"""Shell 执行: subprocess 跑命令,有黑名单拦明显危险操作。"""
from __future__ import annotations

import subprocess

from .base import Tool


class ShellTool(Tool):
    name = "shell"
    description = (
        "Execute a shell command and return stdout/stderr/exit_code. "
        "Default 60s timeout. Working directory is the agent's base dir."
    )
    parameters = {
        "type": "object",
        "properties": {
            "command": {"type": "string"},
            "timeout": {"type": "integer", "default": 60, "description": "Seconds before kill"},
        },
        "required": ["command"],
    }

    BLOCKED_PATTERNS = (
        "rm -rf /",
        "rm -rf ~",
        "rm -rf $HOME",
        ":(){ :|:& };:",
        "mkfs",
        "dd if=/dev/zero",
        "> /dev/sda",
        "format c:",
    )

    def execute(self, command: str, timeout: int = 60) -> str:
        normalized = command.lower()
        for pat in self.BLOCKED_PATTERNS:
            if pat in normalized:
                return f"[Error] blocked dangerous command pattern: {pat!r}"

        try:
            result = subprocess.run(
                command,
                shell=True,
                cwd=str(self.base_dir),
                capture_output=True,
                timeout=timeout,
                text=True,
                encoding="utf-8",
                errors="replace",
            )
        except subprocess.TimeoutExpired:
            return f"[Error] command timed out after {timeout}s"
        except FileNotFoundError as e:
            return f"[Error] {e}"

        parts = []
        if result.stdout:
            parts.append(f"[stdout]\n{result.stdout.rstrip()}")
        if result.stderr:
            parts.append(f"[stderr]\n{result.stderr.rstrip()}")
        parts.append(f"[exit {result.returncode}]")
        return "\n".join(parts)