#!/usr/bin/env python3
"""
三省六部 · 公共工具函数
避免 read_json / now_iso 等基础函数在多个脚本中重复定义
"""
import os
import sys
import json, pathlib, datetime, shutil


def read_json(path, default=None):
    """安全读取 JSON 文件，失败返回 default"""
    try:
        return json.loads(pathlib.Path(path).read_text(encoding='utf-8'))
    except Exception:
        return default if default is not None else {}


def get_openclaw_home() -> pathlib.Path:
    """Return OpenClaw home directory, respecting OPENCLAW_HOME env var."""
    env = os.environ.get('OPENCLAW_HOME')
    if env:
        return pathlib.Path(env).expanduser()
    return pathlib.Path.home() / '.openclaw'


def now_iso():
    """返回 UTC ISO 8601 时间字符串（末尾 Z）"""
    return datetime.datetime.now(datetime.timezone.utc).isoformat().replace('+00:00', 'Z')


def today_str(fmt='%Y%m%d'):
    """返回今天日期字符串，默认 YYYYMMDD"""
    return datetime.date.today().strftime(fmt)


def safe_name(s: str) -> bool:
    """检查名称是否只含安全字符（字母、数字、下划线、连字符、中文）"""
    import re
    return bool(re.match(r'^[a-zA-Z0-9_\-\u4e00-\u9fff]+$', s))


def python_bin() -> str:
    """返回当前 Python 解释器路径，兼容 Windows（无 python3 命令）"""
    return sys.executable or shutil.which('python3') or shutil.which('python') or 'python3'


def validate_url(url: str, allowed_schemes=('https',), allowed_domains=None) -> bool:
    """校验 URL 合法性，防 SSRF"""
    from urllib.parse import urlparse
    try:
        parsed = urlparse(url)
        if parsed.scheme not in allowed_schemes:
            return False
        if allowed_domains and parsed.hostname not in allowed_domains:
            return False
        if not parsed.hostname:
            return False
        # 禁止内网地址
        import ipaddress
        try:
            ip = ipaddress.ip_address(parsed.hostname)
            if ip.is_private or ip.is_loopback or ip.is_reserved:
                return False
        except ValueError:
            pass  # hostname 不是 IP，放行
        return True
    except Exception:
        return False