import json
import re

from urllib.parse import urlparse, parse_qs

from requests_futures.sessions import FuturesSession


BASE_URL = 'https://teespring.com'
CAMPAIGN_DATA = re.compile(r'var campaign_data = (\{.*\})</script>')


class Teespring(object):
    def __init__(self, store_name):
        self.store_name = store_name

    def _parse_variants(self, pid, campaign_data):
        result = []
        product = campaign_data['products'][pid]
        for color in product['colors']:
            cid = str(color['id'])
            front = [i for i in product['images'][cid] if i['side'] == 'front']
            back = [i for i in product['images'][cid] if i['side'] == 'back']
            result.append(dict(
                color_id=cid,
                front_url=front[0]['src'],
                back_url=back[0]['src'],
                color_value=color['value']))
        return result

    def fetch_products(self):
        session = FuturesSession()
        def get_products(page):
            url = '{0}/api/stores/{1}/store_products'.format(BASE_URL, self.store_name)
            params = dict(page=page)
            return session.get(url, params=params, headers={'Accept': 'application/json'})
        result = []
        requests = []
        page = 1
        while True:
            request = get_products(page)
            r = request.result()
            if not r.ok:
                return []
            data = r.json()
            for product in data.get('products', []):
                product['url'] = BASE_URL + product['url']
                requests.append(session.get(product['url']))
                result.append(product)
            next_url = data.get('next')
            if not next_url:
                break
            q = parse_qs(urlparse(next_url).query)
            page = q.get('page', [])[0]
        for product, request in zip(result, requests):
            q = parse_qs(urlparse(product['url']).query)
            pid = q.get('pid', [])[0]
            r = request.result()
            m = CAMPAIGN_DATA.search(r.text)
            if m:
                campaign_data = json.loads(m.group(1))
                product['variants'] = self._parse_variants(pid, campaign_data)
        return result