#!/usr/bin/env python3

from urllib import request
import gzip
import re

host = 'https://adventofcode.com/'
sol_path = '{year}/day/{day}'
input_path = sol_path + '/input'

sol_pattern = re.compile(r'Your puzzle answer was <code>(.*?)</code>')
user_pattern = re.compile(r'<div class="user">(.*?)</div>')


class BadRequest(Exception):
    pass

class AdventSession(object):
    def __init__(self, session_key):
        head = 'session='
        if session_key.startswith(head):
            session = session_key
        else:
            session = head + session_key
        self.headers = {'Cookie' : session,
                        'Accept-Encoding' : 'gzip'}

    def get(self, url):
        req = request.Request(url, headers=self.headers)
        res = request.urlopen(req)
        text = gzip.decompress(res.read()).decode('utf-8')
        if res.status != 200:
            raise BadRequest(text)
        return text

    def get_user(self):
        text = self.get(host) 
        return user_pattern.search(text).group(1)

    def get_input(self, year, day):
        text = self.get(host + input_path.format(year=year, day=day))
        return text

    def get_solutions(self, year, day):
        text = self.get(host + sol_path.format(year=year, day=day))
        return sol_pattern.findall(text)