from math import pi
from random import uniform

from ipywidgets import Button

from ipycanvas import Canvas, hold_canvas

canvas = Canvas(width=800, height=600)

def recursive_draw_leaf(canvas, length, r_angle, r_factor, l_angle, l_factor):
    canvas.stroke_line(0, 0, 0, -length)
    canvas.translate(0, -length)

    if length > 5:
        canvas.save()

        canvas.rotate(r_angle)
        recursive_draw_leaf(
            canvas, length * r_factor, r_angle, r_factor, l_angle, l_factor
        )

        canvas.restore()

        canvas.save()

        canvas.rotate(l_angle)
        recursive_draw_leaf(
            canvas, length * l_factor, r_angle, r_factor, l_angle, l_factor
        )

        canvas.restore()

def draw_tree(canvas):
    with hold_canvas():
        canvas.save()

        canvas.clear()
        canvas.fill_style = 'white'
        canvas.fill_rect(0, 0, canvas.width, canvas.height)

        canvas.translate(canvas.width / 2.0, canvas.height)

        canvas.stroke_style = "black"

        r_factor = uniform(0.6, 0.8)
        l_factor = uniform(0.6, 0.8)

        r_angle = uniform(pi / 10.0, pi / 5.0)
        l_angle = uniform(-pi / 5.0, -pi / 10.0)

        recursive_draw_leaf(canvas, 150, r_angle, r_factor, l_angle, l_factor)

        canvas.restore()

button = Button(description="Generate tree!")


def click_callback(*args, **kwargs):
    global canvas

    draw_tree(canvas)


button.on_click(click_callback)

draw_tree(canvas)

canvas

button