# -----------------------------------------------------------------------------
# Author: Jiawei Liu
# Date: 2024-11-21
# -----------------------------------------------------------------------------
'''
Download script for Dutch TST
To run: 
`python Dutch_TST/download_script/download.py`
'''

import requests
from bs4 import BeautifulSoup
from tqdm import tqdm
from pathlib import Path
from requests.adapters import HTTPAdapter
from urllib3.util.retry import Retry
from urllib.parse import urljoin


def build_session(
    max_retries: int = 3,
    backoff_factor: int = 2,
    session: requests.Session = None
) -> requests.Session:
    """
    Build a requests session with retries

    Args:
        max_retries (int, optional): Number of retries. Defaults to 3.
        backoff_factor (int, optional): Backoff factor. Defaults to 2.
        session (requests.Session, optional): Session object. Defaults to None.
    """
    session = session or requests.Session()
    adapter = HTTPAdapter(max_retries=Retry(total=max_retries, backoff_factor=backoff_factor))
    session.mount("http://", adapter)
    session.mount("https://", adapter)
    session.headers.update({
        "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.3"
    })

    return session


def main():
    base_url = "https://www.wiskundeolympiade.nl/wedstrijdarchief/teamselectie"
    req_session = build_session()

    output_dir = Path(__file__).parent.parent / "raw"
    output_dir.mkdir(parents=True, exist_ok=True)

    resp = req_session.get(base_url)

    if resp.status_code != 200:
        raise Exception(f"Failed to retrieve the page. Status code: {resp.status_code}")

    soup = BeautifulSoup(resp.text, 'html.parser')
    pdf_link_eles = soup.find_all('a', href=lambda t: '.pdf' in t and 'uitwerkingen' in t.lower() if t else False)
    pdf_link_eles.extend(
        soup.find_all(
            'a',
            href=lambda t: \
                '.pdf' in t and 'opgaven' in t.lower() and 'uitwerkingen' not in t.lower() and any([y in t for y in ["2007", "2008"]])
                if t else False
        )
    )

    for pdf_link_ele in tqdm(pdf_link_eles):
        pdf_link = pdf_link_ele['href']
        year = pdf_link.split('/')[-2]

        output_file = output_dir / f"nl-{year}-{Path(pdf_link).name}"

        # Check if the file already exists
        if output_file.exists():
            continue

        pdf_resp = req_session.get(urljoin(base_url, pdf_link))

        if pdf_resp.status_code != 200:
            print(f"Failed to download {pdf_link}")
            continue

        output_file.write_bytes(pdf_resp.content)


if __name__ == "__main__":
    main()