"""Metadata transformation module."""

from datetime import datetime, timezone

import constants


def transform_metadata(sound_recording_metadata):
    """Transform release metadata from graphQL into ddex ern srr facebook formatted metadata."""
    sound_recording_metadata = find_canonical_sound_recordings(sound_recording_metadata)
    current_datetime = datetime.now(timezone.utc)
    transformed_metadata = {}
    # Message Header Metadata
    transformed_metadata['message_thread_id'] = sound_recording_metadata.get('isrc')
    transformed_metadata['message_id'] = build_message_id(sound_recording_metadata.get('isrc'), current_datetime)
    transformed_metadata['message_created_date_time'] = current_datetime.strftime(
        '%Y-%m-%dT%H:%M:%SZ')  # iosformat with Zulu
    # Resource List Metadata
    transformed_metadata['isrc'] = sound_recording_metadata.get('isrc')
    transformed_metadata['resource_reference'] = 'A1'
    transformed_metadata['title_text'] = sound_recording_metadata.get('trackName')
    transformed_metadata['meta_language_code'] = sound_recording_metadata.get('metaLanguageCode')
    transformed_metadata['language_of_performance'] = build_language_of_performance(
        sound_recording_metadata)
    transformed_metadata['duration'] = 'PT{}M{}S'.format(
        sound_recording_metadata.get('durationMinutes'),
        sound_recording_metadata.get('durationSeconds'))
    # Sound Recording Details By Territory Metadata
    transformed_metadata['display_title'] = build_display_title(
        sound_recording_metadata.get('trackName'),
        sound_recording_metadata.get('version'))
    transformed_metadata['formal_title'] = sound_recording_metadata.get('trackName')
    transformed_metadata['sub_title'] = sound_recording_metadata.get('version')
    transformed_metadata['display_artists'] = build_display_artists(
        sound_recording_metadata.get('primaryArtists'),
        sound_recording_metadata.get('writers'))
    transformed_metadata['label'] = sound_recording_metadata.get('label')
    transformed_metadata['pline_year'] = build_pline_year(sound_recording_metadata.get('pInfo'))
    transformed_metadata['pline_text'] = sound_recording_metadata.get('pInfo')
    transformed_metadata['parental_warning_type'] = build_parental_warning_type(
        sound_recording_metadata.get('explicit'))
    return transformed_metadata


def find_canonical_sound_recordings(sound_recording_metadata):
    """Return only track data from in-content, digital audio tracks."""
    canoncial_tuid = None
    canonical_track_data = None
    for tuid, track_data in sound_recording_metadata.items():
        product = track_data['product']
        if (product['productConfiguration'] == 'Digital Audio'
        and product['status'] == 'in_content'  # noqa: W503
        and product['deletions'] == 'N'):  # noqa: W503
            if canoncial_tuid is None or tuid < canoncial_tuid:
                canoncial_tuid = tuid
                canonical_track_data = track_data
    return canonical_track_data


def build_message_id(sound_recording_id, current_datetime):
    """Build ddex ern srr facebook formatted message_id element."""
    release_created_datetime = current_datetime.strftime('%Y%m%d_%H%M%SZ')
    return f'{sound_recording_id}_{release_created_datetime}'


def build_parental_warning_type(explicit_flag):
    """Build ddex ern srr facebook formatted parental_warning_type element."""
    parental_warning_type = 'NotExplicit'
    if explicit_flag == 'Y':
        parental_warning_type = 'Explicit'
    elif explicit_flag == 'C':
        parental_warning_type = 'ExplicitContentEdited'
    return parental_warning_type


def build_display_title(track_name, version):
    """Build ddex ern srr facebook formatted display_title element."""
    display_title = track_name
    if version:
        display_title = track_name + ' ({})'.format(version)
    return display_title


def build_display_artists(primary_artists, writers):
    """Build ddex ern srr facebook formatted display_artist list."""
    display_artists = []
    for artist in primary_artists:
        transformed_artist = {}
        if artist['artistType'] not in constants.DISPLAY_ARTIST_TYPES:
            continue
        elif artist['artistType'] == 'performer':
            transformed_artist['artistRole'] = 'MainArtist'
        elif artist['artistType'] == 'featuring':
            transformed_artist['artistRole'] = 'FeaturedArtist'
        elif artist['artistType'] == 'producer':
            transformed_artist['artistRole'] = 'Producer'
        elif artist['artistType'] == 'remixer':
            transformed_artist['artistRole'] = 'Remixer'
        transformed_artist['fullName'] = artist['artistName']
        display_artists.append(transformed_artist)
    for writer in writers:
        transformed_writer = {}
        transformed_writer['fullName'] = writer['trackWriterName']
        transformed_writer['artistRole'] = 'Composer'
        display_artists.append(transformed_writer)
    return display_artists


def build_language_of_performance(sound_recording_metadata):
    """Build ddex ern srr facebook formatted language_of_performance."""
    language_of_performance = sound_recording_metadata.get('language').get('iso_639_1_code')
    if language_of_performance:
        language_of_performance = language_of_performance.lower()
    return language_of_performance


def build_pline_year(pline):
    """Extrat 4 digit year from start of the pline. Raise error if year is invalid."""
    pline_year = pline[0:4]
    if not pline_year.isnumeric() or len(pline_year) < 4:
        raise Exception("pline '{}' has invalid year".format(pline))
    return pline_year