"""Functions for reading and writing SRA-XML."""
import datetime
import hashlib
import html
import iso8601
import jinja2
import logging
import os
import xml.dom.minidom
from functools import partial
from lxml import etree

from isatools import config
from isatools.model import DataFile
from isatools.model import OntologyAnnotation
from isatools.model import Sample

logging.basicConfig(level=config.log_level)
log = logging.getLogger(__name__)

supported_sra_assays = [
    ('genome sequencing', 'nucleotide sequencing'),
    ('environmental gene survey', 'nucleotide sequencing'),
    ('metagenome sequencing', 'nucleotide sequencing'),
    ('transcription profiling', 'nucleotide sequencing')
]

sra_center_name = 'OXFORD'
sra_broker_name = 'ISAcreator'
sra_lab_name = sra_center_name
sra_submission_action = 'ADD'
sra_center_prj_name = None


def export(investigation, export_path, sra_settings=None, datafilehashes=None):

    def get_comment(assay, name):
        hits = [c for c in assay.comments if c.name.lower() == name.lower()]
        if len(hits) > 1:
            raise AttributeError(
                "Multiple comments of label '{}' found".format(name))
        elif len(hits) < 1:
            return None
        else:
            return hits[0]

    def get_sample(process):
        materials = process.inputs
        sample = None
        for material in materials:
            if isinstance(material, Sample):
                sample = material
                break
        return sample

    def get_pv(process, name):
        hits = [pv for pv in process.parameter_values if
                pv.category.parameter_name.term.lower().replace('_', ' ')
                == name.lower().replace('_', ' ')]
        if len(hits) > 1:
            raise AttributeError(
                "Multiple parameter values of category '{}' found".format(name))
        elif len(hits) < 1:
            return None
        else:
            if isinstance(hits[0].value, OntologyAnnotation):
                value = hits[0].value.term
            else:
                value = hits[0].value
            return value.replace('_', ' ')

    global sra_center_name
    global sra_broker_name
    if sra_settings is not None:
        sra_center_name = sra_settings['sra_center']
        sra_broker_name = sra_settings['sra_broker']
        # sra_lab_name = sra_settings['sra_lab_name']
        # sra_submission_action = sra_settings['sra_submission_action']
        # sra_center_prj_name = sra_settings['sra_center_prj_name']

    log.info('isatools.sra.export()')
    for istudy in investigation.studies:
        is_sra = False
        for iassay in istudy.assays:
            if (iassay.measurement_type.term, iassay.technology_type.term) in \
                    supported_sra_assays:
                is_sra = True
                break
        if not is_sra:
            log.info('No SRA assay found, skipping processing')
            continue

        study_acc = istudy.identifier
        log.debug("sra exporter, working on " + study_acc)

        # Flag SRA contacts for template
        has_sra_contact = False
        for contact in istudy.contacts:
            if "sra inform on status" in \
                    [r.term.lower() for r in contact.roles]:
                contact.inform_on_status = True
                has_sra_contact = True
            if "sra inform on error" in [r.term.lower() for r in contact.roles]:
                contact.inform_on_error = True
                has_sra_contact = True
        if not has_sra_contact:
            raise ValueError(
                "The study '{0}' has either no SRA contact or no email "
                "specified for the contact. Please ensure you have one contact "
                "with a 'Role' as 'SRA Inform On Status', otherwise we cannot "
                "export to SRA.".format(istudy.identifier)
            )

        if istudy.submission_date is None or istudy.submission_date == '':
            istudy.submission_date = iso8601.parse_date(
                datetime.date.today().isoformat(), iso8601.UTC).isoformat()
        else:
            istudy.submission_date = iso8601.parse_date(
                istudy.submission_date, iso8601.UTC).isoformat()
        istudy.description = html.escape(istudy.description)
        # ideally make it a requirement in the model or JSON to have html
        # escaped content

        env = jinja2.Environment()
        env.loader = jinja2.FileSystemLoader(
            os.path.join(
                os.path.dirname(__file__), 'resources', 'sra_templates'))
        xsub_template = env.get_template('submission_add.xml')
        sra_contact = None
        if sra_settings is not None:
            inform_on_status = sra_settings['sra_broker_inform_on_status']
            inform_on_error = sra_settings['sra_broker_inform_on_error']
            contact_name = sra_settings['sra_broker_contact_name']
            sra_contact = {
                'inform_on_status': inform_on_status,
                'inform_on_error': inform_on_error,
                'contact_name': contact_name
            }
        xsub = xsub_template.render(accession=study_acc,
                                    contacts=istudy.contacts,
                                    submission_date=istudy.submission_date,
                                    sra_center_name=sra_center_name,
                                    sra_broker_name=sra_broker_name,
                                    sra_contact=sra_contact)
        xproj_template = env.get_template('project_set.xml')
        xproj = xproj_template.render(
            study=istudy, sra_center_name=sra_center_name)

        assays_to_export = list()
        for iassay in istudy.assays:
            if (iassay.measurement_type.term, iassay.technology_type.term) in \
                    supported_sra_assays:
                assay_seq_processes = [
                    a for a in iassay.process_sequence if
                    a.executes_protocol.protocol_type.term ==
                    'nucleic acid sequencing']
                for assay_seq_process in assay_seq_processes:
                    do_export = True
                    if get_comment(assay_seq_process, 'export') is not None:
                        log.debug('HAS EXPORT COMMENT IN ASSAY')
                        export = get_comment(assay_seq_process, 'export').value
                        log.debug('export is {}'.format(export))
                        do_export = export.lower() != 'no'
                    else:
                        log.debug('NO EXPORT COMMENT FOUND')
                    log.debug('Perform export? '.format(str(do_export)))
                    if do_export:
                        sample = None
                        curr_process = assay_seq_process
                        while sample is None:
                            sample = get_sample(curr_process)
                            curr_process = curr_process.prev_process
                        assay_to_export = \
                            {
                                'sample': sample,
                                'sample_alias': '{0}:sample:{1}'.format(
                                    study_acc, sample.name),
                                'run_alias': '{0}:assay:{1}'.format(
                                    study_acc, assay_seq_process.name),
                                'exp_alias': '{0}:generic_assay:{1}'.format(
                                    study_acc, '{0}:{1}'.format(
                                        iassay.filename[:-4],
                                        assay_seq_process.name))
                            }
                        datafiles = list(filter(
                            lambda datafile: isinstance(datafile, DataFile),
                            assay_seq_process.outputs
                        ))
                        checksum = '00000000000000000000000000000000'
                        if datafilehashes is not None:
                            checksum = datafilehashes[datafiles[0].filename]
                            # raises AttributeError if file not found
                        filetype = datafiles[0].filename[
                                   datafiles[0].filename.index('.') + 1:]
                        if filetype.endswith('.gz'):
                            filetype = filetype[:filetype.index('.')]
                        assay_to_export['data_file'] = {
                            'filename': datafiles[0].filename,
                            'filetype': filetype,
                            'checksum': checksum
                        }
                        source = None
                        matching_sources = [
                            p.inputs for p in istudy.process_sequence
                            if sample in p.outputs]
                        if len(matching_sources[0]) == 1:
                            source = matching_sources[0][0]
                        assay_to_export['source'] = {
                            'name': source.name,
                            'characteristics': source.characteristics,
                        }
                        organism_charac = [c for c in source.characteristics
                                           if c.category.term == 'organism'][-1]
                        assay_to_export['source']['taxon_id'] = \
                            organism_charac.value.term_accession[
                            organism_charac.value.term_accession.index('_')+1:]
                        assay_to_export['source']['scientific_name'] = \
                            organism_charac.value.term
                        curr_process = assay_seq_process
                        while curr_process.prev_process is not None:
                            assay_to_export[
                                curr_process.executes_protocol.protocol_type
                                    .term] = curr_process
                            try:
                                curr_process = curr_process.prev_process
                            except AttributeError:
                                pass
                        target_taxon = get_pv(
                            assay_to_export['library construction'],
                            'target_taxon')
                        assay_to_export['target_taxon'] = target_taxon
                        assay_to_export['targeted_loci'] = False
                        assay_to_export['min_match'] = 0
                        # BEGIN genome seq library selection
                        if iassay.measurement_type.term in [
                                'genome sequencing', 'whole genome sequencing']:
                            library_source = get_pv(
                                assay_to_export['library construction'],
                                'library source')
                            if library_source.upper() not in [
                                'GENOMIC', 'GENOMIC SINGLE CELL',
                                'METAGENOMIC', 'OTHER']:
                                log.warning(
                                    'ERROR:value supplied is not compatible '
                                    'with SRA1.5 schema {}'.format(
                                        library_source))
                                library_source = 'OTHER'

                            library_strategy = get_pv(
                                assay_to_export['library construction'],
                                'library strategy')
                            if library_strategy.upper() not in ['WGS', 'OTHER']:
                                log.warning(
                                    'ERROR:value supplied is not compatible '
                                    'with SRA1.5 schema {}'.format(
                                        library_strategy))
                                library_strategy = 'OTHER'

                            library_selection = get_pv(
                                assay_to_export['library construction'],
                                'library selection')
                            if library_selection not in ['RANDOM',
                                                         'UNSPECIFIED']:
                                log.warning(
                                    'ERROR:value supplied is not compatible '
                                    'with SRA1.5 schema '.format(
                                        library_selection))
                                library_selection = 'unspecified'

                            protocol = '\n protocol_description: {}'.format(
                                assay_to_export['library construction']
                                .executes_protocol.description)
                            mid_pv = get_pv(
                                assay_to_export['library construction'], 'mid')
                            if mid_pv is not None:
                                protocol += '\n mid: {}'.format(mid_pv.value)

                            assay_to_export['library_source'] = library_source
                            assay_to_export[
                                'library_strategy'] = library_strategy
                            assay_to_export[
                                'library_selection'] = library_selection
                            assay_to_export[
                                'library_construction_protocol'] = protocol

                            library_layout = get_pv(
                                assay_to_export['library construction'],
                                'library layout')
                            assay_to_export['library_layout'] = \
                                library_layout.lower()
                        # END genome seq library selection
                        # BEGIN environmental gene survey library selection
                        elif iassay.measurement_type.term in \
                                ['environmental gene survey']:
                            assay_to_export['library_source'] = 'METAGENOMIC'
                            assay_to_export['library_strategy'] = 'AMPLICON'
                            assay_to_export['library_selection'] = 'PCR'
                            library_layout = get_pv(
                                assay_to_export['library construction'],
                                'library layout')
                            assay_to_export['library_layout'] = \
                                library_layout.lower()
                            nucl_acid_amp = get_pv(
                                assay_to_export['library construction'],
                                'nucleic acid amplification')
                            if nucl_acid_amp is None:
                                nucl_acid_amp = get_pv(
                                    assay_to_export['library construction'],
                                    'nucl_acid_amp')

                            protocol = '\n protocol_description: '.format(
                                assay_to_export['library construction']
                                    .executes_protocol.description)
                            mid_pv = get_pv(
                                assay_to_export['library construction'], 'mid')
                            if mid_pv is not None:
                                protocol += '\n mid: {}'.format(mid_pv)
                                assay_to_export['barcode'] = mid_pv
                                assay_to_export['min_match'] = len(mid_pv)
                            if nucl_acid_amp is not None:
                                protocol += '\n nucl_acid_amp: {}'\
                                    .format(nucl_acid_amp.value)
                            url = get_pv(
                                assay_to_export['library construction'], 'url')
                            if url is not None:
                                protocol += '\n url: '.format(
                                    nucl_acid_amp.value)
                            target_taxon = assay_to_export['target_taxon']
                            if target_taxon is not None:
                                protocol += '\n target_taxon: {}'.format(
                                    target_taxon)
                            target_gene = get_pv(
                                assay_to_export['library construction'], 
                                'target_gene')
                            if target_gene is not None:
                                protocol += '\n target_gene: {}'.format(
                                    target_gene)
                            target_subfragment = get_pv(
                                assay_to_export['library construction'], 
                                'target_subfragment')
                            if target_subfragment is not None:
                                protocol += '\n target_subfragment: {}'.format(
                                    target_subfragment)
                            pcr_primers = get_pv(
                                assay_to_export['library construction'], 
                                'pcr_primers')
                            if pcr_primers is not None:
                                protocol += '\n pcr_primers: {}'.format(
                                    pcr_primers)
                            pcr_cond = get_pv(
                                assay_to_export['library construction'], 
                                'pcr_cond')
                            if pcr_cond is not None:
                                protocol += '\n pcr_cond: {}'.format(pcr_cond)
                            assay_to_export['library_construction_protocol'] = \
                                protocol

                            if target_gene is not None:
                                assay_to_export['targeted_loci'] = True
                                assay_to_export['locus_name'] = target_gene
                        # END environmental gene survey library selection
                        # BEGIN metagenome seq library selection
                        elif iassay.measurement_type.term in \
                                ['metagenome sequencing']:
                            library_source = 'METAGENOMIC'
                            library_strategy = get_pv(
                                assay_to_export['library construction'], 
                                'library strategy')
                            if library_strategy.upper() not in ['WGS', 'OTHER']:
                                log.warning(
                                    'ERROR:value supplied is not compatible '
                                    'with SRA1.5 schema '.format(
                                        library_strategy))
                                library_strategy = 'OTHER'

                            library_selection = get_pv(
                                assay_to_export['library construction'], 
                                'library selection')
                            if library_selection not in \
                                    ['RANDOM', 'UNSPECIFIED']:
                                log.warning(
                                    'ERROR:value supplied is not compatible '
                                    'with SRA1.5 schema '.format(
                                        library_selection))
                                library_selection = 'unspecified'

                            protocol = '\n protocol_description: {}'.format(
                                assay_to_export['library construction']
                                    .executes_protocol.description)
                            mid_pv = get_pv(
                                assay_to_export['library construction'], 'mid')
                            if mid_pv is not None:
                                protocol += '\n mid: {}'.format(mid_pv.value)

                            assay_to_export['library_source'] = library_source
                            assay_to_export['library_strategy'] = \
                                library_strategy
                            assay_to_export['library_selection'] = \
                                library_selection
                            assay_to_export['library_construction_protocol'] = \
                                protocol

                            library_layout = get_pv(
                                assay_to_export['library construction'], 
                                'library layout')
                            assay_to_export['library_layout'] = \
                                library_layout.lower()
                        # END metagenome seq library selection
                        # BEGIN transciption profiling library selection
                        elif iassay.measurement_type.term in \
                                ['transcription profiling']:
                            library_source = get_pv(
                                assay_to_export['library construction'],
                                'library source')
                            if library_source is None:  
                                # if not specified, select TRANSCRIPTOMIC by 
                                # default
                                library_source = 'TRANSCRIPTOMIC'

                            if library_source.upper() not in \
                                    ['TRANSCRIPTOMIC', 
                                     'TRANSCRIPTOMIC SINGLE CELL',
                                     'METATRANSCRIPTOMIC', 
                                     'OTHER']:
                                log.warning(
                                    'ERROR:value supplied is not compatible '
                                    'with SRA1.5 schema {}'.format(
                                        library_source))
                                library_source = 'OTHER'

                            library_strategy = get_pv(
                                assay_to_export['library construction'],
                                'library strategy')
                            if library_strategy not in \
                                    ['RNA-Seq', 'ssRNA-Seq', 'miRNA-Seq', 
                                     'ncRNA-Seq', 'FL-cDNA', 'EST', 'OTHER']:
                                log.warning(
                                    'ERROR:value supplied is not compatible '
                                    'with SRA1.5 schema {}'.format(
                                        library_strategy))
                                library_strategy = 'OTHER'

                            library_selection = get_pv(
                                assay_to_export['library construction'],
                                'library selection')
                            if library_selection not in \
                                    ['RT-PCR', 'cDNA', 'cDNA_randomPriming', 
                                     'cDNA_oligo_dT', 'PolyA', 'Oligo-dT', 
                                     'Inverse rRNA', 'Inverse rRNA selection',
                                     'CAGE', 'RACE', 'other']:
                                log.warning(
                                    'ERROR:value supplied is not compatible '
                                    'with SRA1.5 schema {}'.format(
                                        library_selection))
                                library_selection = 'other'

                            protocol = '\n protocol_description: {}'.format(
                                assay_to_export['library construction']
                                    .executes_protocol.description)
                            assay_to_export['library_source'] = library_source
                            assay_to_export['library_strategy'] = \
                                library_strategy
                            assay_to_export['library_selection'] = \
                                library_selection
                            assay_to_export['library_construction_protocol'] = \
                                protocol

                            library_layout = get_pv(
                                assay_to_export['library construction'],
                                'library layout')
                            assay_to_export['library_layout'] = \
                                library_layout.lower()
                        # END transciption profiling library selection
                        else:
                            log.error(
                                'ERROR:Unsupported measurement type: {}'
                                    .format(iassay.measurement_type.term))
                        mid_pv = get_pv(
                            assay_to_export['library construction'], 'mid')
                        assay_to_export['poolingstrategy'] = mid_pv
                        seq_instrument = get_pv(
                            assay_to_export['nucleic acid sequencing'],
                            'sequencing instrument')
                        assay_to_export['platform'] = seq_instrument
                        assays_to_export.append(assay_to_export)
            else:
                log.error(
                    'ERROR:Unsupported measurement/technology type {0}/{1}, '
                    'skipping assays'.format(
                        iassay.measurement_type.term,
                        iassay.technology_type.term))

        xexp_set_template = env.get_template('experiment_set.xml')
        xexp_set = xexp_set_template.render(assays_to_export=assays_to_export,
                                            study=istudy,
                                            sra_center_name=sra_center_name,
                                            sra_broker_name=sra_broker_name)
        xrun_set_template = env.get_template('run_set.xml')
        xrun_set = xrun_set_template.render(assays_to_export=assays_to_export,
                                            study=istudy,
                                            sra_center_name=sra_center_name,
                                            sra_broker_name=sra_broker_name)
        samples_to_export = list()
        for assay_to_export in assays_to_export:
            if len([s for s in samples_to_export if
                    s['sample_alias'] == assay_to_export['sample_alias']]) > 0:
                pass
            else:
                samples_to_export.append(assay_to_export)
        xsample_set_template = env.get_template('sample_set.xml')
        xsample_set = xsample_set_template.render(
            assays_to_export=samples_to_export, study=istudy,
            sra_center_name=sra_center_name, sra_broker_name=sra_broker_name)
        log.debug("SRA exporter: writing SRA XML files for study " + study_acc)

        # blitz out whitespaces with etree and format nicely with minidom
        def prettify(xmlstr):
            p = etree.XMLParser(remove_blank_text=True)
            exsub = etree.XML(xmlstr, parser=p)
            x = xml.dom.minidom.parseString(etree.tostring(exsub))
            return x.toprettyxml()

        # validate a doc against one of our SRA schemas
        def validate(docpath, schemaname):
            with open(os.path.join(os.path.dirname(__file__), 'resources',
                                   'sra_schemas', schemaname)) as xsd:
                doc = etree.parse(xsd)
                try:
                    schema = etree.XMLSchema(doc)
                    with open(docpath, 'r') as xsub_file:
                        doc = etree.parse(xsub_file)
                        try:
                            schema.assertValid(doc)
                        except etree.DocumentInvalid as e:
                            log.error(
                                'Schema validation failed on {}'
                                    .format('{0}:\n{1}'.format(
                                    docpath, str(e))))
                except etree.XMLSchemaParseError as e:
                    log.error(e)

        if os.path.exists(export_path):
            with open(os.path.join(
                    export_path, 'submission.xml'), 'w') as xsub_file:
                print(prettify(xsub), file=xsub_file)
            validate(os.path.join(
                export_path, 'submission.xml'), 'SRA.submission.xsd')
            with open(os.path.join(
                    export_path, 'project_set.xml'), 'w') as xproj_set_file:
                print(prettify(xproj), file=xproj_set_file)
            validate(os.path.join(
                export_path, 'project_set.xml'), 'ENA.project.xsd')
            with open(os.path.join(
                    export_path, 'experiment_set.xml'), 'w') as xexp_set_file:
                print(prettify(xexp_set), file=xexp_set_file)
            validate(os.path.join(
                export_path, 'experiment_set.xml'), 'SRA.experiment.xsd')
            with open(os.path.join(
                    export_path, 'run_set.xml'), 'w') as xrun_set_file:
                print(prettify(xrun_set), file=xrun_set_file)
            validate(os.path.join(export_path, 'run_set.xml'), 'SRA.run.xsd')
            with open(os.path.join(
                    export_path, 'sample_set.xml'), 'w') as xsample_set_file:
                print(prettify(xsample_set), file=xsample_set_file)
            validate(os.path.join(
                export_path, 'sample_set.xml'), 'SRA.sample.xsd')
        else:
            raise NotADirectoryError(
                "export path '{}' is not a directory".format(export_path))


def create_datafile_hashes(fileroot, filenames):
    """
    Create md5 file dict for files in a directory with a particular extension

    :param fileroot: Root to directory containing files (assumes all in same dir)
    :param filenames: List of filenames of files to md5, assumed in fileroot
    :return: dict containing filenames and md5s

    Usage:
    >>> filenames = [f for f in listdir('/path/to/my/files') if f.endswith('.fastq.gz')]
    >>> create_datafile_hashes(fileroot='/path/to/my/files', filenames=filesnames)
    { 'myfile1.gz': 'd41d8cd98f00b204e9800998ecf8427e', 'myfile2.gz': 'd41d8cd98f00b204e9800998ecf8427e' }
    """
    def md5sum(filename):
        with open(filename, mode='rb') as f:
            d = hashlib.md5()
            for buf in iter(partial(f.read, 128), b''):
                d.update(buf)
        return d.hexdigest()

    from os.path import isfile, join
    datafilehashes = dict()
    for file in filenames:
        if isfile(join(fileroot, file)):
            datafilehashes[file] = md5sum(filename=join(fileroot, file))
        else:
            raise FileNotFoundError(
                '{} is not a file'.format(join(fileroot, file)))
    return datafilehashes
