legex/extract_raw_text.py

"""Extract full text from goldenset PDFs in data/raw/drive-download-*/<Country>/.

Writes data/<cc>/full_text.jsonl with fields: case_id, full_text.
Text is whitespace-normalized (no newlines, runs of whitespace collapsed to one space).

Usage:
    uv run python -m legex.extract_raw_text
    uv run python -m legex.extract_raw_text --country kr
"""

from __future__ import annotations

import argparse
import json
import logging
import re
import sys
from pathlib import Path

from pypdf import PdfReader

log = logging.getLogger("legex.extract_raw_text")

REPO_ROOT = Path(__file__).resolve().parent.parent
RAW_DIR = REPO_ROOT / "data" / "raw"
DATA_DIR = REPO_ROOT / "data"

FOLDER_TO_CC: dict[str, str] = {
    "Armenia": "am",
    "Belgium": "be",
    "China": "cn",
    "Dominican_Republic": "do",
    "Georgia": "ge",
    "Hong_Kong": "hk",
    "India": "in",
    "Nepal": "np",
    "New_Zealand": "nz",
    "Philippines": "ph",
    "Russia": "ru",
    "Singapore": "sg",
    "South_Korea fixed": "kr",
    "South_Korea": "kr",
    "Spain": "es",
    "Taiwan": "tw",
    "Ukraine": "ua",
    "United_States": "us",
}


_WS_RE = re.compile(r"\s+")


def normalize_ws(text: str) -> str:
    return _WS_RE.sub(" ", text).strip()


def extract_pdf_text(pdf: Path) -> str:
    try:
        reader = PdfReader(str(pdf))
        text = " ".join((page.extract_text() or "") for page in reader.pages)
    except Exception as e:
        log.warning(f"failed to read {pdf}: {type(e).__name__}: {e}")
        return ""
    return normalize_ws(text)


def find_country_folders() -> dict[str, list[Path]]:
    """Map country code -> list of PDFs found across all drive-download-* folders."""
    by_cc: dict[str, list[Path]] = {}
    unknown: list[str] = []
    for drive_dir in sorted(RAW_DIR.glob("drive-download-*")):
        if not drive_dir.is_dir():
            continue
        for sub in sorted(drive_dir.iterdir()):
            if not sub.is_dir():
                continue
            cc = FOLDER_TO_CC.get(sub.name)
            if cc is None:
                unknown.append(str(sub))
                continue
            pdfs = sorted(sub.glob("*.pdf"))
            by_cc.setdefault(cc, []).extend(pdfs)
    if unknown:
        log.warning("unmapped folders (skipped): %s", ", ".join(unknown))
    return by_cc


def write_jsonl(cc: str, pdfs: list[Path]) -> Path:
    out_dir = DATA_DIR / cc
    out_dir.mkdir(parents=True, exist_ok=True)
    out_path = out_dir / "full_text.jsonl"
    with out_path.open("w", encoding="utf-8") as f:
        for pdf in pdfs:
            text = extract_pdf_text(pdf)
            f.write(json.dumps({"case_id": pdf.stem, "full_text": text}, ensure_ascii=False))
            f.write("\n")
    return out_path


def main() -> int:
    logging.basicConfig(level=logging.INFO, format="%(levelname)s %(name)s: %(message)s")
    ap = argparse.ArgumentParser(description=__doc__)
    ap.add_argument(
        "--country",
        "-c",
        action="append",
        help="Only process the given country code (repeatable). Default: all.",
    )
    args = ap.parse_args()

    if not RAW_DIR.exists():
        log.error("raw dir not found: %s", RAW_DIR)
        return 1

    by_cc = find_country_folders()
    if args.country:
        wanted = {c.lower() for c in args.country}
        by_cc = {cc: pdfs for cc, pdfs in by_cc.items() if cc in wanted}
        missing = wanted - set(by_cc)
        if missing:
            log.error("no PDFs found for: %s", ", ".join(sorted(missing)))
            return 1

    if not by_cc:
        log.error("no country folders matched")
        return 1

    for cc in sorted(by_cc):
        pdfs = by_cc[cc]
        log.info("[%s] extracting %d PDFs", cc, len(pdfs))
        out = write_jsonl(cc, pdfs)
        log.info("[%s] wrote %s", cc, out)
    return 0


if __name__ == "__main__":
    sys.exit(main())