"""
==================
ImageContainer2D
==================

This example demonstrates how to use the ``ImageContainer2D`` UI element
to display 2D images in the FURY rendering window. ``ImageContainer2D``
supports various input formats including local image paths and raw NumPy arrays.

First, let's import the necessary modules.
"""

import numpy as np
from fury.ui import ImageContainer2D
from fury.window import Scene, ShowManager

from fury.data import fetch_viz_cubemaps, read_viz_cubemap

###############################################################################
# Fetch an existing image (a skybox texture) from FURY's datasets
# to use as a file path input.

fetch_viz_cubemaps()
skybox_images = read_viz_cubemap("skybox")
texture_path = skybox_images[0]

###############################################################################
# Generate a 256x256 RGB image array with varying color gradients using NumPy.

img_rgb = np.zeros((256, 256, 3), dtype=np.uint8)
for i in range(256):
    img_rgb[:, i, 0] = i
    img_rgb[i, :, 1] = (i * 2) % 256
    img_rgb[:, :, 2] = 128

###############################################################################
# Generate an RGBA image array, which includes an alpha channel for transparency.

img_rgba = np.zeros((256, 256, 4), dtype=np.uint8)
for i in range(256):
    img_rgba[:, i, 0] = 255 - i
    img_rgba[i, :, 1] = (i * 2) % 256
    img_rgba[:, :, 2] = 128
    img_rgba[:, i, 3] = 255 - i

###############################################################################
# Convert the RGB image into a single-channel grayscale image.

img_gray = (
    0.2989 * img_rgb[..., 0].astype(np.float32)
    + 0.5870 * img_rgb[..., 1].astype(np.float32)
    + 0.1140 * img_rgb[..., 2].astype(np.float32)
).astype(np.uint8)

###############################################################################
# Initialize a Scene and create an ImageContainer2D for each image type.
# Set the position to arrange them in a 2x2 grid on the window.

scene = Scene()

gray_container = ImageContainer2D(
    img_path=img_gray,
    position=(50, 450),
    size=(256, 256),
)

rgb_container = ImageContainer2D(
    img_path=img_rgb,
    position=(350, 450),
    size=(256, 256),
)

rgba_container = ImageContainer2D(
    img_path=img_rgba,
    position=(50, 100),
    size=(256, 256),
)

skybox_container = ImageContainer2D(
    img_path=texture_path,
    position=(350, 100),
    size=(256, 256),
)

###############################################################################
# Add all image containers to the scene.

scene.add(gray_container)
scene.add(rgb_container)
scene.add(rgba_container)
scene.add(skybox_container)

###############################################################################
# Create and start the ShowManager.

show_manager = ShowManager(
    scene=scene,
    size=(700, 800),
    title="FURY ImageContainer2D Example",
)
show_manager.start()