# -*- coding: utf-8 -*-
# emacs: -*- mode: python; py-indent-offset: 4; indent-tabs-mode: nil -*-
# vi: set ft=python sts=4 ts=4 sw=4 et:
import os
import tempfile

import numpy as np

import pytest
from nipype.testing import example_data
import nipype.interfaces.nitime as nitime

no_nitime = not nitime.analysis.have_nitime
display_available = "DISPLAY" in os.environ and os.environ["DISPLAY"]


@pytest.mark.skipif(no_nitime, reason="nitime is not installed")
def test_read_csv():
    """Test that reading the data from csv file gives you back a reasonable
    time-series object """
    CA = nitime.CoherenceAnalyzer()
    CA.inputs.TR = 1.89  # bogus value just to pass traits test
    CA.inputs.in_file = example_data("fmri_timeseries_nolabels.csv")
    with pytest.raises(ValueError):
        CA._read_csv()

    CA.inputs.in_file = example_data("fmri_timeseries.csv")
    data, roi_names = CA._read_csv()
    assert data[0][0] == 10125.9
    assert roi_names[0] == "WM"


@pytest.mark.skipif(no_nitime, reason="nitime is not installed")
def test_coherence_analysis(tmpdir):
    """Test that the coherence analyzer works """
    import nitime.analysis as nta
    import nitime.timeseries as ts

    tmpdir.chdir()
    # This is the nipype interface analysis:
    CA = nitime.CoherenceAnalyzer()
    CA.inputs.TR = 1.89
    CA.inputs.in_file = example_data("fmri_timeseries.csv")
    if display_available:
        tmp_png = tempfile.mkstemp(suffix=".png")[1]
        CA.inputs.output_figure_file = tmp_png
    tmp_csv = tempfile.mkstemp(suffix=".csv")[1]
    CA.inputs.output_csv_file = tmp_csv

    o = CA.run()
    assert o.outputs.coherence_array.shape == (31, 31)

    # This is the nitime analysis:
    TR = 1.89
    data_rec = np.recfromcsv(example_data("fmri_timeseries.csv"))
    roi_names = np.array(data_rec.dtype.names)
    n_samples = data_rec.shape[0]
    data = np.zeros((len(roi_names), n_samples))

    for n_idx, roi in enumerate(roi_names):
        data[n_idx] = data_rec[roi]

    T = ts.TimeSeries(data, sampling_interval=TR)

    assert (CA._csv2ts().data == T.data).all()

    T.metadata["roi"] = roi_names
    C = nta.CoherenceAnalyzer(
        T,
        method=dict(
            this_method="welch", NFFT=CA.inputs.NFFT, n_overlap=CA.inputs.n_overlap
        ),
    )

    freq_idx = np.where(
        (C.frequencies > CA.inputs.frequency_range[0])
        * (C.frequencies < CA.inputs.frequency_range[1])
    )[0]

    # Extract the coherence and average across these frequency bands:
    # Averaging is done on the last dimension
    coh = np.mean(C.coherence[:, :, freq_idx], -1)

    assert (o.outputs.coherence_array == coh).all()
