# -----------------------------------------------------------------------------
# Author: Jiawei Liu
# Date: 2024-11-20
# -----------------------------------------------------------------------------
'''
Download script for RMM
Manual review is required to remove some duplicate files.
To run: 
`python RMM\download_script\download.py`
'''

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


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():
    req_session = build_session()

    # Output directory
    output_dir = Path(__file__).parent.parent / "raw"
    output_dir.mkdir(exist_ok=True)

    # Get a list of competition years
    resp = req_session.get("https://rmms.lbi.ro/")
    soup = BeautifulSoup(resp.text, "html.parser")
    a_eles = soup.select_one("#header").find_all("a")[2:]
    urls = [f"{_['href']}/" for _ in a_eles] + [resp.url]

    for url in tqdm(urls):
        year = url.split("/")[-2].replace("rmm", "")
        donwload_urls = []

        # Make request url
        sol_page_url = urljoin(url, "index.php?id=solutions_math")
        prob_page_url = urljoin(url, "index.php?id=problems_math")

        # Make requests
        sol_page_resp = req_session.get(sol_page_url)
        prob_page_resp = req_session.get(prob_page_url)

        sol_page_soup = BeautifulSoup(sol_page_resp.text, "html.parser")
        prob_page_soup = BeautifulSoup(prob_page_resp.text, "html.parser")

        # Check if the page has pdf container
        sol_content_container = sol_page_soup.select_one("#inside_content")
        prob_content_container = prob_page_soup.select_one("#inside_content")
        if sol_content_container is None and prob_content_container is None:
            continue

        sol_a_eles = sol_page_soup.select_one("#inside_content").find_all("a")
        sol_iframe_eles = sol_page_soup.select_one("#inside_content").find_all("iframe")

        # Check if the page has solutions pdf
        if len(sol_iframe_eles) != 0 or len(sol_a_eles) != 0:
            if len(sol_a_eles) != 0:
                donwload_urls = [_["href"] for _ in sol_a_eles]
            elif len(sol_iframe_eles) != 0:
                donwload_urls = [_["src"] for _ in sol_iframe_eles]
        else:
            # Check if the page has problems pdf
            prob_a_eles = prob_page_soup.select_one("#inside_content").find_all("a")
            prob_iframe_eles = prob_page_soup.select_one("#inside_content").find_all("iframe")

            if len(prob_iframe_eles) != 0 or len(prob_a_eles) != 0:
                if len(prob_a_eles) != 0:
                    donwload_urls = [_["href"] for _ in prob_a_eles]
                elif len(prob_iframe_eles) != 0:
                    donwload_urls = [_["src"] for _ in prob_iframe_eles]

        # Download pdf
        for du in donwload_urls:
            if "grading" in du.lower():
                continue

            download_url = urljoin(url, du)

            output_file = output_dir / f"en-{year}-{Path(download_url).name}"
            if output_file.exists():
                continue

            pdf_resp = requests.get(download_url)

            if pdf_resp.status_code != 200:
                print(f"pdf download failed: {download_url}")
                continue

            output_file.write_bytes(pdf_resp.content)


if __name__ == "__main__":
    main()