#!/usr/bin/python
#
# File:   create_user.py
#
# Create user.  Prompt for groups and ExternalAuthMap

import os, sys, string, re
import datetime
from getpass import getpass
import json
import readline

sys.path.append(os.path.abspath('.'))
os.environ['DJANGO_SETTINGS_MODULE'] = 'lms.envs.dev'

try:
    from lms.envs.dev import *
except Exception as err:
    print "Run this script from the top-level mitx directory (mitx_all/mitx), not a subdirectory."
    sys.exit(-1)

from student.models import UserProfile, Registration
from external_auth.models import ExternalAuthMap
from django.contrib.auth.models import User, Group
from random import choice

class MyCompleter(object):  # Custom completer

    def __init__(self, options):
        self.options = sorted(options)

    def complete(self, text, state):
        if state == 0:  # on first trigger, build possible matches
            if text:  # cache matches (entries that start with entered text)
                self.matches = [s for s in self.options 
                                    if s and s.startswith(text)]
            else:  # no text entered, all matches possible
                self.matches = self.options[:]

        # return match indexed by state
        try: 
            return self.matches[state]
        except IndexError:
            return None

def GenPasswd(length=8, chars=string.letters + string.digits):
    return ''.join([choice(chars) for i in range(length)])

#-----------------------------------------------------------------------------
# main

while True:
    uname = raw_input('username: ')
    if User.objects.filter(username=uname):
        print "username %s already taken" % uname
    else:
        break

make_eamap = False
if raw_input('Create MIT ExternalAuth? [n] ').lower()=='y':
    email = '%s@MIT.EDU' % uname
    if not email.endswith('@MIT.EDU'):
        print "Failed - email must be @MIT.EDU"
        sys.exit(-1)
    mit_domain = 'ssl:MIT'
    if ExternalAuthMap.objects.filter(external_id = email, external_domain = mit_domain):
        print "Failed - email %s already exists as external_id" % email
        sys.exit(-1)
    make_eamap = True
    password = GenPasswd(12)
    
    # get name from kerberos
    kname = os.popen("finger %s | grep 'name:'" % email).read().strip().split('name: ')[1].strip()
    name = raw_input('Full name: [%s] ' % kname).strip()
    if name=='':
        name = kname
    print "name = %s" % name
else:
    while True:
        password = getpass()
        password2 = getpass()
        if password == password2:
            break
        print "Oops, passwords do not match, please retry"

    while True:
        email = raw_input('email: ')
        if User.objects.filter(email=email):
            print "email %s already taken" % email
        else:
            break
        
    name = raw_input('Full name: ')

        
user = User(username=uname, email=email, is_active=True)
user.set_password(password)
try:
    user.save()
except IntegrityError:
    print "Oops, failed to create user %s, IntegrityError" % user
    raise
    
r = Registration()
r.register(user)

up = UserProfile(user=user)
up.name = name
up.save()

if make_eamap:
    credentials = "/C=US/ST=Massachusetts/O=Massachusetts Institute of Technology/OU=Client CA v1/CN=%s/emailAddress=%s" % (name,email)
    eamap = ExternalAuthMap(external_id = email,
                            external_email = email,
                            external_domain = mit_domain,
                            external_name = name,
                            internal_password = password,
                            external_credentials = json.dumps(credentials),
        )
    eamap.user = user
    eamap.dtsignup = datetime.datetime.now()
    eamap.save()

print "User %s created successfully!" % user

if not raw_input('Add user %s to any groups? [n] ' % user).lower()=='y':
    sys.exit(0)

print "Here are the groups available:"

groups = [str(g.name) for g in Group.objects.all()]
print groups

completer = MyCompleter(groups)
readline.set_completer(completer.complete)
readline.parse_and_bind('tab: complete')

while True:
    gname = raw_input("Add group (tab to autocomplete, empty line to end): ")
    if not gname:
        break
    if not gname in groups:
        print "Unknown group %s" % gname
        continue
    g = Group.objects.get(name=gname)
    user.groups.add(g)
    print "Added %s to group %s" % (user,g)

print "Done!"