# -*- coding: utf-8 -*-

import os
import sys
import ldap
import crypt
import random
import string
import getpass
from yunohost import YunoHostError, win_msg, colorize, validate, get_required_args

def user_list(args, connections):
    """
    List YunoHost users from LDAP

    Keyword argument:
        args -- Dictionnary of values (can be empty)
        connections -- LDAP connection

    Returns:
        Dict
    """
    yldap = connections['ldap']
    user_attrs = ['uid', 'mail', 'cn', 'mailalias']
    attrs = []
    result_dict = {}
    if args['offset']: offset = int(args['offset'])
    else: offset = 0
    if args['limit']: limit = int(args['limit'])
    else: limit = 1000
    if args['filter']: filter = args['filter']
    else: filter = 'uid=*'
    if args['fields']:
        for attr in args['fields']:
            if attr in user_attrs:
                attrs.append(attr)
                continue
            else:
                raise YunoHostError(22, _("Invalid field : ") + attr)        
    else:
        attrs = user_attrs

    result = yldap.search('ou=users,dc=yunohost,dc=org', filter, attrs)
    
    if result and len(result) > (0 + offset) and limit > 0:
        i = 0 + offset
        for user in result[i:]:
            if i < limit:
                entry = {
                    'Username': user['uid'],
                    'Fullname': user['cn'],
                    'Mail': user['mail'][0]
                }
                if len(user['mail']) > 1:
                    entry['Mail Forward'] = user['mail'][1:]
                if 'mailalias' in user:
                    entry['Mail Aliases'] = user['mailalias']
                    
                result_dict[str(i)] = entry 
                i += 1
    else:
        raise YunoHostError(167, _("No user found"))

    return result_dict


def user_create(args, connections):
    """
    Add user to LDAP

    Keyword argument:
        args -- Dictionnary of values (can be empty)
        connections -- LDAP connections

    Returns:
        Dict
    """
    yldap = connections['ldap']
    args = get_required_args(args, {
        'username': _('Username'), 
        'mail': _('Mail address'), 
        'firstname': _('Firstname'), 
        'lastname': _('Lastname'), 
        'password': _('Password')
    }, True)

    # Validate password length
    if len(args['password']) < 4:
        raise YunoHostError(22, _("Password is too short"))

    # Validate other values TODO: validate all values
    validate({
        args['username']    : r'^[a-z0-9_]+$', 
        args['mail']        : r'^[\w.-]+@[\w.-]+\.[a-zA-Z]{2,6}$',
    })

    yldap.validate_uniqueness({
        'uid'       : args['username'],
        'mail'      : args['mail'],
        'mailalias' : args['mail']
    })

    # Check if unix user already exists (doesn't work)
    #if not os.system("getent passwd " + args['username']):
    #    raise YunoHostError(17, _("Username not available"))

    #TODO: check if mail belongs to a domain

    # Get random UID/GID
    uid_check = gid_check = 0
    while uid_check == 0 and gid_check == 0:
        uid = str(random.randint(200, 99999))
        uid_check = os.system("getent passwd " + uid)
        gid_check = os.system("getent group " + uid)

    # Adapt values for LDAP
    fullname = args['firstname'] + ' ' + args['lastname']
    rdn = 'uid=' + args['username'] + ',ou=users'
    char_set = string.ascii_uppercase + string.digits
    salt = ''.join(random.sample(char_set,8))
    salt = '$1$' + salt + '$'
    pwd = '{CRYPT}' + crypt.crypt(str(args['password']), salt)
    attr_dict = {
        'objectClass'   : ['mailAccount', 'inetOrgPerson', 'posixAccount'],
        'givenName'     : args['firstname'],
        'sn'            : args['lastname'],
        'displayName'   : fullname,
        'cn'            : fullname,
        'uid'           : args['username'],
        'mail'          : args['mail'],
        'userPassword'  : pwd,
        'gidNumber'     : uid,
        'uidNumber'     : uid,
        'homeDirectory' : '/home/' + args['username'],
        'loginShell'    : '/bin/false'
    }

    if yldap.add(rdn, attr_dict):
        # Create user /home directory by switching user
        os.system("su - " + args['username'] + " -c ''")
        #TODO: Send a welcome mail to user
        win_msg(_("User successfully created"))
        return { _("Fullname") : fullname, _("Username") : args['username'], _("Mail") : args['mail'] }
    else:
        raise YunoHostError(169, _("An error occured during user creation"))


def user_delete(args, connections):
    """
    Remove user from LDAP

    Keyword argument:
        args -- Dictionnary of values (can be empty)
        connections -- LDAP connection

    Returns:
        Dict
    """
    yldap = connections['ldap']
    result = { 'Users' : [] }

    args = get_required_args(args, { 'users' : _('User to delete') })
    if not isinstance(args['users'], list):
        args['users'] = [ args['users'] ]

    for user in args['users']:
        validate({ user : r'^[a-z0-9_]+$' })
        if yldap.remove('uid=' + user+ ',ou=users'):
            if args['purge']:
                os.system('rm -rf /home/' + user)
            result['Users'].append(user)
            continue
        else:
            raise YunoHostError(169, _("An error occured during user deletion"))

    win_msg(_("User(s) successfully deleted"))
    return result 
            

def user_update(args, connections):
    """
    Update user informations

    Keyword argument:
        args -- Dictionnary of values
        connections -- LDAP connection

    Returns:
        Dict
    """
    yldap = connections['ldap']
    validate({ args['user'] : r'^[a-z0-9_]+$' })
    attrs_to_fetch = ['givenName', 'sn', 'mail', 'mailAlias']
    new_attr_dict = {}

    # Populate user informations
    result = yldap.search(base='ou=users,dc=yunohost,dc=org', filter='uid=' + args['user'], attrs=attrs_to_fetch)
    if not result:
        raise YunoHostError(167, _("No user found"))
    user = result[0]

    # Get modifications from arguments
    if args['firstname']:
        new_attr_dict['givenName'] = args['firstname'] # TODO: Validate
        new_attr_dict['cn'] = new_attr_dict['displayName'] = args['firstname'] + ' ' + user['sn'][0]

    if args['lastname']:
        new_attr_dict['sn'] = args['lastname'] # TODO: Validate
        new_attr_dict['cn'] = new_attr_dict['displayName'] = user['givenName'][0] + ' ' + args['lastname']

    if args['lastname'] and args['firstname']:
        new_attr_dict['cn'] = new_attr_dict['displayName'] = args['firstname'] + ' ' + args['lastname']

    if args['change_password']:
        char_set = string.ascii_uppercase + string.digits
        salt = ''.join(random.sample(char_set,8))
        salt = '$1$' + salt + '$'
        new_attr_dict['userPassword'] = '{CRYPT}' + crypt.crypt(str(args['change_password']), salt)

    if args['mail']:
        validate({ args['mail'] : r'^[\w.-]+@[\w.-]+\.[a-zA-Z]{2,6}$' })
        yldap.validate_uniqueness({
            'mail'      : args['mail'],
            'mailalias' : args['mail']
        })
        del user['mail'][0]
        new_attr_dict['mail'] = [args['mail']] + user['mail']

    if args['add_mailforward']:
        if not isinstance(args['add_mailforward'], list):
            args['add_mailforward'] = [ args['add_mailforward'] ]
        for mail in args['add_mailforward']:
            validate({ mail : r'^[\w.-]+@[\w.-]+\.[a-zA-Z]{2,6}$' })
            yldap.validate_uniqueness({
                'mail'      : mail,
                'mailalias' : mail
            })
            user['mail'].append(mail)
        new_attr_dict['mail'] = user['mail']

    if args['remove_mailforward']:
        if not isinstance(args['remove_mailforward'], list):
            args['remove_mailforward'] = [ args['remove_mailforward'] ]
        for mail in args['remove_mailforward']:
            if len(user['mail']) > 1 and mail in user['mail'][1:]:
                user['mail'].remove(mail)
            else:
                raise YunoHostError(22, _("Invalid mail forward : ") + mail) 
        new_attr_dict['mail'] = user['mail']

    if args['add_mailalias']:
        if not isinstance(args['add_mailalias'], list):
            args['add_mailalias'] = [ args['add_mailalias'] ]
        for mail in args['add_mailalias']:
            validate({ mail : r'^[\w.-]+@[\w.-]+\.[a-zA-Z]{2,6}$' })
            yldap.validate_uniqueness({
                'mail'      : mail,
                'mailalias' : mail
            })
            if 'mailalias' in user:
                user['mailalias'].append(mail)
            else:
                user['mailalias'] = [ mail ]
        new_attr_dict['mailalias'] = user['mailalias']

    if args['remove_mailalias']:
        if not isinstance(args['remove_mailalias'], list):
            args['remove_mailalias'] = [ args['remove_mailalias'] ]
        for mail in args['remove_mailalias']:
            if 'mailalias' in user and mail in user['mailalias']:
                user['mailalias'].remove(mail)
            else:
                raise YunoHostError(22, _("Invalid mail alias : ") + mail) 
        new_attr_dict['mailalias'] = user['mailalias']

    if yldap.update('uid=' + args['user'] + ',ou=users', new_attr_dict):
       win_msg(_("User successfully updated"))
       return user_info({ 'user' : args['user'], 'mail' : None }, connections)
    else:
       raise YunoHostError(169, _("An error occured during user update"))
    


def user_info(args, connections):
    """
    Fetch user informations from LDAP

    Keyword argument:
        args -- Dictionnary of values (can be empty)
        connections -- LDAP connection

    Returns:
        Dict
    """
    yldap = connections['ldap']
    user_attrs = ['cn', 'mail', 'uid', 'mailAlias']

    if args['mail']:
        validate({ args['mail'] : r'^[\w.-]+@[\w.-]+\.[a-zA-Z]{2,6}$' })
        filter = 'mail=' + args['mail']
    else:
        args = get_required_args(args, { 'user' : _("Username") })
        validate({ args['user'] : r'^[a-z0-9_]+$' })
        filter = 'uid=' + args['user']

    result = yldap.search('ou=users,dc=yunohost,dc=org', filter, user_attrs)
    user = result[0]
    result_dict = {
        'Username': user['uid'],
        'Fullname': user['cn'],
        'Mail': user['mail'][0]
    }

    if len(user['mail']) > 1:
        result_dict['Mail Forward'] = user['mail'][1:]

    if 'mailalias' in user:
        result_dict['Mail Aliases'] = user['mailalias']

    if result:
        return result_dict
    else:
        raise YunoHostError(167, _("No user found"))