"""Prep example from scratch to make sure we have a unique pipeline"""
import mne
import os
from mne.datasets import sample
from mne.minimum_norm import apply_inverse, make_inverse_operator

# Paths
data_path = sample.data_path()
subject = 'sample'
subjects_dir = os.path.join(data_path, 'subjects')
sample_dir = os.path.join(data_path, 'MEG', subject)

# Functional pipeline
raw_fname = sample_dir + '/sample_audvis_filt-0-40_raw.fif'
events_fname = sample_dir + '/sample_audvis_filt-0-40_raw-eve.fif'
raw = mne.io.read_raw_fif(raw_fname)
events = mne.read_events(events_fname)
epochs = mne.Epochs(raw, events, tmin=-.100, tmax=.200)
cov = mne.compute_covariance(epochs, tmax=0)
evo = epochs.average()

# Structural pipeline
trans_fname = sample_dir + '/sample_audvis_raw-trans.fif'
src = mne.setup_source_space(subject, spacing='oct6',
                             subjects_dir=subjects_dir, 
                             add_dist=False)
morph = mne.compute_source_morph(src,
                                 subject_to='fsaverage',
                                 subjects_dir=subjects_dir)
model = mne.make_bem_model(subject=subject, 
                           ico=4,
                           conductivity=(.3,),
                           subjects_dir=subjects_dir)
bem = mne.make_bem_solution(model)
fwd = mne.make_forward_solution(epochs.info, 
                                trans=trans_fname, 
                                src=src, bem=bem,
                                meg=True, eeg=False, mindist=5.0, n_jobs=-1)

# Inverse modeling
inv = make_inverse_operator(epochs.info, fwd, cov, loose=0., depth=0.8)
stc = apply_inverse(evo, inv)
# -----

# morphing from stc to stc works
morph = mne.compute_source_morph(stc,
                                 subject_from=subject,
                                 subject_to='fsaverage',
                                 subjects_dir=subjects_dir)

stc_success = morph.apply(stc)

# morphing from src to stc does not
morph = mne.compute_source_morph(src,
                                 subject_from=subject,
                                 subject_to='fsaverage',
                                 subjects_dir=subjects_dir)
stc_fails = morph.apply(stc)