
    int R = 300;
    int r = 30;
    CircleShape circle(r);
    for (int i = 0; i <= Numb_vert; i++) {
        circle.setPosition(X_ZERO + cos(i * step), Y_ZERO - sin(i * step));
        circle.setFillColor(Color(230, 0, 230));
        window.draw(circle);
    }

}
*/
int main() {
    int x_strain; //1
    int y_strain; //40

    cout << "enter x_strain" << endl;
    cin >> x_strain;

    cout << "enter y_strain" << endl;
    cin >> y_strain;

    int x_displace = 0;
    int y_displace = 0;

    RenderWindow window(VideoMode(WIN_WIDTH, WIN_HEIGHT), "Graph");
    Font font;
    if (!font.loadFromFile("Roboto-Black.ttf"))
    {
        cout << "loading error" << endl;
    }


    while (window.isOpen()) {
        // Конструктор обработчика событий
        Event event;
        while (window.pollEvent(event)) {
            if (event.type == Event::KeyPressed) {
                if (event.key.code == Keyboard::Right)
                    x_displace += 5;

                if (event.key.code == Keyboard::Left)
                    x_displace += -5;

                if (event.key.code == Keyboard::Up)
                    y_displace += -5;

                if (event.key.code == Keyboard::Down)
                    y_displace += 5;
            }

            if (event.type == Event::Closed)
                window.close();
        }
        // Вызовы функций
        window.clear(Color::White);
        //net(window);
        ln(window, x_strain, y_strain, x_displace, y_displace);
        //show_lab(window);
        axes(window, font);
        window.display();

    }
    system("pause");
    return 0;
}