node.py

import pygame
import math
from queue import PriorityQueue
from constants import *


# Class to represent every node/spot in the grid
class Node:
    def __init__(self, row, col, width, total_rows):
        self.row = row
        self.col = col
        self.x = row*width
        self.y = col*width
        self.color = GREY 
        self.total_rows = total_rows
        self.neighbors = []
        self.width = width

    def get_pos(self):
        return self.row, self.col

    def is_closed(self):  # To check for already visited nodes signified by red color
        return self.color == RED

    def is_open(self):
        return self.color == GREEN

    def is_barrier(self):
        return self.color == BLACK

    def is_start(self):
        return self.color == ORANGE

    def is_end(self):
        return self.color == TURQUOISE

    def reset(self):
        self.color = GREY

    def make_closed(self):
        self.color = RED

    def make_open(self):
        self.color = GREEN

    def make_barrier(self):
        self.color = BLACK

    def make_end(self):
        self.color = TURQUOISE

    def make_start(self):
        self.color = ORANGE

    def make_path(self):
        self.color = PURPLE

    def draw(self, win):  # Draw a rectangele of given dimensions in the window
        # x,y give the coordinates of the start point with dimensions being height and width
        pygame.draw.rect(
            win, self.color, (self.x, self.y, self.width, self.width))

    def update_neighbors(self, grid):
        self.neighbors = []

        # DOWN : Check if the position below the node in consideration is a barrier, if not add it to its neighbors
        if self.row < self.total_rows - 1 and not grid[self.row + 1][self.col].is_barrier():
            self.neighbors.append(grid[self.row + 1][self.col])

        if self.row > 0 and not grid[self.row - 1][self.col].is_barrier():  # UP
            self.neighbors.append(grid[self.row - 1][self.col])

        if self.col < self.total_rows - 1 and not grid[self.row][self.col + 1].is_barrier(): # RIGHT
            self.neighbors.append(grid[self.row][self.col + 1])

        if self.col > 0 and not grid[self.row][self.col - 1].is_barrier():  # LEFT
            self.neighbors.append(grid[self.row][self.col - 1])