# /// script
# requires-python = ">=3.12"
# dependencies = [
#     "datasets",
#     "mediawiki-dump",
#     "mwparserfromhell",
#     "pandas",
#     "requests",
#     "tqdm",
#     "transformers",
#     "dynaword"
# ]
# [tool.uv.sources]
# dynaword = { git = "https://huggingface.co/datasets/danish-foundation-models/danish-dynaword", rev = "00e7f2aee7f7ad2da423419f77ecbb9c0536de0d" }
# ///
import bz2
import datetime
import json
import logging
import os
import re
import subprocess
import sys
import threading

from mediawiki_dump.dumps import IteratorDump
from mediawiki_dump.reader import DumpReaderArticles

from mwparserfromhell import parse

import requests
from tqdm import tqdm
import pandas as pd

from datasets import Dataset
from typing import Tuple

from dynaword.process_dataset import (
    add_token_count,
    ensure_column_order,
    remove_duplicate_text,
    remove_empty_texts,
)

logger = logging.getLogger(__name__)
logging.basicConfig(
    level=logging.INFO, format="%(asctime)s - %(levelname)s - %(message)s"
)
source = "wikisource"


class WtfNodeBridge:
    """
    Persistent Node bridge to wtf_wikipedia.
    Call .parse(wikitext, lang=None) -> (text, is_redirect)
    Remember to call .close() when done.
    """

    def __init__(
        self, node_script_path: str = "parser/wtf_bridge.js", node_cmd: str = "node"
    ):
        self.proc = subprocess.Popen(
            [node_cmd, node_script_path],
            stdin=subprocess.PIPE,
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
            text=True,
            encoding="utf-8",
            bufsize=1,
        )
        self._lock = threading.Lock()

        # background thread to log stderr (helpful for debugging)
        def _drain_stderr(p):
            try:
                for line in p.stderr:
                    logger.warning("wtf_node stderr: %s", line.rstrip())
            except Exception:
                pass

        t = threading.Thread(target=_drain_stderr, args=(self.proc,), daemon=True)
        t.start()

    def parse(self, wikitext: str, lang: str | None = None) -> Tuple[str, bool]:
        if self.proc.poll() is not None:
            raise RuntimeError("Node bridge process has exited")
        payload = {"wikitext": wikitext}
        if lang:
            payload["lang"] = lang
        line = json.dumps(payload, ensure_ascii=False)
        with self._lock:
            # write and flush a single JSON line
            try:
                self.proc.stdin.write(line + "\n")
                self.proc.stdin.flush()
            except BrokenPipeError as e:
                raise RuntimeError("Broken pipe writing to node bridge") from e

            # read exactly one JSON line back
            out_line = self.proc.stdout.readline()
            if not out_line:
                raise RuntimeError("No response from node bridge (it may have exited)")
            res = json.loads(out_line)
            if res.get("error"):
                # choose to either raise or return empty text; here we raise
                raise RuntimeError("Node bridge error: " + res["error"])
            return res.get("text", ""), bool(res.get("isRedirect", False))

    def close(self):
        try:
            if self.proc.stdin:
                self.proc.stdin.close()
        except Exception:
            pass
        try:
            self.proc.terminate()
            self.proc.wait(timeout=3)
        except Exception:
            try:
                self.proc.kill()
            except Exception:
                pass


def download_wiki_dump(url: str, file_path: str):
    """
    Downloads a file from a URL with a progress bar.

    Args:
        url (str): The URL of the file to download.
        file_path (str): The local path to save the file.
    """
    print(f"Downloading {url} to {file_path}...")
    try:
        with requests.get(url, stream=True) as r:
            r.raise_for_status()
            total_size = int(r.headers.get("content-length", 0))
            block_size = 8192  # 8 Kibibytes

            with (
                open(file_path, "wb") as f,
                tqdm(
                    total=total_size, unit="B", unit_scale=True, desc="Downloading"
                ) as pbar,
            ):
                for chunk in r.iter_content(chunk_size=block_size):
                    if chunk:  # filter out keep-alive chunks
                        f.write(chunk)
                        pbar.update(len(chunk))
        logger.info("\nDownload complete.")
    except requests.exceptions.RequestException as e:
        logger.error(f"\nError downloading file: {e}")
        sys.exit(1)


def get_content(file_name: str):
    with bz2.open(file_name, mode="r") as fp:
        yield from fp


def process_dump_to_parquet(bz2_file_path: str, parquet_file_path: str):
    dump = IteratorDump(iterator=get_content(file_name=bz2_file_path))
    pages = DumpReaderArticles().read(dump)
    articles = []
    today = datetime.datetime.now().strftime("%Y-%m-%d")

    bridge = WtfNodeBridge("parser/wtf_bridge.js")
    try:
        for page in tqdm(pages):
            try:
                plain_text, is_redirect = bridge.parse(page.content, lang="da")
            except Exception as exc:
                logger.warning(
                    "wtf parse failed for page %s: %s -- falling back to mwparserfromhell",
                    getattr(page, "title", "<unknown>"),
                    exc,
                )
                plain_text = parse(page.content).strip_code().strip()
                is_redirect = plain_text.startswith("REDIRECT")

            if is_redirect:
                continue

            # Additional cleanup if you like (wtf.text() already removes a lot)
            plain_text = re.sub(
                r"thumb(?:\|(?:left|right|center|\d+px)*)*\|[^\n]*", "", plain_text
            ).strip()

            if len(plain_text) == 0:
                logger.warning("Skipping empty article")
                continue

            date = datetime.datetime.strptime(
                page.timestamp, "%Y-%m-%dT%H:%M:%SZ"
            ).strftime("%Y-%m-%d")

            articles.append(
                {
                    "id": f"{source}_{page.page_id}",
                    "source": source,
                    "created": f"{date}, {date}",
                    "text": f"{page.title}\n{plain_text}",
                    "added": today,
                }
            )
    finally:
        bridge.close()

    df = pd.DataFrame(articles)
    ds = Dataset.from_pandas(df)
    ds = add_token_count(ds)
    ds = remove_empty_texts(ds)
    ds = remove_duplicate_text(ds)
    ds = ensure_column_order(ds)
    ds.to_parquet(parquet_file_path, compression="snappy")


def main():
    """
    Main function to orchestrate the download and processing.
    """
    # --- Configuration ---
    # URL for the latest Danish Wikipedia articles dump
    WIKI_DUMP_URL = f"https://dumps.wikimedia.org/da{source}/latest/da{source}-latest-pages-articles.xml.bz2"

    # Local file paths
    DOWNLOADED_BZ2_FILE = f"tmp/da{source}-latest-pages-articles.xml.bz2"
    OUTPUT_PARQUET_FILE = f"{source}.parquet"

    # --- Execution ---
    # 1. Download the dump file
    if not os.path.exists(DOWNLOADED_BZ2_FILE):
        download_wiki_dump(WIKI_DUMP_URL, DOWNLOADED_BZ2_FILE)
    else:
        print(f"File '{DOWNLOADED_BZ2_FILE}' already exists. Skipping download.")

    # 2. Process the dump and save to Parquet
    process_dump_to_parquet(DOWNLOADED_BZ2_FILE, OUTPUT_PARQUET_FILE)

    # 3. (Optional) Clean up the downloaded file
    # If you want to keep the bz2 file, comment out the next line.
    print(f"Cleaning up by removing '{DOWNLOADED_BZ2_FILE}'...")
    os.remove(DOWNLOADED_BZ2_FILE)

    print("\nScript finished successfully.")


if __name__ == "__main__":
    # Before running, make sure you have the required libraries installed:
    # pip install requests mwparserfromhell pandas pyarrow
    main()