import bpy
import math
import bmesh
import random

# This makes it easy to keep revising and running the script
bpy.ops.object.select_all(action='SELECT')
bpy.ops.object.delete(use_global=False)

# ccmp = Color Component
def random_ccmp():
	return random.randrange(0, 1000) / 1000.0

def random_color():
	return (random_ccmp(), random_ccmp(), random_ccmp(), 1.0)

mat = bpy.data.materials.new(name="VertexColorMaterial")
mat.use_nodes = True
bsdf = mat.node_tree.nodes.get("Principled BSDF")
color_node = mat.node_tree.nodes.new(type='ShaderNodeVertexColor')
color_node.layer_name = "Col"
mat.node_tree.links.new(color_node.outputs['Color'], bsdf.inputs['Base Color'])

def point_average(A, B):
    return [(A[0] + B[0]) / 2, ((A[1] + B[1]) / 2), ((A[2] + B[2]) / 2)]

def line_length(A, B): # Works ONLY for axis-aligned lines with only one component different
    return sum([math.fabs(i - j) for i,j in zip(A, B)])

def drawline(A, B):
    M = point_average(A, B)
    length = line_length(A, B)
    if math.fabs(A[0] - B[0]) < math.fabs(A[1] - B[1]):
        new_cylinder = bpy.ops.mesh.primitive_cylinder_add(vertices=4, location=M, scale=(.1, .1, length/2), rotation=(math.radians(90), 0, 0))
    else:
        new_cylinder = bpy.ops.mesh.primitive_cylinder_add(vertices=4, location=M, scale=(.1, .1, length/2), rotation=(0, math.radians(90), 0))


def replace_line(A, B, subdivisions_left=1): 
    I = point_average(A, B)
    H = point_average(A, I)
    J = point_average(I, B)
    direction = 0
    if math.fabs(A[0] - B[0]) > math.fabs(A[1] - B[1]):
        direction = 1
    length = line_length(A, H)

    K = H.copy()
    K[direction] -= length
    L = I.copy()
    L[direction] -= length
    M = I.copy()
    M[direction] += length
    N = J.copy()
    N[direction] += length

    if subdivisions_left > 0:
        replace_line(A, H, subdivisions_left - 1)
        replace_line(H, K, subdivisions_left - 1) 
        replace_line(K, L, subdivisions_left - 1)
        replace_line(I, L, subdivisions_left - 1)    
        replace_line(M, I, subdivisions_left - 1)    
        replace_line(M, N, subdivisions_left - 1)    
        replace_line(N, J, subdivisions_left - 1) 
        replace_line(J, B, subdivisions_left - 1)
    else:
        drawline(A, H)
        drawline(H, K) 
        drawline(K, L)
        drawline(L, I)    
        drawline(I, M)    
        drawline(M, N)    
        drawline(N, J) 
        drawline(J, B)
        


# This runs in the background even when this script has reach the end
def timer_function():
    if bpy.context.mode != "OBJECT":
        return None
    replace_line((-10.0, 0.0, 0.0), (10.0, 0.0, 0.0), 2)

bpy.app.timers.register(timer_function)