#include <stdlib.h>
#include <ncurses.h>

#include "include/main.h"
#include "include/segment.h"
#include "include/snake.h"
#include "include/field.h"
#include "include/apple.h"
#include "../config.h"

Snake *new_snake(size_t len, int x, int y) {
    Snake *s;
    s = (Snake *)malloc(sizeof(Snake)); if (!s)
        die("snake.c: new_snake(): 's' is null pointer");

    s->len = len;
    s->n = (Segment **)malloc(sizeof(Segment *) * s->len);
    if (!s->n)
        die("snake.c: new_snake(): 's->n' is null pointer");
    for (size_t i = 0; i < s->len; i++)
        s->n[i] = new_segment(x, y++);

    return s;
}

void delete_snake(Snake *s) {
    for (size_t i = 0; i < s->len; i++)
        delete_segment(s->n[i]);
    free_s(s);
}

void snake_forward(Snake *s , int dirn) {
    if (!s)
        die("snake.c: snake_forward(): 's' is null pointer");

    switch (dirn) {
        case UP:
            segment_move(s->n[0], s->n[0]->x, s->n[0]->y - 1);
        break;
        case DOWN:
            segment_move(s->n[0], s->n[0]->x, s->n[0]->y + 1);
        break;
        case RIGHT:
            segment_move(s->n[0], s->n[0]->x + 1, s->n[0]->y);
        break;
        case LEFT:
            segment_move(s->n[0], s->n[0]->x - 1, s->n[0]->y);
        break;
    }

    for (size_t i = 1; i < s->len; i++)
        segment_move(s->n[i], s->n[i - 1]->prev_x,
                              s->n[i - 1]->prev_y);
    
}

void snake_print(Snake *s) {
    if (!s)
        die("snake.c: snake_print(): 's' is null pointer");

    for (size_t i = 0; i < s->len; i++)
        mvaddch(s->n[i]->y, s->n[i]->x, snake_ch);
}

int snake_eat(Snake *s, Field *f) {
    size_t i;
    Segment *c;

    if (field_xy_is_apple(f, s->n[0]->x, s->n[0]->y, &i)) {
        if (!field_relocate_apple(f, i))
            return 0;

        c = new_segment(s->n[s->len - 1]->prev_x, s->n[s->len - 1]->prev_y);

        s->n = (Segment **)realloc(s->n, sizeof(Segment *) * ++(s->len));
        if (!s->n)
            die("snake.c: snake_eat(): 's->n' is null pointer");

        s->n[s->len - 1] = c;

        return 1;
    }

    return 0;
}