#!/usr/bin/env python3
import re
import csv
import argparse
from pathlib import Path

FRONTMATTER_RE = re.compile(r"^---\s*\n(.*?)\n---\s*\n", re.S)
FENCE_RE = re.compile(r"^```([^\n]*)\n(.*?)\n```", re.S | re.M)
DATE_DIR_RE = re.compile(r"\d{4}-\d{2}-\d{2}")

def find_date(path: Path):
    for p in path.parents:
        if DATE_DIR_RE.fullmatch(p.name):
            return p.name
    return ""

def parse_frontmatter(text: str):
    m = FRONTMATTER_RE.match(text)
    if not m:
        return {}, text
    fm_raw = m.group(1)
    rest = text[m.end():]
    tags = []
    # simple tags parsing: look for lines under "tags:"
    if re.search(r"^\s*tags\s*:\s*$", fm_raw, re.M):
        in_tags = False
        for line in fm_raw.splitlines():
            if re.match(r"^\s*tags\s*:\s*$", line):
                in_tags = True
                continue
            if in_tags:
                mm = re.match(r"^\s*-\s*(.+)$", line)
                if mm:
                    tags.append(mm.group(1).strip())
                else:
                    break
    # also try single-line tags: tags: [a, b]
    if not tags:
        m2 = re.search(r"tags\s*:\s*\[([^\]]+)\]", fm_raw)
        if m2:
            tags = [t.strip() for t in m2.group(1).split(",")]
    return {"tags": tags}, rest

def extract_question_answer(body: str):
    # find first fenced block (prefer spoiler)
    fences = list(FENCE_RE.finditer(body))
    spoiler = None
    for f in fences:
        info = (f.group(1) or "").lower()
        if "spoiler" in info:
            spoiler = f
            break
    if spoiler is None and fences:
        spoiler = fences[0]
    if spoiler:
        answer = spoiler.group(2).strip()
        question = (body[:spoiler.start()]).strip()
    else:
        # fallback: everything is question, no answer
        answer = ""
        question = body.strip()
    return question, answer

def main(root: Path, out: Path):
    rows = []
    for md in root.rglob("*.md"):
        rel = md.relative_to(root)
        date = find_date(md.parent)
        qnum = md.stem
        text = md.read_text(encoding="utf-8")
        fm, body = parse_frontmatter(text)
        tags = fm.get("tags", [])
        # choose first tag that's not biokemi or provfråga
        category = ""
        for t in tags:
            if t.lower() not in ("biokemi", "provfråga"):
                category = t
                break
        question, answer = extract_question_answer(body)
        # normalize whitespace
        question = re.sub(r"\s+", " ", question).strip()
        answer = re.sub(r"\s+", " ", answer).strip()
        details = f"{category}; {date} {qnum} {answer}"
        rows.append((question, details))
    # write CSV with semicolon delimiter and quoting
    out.parent.mkdir(parents=True, exist_ok=True)
    with out.open("w", encoding="utf-8", newline="") as f:
        writer = csv.writer(f)
        writer.writerow(["question", "details"])
        for r in rows:
            writer.writerow(r)

if __name__ == "__main__":
    ap = argparse.ArgumentParser(description="Extract questions+answers to CSV")
    ap.add_argument("root", nargs="?", default="content", help="root content folder (default: content)")
    ap.add_argument("-o", "--out", default="output.csv", help="output CSV file (default: output.csv)")
    args = ap.parse_args()
    main(Path(args.root), Path(args.out))