#!/usr/bin/env python

from datetime import datetime, timedelta, timezone
from random import choice, randint, seed

NUM_COMMENTS = 600
ORIG_POSTS = int(NUM_COMMENTS / 10)
DAY_SECONDS = 24 * 60 * 60
START = datetime.now(tz=timezone.utc) - timedelta(seconds=DAY_SECONDS)
# random interval between a post and a reply to it - range from 0 to this
DELAY_INTERVAL = DAY_SECONDS / 12

# deterministic
seed(0)


class Comment:
    def __init__(self, num: int, replies: list["Comment"]):
        self.content: int = num
        self.replies: list["Comment"] = replies
        self.post_date: datetime | None = None
        self.level: int | None = None

    def __lt__(self, other: "Comment"):
        return self.post_date < other.post_date

    def total_children(self) -> int:
        return 1 + sum([c.total_children() for c in self.replies])



def flatten_comments(comments: list[Comment]) -> list[Comment]:
    return sorted(
        {
            c for c in
            [
                r for c in comments
                for r in
                [
                    c, *flatten_comments(c.replies)
                ]
            ]
        }
    )


# all comments
comments = [Comment(i, []) for i in range(NUM_COMMENTS)]
# set the first one as root of the tree
comments[0].post_date = START
comments[0].level = 0

# split into original posts and replies
posts, replies = comments[:ORIG_POSTS], comments[ORIG_POSTS:]

# for all but the first post, set the date later than the first, and note they're top-level
for post in posts[1:]:
    post.post_date = START + timedelta(seconds=randint(0, DAY_SECONDS))
    post.level = 0

# assign each reply a randomly-chosen parent.  Set its level 1 higher than its parent, a post
# date later than its parent, and add it to that parent's replies
for reply in replies:
    parent = choice(posts)
    reply.post_date = parent.post_date + timedelta(seconds=randint(0, DELAY_INTERVAL))
    reply.level = parent.level + 1
    parent.replies.append(reply)
    # then move the reply into the posts list, so it can be assigned replies as well
    posts.append(reply)

flattened = flatten_comments(comments)

for comment in flattened:
    print(
        f"{comment.post_date.isoformat()} - "
        f"level {comment.level}: '{comment.content:-3d}' - "
        f"{len(comment.replies):-3d} replies - {comment.total_children():-3d} children"
    )