########################################################################################################################
#    File: main.py
#  Author: Dan Huckson, https://github.com/unodan
#    Date: 2018-12-22
########################################################################################################################
# This code may need to be updated if the UNECE changes their format of the page in the link below.
# http://www.unece.org/cefact/codesfortrade/codes_index.html
# BeautifulSoup is used to scrap the download page for the current version number of the source zip file.
########################################################################################################################

from os import listdir, remove
from csv import reader
from json import dump
from zipfile import ZipFile
from bs4 import BeautifulSoup
from urllib.request import urlretrieve, urlopen

with urlopen('http://www.unece.org/cefact/codesfortrade/codes_index.html') as response:
    html = response.read()

soup = BeautifulSoup(html, features="html.parser")
parsed_data = soup.find("div", {"id": "c21211"})

version_number = parsed_data.find_all(['td'])[3].text.split()[-1:][0]
unlocode_zip_file = 'loc' + version_number.replace('-', '')[2:] + 'csv.zip'
subdivision_codes_csv_file = version_number + ' SubdivisionCodes.csv'
country_subdivisions = 'country-subdivisions.json'

zones = {}
cities = []
state_codes = []
country_zones = {}
encoding = 'ISO 8859-1'  # Character encoding used by the UNECE for the UN/LOCODE files.

# countries = {'CA': 'Canada', 'US': 'United States', 'AU': 'Australia', 'MX': 'Mexico', 'GB': 'United Kingdom'}
countries = {'CA': 'Canada'}


def get_unlocode_files():
    # Site below is where the UN/LOCODE CSV files are located.
    # http://www.unece.org/cefact/codesfortrade/codes_index.html
    url = 'http://www.unece.org/fileadmin/DAM/cefact/locode/' + unlocode_zip_file
    src_file_name = url.split('/')[-1]
    urlretrieve(url, src_file_name)

    with ZipFile(src_file_name, 'r') as z:
        z.extractall('.')

    remove(src_file_name)

    def get_files():
        file_list = []

        for file_name in listdir('.'):
            if 'UNLOCODE' in file_name and file_name.endswith('.csv'):
                file_list.append(file_name)
        return sorted(file_list)

    return get_files()


unlocode_files = get_unlocode_files()


def get_zone_file(the_zone):

    for file_name in unlocode_files:
        with open(file_name, encoding=encoding) as fn:
            line = fn.readlines()

        last_country_code_in_file = line[-1].split(',')[1].strip('"')

        if the_zone <= last_country_code_in_file:
            return file_name


with open(subdivision_codes_csv_file, encoding=encoding) as f:
    results = reader(f, delimiter=',', quotechar='"')

    for row in results:
        country_code, zone_code, zone_name, zone_type = row
        if zone_type == 'Outlying area':
            continue

        if country_code in countries:
            country_zones[zone_code] = {
                'zone': country_code,
                'code': zone_code,
                'name': zone_name,
                'type': zone_type,
            }

for country_code, country_name in countries.items():

    if country_code not in zones:
        zones[country_code] = {'code': country_code, 'name': country_name, 'zones': {}}

    file = get_zone_file(country_code)
    with open(file, encoding=encoding) as f:
        results = reader(f, delimiter=',', quotechar='"')
        for row in results:
            cntry_code = row[1]
            zone_code = row[5].strip()
            location_name = row[3]
            location_code = row[2]
            location_flags = row[6]
            location_coordinates = row[10]

            if cntry_code == country_code:
                if '4' in location_flags and ' Apt' in location_name:
                    continue

                if zone_code not in country_zones or location_name.startswith('.'):
                    continue

                country = zones.get(cntry_code)

                if zone_code in country['zones']:
                    zone = country['zones'].get(zone_code)
                else:
                    country['zones'][zone_code] = {}
                    zone = country['zones'].get(zone_code)
                    zone['code'] = country_zones[zone_code].get('code')
                    zone['name'] = country_zones[zone_code].get('name')
                    zone['type'] = country_zones[zone_code].get('type')
                    zone['country'] = cntry_code
                    zone['locations'] = {}

                if location_code not in zone['locations']:
                    zone['locations'][location_code] = {
                        'code': location_code,
                        'name': location_name,
                        'flags': location_flags,
                        'coordinates': location_coordinates
                    }

with open(country_subdivisions, 'w', encoding=encoding) as f:
    dump(zones, f, indent=2)