# This file was extracted from the HV SDK Docusaurus examples.
# It is intended as a downloadable, runnable companion to the documentation.
# Set HSI_EXAMPLE_BASE_DIR and related env vars to use your own data.
# Source page: /hsi/hv_sdk/examples/basics#read-lines-bands-and-regions

# region: setup
import os
from pathlib import Path

import numpy as np
import qtec_hv_sdk as hs


BASE_DIR = Path(os.environ.get("HSI_EXAMPLE_BASE_DIR", "/path/to/HSI_data/nuts"))
if not BASE_DIR.exists():
    raise SystemExit(
        "Run: 'export HSI_EXAMPLE_BASE_DIR=/path/to/HSI_data/' to setup the "
        "folder containing the example datacubes."
    )
CUBE = os.environ.get("HSI_EXAMPLE_CUBE", "mix1.pam")
# end region

# region: example
cube = hs.open(str(BASE_DIR / CUBE))

line_index = 100
band_index = 164
x0, x1 = 300, 500
y0, y1 = 200, 350

line = cube.array_plane(line_index, hs.lines)

band = cube.array_plane(band_index, hs.bands)
band_from_slice = cube[:, :, band_index].to_numpy_with_interleave(hs.bip)[:, :, 0]
assert np.array_equal(band, band_from_slice)

region = cube[y0:y1, x0:x1, :].to_numpy_with_interleave(hs.bip)

print(f"Line shape: {line.shape}")       # bands x samples
print(f"Band shape: {band.shape}")       # lines x samples
print(f"Region shape: {region.shape}")   # lines x samples x bands
# end region