# -*- coding: utf-8 -*-

#

# Licensed under the terms of the BSD 3-Clause

# (see plotpy/LICENSE for details)

"""

LUT range

---------

The :mod:`plotpy.lutrange` module provides functions to compute and manipulate

the LUT range of plot items.

.. autofunction:: hist_range_threshold

.. autofunction:: lut_range_threshold

"""

from __future__ import annotations

from typing import TYPE_CHECKING

import numpy as np

if TYPE_CHECKING:

from plotpy.items import BaseImageItem, Histogram2DItem

from plotpy.items.histogram import HistDataSource

def hist_range_threshold(

hist: np.ndarray, bin_edges: np.ndarray, percent: float

) -> tuple[float, float]:

"""Return the range corresponding to the given percent of the histogram

Args:

hist (numpy.ndarray): The histogram

bin_edges (numpy.ndarray): The bin edges

percent (float): The percent of the histogram

Returns:

tuple[float, float]: The range

"""

hist = np.concatenate((hist, [0]))

hist = hist[1:]

bin_edges = bin_edges[1:]

threshold = 0.5 * percent / 100 * hist.sum()

i_bin_min = np.cumsum(hist).searchsorted(threshold)

i_bin_max = -1 - np.cumsum(np.flipud(hist)).searchsorted(threshold)

return bin_edges[i_bin_min], bin_edges[i_bin_max]

def lut_range_threshold(

item: BaseImageItem | Histogram2DItem | HistDataSource, bins: int, percent: float

) -> tuple[float, float]:

"""Return the lut range corresponding to the given percent of the histogram

Args:

item (BaseImageItem | Histogram2DItem | HistDataSource): The plot item

bins (int): The number of bins

percent (float): The percent of the histogram

Returns:

tuple[float, float]: The lut range

"""

hist, bin_edges = item.get_histogram(bins)

return hist_range_threshold(hist, bin_edges, percent)