# ILIAS

import aiohttp
import asyncio
import bs4
import logging
import pathlib
import re

from .organizer import Organizer
from .ilias_authenticators import ShibbolethAuthenticator
from . import utils

__all__ = [
	"ILIAS",
]
logger = logging.getLogger(__name__)

class ILIAS:
	FILE_RE = re.compile(r"goto\.php\?target=(file_\d+_download)")
	DIR_RE = re.compile(r"ilias\.php\?ref_id=(\d+)")

	def __init__(self, base_path, cookie_file):
		self.base_path = base_path

		self._auth = ShibbolethAuthenticator(base_path / cookie_file)

	async def synchronize(self, ref_id, to_dir, transform=lambda x: x, filter=lambda x: True):
		logging.info(f"Synchronizing {ref_id} to {to_dir} using the ILIAS synchronizer.")

		sync_path = pathlib.Path(self.base_path, to_dir)
		orga = Organizer(self.base_path, sync_path)

		orga.clean_temp_dir()

		files = await self._crawl(pathlib.PurePath(), f"fold_{ref_id}", filter)
		await self._download(orga, files, transform)

		orga.clean_sync_dir()
		orga.clean_temp_dir()

	async def close(self):
		await self._auth.close()

	async def _crawl(self, dir_path, dir_id, filter_):
		soup = await self._auth.get_webpage(dir_id)

		found_files = []

		files = self._find_files(soup)
		for (name, file_id) in files:
			path = dir_path / name
			found_files.append((path, file_id))
			logger.debug(f"Found file {path}")

		dirs = self._find_dirs(soup)
		for (name, ref_id) in dirs:
			path = dir_path / name
			logger.debug(f"Found dir {path}")
			if filter_(path):
				logger.info(f"Searching {path}")
				files = await self._crawl(path, ref_id, filter_)
				found_files.extend(files)
			else:
				logger.info(f"Not searching {path}")

		return found_files

	async def _download(self, orga, files, transform):
		for (path, file_id) in files:
			to_path = transform(path)
			if to_path is not None:
				temp_path = orga.temp_file()
				await self._auth.download_file(file_id, temp_path)
				orga.add_file(temp_path, to_path)

	def _find_files(self, soup):
		files = []

		found = soup.find_all("a", {"class": "il_ContainerItemTitle", "href": self.FILE_RE})
		for element in found:
			file_stem = element.string
			file_id = re.search(self.FILE_RE, element.get("href")).group(1)

			# find out file type
			file_type = element.parent.parent.parent.find("div", {"class": "il_ItemProperties"}).find("span").string.strip()

			file_name = f"{file_stem}.{file_type}"
			files.append((file_name, file_id))

		return files

	def _find_dirs(self, soup):
		dirs = []

		found = soup.find_all("a", {"class": "il_ContainerItemTitle", "href": self.DIR_RE})
		for element in found:
			dir_name = element.string
			ref_id = re.search(self.DIR_RE, element.get("href")).group(1)
			dir_id = f"fold_{ref_id}"
			dirs.append((dir_name, dir_id))

		return dirs