import subprocess
import time
import os
from pathlib import Path
from typing import Dict, Any

import yaml

from .models import RunRequest, RunResult


def load_config(config_path: str | Path = None) -> Dict[str, Any]:
    """加载配置，默认使用 AGENT_CONFIG 或 ./config.yaml。"""
    if config_path is None:
        env_path = os.environ.get("AGENT_CONFIG")
        config_path = Path(env_path) if env_path else Path(__file__).resolve().parent.parent / "config.yaml"
    config_path = Path(config_path)
    with open(config_path, "r", encoding="utf-8") as f:
        return yaml.safe_load(f) or {}


def resolve_tool(config: Dict[str, Any], tool_name: str) -> Path:
    tools = config.get("tools", {})
    if tool_name not in tools:
        raise ValueError(f"未知工具: {tool_name}")
    tool_path = Path(tools[tool_name]["path"])
    if not tool_path.exists():
        raise FileNotFoundError(f"工具不存在: {tool_path}")
    return tool_path


def run_tool(config: Dict[str, Any], req: RunRequest) -> RunResult:
    start = time.time()
    defaults = config.get("run_defaults", {})

    tool_path = resolve_tool(config, req.tool)
    workdir = Path(req.workdir or config.get("base_workdir", ".")).resolve()
    workdir.mkdir(parents=True, exist_ok=True)

    # 处理参数与环境
    args = [str(tool_path)] + req.args
    env = os.environ.copy()
    if config.get("env"):
        env.update({k: str(v) for k, v in config["env"].items()})
    if req.env:
        env.update({k: str(v) for k, v in req.env.items()})

    timeout = req.timeout or defaults.get("timeout")
    capture_output = req.capture_output if req.capture_output is not None else defaults.get("capture_output", True)
    strip_output = req.strip_output if req.strip_output is not None else defaults.get("strip_output", True)

    try:
        completed = subprocess.run(
            args,
            cwd=str(workdir),
            env=env,
            timeout=timeout,
            capture_output=capture_output,
            text=True,
            check=False,
        )
        stdout = completed.stdout if capture_output else None
        stderr = completed.stderr if capture_output else None
        if strip_output:
            stdout = stdout.strip() if stdout is not None else None
            stderr = stderr.strip() if stderr is not None else None

        elapsed = time.time() - start
        return RunResult(
            success=completed.returncode == 0,
            return_code=completed.returncode,
            stdout=stdout,
            stderr=stderr,
            elapsed=elapsed,
            tool_path=str(tool_path),
            workdir=str(workdir),
        )
    except Exception as exc:
        elapsed = time.time() - start
        return RunResult(
            success=False,
            return_code=None,
            stdout=None,
            stderr=str(exc),
            elapsed=elapsed,
            tool_path=str(tool_path),
            workdir=str(workdir),
        )