import json
import os
import sys


BEFORE_FILENAME = os.environ.get('BEFORE_FILENAME', '')
AFTER_FILENAME = os.environ.get('AFTER_FILENAME', '')

AMAZON_TERRITORIES = [
    'US',
    'FR',
    'GB',
    'DE',
    'AT',
    'CH',
    'JP',
    'IT',
    'ES',
    'IE'
]


def get_results(filename):
    path = os.path.dirname(os.path.realpath(__file__)) + \
        '/data/' + filename

    with open(path, 'r') as input_file:
        return json.load(input_file)


def find_matching_result(results, product_id, pricing_family_id):
    for result in results:
        if result['product_id'] == product_id and \
                result['pricing_family_id'] == pricing_family_id:
            return result
    return None


def group_album_items(items):
    grouped = {}
    for item in items:
        if item['price_code'] not in grouped:
            grouped[item['price_code']] = {
                'price_code': item['price_code'],
                'territories': item['territories']
            }
        else:
            grouped[item['price_code']]['territories'] += item['territories']

    result = grouped.values()

    for item in result:
        territories = []
        for territory in item['territories']:
            if territory in AMAZON_TERRITORIES:
                territories.append(territory)

        item['territories'] = territories
        item['territories'].sort()

    return result


def find_matching_album_item(items, before_item):
    for item in items:
        if item['territories'] == before_item['territories'] and \
                item['price_code'] == before_item['price_code']:
            return item
    return None


def diff_album_items(before_items, after_items):
    grouped_before_items = group_album_items(before_items)
    grouped_after_items = group_album_items(after_items)

    for before_item in grouped_before_items:
        if len(before_item['territories']) == 0:
            continue

        after_item = find_matching_album_item(grouped_after_items, before_item)

        if not after_item:
            return False

    return True


def group_track_items(items):
    grouped = {}
    for item in items:
        for track_id in item['track_ids']:
            key = '{0}-{1}'.format(track_id, item['price_code'])

            if key not in grouped:
                grouped[key] = {
                    'track_id': track_id,
                    'price_code': item['price_code'],
                    'territories': item['territories']
                }
            else:
                grouped[key]['territories'] += item['territories']

    result = grouped.values()

    for item in result:
        territories = []
        for territory in item['territories']:
            if territory in AMAZON_TERRITORIES:
                territories.append(territory)

        item['territories'] = territories
        item['territories'].sort()

    return result


def find_matching_track_item(items, before_item):
    for item in items:
        if item['territories'] == before_item['territories'] and \
                item['price_code'] == before_item['price_code'] and \
                item['track_id'] == before_item['track_id']:
            return item
    return None


def diff_track_items(before_items, after_items):
    grouped_before_items = group_track_items(before_items)
    grouped_after_items = group_track_items(after_items)

    for before_item in grouped_before_items:
        if len(before_item['territories']) == 0:
            continue

        after_item = find_matching_track_item(grouped_after_items, before_item)

        if not after_item:
            return False

    return True


try:
    print('About to get before results from {0}'.format(BEFORE_FILENAME))

    before_results = get_results(BEFORE_FILENAME)

    print('Got {0} before results'.format(len(before_results)))
    print('About to get after results from {0}'.format(AFTER_FILENAME))

    after_results = get_results(AFTER_FILENAME)

    print('Got {0} after results'.format(len(after_results)))

    successes = []
    failures = []
    not_found = []
    for before_result in before_results:
        product_id = before_result['product_id']
        pricing_family_id = before_result['pricing_family_id']

        print('About to find match for product {0} and pricing family {1}'.\
            format(product_id, pricing_family_id))

        after_result = find_matching_result(
            after_results, product_id, pricing_family_id)

        if not after_result:
            print('No matching result found')
            not_found.append([product_id, pricing_family_id])
            continue

        print('Found matching result')
        print('About to diff results')

        if pricing_family_id == 2:
            success = diff_album_items(
                before_result['items'], after_result['items'])
        else:
            success = diff_track_items(
            before_result['items'], after_result['items'])

        if success:
            print('Diff successfull')
            successes.append([product_id, pricing_family_id])
        else:
            print('Diff failed')
            failures.append([product_id, pricing_family_id])

    print('Done diffing results')
    print('{0} successes. {1} failures. {2} not found.'.format(
        len(successes), len(failures), len(not_found)))

    if len(failures) > 0:
        print('Failures:')
        print(failures)

    sys.exit()
except Exception as e:
    sys.exit(e)