from re import match
from typing import List, Optional

from scrapthechan.fileinfo import FileInfo
from scrapthechan.parser import Parser

__all__ = ["DvachParser"]


class DvachParser(Parser):
	"""JSON parser for 2ch.hk image board."""

	def __init__(self, board: str, thread: str,
				 skip_posts: Optional[int] = None) -> None:
		super().__init__(board, thread, skip_posts)

	@property
	def json_thread_url(self) -> str:
		return "https://2ch.hk/{board}/res/{thread}.json"

	@property
	def file_base_url(self) -> str:
		return "https://2ch.hk"

	@property
	def subject_field(self) -> str:
		return "subject"

	@property
	def comment_field(self) -> str:
		return "comment"

	@property
	def imageboard(self) -> str:
		return "2ch.hk"

	def _extract_posts_list(self, lst: List) -> List[dict]:
		return lst['threads'][0]['posts']

	def _parse_post(self, post) -> Optional[List[FileInfo]]:
		if not 'files' in post: return None

		files = []

		for f in post['files']:
			if not 'sticker' in f:
				if match(r"^image\.\w+$", f['fullname']) is None:
					fullname = f['fullname']
				else:
					fullname = f['name']
			else:
				fullname = f['name']
			# Here's same thing as 4chan. 2ch.hk also has md5 field, so it is
			# completely fine to hardcode `hash_algo`.
			if 'md5' in f:
				files.append(FileInfo(fullname, f['size'],
							 f"{self.file_base_url}{f['path']}",
							 f['md5'], 'md5'))
			else:
				files.append(FileInfo(fullname, f['size'],
							 f"{self.file_base_url}{f['path']}",
							 None, None))
		return files