Twitter thread unnester

#!/usr/bin/env python3

import json


def read_json(file_name):
    with open(file_name) as input_file:
        return json.load(input_file)


def write_json(file_name, tweets):
    with open(file_name, "w") as output_file:
        json.dump(tweets, output_file, sort_keys=True, indent=2, ensure_ascii=False)


def count_deep(replies):
    total = len(replies)
    if total == 0:
        return total

    for reply in replies:
        inner_replies = reply.get("replies", [])
        if inner_replies:
            total += count_deep(inner_replies)

    return total


def is_flat(tweet):
    for reply in tweet.get("replies", []):
        if reply.get("replies", None):
            return False

    return True


def is_nested(tweet, recursive=False):
    replies = tweet.get("replies", [])
    if len(replies) != 1:
        return False

    reply = replies[0]
    while reply:
        replies = reply.get("replies", None)
        if not replies:
            return True

        if len(replies) > 1:
            return False

        reply = replies[0]


def is_wtf(tweet, recursive=False):
    replies = tweet.get("replies", [])
    if not replies:
        return recursive

    if len(replies) > 1:
        return


def unnest(tweet):
    tweet_replies = tweet.pop("replies", None)
    if not tweet_replies:
        return tweet

    unnested = []
    for reply in map(unnest, tweet_replies):
        replies: list = reply.pop("replies", [])
        replies.append(reply)

        unnested.extend(replies)

    if unnested:
        unnested.sort(key=lambda r: r["id"])
        tweet["replies"] = unnested

    return tweet


if __name__ == "__main__":
    tweets = read_json("./threads.json")

    multi_reply = []
    wtf_reply = []
    for tweet in tweets:
        if is_flat(tweet):
            multi_reply.append(tweet)
            continue

        if is_nested(tweet):
            multi_reply.append(unnest(tweet))
            continue

        wtf_reply.append(tweet)

    write_json("./threads_unnested.json", multi_reply)
    write_json("./threads_wtf.json", wtf_reply)