from .slider_captcha import (
    generate_slider_captcha as _base_generate,
    verify_slider_captcha as _base_verify,
    verify_slider_trajectory as _base_verify_traj,
    SliderCaptchaError,
)

from .rate_limit import check_rate_limit

# 频控阈值：单 IP 10 秒内最多 6 次生成（普通用户基本用不到这个量）
SLIDER_GENERATE_LIMIT = 6
SLIDER_GENERATE_WINDOW = 10  # 秒

# 验证失败计数：单 IP 5 分钟内累计 10 次失败即拒绝继续验证，
# 防止对单 captcha_key 失败重试耗尽缓存/拖慢接口
SLIDER_VERIFY_FAIL_LIMIT = 10
SLIDER_VERIFY_FAIL_WINDOW = 300  # 秒


def _client_ip(request) -> str:
    fwd = request.META.get('HTTP_X_FORWARDED_FOR')
    if fwd:
        return fwd.split(',')[0].strip()
    return request.META.get('REMOTE_ADDR', '')


def generate_slider_captcha(request=None):
    if request is not None:
        ip = _client_ip(request)
        if ip and not check_rate_limit('slider_gen', ip, SLIDER_GENERATE_LIMIT, SLIDER_GENERATE_WINDOW):
            from utils.response_codes import ResponseCode, create_standardized_error_response
            from rest_framework import status
            return create_standardized_error_response(
                code=ResponseCode.RATE_LIMITED,
                message='请求过于频繁，请稍后再试',
                status_code=status.HTTP_429_TOO_MANY_REQUESTS,
            )
    return _base_generate()


def verify_slider_captcha(captcha_key: str, x_position: int, request=None) -> bool:
    ok = _base_verify(captcha_key, x_position)
    if request is not None and not ok:
        ip = _client_ip(request)
        if ip:
            check_rate_limit('slider_fail', ip, SLIDER_VERIFY_FAIL_LIMIT, SLIDER_VERIFY_FAIL_WINDOW)
    return ok


def verify_slider_trajectory(captcha_key: str, x_position: int, trajectory, request=None) -> bool:
    ok = _base_verify_traj(captcha_key, x_position, trajectory)
    if request is not None and not ok:
        ip = _client_ip(request)
        if ip:
            check_rate_limit('slider_fail', ip, SLIDER_VERIFY_FAIL_LIMIT, SLIDER_VERIFY_FAIL_WINDOW)
    return ok


def is_captcha_error(err) -> bool:
    return isinstance(err, SliderCaptchaError)