#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <conio.h>
#include <windows.h>
#include <unistd.h>
#include <stdbool.h>
#include <pthread.h>

#define UP 72
#define DOWN 80
#define LEFT 75
#define RIGHT 77

void menuIniziale();
void iniziaGioco();
void sopra();
void sotto();
void sinistra();
void destra();
void * snake(void *);
void gestionePiegamento();
void gameOver();

boolean snakevivo = false, snakespostato = false;

int len, length, bend_no, vite;
char key;

typedef struct
{
    int x;
    int y;
    int dir;
} Coordinate;

Coordinate head, bend[500], cibo, body[30];

int main(int argc, char *argv[]) {
    iniziaGioco();
    return 0;
}

// Functions to go to a certain position
void gotoxy(int x, int y) {
    COORD dwCursorPosition = {x, y};
    SetConsoleCursorPosition( GetStdHandle(STD_OUTPUT_HANDLE), dwCursorPosition);
}

void GotoXY(int x, int y) {
    HANDLE a;
    COORD b;
    fflush(stdout);
    b.X = x;
    b.Y = y;
    a = GetStdHandle(STD_OUTPUT_HANDLE);
    SetConsoleCursorPosition(a,b);
 }

void iniziaGioco() {
    system("cls");
    length = 5; // Initial snake length
    head.x = 25;// Initial coordinates
    head.y = 20;
    head.dir = RIGHT; // Initial snake direction
    vite = 3; // Number of lives
    bend[0] = head;
    snakevivo = true;

    // Let's start threads
    // tSnake = Controlla Snake

    pthread_t tSnake;
    pthread_create(&tSnake, NULL, &snake, NULL);
    pthread_join(tSnake, NULL);

    //movimentoGiocatore();*/
}

// Snake movement functions
///     UP
void sopra() {
   for (int i = 0 ;i <= (bend[bend_no].y - head.y) && len < length; i++) {
        GotoXY(head.x,head.y+i);

        if(len==0) printf("^");
        else printf("*");

        body[len].x = head.x;
        body[len].y = head.y+i;

        len++;
   }

   gestionePiegamento();

   if(!kbhit()) head.y--;
}

///     DOWN
void sotto() {
    for (int i = 0; i <= (head.y - bend[bend_no].y) && len < length; i++) {
        GotoXY(head.x,head.y-i);

        if(len==0) printf("v");
        else printf("*");

        body[len].x = head.x;
        body[len].y = head.y-i;

        len++;
    }

    gestionePiegamento();

    if(!kbhit()) head.y++;
}

///     LEFT
void sinistra() {
    for (int i = 0; i <= (bend[bend_no].x - head.x) && len < length; i++) {
        GotoXY((head.x+i),head.y);

        if(len == 0) printf("<");
        else printf("*");

        body[len].x = head.x+i;
        body[len].y = head.y;

        len++;
    }

    gestionePiegamento();

    if(!kbhit()) head.x--;

}

///     RIGHT
void destra() {
    for (int i = 0; i <= (head.x - bend[bend_no].x) && len < length; i++) {
        GotoXY(body[len].x, body[len].y);

        if(len == 0) printf(">");
        else printf("*");

        body[len].x = head.x-i;
        body[len].y = head.y;

        len++;
    }

    gestionePiegamento();

    if (!kbhit()) head.x++;
}

// Funzione per movement and input
void * snake(void *)
{
    while (snakevivo) {
        fflush(stdin);
        len = 0;

        for (int i=0;i<30;i++)
        {
            body[i].x = 0;
            body[i].y = 0;
            if (i == length) break;
        }

        if (head.dir == RIGHT) destra();
        else if (head.dir == LEFT) sinistra();
        else if (head.dir == DOWN) sotto();
        else if (head.dir == UP) sopra();

        // Input movimento
        key = getch();

        // Controlla se l'input permette un movimento valido
        if((key == RIGHT && head.dir != LEFT &&head.dir != RIGHT)||
        (key == LEFT && head.dir != RIGHT && head.dir != LEFT)||
        (key == UP && head.dir != DOWN && head.dir != UP)||
        (key == DOWN && head.dir != UP && head.dir != DOWN)) {

            bend_no++;
            bend[bend_no] = head;
            head.dir = key;

            switch (key) {
                case UP:
                    head.y--;
                    break;
                case DOWN:
                    head.y++;
                    break;
                case RIGHT:
                    head.x++;
                case LEFT:
                    head.x--;
                    break;
            }
        }

        if (getch() == 27) gameOver();

        snakespostato = true;
        sleep(200);
    }
}

// Function to manage the snake's tail when direction changes
void gestionePiegamento()
{
    int i, j, diff;

    for(i = bend_no; i >= 0 && len < length; i--)
    {
        if(bend[i].x == bend[i-1].x)
        {
            diff=bend[i].y-bend[i-1].y;

            if(diff < 0) {
                for(j = 1; j <= (-diff); j++) {
                    body[len].x = bend[i].x;
                    body[len].y = bend[i].y+j;

                    GotoXY(body[len].x,body[len].y);
                    printf("*");
                    len++;

                    if (len == length) break;
                }
            }
            else if (diff > 0) {
                for(j = 1; j <= diff;j++)
                {
                    body[len].x = bend[i].x;
                    body[len].y = bend[i].y-j;

                    GotoXY(body[len].x,body[len].y);
                    printf("*");
                    len++;

                    if (len == length) break;
                }
            }
        }
        else if (bend[i].y == bend[i-1].y)
        {
            diff = bend[i].x - bend[i-1].x;

            if (diff < 0) {
                for(j = 1;j <= (-diff) && len < length; j++)
                {
                    body[len].x = bend[i].x+j;
                    body[len].y = bend[i].y;

                    GotoXY(body[len].x,body[len].y);
                    printf("*");

                    len++;
                    if (len == length) break;
               }
            }
            else if (diff > 0) {
               for(j = 1; j <= diff && len < length; j++)
                {
                    body[len].x = bend[i].x-j;
                    body[len].y = bend[i].y;

                    GotoXY(body[len].x,body[len].y);
                    printf("*");
                    len++;

                    if (len == length) break;
                }
            }
       }
   }
}