old_comment_parser.py

"""Parse an old.reddit user comments listing into structured records.

Server-rendered HTML. Pure: HTML in -> list[dict] out. Each comment is a
`div.thing.comment` carrying the fields as data-* attributes; score + time come
from the tagline. Same 5-field schema as the Playwright comment scrapper:
subreddit, author, score, created_iso, permalink.
"""

from dataclasses import dataclass, asdict

from bs4 import BeautifulSoup

THING_SELECTOR = "div.thing.comment"


@dataclass
class Comment:
    subreddit: str | None
    author: str | None
    score: int | None        # comment votes
    created_iso: str | None  # comment timestamp
    permalink: str | None


def _score(thing):
    # Tagline renders three score spans (vote states); .unvoted is the real one.
    el = thing.select_one(".score.unvoted")
    if el and el.get("title"):
        try:
            return int(el["title"])
        except ValueError:
            return None
    return None


def _permalink(thing):
    rel = thing.get("data-permalink")
    return "https://www.reddit.com" + rel if rel else None


def _created(thing):
    t = thing.select_one(".tagline time")
    return t.get("datetime") if t else None


def parse_user_comments(html):
    """HTML -> list of comment dicts. Deduped by fullname, order preserved."""
    soup = BeautifulSoup(html, "html.parser")
    seen = set()
    out = []
    for thing in soup.select(THING_SELECTOR):
        key = thing.get("data-fullname") or thing.get("data-permalink")
        if key in seen:
            continue
        seen.add(key)
        out.append(
            asdict(
                Comment(
                    subreddit=thing.get("data-subreddit"),
                    author=thing.get("data-author"),
                    score=_score(thing),
                    created_iso=_created(thing),
                    permalink=_permalink(thing),
                )
            )
        )
    return out


def next_page_url(html):
    """Return the old.reddit 'next' page URL, or None at the end."""
    soup = BeautifulSoup(html, "html.parser")
    a = soup.select_one('.nextprev a[rel~="next"]')
    return a.get("href") if a else None