import logging
import random
import secrets
import string
import time

from app.core.config import settings

logger = logging.getLogger(__name__)

SMS_CODE_TTL_SECONDS = 300  # 5分钟有效期
_sms_codes: dict[str, tuple[str, float]] = {}


def _send_sms_aliyun(phone: str, code: str) -> bool:
    """通过阿里云发送短信"""
    try:
        from alibabacloud_dysmsapi20170525.client import Client
        from alibabacloud_dysmsapi20170525 import models as dysmsapi_models
        from alibabacloud_tea_openapi import models as open_api_models
        
        config = open_api_models.Config(
            access_key_id=settings.aliyun_access_key_id,
            access_key_secret=settings.aliyun_access_key_secret,
        )
        config.endpoint = "dysmsapi.aliyuncs.com"
        client = Client(config)
        
        request = dysmsapi_models.SendSmsRequest(
            phone_numbers=phone,
            sign_name=settings.aliyun_sms_sign_name,
            template_code=settings.aliyun_sms_template_code,
            template_param=f'{{"code":"{code}"}}',
        )
        response = client.send_sms(request)
        
        if response.body.code == "OK":
            logger.info(f"[阿里云短信] 发送成功: {phone}")
            return True
        else:
            logger.error(f"[阿里云短信] 发送失败: {phone}, 错误: {response.body.message}")
            return False
    except ImportError:
        logger.error("[阿里云短信] 未安装依赖，请执行: pip install alibabacloud-dysmsapi20170525")
        return False
    except Exception as e:
        logger.error(f"[阿里云短信] 发送异常: {phone}, 异常: {str(e)}")
        return False


def _send_sms_local(phone: str, code: str) -> bool:
    """本地测试模式：将验证码打印到终端"""
    print(f"\n{'='*50}")
    print(f"[短信验证码] 手机号: {phone}")
    print(f"[短信验证码] 验证码: {code}")
    print(f"[短信验证码] 有效期: {SMS_CODE_TTL_SECONDS}秒")
    print(f"{'='*50}\n")
    logger.info(f"[本地短信] 验证码已生成: {phone} -> {code}")
    return True


def send_sms(phone: str, code: str) -> bool:
    """发送短信验证码（根据配置选择发送方式）"""
    if settings.sms_mode == "aliyun":
        return _send_sms_aliyun(phone, code)
    else:
        return _send_sms_local(phone, code)


def generate_sms_code(phone: str) -> str:
    """生成短信验证码"""
    clean_expired_codes()
    code = "".join(random.choices(string.digits, k=6))
    sms_id = secrets.token_urlsafe(16)
    _sms_codes[sms_id] = (code, time.time() + SMS_CODE_TTL_SECONDS)
    
    # 发送短信
    send_sms(phone, code)
    
    return sms_id


def verify_sms_code(sms_id: str, code: str) -> bool:
    """验证短信验证码"""
    clean_expired_codes()
    record = _sms_codes.pop(sms_id, None)
    if not record:
        return False
    expected, expires_at = record
    if expires_at < time.time():
        return False
    return expected == code.strip()


def clean_expired_codes() -> None:
    """清理过期的验证码"""
    now = time.time()
    expired = [sms_id for sms_id, (_, expires_at) in _sms_codes.items() if expires_at < now]
    for sms_id in expired:
        _sms_codes.pop(sms_id, None)