import re
import json

from tqdm import tqdm
from loguru import logger

from pathlib import Path
from typing import Tuple, List


project_root = Path(__file__).parent.parent.parent
problem_tag = 'Problem'
solution_tag = 'Solution'
problem_pattern = re.compile(r'(?:\n|# )Opgave\s+(\d+)\.', re.IGNORECASE)
solution_pattern = re.compile(r'(?:\n|# )Oplossing(?:\s+(\d+)\.|\s+(I{1,3}|IV|V|VI{1,3}|IX)\.|\.|\n|:)', re.IGNORECASE)


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.
    """
    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().rstrip("#").strip() for start, end in zip(starts, ends)]


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

    has_solution = any([tag[1] == solution_tag for tag in tags])

    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) if tag[0].group(1) else tag[0].group(2)

            # If there is no solution, add an empty solution
            if not has_solution:
                pairs.append((problem, '', problem_label, problem_match, ''))
        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,
                'tier': 'T1',
                'problem_label': problem_label,
                'problem_type': None,
                "exam": "Dutch_TST", 
                'problem': problem,
                'solution': solution,
                'metadata': {
                    'resource_path': output_file.relative_to(project_root).as_posix(),
                    '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 dutch_tst_md in tqdm(list(compet_md_path.glob('**/*.md')), desc='Segmenting'):
        output_file = seg_output_path / dutch_tst_md.relative_to(compet_md_path).with_suffix('.jsonl')
        output_file.parent.mkdir(parents=True, exist_ok=True)

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

        if all([y not in dutch_tst_md.name for y in ["2007", "2008"]]):
            tags, problem_num = analyze(text)

            if problem_num != 4 and problem_num != 5:
                logger.warning(f"{dutch_tst_md} problem number is {problem_num}")

            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 {dutch_tst_md}")
    
    logger.info(f"Total problem count: {total_problem_count}")
    logger.info(f"Total solution count: {total_solution_count}")


if __name__ == '__main__':
    main()