"""Here are defined the JSON parsers for imageboards."""
from re import search
from typing import List, Optional

from scrapthechan.parser import Parser


__all__ = ["SUPPORTED_IMAGEBOARDS", "get_parser_by_url", "get_parser_by_site"]


URLRX = r"https?:\/\/(?P<s>[\w\.]+)\/(?P<b>\w+)\/(?:\w+)?\/(?P<t>\w+)"
SUPPORTED_IMAGEBOARDS: List[str] = ["4chan.org", "lainchan.org", "2ch.hk", \
	"8kun.top"]


def get_parser_by_url(url: str, skip_posts: Optional[int] = None) -> Parser:
	"""Parses URL and extracts from it site name, board and thread.
	And then returns initialised Parser object for detected imageboard."""
	site, board, thread = search(URLRX, url).groups()
	return get_parser_by_site(site, board, thread, skip_posts)

def get_parser_by_site(site: str, board: str, thread: str,
					   skip_posts: Optional[int] = None) -> Parser:
	"""Returns an initialised parser for `site` with `board` and `thread`."""
	if '4chan' in site:
		from .fourchan import FourChanParser
		return FourChanParser(board, thread, skip_posts)
	elif 'lainchan' in site:
		from .lainchan import LainchanParser
		return LainchanParser(board, thread, skip_posts)
	elif '2ch' in site:
		from .dvach import DvachParser
		return DvachParser(board, thread, skip_posts)
	elif '8kun' in site:
		from .eightkun import EightKunParser
		return EightKunParser(board, thread, skip_posts)
	else:
		raise NotImplementedError(f"Parser for {site} is not implemented")