#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <time.h>

#define MAXX 100
#define MAXY 100

#define UP 'w'
#define DOWN 's'
#define RIGHT 'd'
#define LEFT 'a'


typedef struct snake
{
    int headx;
    int heady;
    int tailx;
    int taily;
    char direction;
    char pre_direction;
    int snake_size;

}snake_t;

typedef struct food
{
    int x;
    int y;

}food_t;

typedef struct position
{
    int positionx[MAXX][MAXY];
    int positiony[MAXX][MAXY];
}position_t;

void array(char **ground, int arraysize ,snake_t *s, food_t *f);
void init_food(int x, int y, food_t *f);
void generate_food(char **ground, int arraysize, food_t *f);
void init_snake(snake_t *s);
void move_head(snake_t *s,position_t *p , char keyinput);
//void move_tail(char **ground,snake_t *s,position_t *p);
void control_snake(char **ground,int arraysize,snake_t *s, position_t *p,food_t *f);
void gameover(char **ground,snake_t *s,int arraysize); //4

int main(int argc, char *argv[])
{
   int arraysize = atoi(argv[1]);
     //converting argument to integer
    if (argv[1] == NULL||argc!=2)
    {
        printf("invalid input\n");
        system("exit");
    }

    if (arraysize < 15 || arraysize > 100)
    {
        printf("try another dimension");
        system("exit");
    }

    else
    {
            int i, j;
            arraysize += 2; //adding 2 extra lines/colums to array (?) ama balw a sto terminal
            char **ground = (char **)malloc(arraysize * sizeof(char *));
            for (i = 0; i < arraysize; i++)
            {
                *(ground + i)= (char *)malloc(arraysize * sizeof(char));
            }

            snake_t s;
            init_snake(&s); //1
            food_t f;
            int x,y;
            init_food(x,y,&f);
            array(ground, arraysize ,&s ,&f);

            generate_food(ground, arraysize, &f);
                while(1)
        {
            position_t p;
            char keyinput;
            move_head(&s,&p,keyinput);
            control_snake(ground,arraysize,&s,&p,&f);//3
            //while(1) dilwste to int alive = 1 kai otan xanei apla allazete to se 0 gia na spaei to loop
        }
       /* while(! keyinput)
        {
            if(gameover()) break;
            sleep(1);
        }
        if(gameover())
        {
            printf("gameover!");
            printf("your score is", s->snake_size);
         }
         */


    }

}



void array(char **ground, int arraysize ,snake_t *s, food_t *f)
{
    int x,y;
    init_food(x,y,f);
    generate_food(ground, arraysize, f);

        int i, j;

                for (i = 0; i < arraysize; ++i)
             {

                for (j = 0; j < arraysize; ++j)
                {
                    if (i == 0 || i == arraysize - 1)
                    {
                        ground[i][j] = '-';
                    }
                    else if (j == 0 || j == arraysize - 1)
                    {
                        ground[i][j] = '|';
                    }
                    else if (f->x == j && f->y == i)
                    {
                        ground[i][j] = 'X';
                    }
                    else
                    {
                        ground[i][j] = ' ';
                    }
                }
             }
                for (i = 0; i < arraysize; ++i)
             {
                for (j = 0; j < arraysize; ++j)
                {
                    printf("%c", ground[i][j]);
                }
                printf("\n");
             }
            }


void init_food(int x, int y, food_t *f)
{
    f->x = x;
    f->y = y;
}

void generate_food(char **ground,int arraysize, food_t *f)
{
    int x,y;

    x = rand()%(arraysize-1);
    y = rand()%(arraysize-1);

    for(x=0; x<arraysize-1; x++)
    {
        for(y=0; y<arraysize-1; y++)
        {
                while(ground[x][y] != ' ')
            {
                x = rand()%(arraysize-1);
                y = rand()%(arraysize-1);

                sleep(1);
            }
                f->x = x;
                f->y = y;
                ground[f->x][f->y] = 'X';

        }
    }



}

void init_snake(snake_t *s) //1
{
    s->tailx =5;
    s->taily = 5;
    s->headx = s->tailx + s->snake_size;
    s->heady = 5;
    s->direction = 's';
    s->pre_direction = 'a';

}

char move()
{
    int flags;
    char key[2];

    flags = fcntl(STDIN_FILENO, F_GETFL);
    fcntl(STDIN_FILENO, F_SETFL, flags | O_NONBLOCK);

    // To get the input from the terminal without pressing the enter button
    system("/bin/stty raw");
    read(STDIN_FILENO, key, 2);
    // Reset the "system ("/bin/stty raw")" to display correctly the output
    system("/bin/stty cooked");
    return key[0];
}

void control_snake(char **ground, int arraysize,snake_t *s, position_t *p,food_t *f) //2
{
    char keyinput = move();
    move_head(s,p,keyinput);
    if(s->headx == f -> x && s -> heady == f->y)
    {
        s -> snake_size++;
        generate_food(ground, arraysize, f);

    }
    else
    {
        //move_tail(ground,s,p);
    }
}

    void move_head(snake_t *s,position_t *p , char keyinput)
    {
        char inserted_key = move();
        if(s->direction == LEFT || s->direction == RIGHT || s->direction == UP || s->direction == DOWN)
        {
            if(inserted_key == LEFT) //elegxos ma pathsw allo koumpi
            {

                s->headx--;

            }
            else if(inserted_key == RIGHT)
            {
                s->headx++;

            }
            else if(inserted_key == UP)
            {
                s->heady++;
            }
            else if(inserted_key == DOWN)
            {
                s->heady--;
            }
        }
        else
        {
            //ground[[p->x][s->size][p->y][s->size]] == '@';
        }
    }




 void gameover(char **ground,snake_t *s,int arraysize)
{
    int i,j;


    for(i = 0; i <= arraysize; i++ )
    {
        for(j=0; j<= arraysize; j++)
        {
            if(s -> headx == '-' || s->headx == '|' || s->headx == '*' ||s->heady == '-' || s->heady == '|' || s->heady == '*')
            {
                printf("game over");
                system("exit");


            }

        }
    }
}