#include <random>
#include <time.h>

#define UP 0
#define LEFT 1
#define RIGHT 2
#define DOWN 3

class Enemy {

public:
    int startPosX;
    int startPosY;
    int boxWidth;
    int boxHeight;
    int boxCurrentPosX;
    int boxCurrentPosY;

    int currentPosX = 123;
    int currentPosY = 123;

    int velocity = 2;

    void move();
    void draw();
    int getRandomDirection();
};

extern Enemy enemy;

int Enemy::getRandomDirection() {
    int direction = rand() % 400;
    if (direction > 0 && direction < 100){
        return UP;
    }
    else if (direction > 100 && direction < 200) {
        return LEFT;
    }
    else if (direction > 200 && direction < 300) {
        return RIGHT;
    }
    else if (direction > 300 && direction < 400) {
        return DOWN;
    }
}

void Enemy::move(){

    bool directionValid = false;
    do
    {
        int tmpVar = 0;
        switch (getRandomDirection())
        {
        case(UP) :
            tmpVar = boxCurrentPosY - 1;
            if (startPosY <= tmpVar)
            {
                boxCurrentPosY = tmpVar;
                currentPosY += velocity;
                directionValid = true;
            }
            break;
        case(DOWN) :
            tmpVar = boxCurrentPosY + 1;
            if ((startPosY + boxHeight) >= tmpVar){
                boxCurrentPosY = tmpVar;
                currentPosY -= velocity;
                directionValid = true;
            }
            break;
        case(LEFT) :
            tmpVar = boxCurrentPosX - 1;
            if (startPosX <= tmpVar)
            {
                boxCurrentPosX = tmpVar;
                currentPosX -= velocity;
                directionValid = true;
            }
            break;
        case(RIGHT) :
            tmpVar = boxCurrentPosX + 1;
            if ((startPosX + boxWidth) >= tmpVar)
            {
                boxCurrentPosX = tmpVar;
                currentPosX += velocity;
                directionValid = true;
            }
            break;
        }
    } while (directionValid == false);
}

void Enemy::draw(){

    // Draw using currentPosX, currentPosY sould be cords.
}

int main()
{
    enemy.startPosX = 0;
    enemy.startPosY = 0;

    enemy.boxWidth = 5;
    enemy.boxHeight = 5;

    enemy.boxCurrentPosX = 0;
    enemy.boxCurrentPosY = 0;

    srand(time(NULL));

    enemy.move();
}