"""
===========================
ImGui Integration Example
===========================

This example demonstrates how to integrate an ImGui user interface
into a FURY scene using the :class:`fury.window.ShowManager` and
``imgui_draw_function`` callback.

A small ImGui window is created with a checkbox that controls the
visibility of a group of colored spheres rendered by FURY.

"""

import numpy as np
from imgui_bundle import imgui

from fury.actor import sphere
from fury.window import Scene, ShowManager


###############################################################################
# First, we define an ImGui draw function.
#
# This function will be called every frame by the :class:`ShowManager`.
# Inside it, we build a simple ImGui window with a checkbox that can
# toggle the visibility of our actor.


def create_imgui_controls():
    # Set the initial position and size of the ImGui window. The
    # ``first_use_ever`` condition ensures this is only applied the
    # first time the window appears.
    imgui.set_next_window_pos((10, 10), imgui.Cond_.first_use_ever)
    imgui.set_next_window_size((220, 120), imgui.Cond_.first_use_ever)

    expanded, _ = imgui.begin("Controls")
    if expanded:
        # The checkbox returns (changed, value); we only need the value.
        _, visible = imgui.checkbox("Show spheres", sphere_actor.visible)
        sphere_actor.visible = visible

    imgui.end()


###############################################################################
# Now we create some simple data and build the FURY actor.
#
# We will render three spheres at different positions, each with a
# different color (red, green, blue). These are combined into a single
# FURY actor that we add to the scene.

points = np.asarray(
    [
        (15.0, 0.0, 0.0),
        (0.0, 15.0, 0.0),
        (0.0, 0.0, 15.0),
    ],
    dtype=float,
)

radii = 15.0

colors = np.asarray(
    [
        (1.0, 0.0, 0.0),
        (0.0, 1.0, 0.0),
        (0.0, 0.0, 1.0),
    ],
    dtype=float,
)

sphere_actor = sphere(
    points,
    radii=radii,
    colors=colors,
    phi=48,
    theta=48,
)


###############################################################################
# Next, we create the :class:`Scene` and add our actor to it.

scene = Scene()
scene.add(sphere_actor)


###############################################################################
# Finally, we create a :class:`ShowManager` and enable ImGui support.
#
# Passing ``imgui=True`` turns on ImGui integration, and the
# ``imgui_draw_function`` argument specifies which function will be
# used to define the ImGui user interface each frame.

show_m = ShowManager(
    title="FURY ImGui Integration Example",
    scene=scene,
    size=(800, 600),
    window_type="default",
    imgui=True,
    imgui_draw_function=create_imgui_controls,
)
show_m.start()