from nipype.interfaces.base import (traits, File, Directory, TraitedSpec,
                                    OutputMultiPath)
import os.path as op
import glob
from nipype.interfaces.freesurfer.base import FSCommand, FSTraitedSpec
from nipype.utils.filemanip import list_to_filename
import logging

logging.basicConfig()
iflogger = logging.getLogger('interface')


class WatershedBEMInputSpec(FSTraitedSpec):
    subject_id = traits.Str(argstr='--subject %s', mandatory=True,
                           desc='Subject ID (must have a complete Freesurfer directory)')
    subjects_dir = Directory(exists=True, mandatory=True, usedefault=True,
                           desc='Path to Freesurfer subjects directory')
    volume = traits.Enum('T1', 'aparc+aseg', 'aseg', 'brain', 'orig', 'brainmask', 'ribbon',
                           argstr='--volume %s', usedefault=True,
                           desc='The volume from the "mri" directory to use (defaults to T1)')
    overwrite = traits.Bool(True, usedefault=True, argstr='--overwrite',
                            desc='Overwrites the existing files')
    atlas_mode = traits.Bool(argstr='--atlas',
                            desc='Use atlas mode for registration (default: no rigid alignment)')


class WatershedBEMOutputSpec(TraitedSpec):
    mesh_files = OutputMultiPath(File(exists=True),
                           desc=('Paths to the output meshes (brain, inner '
                                 'skull, outer skull, outer skin)'))
    brain_surface = File(exists=True, loc='bem/watershed',
                           desc='Brain surface (in Freesurfer format)')
    inner_skull_surface = File(exists=True, loc='bem/watershed',
                           desc='Inner skull surface (in Freesurfer format)')
    outer_skull_surface = File(exists=True, loc='bem/watershed',
                           desc='Outer skull surface (in Freesurfer format)')
    outer_skin_surface = File(exists=True, loc='bem/watershed',
                           desc='Outer skin surface (in Freesurfer format)')
    fif_file = File(exists=True, loc='bem', altkey='fif',
                           desc='"fif" format file for EEG processing in MNE')
    cor_files = OutputMultiPath(File(exists=True), loc='bem/watershed/ws',
                                altkey='COR', desc='"COR" format files')


class WatershedBEM(FSCommand):
    """Uses mne_watershed_bem to get information from dicom directories

    Examples
    --------

    >>> from nipype.interfaces.mne import WatershedBEM
    >>> bem = WatershedBEM()
    >>> bem.inputs.subject_id = 'subj1'
    >>> bem.inputs.subjects_dir = '.'
    >>> bem.cmdline
    'mne_watershed_bem --overwrite --subject subj1 --volume T1'
    >>> bem.run() 				# doctest: +SKIP

   """

    _cmd = 'mne_watershed_bem'
    input_spec = WatershedBEMInputSpec
    output_spec = WatershedBEMOutputSpec
    _additional_metadata = ['loc', 'altkey']

    def _get_files(self, path, key, dirval, altkey=None):
        globsuffix = '*'
        globprefix = '*'
        keydir = op.join(path, dirval)
        if altkey:
            key = altkey
        globpattern = op.join(keydir, ''.join((globprefix, key, globsuffix)))
        return glob.glob(globpattern)

    def _list_outputs(self):
        outputs = self.output_spec().get()
        subjects_dir = self.inputs.subjects_dir
        subject_path = op.join(subjects_dir, self.inputs.subject_id)
        output_traits = self._outputs()
        mesh_paths = []
        for k in outputs.keys():
            if k != 'mesh_files':
                val = self._get_files(subject_path, k,
                                      output_traits.traits()[k].loc,
                                      output_traits.traits()[k].altkey)
                if val:
                    value_list = list_to_filename(val)
                    if isinstance(value_list, list):
                        out_files = []
                        for value in value_list:
                            out_files.append(op.abspath(value))
                    elif isinstance(value_list, str):
                        out_files = op.abspath(value_list)
                    else:
                        raise TypeError
                    outputs[k] = out_files
                    if not k.rfind('surface') == -1:
                        mesh_paths.append(out_files)
        outputs['mesh_files'] = mesh_paths
        return outputs
