from dataclasses import dataclass
from decimal import Decimal
from functools import reduce
from pyquery import PyQuery as pq
import json
import re
import os
import requests
import subprocess
import logging
from supermarktconnector.ah import AHConnector
from typing import List


vat = Decimal('1.09')


@dataclass
class Product:
    name: str
    price: Decimal
    gtin: str
    units: int
    aliases: List[str]

    def __str__(self):
        return self.name


_ah = None

def ah_get_by_gtin(gtin13):
    assert re.match(r'^\d{13}$', gtin13)

    global _ah
    if not _ah:
        _ah = AHConnector()

    ah_prod = _ah.get_product_by_barcode(gtin13)

    units_description = ah_prod['salesUnitSize']
    units = 1
    if (m := re.search(r'^(\d+)', units_description)):
        units = int(m[1])

    return Product(
        name=ah_prod['title'],
        price=Decimal(ah_prod['priceBeforeBonus']),
        gtin=gtin13,
        units=units,
        aliases=[],
    )


_sess = requests.Session()

def sligro_client():
    global _sess

    if _sess.cookies:
        return _sess

    username = os.getenv('SLIGRO_USERNAME')
    password = os.getenv('SLIGRO_PASSWORD')
    if not username:
        raise Exception('missing SLIGRO_USERNAME')
    if not password:
        raise Exception('missing SLIGRO_PASSWORD')

    resp = _sess.post('https://www.sligro.nl/api/user/sligro-nl/nl/login',
                      json={'username': username, 'password': password, 'rememberMe': False})
    resp.raise_for_status()
    logging.info('Sligro login ok!')

    return _sess


def sligro_get_by_gtin(gtin13):
    assert re.match(r'^\d{13}$', gtin13)
    gtin14 = f'{gtin13:0>14}'

    # The search feature of the website returns results in JSON and handles GTIN formats. Neat!
    # However, it can be a bit picky about leading zeros, so we try to query with GTIN14 as that is
    # what works in the most cases. Sometimes GTIN13 is still required though
    for gtin_whatever in [gtin14, gtin13]:
        response = requests.get(f'https://www.sligro.nl/api/product-overview/sligro-nl/nl/query/3?term={gtin_whatever}')
        response.raise_for_status()
        body = response.json()
        if 'products' in body:
            break
    else:
        raise Exception(f'sligro: {gtin13} not found')

    product = body['products'][0]
    sku = product["code"]

    # Query the product page itself, there is more info that we need on there. The 'url' field in
    # the product object gives a 404, but the actual product page URL can be created from the search
    # results.
    url_slug = '-'.join([product['brandName'], product['name'], product['contentDescription']])\
        .replace(' ', '-')\
        .replace('\'', '-')\
        .replace('&', '-')\
        .replace(',', '')\
        .replace('%', '')\
        .lower()
    prod_resp = requests.get(f'https://www.sligro.nl/p.{sku}.html/{url_slug}.html')
    prod_resp.raise_for_status()

    product_page = pq(prod_resp.text)
    prod_ext_data_script = product_page('script[data-hypernova-key="ProductDetail"]')
    prod_ext_data = json.loads(prod_ext_data_script[0].text.replace('<!--', '').replace('-->', ''))

    # Most products contain products which have distinct barcodes.
    sub_gtin = prod_ext_data['propsData']['data'].get('gtinUnderlyingUnit', None)
    if sub_gtin:
        sub_gtin = sub_gtin.lstrip('0')

    # The contentDescription field holds the number of individual packages per box sold.
    units, volume = parse_content_description(product['contentDescription'])

    # Pricing requires logging in and is on a separate endpoint...
    pricing_resp = sligro_client().get(f'https://www.sligro.nl/api/cart/sligro-nl/customerorganizationdatas?productCodes={sku}')
    pricing = pricing_resp.json()['data']['products'][0]

    # If fromPrice is present, this product has a temporary discount. We prefer the regular price as
    # we do not want to make a loss on stock that was purchased earlier.
    if (from_price := pricing.get('fromPrice')):
        price_obj = from_price
    else:
        price_obj = pricing['price']

    return Product(
        name=f'{product["brandName"]} {product["name"]} ({volume})',
        price=Decimal(price_obj['value']) * vat,
        gtin=gtin13,
        units=units,
        aliases=[sub_gtin] if sub_gtin else [],
    )


# The contentDescription seems to have a formatting consistent enough for regex matching. Some
# products have multiple levels of packaging, but the last or only component is always the
# volume or weight.
def parse_content_description(cd):
    # These ones are weird.
    if cd.endswith(' rollen'):
        return int(cd.split(' ')[0]), 'rol'
    if (m := re.search(r'^Pak (\d+) stuks$', cd)):
        return int(m[1]), ''
    if (m := re.search(r'^(\d+) Flessen (\d+ CL)$', cd)):
        return int(m[1]), m[2]

    groups = re.split(r'\s+x\s+', cd)
    volume = groups[-1]
    unit_groups = groups[:-1]

    sub_units = (int(re.search(r'(\d+)', g)[0]) for g in unit_groups)
    units = reduce(lambda a, b: a * b, sub_units, 1)

    return units, volume