#include <stdio.h>
#include <unistd.h>
#include <termios.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <time.h>
#include "./globals.h"
#include "./utils/utils.h"
#include "./snake/snake.h"

void mvSnakeParts(snakePart* head);

char board[BRD_SIZE_Y][BRD_SIZE_X];

const char SNAKE_VIS = '#';

int main() {
  clock_t initClock = clock();

  // Termios setup
  struct termios attr;

  tcgetattr(STDIN_FILENO, &attr);

  const struct termios ATTR_ORIG = attr;

  attr.c_lflag &= ~(ECHO | ICANON);
  attr.c_cc[VMIN] = 0;
  attr.c_cc[VTIME] = 0;

  tcsetattr(STDIN_FILENO, 0,&attr);

  // Game board setup
  for (int i = 0; i < BRD_SIZE_Y; i++) {
    for (int j = 0; j < BRD_SIZE_X; j++) {
      if (i == 0 || i == BRD_SIZE_Y - 1)
        board[i][j] = '-';
      else if (j == 0 || j == BRD_SIZE_X - 1)
        board[i][j] = '|';
      else
        board[i][j] = ' ';
    }
  }

  board[0][0] = '+';
  board[BRD_SIZE_Y - 1][0] = '+';
  board[0][BRD_SIZE_X - 1] = '+';
  board[BRD_SIZE_Y - 1][BRD_SIZE_X - 1] = '+';

  int points = 0;

  // Snake head setup
  snakePart* snakeHead = (snakePart*) malloc(sizeof(snakePart));
  snakeHead->x = randomX(initClock);
  snakeHead->y = randomY(initClock);
  snakeHead->visChar = SNAKE_VIS;
  snakeHead->dir = 'w';
  snakeHead->order = (order*) malloc(sizeof(order));
  snakeHead->order->dir = snakeHead->dir;
  snakeHead->order->delay = -1;
  snakeHead->order->next = NULL;
  snakeHead->next = NULL;

  board[snakeHead->y][snakeHead->x] = snakeHead->visChar;

  // Food setup
  struct {
    int x;
    int y;
    char visChar;
  } food;
  food.x = randomX(initClock);
  food.y = randomY(initClock);
  food.visChar = '$';

  board[food.y][food.x] = food.visChar;

  // Screen init
  system("clear");

  // Game loop
  while (1) {
    fflush(stdout);
    char buf[1] = {0};

    if (snakeHead->x == food.x
        && snakeHead->y == food.y) {
      points++;
      food.x = randomX(initClock);
      food.y = randomY(initClock);
      board[food.y][food.x] = food.visChar;
      addSnakePart(snakeHead);
    }

    if (read(STDIN_FILENO, buf, 1) != 0 && isalpha(buf[0])) {
      char input = buf[0];

      input = tolower(input);

      if (
          (input == 'w' && snakeHead->dir != 's')
          || (input == 's' && snakeHead->dir != 'w')
          || (input == 'a' && snakeHead->dir != 'd')
          || (input == 'd' && snakeHead->dir != 'a')
          ) {
        snakeHead->dir = input;
        addOrders(snakeHead, input);
      }
    }

    mvSnakeParts(snakeHead);

    system("clear");
    printBoard();
    printf("Points: %d\n", points);
    printf("x: %d\n", snakeHead->x);
    printf("y: %d\n\n", snakeHead->y);
    printf("food x: %d\n", food.x);
    printf("food y: %d\n", food.y);

    /*
    {
      snakePart* current = snakeHead;
      int i = 0;
      while (1) {
        printf("Part %d:\n", i);
        printf("dir: %c\n", current->dir);
        printf("orders: \n");
        order* order = current->order;
        int order_i = 0;
        while (1) {
          printf("\t\nOrder %d:\n", order_i);
          printf("\tdir: %c\n", order->dir);
          printf("\tdelay: %d\n", order->delay);
          printf("\tnext: ");
          if (order->next == NULL)
            printf("NULL\n");
          else
            printf("exists\n");
          
          if (order->next == NULL)
            break;

          order = order->next;

          order_i++;
        }
        if (current->next == NULL)
          break;

        current = current->next;
        i++;
      }
    }
    */

    sleep_ms(200);
  }

  // Termios reset
  tcsetattr(STDIN_FILENO, 0, &ATTR_ORIG);

  return 0;
}

void mvSnakeParts(snakePart* head) { 
  snakePart* part = head;
  while (1) {

    order* orderHead = part->order;

    if (orderHead->next != NULL) {
      if (orderHead->next->delay == 0) {
        part->dir = orderHead->next->dir;
        removeOrder(orderHead);
      }
    }

    if (orderHead->next != NULL) {
      order* current = orderHead->next;
      while (1) {
        if (current->delay > 0)
          current->delay--;
        if (current->next == NULL)
          break;
        current = current->next;
      }
    }

    int x = part->x;
    int y = part->y;

    board[y][x] = ' ';

    switch (part->dir) {
      case 'w':
        y = y - 1 < PL_BRD_YS ? PL_BRD_YE : y - 1;
        break;
      case 's':
        y = y + 1 > PL_BRD_YE ? PL_BRD_YS : y + 1;
        break;
      case 'a':
        x = x - 2 < PL_BRD_XS ? PL_BRD_XE - 1 : x - 2;
        break;
      case 'd':
        x = x + 2 > PL_BRD_XE ? PL_BRD_XS : x + 2;
        break;
      default:
        printf("ERROR in func mvSnakeParts\n");
        printf("dir: %c\n", part->dir);
        exit(1);
    }

    part->x = x;
    part->y = y;

    board[y][x] = part->visChar;

    if (part->next == NULL)
      return;

    part = part->next;
  }
}