APMO/segment_script/segment.py

import os
import re
import json

from tqdm import tqdm
from loguru import logger

from pathlib import Path
from typing import Tuple, List


problem_tag = 'Problem'
solution_tag = 'Solution'


def analyze(text: str) -> Tuple[List, int]:
    """
    Analyze the text and return the tags and problem number.

    Args:
        text (str): The markdown text to analyze.

    Returns:
        Tuple[List, int]: A tuple containing the tags and problem number.
    """
    problem_pattern = re.compile(r'(?:\n|# )(?:Problem|Question)\s+(\d+)(.)?', re.IGNORECASE)
    solution_pattern = re.compile(r'(?:\n|# |\()(?:Solution|FIRST SOLUTION|SECOND SOLUTION|THIRD SOLUTION|Solution and Marking Scheme|First Solution and Marking Scheme|Second Solution and Marking Scheme)(?:\s+(\d*)|\)|\.|\n|:|\s+\(.+\)(:|.))', re.IGNORECASE)

    tags = []
    tags.extend([(x, problem_tag) for x in problem_pattern.finditer(text)])
    problem_num = len(tags)

    tags.extend([(x, solution_tag) for x in solution_pattern.finditer(text)])
    tags.sort(key=lambda x: x[0].start())
    return tags, problem_num


def segment(text: str, tags):
    starts = []
    ends = []

    for i in range(len(tags)):
        starts.append(tags[i][0].end())
        if i + 1 < len(tags):
            ends.append(tags[i + 1][0].start())
        else:
            ends.append(len(text))

    return [text[start:end].strip().strip('#').strip() for start, end in zip(starts, ends)]


def join(tags, segments):
    problem, solution = '', ''
    problem_label, problem_match, solution_match = '', '', ''
    pairs = []

    for tag, segment in zip(tags, segments):
        if tag[1] == problem_tag:
            problem = segment
            problem_match = tag[0].group(0)
            problem_label = tag[0].group(1)
        else:
            solution = segment
            solution_match = tag[0].group(0)
            pairs.append((problem, solution, problem_label, problem_match, solution_match))

    return pairs


def write_pairs(output_file: Path, pairs):
    year = re.search(r'(\d{4})', output_file.stem).group(1)

    output_jsonl_text = ""
    for problem, solution, problem_label, problem_match, solution_match in pairs:
        output_jsonl_text += json.dumps(
            {
                'year': year,
                'problem_label': problem_label,
                'tier': 1,
                'problem': problem,
                'solution': solution,
                'problem_match': problem_match,
                'solution_match': solution_match
            },
            ensure_ascii=False
        ) + '\n'

    output_file.write_text(output_jsonl_text, encoding="utf-8")


def main():
    compet_base_path = Path(__file__).resolve().parent.parent
    compet_md_path = compet_base_path / "md"
    seg_output_path = compet_base_path / "segmented"

    total_problem_count = 0
    total_solution_count = 0

    for apmo_md in tqdm(list(compet_md_path.glob('**/*.md')), desc='Segmenting'):
        output_file = seg_output_path / apmo_md.relative_to(compet_md_path).with_suffix('.jsonl')
        output_file.parent.mkdir(parents=True, exist_ok=True)

        text = '\n' + apmo_md.read_text(encoding="utf-8")

        tags, problem_num = analyze(text)

        segments = segment(text, tags)
        pairs = join(tags, segments)     
        if pairs and problem_num > 0:
            write_pairs(output_file, pairs)

            total_problem_count += problem_num
            total_solution_count += len(pairs)
        else:
            logger.warning(f"No problem found in {apmo_md}")
        
    logger.info(f"Total problem count: {total_problem_count}")
    logger.info(f"Total solution count: {total_solution_count}")


if __name__ == '__main__':
    main()