from bs4 import BeautifulSoup
import requests
import re
from urllib.parse import urlunsplit
from multiprocessing.dummy import Pool as ThreadPool


DOMAIN = "4kwallpapers.com"


class PageHandler:
    def __init__(self, domain, path):
        self.domain = domain
        self.path = path

    @property
    def url(self):
        return urlunsplit(("https", self.domain, self.path, "", ""))

    def get(self, path="", query="", soup=True):
        r = requests.get(self.relative_url(path, query))

        if r.status_code != 200:
            raise requests.exceptions.RequestException()

        if soup:
            return BeautifulSoup(r.content, "html.parser")

        return r

    def relative_url(self, path="", query=""):
        return urlunsplit(("https", self.domain, "/".join((self.path,
                                                        path.strip("/"))),
                          query, ""))


class Scraper(PageHandler):
    def __init__(self, domain=DOMAIN):
        super().__init__(domain, "")

        self._categories = None

    @property
    def categories(self):
        if not self._categories:
            # Get them if not cached
            soup = self.get(soup=True)
            ul = soup.find("ul", class_="cats")
            cats = []

            for li in ul.findAll("li"):
                anchor = li.find("a")

                cats.append(Category(anchor.get_text(), self.domain,
                                     anchor["href"].strip("/")))

            self._categories = cats

        return self._categories

    @property
    def images(self):
        return sum([cat.images for cat in self.categories], [])


class Category(PageHandler):
    def __init__(self, name, domain, path):
        super().__init__(domain, path)

        self.name = name
        self._images = None

    @property
    def images(self):
        if not self._images:
            # Get base page
            soup = self.get()

            # Get how many pages there are
            pages_p = soup.find("p", class_="pages")

            count = 1

            # The paragraph doesn't exist if there's only one page
            if pages_p:
                anchors = pages_p.findAll("a")
                count = max([int(res.group(1))
                              for anchor in anchors
                              if (res := re.match("\?page=([0-9]+)",
                                                  anchor["href"]))]
                )

            # Now, we get the URL for every wallpaper's page
            pages = [self.relative_url(query="page={}".format(i))
                     for i in range(1, count + 1)]

            self._images = []
            for i in range(1, count + 1):
                soup = self.get(query="page={}".format(i))

                pics_list = soup.find("div", id="pics-list")
                self._images.extend(
                    [Image(self.domain, anchor["href"])
                     for anchor in pics_list.findAll("a",class_="wallpapers__canvas_image")])

        return self._images


class Image(PageHandler):
    def __init__(self, domain, path):
        super().__init__(domain, path)

        self._image_url = None
        self._original_image_url = None

    def _get_urls(self):
        soup = self.get()

        self._image_url = soup.find("a", id="resolution")["href"]
        self._original_image_url = soup.find("a", class_="original")["href"]

    @property
    def image_url(self):
        if not self._image_url:
            self._get_urls()

        return self._image_url

    @property
    def original_image_url(self):
        if not self._original_image_url:
            self._get_urls()

        return self._original_image_url