emoji_update.py

import json
import re
import sys
from html.parser import HTMLParser
from json import JSONDecodeError
from pathlib import Path
from typing import Any, cast
from urllib.request import Request, urlopen

from chompjs import parse_js_object

EMOJI_JSON_REGEX = re.compile(r'(\{(\w+?:\[({names:.+?:surrogates:.+?},)*?{names:.+surrogates:.+?}\])+?}}),')


def get(url: str) -> str:
    return cast(bytes, urlopen(Request(url, data=None, headers={"User-Agent": ""})).read()).decode("utf8")  # noqa: S310


def convert_emoji_map(categories: dict[Any, Any]) -> dict[Any, Any]:
    return {
        **{
            name: emoji["surrogates"]
            for category in categories.values()
            for emoji in category
            for name in emoji["names"]
        },
        **{
            name: child["surrogates"]
            for category in categories.values()
            for emoji in category
            if "diversityChildren" in emoji
            for child in emoji["diversityChildren"]
            for name in child["names"]
        },
    }


class DiscordLoginPageParser(HTMLParser):
    def __init__(self) -> None:
        super().__init__()

        self.urls: list[str] = []

    def handle_starttag(self, tag: str, attrs: list[tuple[str, str | None]]) -> None:
        if tag != "script":
            return

        for name, value in attrs:
            if name != "src":
                continue

            if value and value.startswith("/assets/") and value.endswith(".js"):
                self.urls.append(f"https://discord.com{value}")

    def error(self, message: str) -> None:
        print(f"Error while parsing the Discord login page: {message}")


if __name__ == "__main__":
    login_page = get("https://discord.com/login")
    parser = DiscordLoginPageParser()
    parser.feed(login_page)

    emoji_json: Any | None = None

    for script_url in reversed(parser.urls):
        json_match = EMOJI_JSON_REGEX.search(get(script_url))
        # if "person_in_bed_tone5" in get(script_url):   # alternative search function, if regex broken
        #     print("🙀", script_url)
        if json_match:
            try:
                text = json_match.group(1)
                # thanks discord for using multiple encodings in one file
                text = re.sub(r"\\x\w\w", lambda x: x[0].encode().decode("unicode-escape"), text)
                emoji_json = parse_js_object(text)
                break
            except JSONDecodeError as e:
                print(
                    f"Error while decoding emoji JSON from {script_url} "
                    f"(position {json_match.start(0)}-{json_match.end(0)}): {e}"
                )

    if not emoji_json:
        print("Emoji map could not be found")
        sys.exit(1)

    result = convert_emoji_map(emoji_json)
    print(f"Found {len(result)} emojis including variations")

    with Path(__file__).parent.joinpath("PyDrocsid/emoji_map.json").open("w") as file:
        json.dump(result, file)