# vim: fileencoding=utf8
# CCS CS Lab Main Utilities
#
# Douglas Thrift
#
# $Id$

from BeautifulSoup import BeautifulStoneSoup
import cgi
import common
from django.conf import settings
from django.core.mail import mail_admins
import ldap
import os.path
import pytz
import re
import socket

common.SSL_ROOT = os.path.abspath(os.path.join(os.path.dirname(__file__), '..', '..', 'ssl'))

ldap.set_option(ldap.OPT_PROTOCOL_VERSION, 3)
ldap.set_option(ldap.OPT_X_TLS_CACERTFILE, os.path.join(common.SSL_ROOT, 'ccscert.pem'))
ldap.set_option(ldap.OPT_X_TLS_REQUIRE_CERT, ldap.OPT_X_TLS_DEMAND)

def full_name(name):
	return name + '.ccs.ucsb.edu'

servers = map(full_name, ('zweihander', 'wireless'))

def finger_connection(server = servers[0]):
	for info in socket.getaddrinfo(server, 'finger', socket.AF_INET, socket.SOCK_STREAM):
		family, type, protocol, name, address = info

		try:
			finger = socket.socket(family, type, protocol)
		except socket.error, exception:
			finger = None

			continue

		finger.settimeout(0.5)

		try:
			finger.connect(address)
		except socket.error, exception:
			finger.close()

			finger = None

			continue

		break

	if finger is None:
		raise exception

	finger.settimeout(10.0)

	return finger.makefile('r+b')

scheme = '[A-Za-z][-+.0-9A-Za-z]*'
unreserved = '[-._~0-9A-Za-z]'
# XXX: extension to allow Latin characters in URIs
latin = u'[ÀÁÂÃÄÅÆÇÈÉÊËËÌÍÎÏÐÑÒÓÔÕÖØUÚÛÜÝÞßàáâãäåæçèéêëìíïðñòóô°öùúûüý]'
pct_encoded = '(?:%[0-9A-Fa-f]{2}|' + latin + ')'
sub_delims = '[!$&\'()*+,;=]'
userinfo = '(?:%s|%s|%s|:)*' % (unreserved, pct_encoded, sub_delims)
h16 = '[0-9A-Fa-f]{1,4}'
dec_octet = '(?:[0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])'
ipv4address = r'\.'.join((dec_octet,) * 4)
ls32 = '(?:%s:%s|%s)' % (h16, h16, ipv4address)
ipv6address = '(?:(?:%s){6}%s)' % (h16, ls32)
ipvfuture = 'v[0-9A-Fa-f]+.(?:%s|%s|:)+' % (unreserved, sub_delims)
ip_literal = r'\[(?:%s|%s)\]' % (ipv6address, ipvfuture)
reg_name = '(?:%s|%s|%s)*' % (unreserved, pct_encoded, sub_delims)
host = '(?:%s|%s|%s)' % (ip_literal, ipv4address, reg_name)
port = '[0-9]*'
authority = '(?:%s@)?%s(?::%s)?' % (userinfo, host, port)
pchar = '(?:%s|%s|%s)' % (unreserved, pct_encoded, sub_delims)
segment = pchar + '*'
path_abempty = '(?:/%s)*' % segment
segment_nz = pchar + '+'
path_absolute = '/(?:%s(?:/%s)*)?' % (segment_nz, segment)
path_rootless = '%s(?:/%s)*' % (segment_nz, segment)
hier_part = '(?://%s%s|%s|%s)' % (authority, path_abempty, path_absolute, path_rootless)
query = r'(?:%s|/|\?)*' % pchar
fragment = r'(?:%s|/|\?)*' % pchar
uri = re.compile('%s:%s(?:%s)?(?:#%s)?' % (scheme, hier_part, query, fragment))

del scheme, unreserved, latin, pct_encoded, sub_delims, userinfo, h16, dec_octet, ipv4address, ls32, ipv6address, ipvfuture, ip_literal, reg_name, host, port, authority, pchar, segment, path_abempty, segment_nz, path_absolute, path_rootless, hier_part, query, fragment

def htmlify(text):
	items = ''

	for item in uri.split(text):
		if uri.match(item) is not None:
			items += '<a href="' + cgi.escape(item, True) + '">' + cgi.escape(item) + '</a>'
		else:
			items += cgi.escape(item)

	return items

ldap_uri = ' '.join(map(lambda server: 'ldaps://' + server, servers))
base = 'dc=ccs,dc=ucsb,dc=edu'

def ldap_connection(user = None, password = None):
	connection = ldap.initialize(ldap_uri)

	connection.simple_bind_s('uid=%s,ou=People,%s' % (user, base) if user is not None else '', password if password is not None else '')

	return connection

is_wireless = socket.gethostname() == 'wireless.ccs.ucsb.edu'

def request_mail(request):
	if not is_wireless:
		mail_admins('CCS CS Account Request from ' + request.full_name, 'The supposed CCS CS student going by the name %s wants the account %s.\n\n%s/account/requests' % (request.full_name, request.name, settings.CCSCSLAB_CALLBACK_SECURE))

def timezone(when, timezone = pytz.timezone(settings.CCSCSLAB_TIMEZONE)):
	return (pytz.UTC.localize(when) if when.tzinfo is None else when).astimezone(timezone)

def unescape(html):
	return unicode(BeautifulStoneSoup(html, convertEntities = BeautifulStoneSoup.ALL_ENTITIES))