#!/usr/bin/env python3

import json
import urllib.request
from typing import Optional

from bs4 import BeautifulSoup
from praw.models import Submission

from bulkredditdownloader.authenticator import Authenticator
from bulkredditdownloader.errors import NotADownloadableLinkError
from bulkredditdownloader.resource import Resource
from bulkredditdownloader.site_downloaders.gif_delivery_network import GifDeliveryNetwork


class Redgifs(GifDeliveryNetwork):
    def __init__(self, post: Submission):
        super().__init__(post)

    def find_resources(self, authenticator: Optional[Authenticator] = None) -> list[Resource]:
        return super().find_resources(authenticator)

    @staticmethod
    def _get_link(url: str) -> str:
        """Extract direct link to the video from page's source and return it"""
        if '.webm' in url or '.mp4' in url or '.gif' in url:
            return url

        if url[-1:] == '/':
            url = url[:-1]

        url = urllib.request.Request(
            "https://redgifs.com/watch/" + url.split('/')[-1])

        url.add_header(
            'User-Agent',
            'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko)'
            ' Chrome/67.0.3396.87 Safari/537.36 OPR/54.0.2952.64')

        page_source = (urllib.request.urlopen(url).read().decode())

        soup = BeautifulSoup(page_source, "html.parser")
        attributes = {"data-react-helmet": "true", "type": "application/ld+json"}
        content = soup.find("script", attrs=attributes)

        if content is None:
            raise NotADownloadableLinkError("Could not read the page source")

        return json.loads(content.contents[0])["video"]["contentUrl"]