"""宿主机无关的外部命令发现。所有平台差异只允许留在这里。"""
from __future__ import annotations

import os
import shutil
import sys
from pathlib import Path


def adb_binary() -> str:
    configured = os.environ.get("AUTOTRAIN_ADB", "").strip()
    if configured:
        return configured
    if found := shutil.which("adb"):
        return found
    candidates = [
        Path("/opt/homebrew/share/android-commandlinetools/platform-tools/adb"),
        Path.home() / "Library/Android/sdk/platform-tools/adb",
        Path(os.environ.get("LOCALAPPDATA", "")) / "Android/Sdk/platform-tools/adb.exe",
        Path(os.environ.get("LOCALAPPDATA", "")) / "Android/Sdk/platform-tools/adb.exe",
        Path(os.environ.get("ANDROID_HOME", "")) / "platform-tools" / ("adb.exe" if sys.platform.startswith("win") else "adb"),
        Path(os.environ.get("ANDROID_SDK_ROOT", "")) / "platform-tools" / ("adb.exe" if sys.platform.startswith("win") else "adb"),
    ]
    for candidate in candidates:
        if candidate.is_file():
            return str(candidate)
    return "adb.exe" if sys.platform.startswith("win") else "adb"


def scrcpy_binary() -> str:
    return os.environ.get("AUTOTRAIN_SCRCPY", "").strip() or (shutil.which("scrcpy") or "scrcpy")