from django.conf import settings
from django.core.mail import EmailMultiAlternatives
from django.template.loader import get_template

from input.models import Project

from .attachments import collect_and_attach

__all__ = [
    'build_email',
    'send_email',
    'collect_and_attach',
    'send_applicant_decision_mail',
    'send_staff_decision_mail',
    'send_decision_mails',
]


def build_email(template_name: str, context: dict, subject: str, *recipients: str, **kwargs):
    body = get_template(f'mails/{template_name}.txt').render(context)
    html = get_template(f'mails/{template_name}.html').render(context)

    kwargs.setdefault('from_email', settings.IF_EMAIL)

    kwargs['subject'] = subject
    kwargs['body'] = body
    kwargs['to'] = recipients

    email = EmailMultiAlternatives(**kwargs)

    email.attach_alternative(html, 'text/html')

    return email


def send_email(template_name: str, context: dict, subject: str, *recipients: str, fail_silently=False, **kwargs):
    return build_email(template_name, context, subject, *recipients, **kwargs).send(fail_silently)


def get_decision_mail_context(obj: Project):
    """
    Build a minimal, consistent context for decision mails (applicant & staff).
    """

    return {
        'project': obj,
        'data': {
            'realname': obj.realname or obj.email,
            'name': obj.name,
        },
    }


def send_base_decision_mail(obj: Project, scope: str, subject: str, recipient: str):
    context = get_decision_mail_context(obj)
    decision = 'granted' if obj.granted else 'denied'
    decision_label = 'bewilligt' if obj.granted else 'abgelehnt'
    subject = subject.format(name=obj.name, decision=decision_label)

    return send_email(f'approval_{scope}_{decision}', context, subject, recipient)


def send_applicant_decision_mail(obj: Project):
    """
    Send a decision email to the applicant after manual approval/denial.
    """

    if recipient := obj.email:
        return send_base_decision_mail(obj, 'applicant', 'Deine Förderanfrage „{name}“ – {decision}', recipient)

    return 0


def send_staff_decision_mail(obj: Project):
    """
    Send a decision email to the internal team (staff) after approval/denial.
    """

    return send_base_decision_mail(obj, 'staff', 'Entscheidung: {name} ({decision})', settings.IF_EMAIL)


def send_decision_mails(obj: Project):
    return send_applicant_decision_mail(obj) + send_staff_decision_mail(obj)