# -*- coding: utf-8 -*-
"""共享的 Android 工具函数，可被框架内外复用。"""

from __future__ import annotations

import logging
import re
import time
from typing import Callable, Optional

logger = logging.getLogger(__name__)


def get_current_package(
    adb_shell_func: Callable[[str], str],
    max_attempts: int = 3,
    retry_delay: float = 0.5,
) -> Optional[str]:
    """Read the foreground package via ``dumpsys``, retrying transient failures.

    Args:
        adb_shell_func: A callable that accepts a shell command string and
            returns the stdout text.  Example::

                lambda cmd: adb_client.shell(cmd)
        max_attempts: Maximum retry attempts for transient failures.
        retry_delay: Seconds to wait between retries.

    Returns:
        The foreground package name, or ``None`` if it could not be determined.
    """
    for attempt in range(max_attempts):
        try:
            focused_app = adb_shell_func("dumpsys window | grep mFocusedApp")
            if focused_app:
                matches = re.findall(
                    r"mFocusedApp=ActivityRecord\{[a-f0-9]+\s+\S+\s+([^/]+)/",
                    focused_app,
                )
                if matches:
                    return matches[-1]

            current_focus = adb_shell_func("dumpsys window | grep mCurrentFocus")
            if current_focus:
                matches = re.findall(
                    r"Window\{[a-f0-9]+\s+\S+\s+([^/]+)/",
                    current_focus,
                )
                if matches:
                    return matches[-1]

            resumed_activity = adb_shell_func("dumpsys activity activities | grep mResumedActivity")
            if resumed_activity:
                matches = re.findall(
                    r"\{[a-f0-9]+\s+\S+\s+([^/]+)/",
                    resumed_activity,
                )
                if matches:
                    return matches[-1]

            if attempt < max_attempts - 1:
                time.sleep(retry_delay)
        except Exception as exc:
            if attempt < max_attempts - 1:
                time.sleep(retry_delay)
                continue
            logger.error("Failed to get current package: %s", exc)
            return None

    logger.warning("Failed to get package name after %d attempts", max_attempts)
    return None