from __future__ import annotations

import logging
from io import StringIO

from exporter.config import GlobalConfig
from exporter.logging_utils import DeviceLoggerAdapter, DeviceFieldFilter, init_logging


def _capture_log_output(logger: logging.Logger) -> tuple[StringIO, logging.Handler]:
    stream = StringIO()
    handler = logging.StreamHandler(stream)
    formatter = logging.Formatter(
        fmt="%(asctime)s %(levelname)s [%(name)s] device=%(device)s %(message)s",
        datefmt="%Y-%m-%dT%H:%M:%S%z",
    )
    handler.setFormatter(formatter)
    logger.addHandler(handler)
    logger.setLevel(logging.INFO)
    return stream, handler


def test_device_logger_adapter_injects_device() -> None:
    logger = logging.getLogger("test_logger_adapter_injects_device")
    stream, handler = _capture_log_output(logger)
    try:
        adapter = DeviceLoggerAdapter(logger, {"device": "dev1"})
        adapter.info("hello world")
        output = stream.getvalue()
    finally:
        logger.removeHandler(handler)

    assert "device=dev1" in output
    # 简单校验时间格式中包含 "T"（ISO8601 风格）
    assert "T" in output.split()[0]


def test_device_logger_fallback_device_dash() -> None:
    logger = logging.getLogger("test_logger_adapter_fallback")
    stream, handler = _capture_log_output(logger)
    try:
        # 不在 extra 中显式提供 device，Adapter 应该使用 "-" 作为默认值
        adapter = DeviceLoggerAdapter(logger, {})
        adapter.info("no device context")
        output = stream.getvalue()
    finally:
        logger.removeHandler(handler)

    assert "device=-" in output


def test_init_logging_configures_root_logger_handlers() -> None:
    """验证 init_logging 根据 GlobalConfig 初始化根 logger。"""
    gc = GlobalConfig(
        log_level="INFO",
        log_to_stdout=True,
        log_file="",
    )
    # 调用被测函数
    init_logging(gc)

    root = logging.getLogger()
    # 至少应该有一个 handler（stdout）
    assert root.handlers, "root logger should have at least one handler"

    for handler in root.handlers:
        fmt = handler.formatter._fmt  # type: ignore[attr-defined]
        datefmt = handler.formatter.datefmt  # type: ignore[attr-defined]
        assert "device=%(device)s" in fmt
        assert "%Y-%m-%dT%H:%M:%S%z" == datefmt

    # 至少有一个 handler 安装了 DeviceFieldFilter，保证没有 device 字段的记录也能格式化
    assert any(
        isinstance(flt, DeviceFieldFilter)
        for handler in root.handlers
        for flt in handler.filters
    )