"""微信主动推送工具(DESIGN §8.7 渠道抽象)。host-side,按 user_id 注入。

agent 在(交互 / 定时)run 里调:把一段文本 + 可选产物文件**主动推**到用户已绑的微信
(当前 ClawBot 个人微信;企业微信渠道后续在 `service.send_to_user` 内追加)。仅当渠道开关
在才挂(沿用「有开关才注册」§3.4)。

ClawBot 推送有 **24h 窗口**约束:用户超期未在微信里跟机器人说过话 / 从未开口 → 推不出,
工具返回明确 reason,agent 可改走 `send_email`。密钥/凭据只在 host 进程,绝不进沙箱。
"""
from __future__ import annotations

from pathlib import Path
from typing import Optional
from uuid import UUID

from core.wechat import service
from .base import Tool


def wechat_push_available() -> bool:
    """任一微信渠道可用(当前 = ClawBot 开关在;后续 or 企业微信配齐)。"""
    return service.clawbot_enabled()


_REASON_HINT = {
    "no_binding": "用户还没绑定微信(让其在 zcbot 网页扫码绑定)",
    "never_opened": "用户绑了但从未在微信里跟机器人说过话(主动推需先开口一次)",
    "token_stale": "距用户上次在微信互动已超 24h,主动推送窗口已过(让其发条消息即可恢复)",
}


class WechatPushTool(Tool):
    name = "wechat_push"
    description = (
        "Proactively push a short text message (and optionally one result file, e.g. a .docx/.pdf "
        "report) to the user's bound WeChat. Use when the user asks to send something to their "
        "WeChat, or when a scheduled task should deliver its output there. NOTE: WeChat push only "
        "works if the user has messaged the bot within the last ~24h; if it returns a window/binding "
        "error, fall back to send_email. The file path is relative to the working directory."
    )
    parameters = {
        "type": "object",
        "properties": {
            "text": {"type": "string", "description": "Message text to push (plain text)."},
            "file": {
                "type": "string",
                "description": "Optional path (relative to working dir) of one file to attach, e.g. 'report.docx'.",
            },
        },
        "required": ["text"],
    }

    def __init__(self, user_id: UUID, base_dir=None, user_root=None) -> None:
        super().__init__(base_dir=base_dir, user_root=user_root)
        self.user_id = user_id

    def execute(self, text: str = "", file: Optional[str] = None) -> str:
        text = (text or "").strip()
        if not text and not file:
            return "[Error] text 不能为空"

        fpath: Optional[str] = None
        if file and file.strip():
            p = self._resolve(file.strip()).resolve()
            if self.user_root is not None:
                try:
                    p.relative_to(self.user_root.resolve())
                except ValueError:
                    return f"[Error] 文件路径越界(必须在工作目录内): {file}"
            if not p.is_file():
                return f"[Error] 文件不存在: {file}"
            fpath = str(p)

        report = service.send_to_user(self.user_id, text, fpath)
        if report.delivered:
            n = "(含 1 个文件)" if fpath else ""
            return f"[ok] 已推送到微信 {n}".strip()

        if not report.results:
            return "[Error] 没有可用的微信渠道(未开启 / 未配置)"
        # 取首个失败原因给 agent 决定是否改走 send_email
        r = report.results[0]
        hint = _REASON_HINT.get(r.reason, r.reason)
        return f"[Error] 微信推送未送达({r.channel}: {r.reason})。{hint}。可改用 send_email。"