#include <iostream>
#include <thread>
#include <chrono>
#include <string>

void init(int pixels[], int width) {
    for (int i = 0; i < (width * width); i++) {
        pixels[i] = 0;
    }
}

void clear() {
    std::string output = "";
    for (int i = 0; i < 40; i++) {
        output = output + "\n";
    }
    std::cout << output;
}

void render(int pixels[], int width) {
    std::string output = "PowderBox\n";
    for (int i = 0; i < 40; i++) {
        output = output + "\n";
    }
    output = output + "|";
    for (int i = 0; i < (width * width); i++) {
        std::string symbol = std::to_string(pixels[i]);
        if (symbol == "0") {
            symbol = " ";
        }
        if (symbol == "1") {
            symbol = "x";
        }
        if (symbol == "2") {
            symbol = "#";
        }
        output = output + symbol + " ";
        if (i % width == width-1) {
            output = output + "|\n|";
        }
    }
    for (int i = 0; i < (width*2); i++) {
        output = output + "_";
    }
    output = output + "|";
    std::cout << output;
}

void physics(int pixels[], int width) {
    int n;
    for (int i = 0; i < (width * width); i++) {
        n = (width * width) - i;
        if (pixels[n] == 1) {
            if (n + width < width * width) {
                if (pixels[n + width] == 0) {
                    pixels[n + width] = pixels[n];
                    pixels[n] = 0;
                }
                else if (pixels[n + (width - 1)] == 0) {
                    pixels[n + (width - 1)] = pixels[n];
                    pixels[n] = 0;
                }
                else if (pixels[n + (width + 1)] == 0) {
                    pixels[n + (width + 1)] = pixels[n];
                    pixels[n] = 0;
                }
            }
        }
        if (pixels[n] == 2) {
            if (pixels[n + width] == 0) {
                pixels[n + width] = pixels[n];
                pixels[n] = 0;
            }
        }
    }
}

void simulate(int pixels[], int width) {
    std::chrono::milliseconds timespan(100);
    int c = 0;
    while (1) {
        physics(pixels, width);
        render(pixels, width);
        std::this_thread::sleep_for(timespan);
        if (c == 2) {
            int pos = width / 3;
            pixels[pos-width] = 1;
            pixels[pos+1] = 1;
            pixels[pos+width] = 1;
            pixels[pos-1] = 1;
            pixels[pos-width*2] = 1;
            c = 0;
        }

        c++;
    }
}

int main()
{
    int width = 30;
    std::cout << "Powderbox by Axolay\n";
    std::cout << "Enter sandbox size\n(Recommended: 5<n<35)\nn = ";
    std::cin >> width;
    int pixels[10000];
    init(pixels, width);
    render(pixels, width);
    std::thread physx(simulate, pixels, width);
    while (1) {
        int pixel;
        std::cin >> pixel;
        pixels[pixel] = 1;
        render(pixels, width);
    }
    physx.join();
};