''' custom events and event subsribers '''

from pyramid.events import subscriber
from pyramid.renderers import render
from pyramid_mailer import get_mailer
from pyramid_mailer.message import Message


# custom events

class UserNotification(object):
    ''' base class for user notification emails

    :param pyramid.request.Request request: current request object
    :param ordr.models.account.Users account: send notification to this user
    :param dict data: additional data to pass to the mail template
    :param str send_to: optional email address overriding user's email address
    '''

    #: subject of the notification
    subject = None

    #: template to render
    template = None

    def __init__(self, request, account, data=None, send_to=None):
        self.request = request
        self.account = account
        self.data = data
        self.send_to = send_to or account.email


class ActivationNotification(UserNotification):
    ''' user notification for account activation '''
    
    subject = '[ordr] Your account was activated'
    template = 'ordr:templates/emails/activation.jinja2'


class ChangeEmailNotification(UserNotification):
    ''' user notification for verifying a change of the mail address '''
    
    subject = '[ordr] Verify New Email Address'
    template = 'ordr:templates/emails/email_change.jinja2'


class OrderStatusNotification(UserNotification):
    ''' user notification for order status change '''
    
    subject = '[ordr] Order Status Change'
    template = 'ordr:templates/emails/order.jinja2'

    
class PasswordResetNotification(UserNotification):
    ''' user notification for password reset link '''
    
    subject = '[ordr] Password Reset'
    template = 'ordr:templates/emails/password_reset.jinja2'


class RegistrationNotification(UserNotification):
    ''' user notification for account activation '''
    
    subject = '[ordr] Please verify your email address'
    template = 'ordr:templates/emails/registration.jinja2'


# subsribers for events

@subscriber(UserNotification)
def notify_user(event):
    ''' notify a user about an event '''
    body = render(
        event.template,
        {'user': event.account, 'data': event.data},
        event.request
        )
    message = Message(
        subject=event.subject,
        sender=event.request.registry.settings['mail.default_sender'],
        recipients=[event.send_to],
        html=body
        )
    mailer = get_mailer(event.request.registry)
    mailer.send(message)