"""抖音标准表情（评论区 emoji）名称 -> 图片 URL 映射。

抖音文字表情如 [酷拽]/[微笑] 通过 WS 以 message_type=7 的纯文本下发，
content 形如 {"text":"[酷拽]","aweType":700}，不带图片地址；
浏览器端靠本地表情表把 [name] 渲染成小图。这里拉取官方表情列表接口，
建立 name->url 映射，收到文字表情时补成可显示的贴纸。
"""

from __future__ import annotations

import logging
import re
import threading
import time
from typing import Optional

logger = logging.getLogger("douyin_im.emoji")

_EMOJI_MAP: dict[str, str] = {}
_FETCHED_AT: float = 0.0
_TTL = 6 * 3600  # 6 小时刷新一次
_lock = threading.Lock()

_BRACKET_RE = re.compile(r"^\[[^\[\]]{1,24}\]$")


def has_emoji_map() -> bool:
    return bool(_EMOJI_MAP)


def is_fresh() -> bool:
    return bool(_EMOJI_MAP) and (time.time() - _FETCHED_AT) < _TTL


def set_emoji_map(mapping: dict[str, str]) -> None:
    global _EMOJI_MAP, _FETCHED_AT
    if mapping:
        with _lock:
            _EMOJI_MAP = dict(mapping)
            _FETCHED_AT = time.time()


def lookup_emoji_url(name: str) -> str:
    """name 可带或不带中括号，返回标准表情图片 URL（无则空串）。"""
    if not name:
        return ""
    key = name.strip()
    if not key:
        return ""
    if not key.startswith("["):
        key = f"[{key}]"
    return _EMOJI_MAP.get(key, "")


def looks_like_emoji_token(text: str) -> bool:
    return bool(_BRACKET_RE.match((text or "").strip()))


def fetch_emoji_map(session) -> dict[str, str]:
    """用账号会话拉取官方表情列表，返回 {display_name: url}。失败返回 {}。"""
    try:
        import requests

        from .auth import DouyinAuth
        from .dy_util import generate_a_bogus, generate_msToken, splice_url

        auth = DouyinAuth.from_im_session(session)
        ua = session.user_agent
        s_v_web_id = session.cookies.get("s_v_web_id", "") if session.cookies else ""
        params = {
            "device_platform": "webapp",
            "aid": "6383",
            "channel": "channel_pc_web",
            "pc_client_type": "1",
            "version_code": "170400",
            "version_name": "17.4.0",
            "cookie_enabled": "true",
            "browser_language": "zh-CN",
            "browser_platform": "Win32",
            "browser_name": "Mozilla",
            "browser_online": "true",
            "verifyFp": s_v_web_id,
            "fp": s_v_web_id,
            "webid": session.web_id or session.device_id or "",
            "msToken": generate_msToken(),
        }
        params["a_bogus"] = generate_a_bogus(splice_url(params), user_agent=ua)
        headers = {
            "User-Agent": ua,
            "Referer": "https://www.douyin.com/",
            "Accept": "application/json, text/plain, */*",
            "Cookie": session.cookie_header(),
        }
        resp = requests.get(
            "https://www.douyin.com/aweme/v1/web/emoji/list",
            params=params,
            headers=headers,
            cookies=auth.cookie if getattr(auth, "cookie", None) else None,
            verify=False,
            timeout=20,
        )
        data = resp.json()
        mapping: dict[str, str] = {}
        for item in data.get("emoji_list") or []:
            name = item.get("display_name")
            urls = (item.get("emoji_url") or {}).get("url_list") or []
            if name and urls:
                mapping[name] = urls[0]
        logger.info("Fetched %d douyin emoji", len(mapping))
        return mapping
    except Exception as e:
        logger.warning("fetch_emoji_map failed: %s", e)
        return {}


def ensure_emoji_map(session) -> None:
    """若缓存为空/过期则拉取（同步阻塞，调用方建议放线程）。"""
    if is_fresh():
        return
    mapping = fetch_emoji_map(session)
    if mapping:
        set_emoji_map(mapping)