#Import modules
import numpy as np
import random
from random import random as nprnd
import matplotlib.pyplot as plt

#Initialization - definition of variables
L = 8 # this is the side length of the matrix
center = int(L*(1/2))
mat = np.zeros((L, L)) #matrix of 60 by 60
mat [center, center] = 1 #define center as 1
#walker = (x, y) #where the walker will be
Nwalker_max = 10 #this is what we called “max required stationary points” -- how many dots total
n = 1 #Intial number of walkers (the stationary dot)

def create(): #func that creates a walker, and converts randomly generated side and position within that side to an ORIGINAL position x and y
    side = random.randint(0, 3) # Choose side. This is not done. he said we have to make python know which side is which, so that it know that leftmost column is side =0, upmost row is side 1, rightmost column is side 2, downmost row is side 3
    pos = random.randint(0, L-1) #choose a random position

    if (side == 0):
        x = pos
        y = 0
    elif (side == 1):
        x = 0
        y = pos
    elif (side == 2):
        x = pos
        y = L-1
    else:
        x = L -1
        y = pos
    return (x, y)


for i in (1, Nwalker_max): #a for loop that keeps adding walkers (walkers = new dots)
    walker = create() #matches the walker’s position x, y as that generated by the function create
    x,y = walker
    print(x,y)
    while (True): #
        walker_direction = random.randint(0, 3)# walker direction -- important for boundary verification
        print(walker_direction)
        if walker_direction == 0:
            delta_x, delta_y = 0, 1
        elif walker_direction == 1:
            delta_x, delta_y = 0, -1
        elif walker_direction == 2:
            delta_x, delta_y = 1, 0
        else:
            delta_x, delta_y = -1, 0
        #print(delta_x, delta_y)



        if x + delta_x in range (0, L) and y+delta_y in range (0, L):  #if the motion is allowed, continue; if not, interrupt
            if mat[x+delta_x, y+delta_y] == 1:
                mat[x, y] = 1
                break
            x, y = x+delta_x, y+delta_y
            print(x+delta_x, y+delta_y)
            continue
        else:
                delta_x, delta_y = 0, 0