"""SMS delivery via the SAR Link SMS gateway.

    POST {SMS_API_URL}
    X-API-Key: {SMS_API_KEY}
    {"to": "+9607712345", "text": "..."}

With `SMS_API_URL`/`SMS_API_KEY` unset (dev) nothing is sent and the message is
logged instead, so the OTP flows stay usable without the gateway.
"""

import logging

import requests
from django.conf import settings

logger = logging.getLogger(__name__)

TIMEOUT_SECONDS = 10


def send_sms(mobile: str, text: str) -> bool:
    if not settings.SMS_API_URL or not settings.SMS_API_KEY:
        logger.warning("SMS not configured; would send to %s: %s", mobile, text)
        return False

    try:
        response = requests.post(
            settings.SMS_API_URL,
            json={"to": mobile, "text": text},
            headers={
                "X-API-Key": settings.SMS_API_KEY,
                "Content-Type": "application/json",
            },
            timeout=TIMEOUT_SECONDS,
        )
        response.raise_for_status()
    except requests.RequestException:
        logger.exception("Failed to send SMS to %s", mobile)
        return False

    logger.info("Sent SMS to %s", mobile)
    return True


def send_otp(mobile: str, code: str, purpose: str) -> bool:
    minutes = max(1, settings.OTP_TTL_SECONDS // 60)
    what = "registration" if purpose == "registration" else "login"
    return send_sms(
        mobile,
        f"{code} is your SAR Link {what} code. It expires in {minutes} minutes.",
    )


def send_registration_submitted(mobile: str) -> bool:
    return send_sms(
        mobile,
        "Thanks for registering with SAR Link. Your application is being "
        "reviewed and we'll text you once it's approved.",
    )


def send_registration_approved(mobile: str) -> bool:
    return send_sms(
        mobile,
        f"Your SAR Link registration is approved. Sign in at {settings.FRONTEND_URL}",
    )


def send_registration_rejected(mobile: str, reason: str = "") -> bool:
    tail = f" Reason: {reason}" if reason else ""
    return send_sms(
        mobile, f"Your SAR Link registration could not be approved.{tail}"
    )