from django.conf import settings
from django.utils import timezone
from rest_framework.permissions import AllowAny
from rest_framework.response import Response
from rest_framework.views import APIView

from api_v1.models import AppVersion


APP_VERSION_CACHE_KEY = "app_version:latest"


def _coerce_version_part(value) -> int:
    return max(0, int(value or 0))


def _coerce_publish_date(value) -> str:
    return str(value or timezone.localdate().isoformat()).strip()


def build_app_version_payload(
    *,
    major,
    minor,
    build,
    download_url: str,
    force=False,
    publish_date=None,
    message: str = "",
) -> dict:
    return {
        "latest_version": {
            "major": _coerce_version_part(major),
            "minor": _coerce_version_part(minor),
            "build": _coerce_version_part(build),
        },
        "download_url": str(download_url or "").strip(),
        "force": bool(force),
        "publish_date": _coerce_publish_date(publish_date),
        "message": str(message or ""),
    }


def get_app_version_payload() -> dict:
    app_version = (
        AppVersion.objects.filter(is_current=True).order_by('-created_at').first()
        or AppVersion.objects.order_by('-created_at').first()
    )
    if app_version:
        return build_app_version_payload(
            major=app_version.major,
            minor=app_version.minor,
            build=app_version.build,
            download_url=app_version.download_url,
            force=app_version.force,
            publish_date=app_version.publish_date,
            message=app_version.message,
        )

    return build_app_version_payload(
        major=getattr(settings, "APP_LATEST_VERSION_MAJOR", 0),
        minor=getattr(settings, "APP_LATEST_VERSION_MINOR", 0),
        build=getattr(settings, "APP_LATEST_VERSION_BUILD", 0),
        download_url=getattr(settings, "APP_DOWNLOAD_URL", ""),
        force=getattr(settings, "APP_FORCE_UPDATE", False),
        publish_date=getattr(settings, "APP_PUBLISH_DATE", None),
        message=getattr(settings, "APP_VERSION_MESSAGE", ""),
    )


def set_cached_app_version_payload(
    *,
    major,
    minor,
    build,
    download_url: str,
    force=False,
    publish_date=None,
    message: str = "",
) -> dict:
    app_version = AppVersion.objects.create(
        major=major,
        minor=minor,
        build=build,
        download_url=download_url,
        force=force,
        publish_date=publish_date or timezone.localdate(),
        message=message,
        is_current=True,
    )
    return build_app_version_payload(
        major=app_version.major,
        minor=app_version.minor,
        build=app_version.build,
        download_url=app_version.download_url,
        force=app_version.force,
        publish_date=app_version.publish_date,
        message=app_version.message,
    )


class AppVersionView(APIView):
    permission_classes = [AllowAny]

    def get(self, request):
        return Response(get_app_version_payload())