# Copyright (c) 2013, Web Notes Technologies Pvt. Ltd. and Contributors
# MIT License. See license.txt 

from __future__ import unicode_literals
import webnotes
import HTMLParser
import urllib
from webnotes import msgprint, throw, _
from webnotes.utils.email_lib.smtp import SMTPServer, send
from webnotes.utils.email_lib.email_body import get_email, get_formatted_html
from webnotes.utils.email_lib.html2text import html2text
from webnotes.utils import cint, get_url, nowdate

class BulkLimitCrossedError(webnotes.ValidationError): pass

def send(recipients=None, sender=None, doctype='Profile', email_field='email',
		subject='[No Subject]', message='[No Content]', ref_doctype=None, ref_docname=None,
		add_unsubscribe_link=True):
	def is_unsubscribed(rdata):
		if not rdata: 
			return 1
		return cint(rdata.unsubscribed)

	def check_bulk_limit(new_mails):
		this_month = webnotes.conn.sql("""select count(*) from `tabBulk Email` where
			month(creation)=month(%s)""" % nowdate())[0][0]

		monthly_bulk_mail_limit = webnotes.conf.get('monthly_bulk_mail_limit') or 500

		if this_month + len(recipients) > monthly_bulk_mail_limit:
			throw("{bulk} ({limit}) {cross}".format(**{
				"bulk": _("Monthly Bulk Mail Limit"),
				"limit": monthly_bulk_mail_limit,
				"cross": _("crossed")
			}), exc=BulkLimitCrossedError)

	def update_message(formatted, doc, add_unsubscribe_link):
		updated = formatted
		if add_unsubscribe_link:
			unsubscribe_link = """<div style="padding: 7px; border-top: 1px solid #aaa;
				margin-top: 17px;">
				<small><a href="%s/?%s">
				Unsubscribe</a> from this list.</small></div>""" % (get_url(), 
				urllib.urlencode({
					"cmd": "webnotes.utils.email_lib.bulk.unsubscribe",
					"email": doc.get(email_field),
					"type": doctype,
					"email_field": email_field
				}))
				
			updated = updated.replace("<!--unsubscribe link here-->", unsubscribe_link)
			
		return updated
	
	if not recipients: recipients = []
	if not sender or sender == "Administrator":
		sender = webnotes.conn.get_value('Email Settings', None, 'auto_email_id')
	check_bulk_limit(len(recipients))
	
	formatted = get_formatted_html(subject, message)

	for r in filter(None, list(set(recipients))):
		rdata = webnotes.conn.sql("""select * from `tab%s` where %s=%s""" % (doctype, 
			email_field, '%s'), (r,), as_dict=1)

		doc = rdata and rdata[0] or {}
				
		if not is_unsubscribed(doc):
			# add to queue
			updated = update_message(formatted, doc, add_unsubscribe_link)
			try:
				text_content = html2text(updated)
			except HTMLParser.HTMLParseError:
				text_content = "[See html attachment]"
			
			add(r, sender, subject, updated, text_content, ref_doctype, ref_docname)

def add(email, sender, subject, formatted, text_content=None, 
	ref_doctype=None, ref_docname=None):
	"""add to bulk mail queue"""	
	e = webnotes.doc('Bulk Email')
	e.sender = sender
	e.recipient = email
	try:
		e.message = get_email(email, sender=e.sender, formatted=formatted, subject=subject, 
			text_content=text_content).as_string()
	except webnotes.ValidationError:
		# bad email id - don't add to queue
		return
		
	e.status = 'Not Sent'
	e.ref_doctype = ref_doctype
	e.ref_docname = ref_docname
	e.save()
	
@webnotes.whitelist(allow_guest=True)
def unsubscribe():
	doctype = webnotes.form_dict.get('type')
	field = webnotes.form_dict.get('email_field')
	email = webnotes.form_dict.get('email')

	webnotes.conn.sql("""update `tab%s` set unsubscribed=1
		where `%s`=%s""" % (doctype, field, '%s'), (email,))
	
	if not webnotes.form_dict.get("from_test"):
		webnotes.conn.commit()

	webnotes.local.message_title = "Unsubscribe"
	webnotes.local.message = "<h3>Unsubscribed</h3><p>%s has been successfully unsubscribed.</p>" % email

	webnotes.response['type'] = 'page'
	webnotes.response['page_name'] = 'message.html'
	
def flush(from_test=False):
	"""flush email queue, every time: called from scheduler"""
	smtpserver = SMTPServer()
	
	auto_commit = not from_test
	
	if webnotes.flags.mute_emails or webnotes.conf.get("mute_emails") or False:
		msgprint(_("Emails are muted"))
		from_test = True
		
	for i in xrange(500):		
		email = webnotes.conn.sql("""select * from `tabBulk Email` where 
			status='Not Sent' limit 1 for update""", as_dict=1)
		if email:
			email = email[0]
		else:
			break
			
		webnotes.conn.sql("""update `tabBulk Email` set status='Sending' where name=%s""", 
			(email["name"],), auto_commit=auto_commit)
		try:
			if not from_test:
				smtpserver.sess.sendmail(email["sender"], email["recipient"], email["message"])

			webnotes.conn.sql("""update `tabBulk Email` set status='Sent' where name=%s""", 
				(email["name"],), auto_commit=auto_commit)

		except Exception, e:
			webnotes.conn.sql("""update `tabBulk Email` set status='Error', error=%s 
				where name=%s""", (unicode(e), email["name"]), auto_commit=auto_commit)

def clear_outbox():
	"""remove mails older than 30 days in Outbox"""
	webnotes.conn.sql("""delete from `tabBulk Email` where
		datediff(now(), creation) > 30""")