import jinja2
from channels.db import database_sync_to_async
from core.settings import PRIMARY_HOST

from notifications.models import MessageTemplate

TEMLATE_VARS = ['ticket_name', 'ticket_uuid', 'ticket_id', 'ticket_url',
                'current_state', 'previous_state', 'current_state_pretty', 'previous_state_pretty',
                'event_slug', 'event_name',
                'username', 'user_nick',
                'web_host']  # TODO customer_name, tracking_code


def limit_length(s, length=50):
    if len(s) > length:
        return s[:(length - 3)] + "..."
    return s


def ticket_url(ticket):
    eventslug = ticket.event.slug if ticket.event else "37C3"  # TODO 37C3 should not be hardcoded
    return f"https://{PRIMARY_HOST}/{eventslug}/ticket/{ticket.id}/"


def render_template(template, **kwargs):
    try:
        environment = jinja2.Environment()
        environment.filters['limit_length'] = limit_length
        tmpl = MessageTemplate.objects.get(name=template)
        template = environment.from_string(tmpl.message)
        return template.render(**kwargs, web_host=PRIMARY_HOST)
    except MessageTemplate.DoesNotExist:
        return None


def get_ticket_vars(ticket):
    states = list(ticket.state_changes.order_by('-timestamp'))
    return {
        'ticket_name': ticket.name,
        'ticket_uuid': ticket.short_uuid(),
        'ticket_id': ticket.id,
        'ticket_url': ticket_url(ticket),
        'current_state': states[0].state if states else 'none',
        'previous_state': states[1].state if len(states) > 1 else 'none',
        'current_state_pretty': states[0].get_state_display() if states else 'none',
        'previous_state_pretty': states[1].get_state_display() if len(states) > 1 else 'none',
        'event_slug': ticket.event.slug if ticket.event else "37C3",  # TODO 37C3 should not be hardcoded
        'event_name': ticket.event.name if ticket.event else "37C3",
    }


def render_auto_reply(ticket):
    return render_template('auto_reply', **get_ticket_vars(ticket))


def render_notification_new_ticket(ticket):
    return render_template('new_issue_notification', **get_ticket_vars(ticket))


def render_notification_reply_ticket(ticket):
    return render_template('reply_issue_notification', **get_ticket_vars(ticket))


async def render_notification_new_ticket_async(ticket):
    return await database_sync_to_async(render_notification_new_ticket)(ticket)


async def render_notification_reply_ticket_async(ticket):
    return await database_sync_to_async(render_notification_reply_ticket)(ticket)