# coding: utf-8
# Author: Guanghongwei
# Email: ibuler@qq.com

import time
import os
import hashlib
import random
import subprocess
import ldap
from ldap import modlist
from Crypto.PublicKey import RSA
import crypt
from django.http import HttpResponseRedirect

from django.shortcuts import render_to_response
from django.core.exceptions import ObjectDoesNotExist

from juser.models import UserGroup, User
from connect import PyCrypt, KEY
from connect import BASE_DIR
from connect import CONF
from django.core.paginator import Paginator, EmptyPage, InvalidPage

CRYPTOR = PyCrypt(KEY)
LDAP_ENABLE = CONF.getint('ldap', 'ldap_enable')
if LDAP_ENABLE:
    LDAP_HOST_URL = CONF.get('ldap', 'host_url')
    LDAP_BASE_DN = CONF.get('ldap', 'base_dn')
    LDAP_ROOT_DN = CONF.get('ldap', 'root_dn')
    LDAP_ROOT_PW = CONF.get('ldap', 'root_pw')


def md5_crypt(string):
    return hashlib.new("md5", string).hexdigest()


def gen_rand_pwd(num):
    """生成随机密码"""
    seed = "1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
    salt_list = []
    for i in range(num):
        salt_list.append(random.choice(seed))
    salt = ''.join(salt_list)
    return salt


def bash(cmd):
    """执行bash命令"""
    return subprocess.call(cmd, shell=True)


def is_dir(dir_name, mode=0755):
    if not os.path.isdir(dir_name):
        os.makedirs(dir_name)
    os.chmod(dir_name, mode)


class AddError(Exception):
    pass


class LDAPMgmt():
    def __init__(self,
                 host_url,
                 base_dn,
                 root_cn,
                 root_pw):
        self.ldap_host = host_url
        self.ldap_base_dn = base_dn
        self.conn = ldap.initialize(host_url)
        self.conn.set_option(ldap.OPT_REFERRALS, 0)
        self.conn.protocol_version = ldap.VERSION3
        self.conn.simple_bind_s(root_cn, root_pw)

    def list(self, filter, scope=ldap.SCOPE_SUBTREE, attr=None):
        result = {}
        try:
            ldap_result = self.conn.search_s(self.ldap_base_dn, scope, filter, attr)
            for entry in ldap_result:
                name, data = entry
                for k, v in data.items():
                    print '%s: %s' % (k, v)
                    result[k] = v
            return result
        except ldap.LDAPError, e:
            print e

    def add(self, dn, attrs):
        try:
            ldif = modlist.addModlist(attrs)
            self.conn.add_s(dn, ldif)
        except ldap.LDAPError, e:
            print e

    def modify(self, dn, attrs):
        try:
            attr_s = []
            for k, v in attrs.items():
                attr_s.append((2, k, v))
            self.conn.modify_s(dn, attr_s)
        except ldap.LDAPError, e:
            print e

    def delete(self, dn):
        try:
            self.conn.delete_s(dn)
        except ldap.LDAPError, e:
            print e


def gen_sha512(salt, password):
    return crypt.crypt(password, '$6$%s$' % salt)


def group_add(request):
    error = ''
    msg = ''
    header_title, path1, path2 = '添加属组 | Add Group', 'juser', 'group_add'

    if request.method == 'POST':
        group_name = request.POST.get('group_name', None)
        comment = request.POST.get('comment', None)

        try:
            if not group_name:
                error = u'组名不能为空'
                raise AddError

            group = UserGroup.objects.filter(name=group_name)
            if group:
                error = u'组 %s 已存在' % group_name
                raise AddError

            group = UserGroup(name=group_name, comment=comment)
            group.save()
        except AddError:
            pass

        except TypeError:
            error = u'保存用户失败'

        else:
            msg = u'添加组 %s 成功' % group_name

    return render_to_response('juser/group_add.html', locals())


def group_list(request):
    header_title, path1, path2 = '查看属组 | Add Group', 'juser', 'group_list'
    groups = UserGroup.objects.all()
    return render_to_response('juser/group_list.html', locals())


def user_list(request):
    user_role = {'SU': u'超级管理员', 'GA': u'组管理员', 'CU': u'普通用户'}
    header_title, path1, path2 = '查看用户 | Show User', 'juser', 'user_list'
    users = contact_list = User.objects.all().order_by('id')
    p = paginator = Paginator(contact_list, 10)

    try:
        page = int(request.GET.get('page', '1'))
    except ValueError:
        page = 1

    try:
        contacts = paginator.page(page)
    except (EmptyPage, InvalidPage):
        contacts = paginator.page(paginator.num_pages)
    return render_to_response('juser/user_list.html', locals())


def user_detail(request):
    username = request.GET.get('username', None)
    if not username:
        return HttpResponseRedirect('/')
    user = User.objects.get(username=username)
    return render_to_response('juser/user_detail.html', locals(), context_instance=RequestContext(request))


def db_add_user(**kwargs):
    groups_post = kwargs.pop('groups')
    user = User(**kwargs)
    group_select = []
    for group_id in groups_post:
        group = UserGroup.objects.filter(id=group_id)
        group_select.extend(group)
    user.save()
    user.user_group = group_select


def db_del_user(username):
    try:
        user = User.objects.get(username=username)
        user.delete()
    except ObjectDoesNotExist:
        pass


def gen_ssh_key(username, password=None, length=2048):
    private_key_dir = os.path.join(BASE_DIR, 'keys/jumpserver/')
    private_key_file = os.path.join(private_key_dir, username)
    public_key_dir = '/home/%s/.ssh/' % username
    public_key_file = os.path.join(public_key_dir, 'authorized_keys')
    is_dir(private_key_dir)
    is_dir(public_key_dir, mode=0700)

    key = RSA.generate(length)
    with open(private_key_file, 'w') as pri_f:
        pri_f.write(key.exportKey('PEM', password))
    os.chmod(private_key_file, 0600)

    pub_key = key.publickey()
    with open(public_key_file, 'w') as pub_f:
        pub_f.write(pub_key.exportKey('OpenSSH'))
    os.chmod(public_key_file, 0600)
    bash('chown %s:%s %s' % (username, username, public_key_file))


def server_add_user(username, password, ssh_key_pwd1):
    bash('useradd %s; echo %s | passwd --stdin %s' % (username, password, username))
    gen_ssh_key(username, ssh_key_pwd1)


def server_del_user(username):
    bash('userdel -r %s' % username)


def ldap_add_user(username, ldap_pwd):
    user_dn = "uid=%s,ou=People,%s" % (username, LDAP_BASE_DN)
    password_sha512 = gen_sha512(gen_rand_pwd(6), ldap_pwd)
    user = User.objects.get(username=username)

    user_attr = {'uid': [str(username)],
                 'cn': [str(username)],
                 'objectClass': ['account', 'posixAccount', 'top', 'shadowAccount'],
                 'userPassword': ['{crypt}%s' % password_sha512],
                 'shadowLastChange': ['16328'],
                 'shadowMin': ['0'],
                 'shadowMax': ['99999'],
                 'shadowWarning': ['7'],
                 'loginShell': ['/bin/bash'],
                 'uidNumber': [str(user.id)],
                 'gidNumber': [str(user.id)],
                 'homeDirectory': [str('/home/%s' % username)]}

    group_dn = "cn=%s,ou=Group,%s" % (username, LDAP_BASE_DN)
    group_attr = {'objectClass': ['posixGroup', 'top'],
                  'cn': [str(username)],
                  'userPassword': ['{crypt}x'],
                  'gidNumber': [str(user.id)]}

    sudo_dn = 'cn=%s,ou=Sudoers,%s' % (username, LDAP_BASE_DN)
    sudo_attr = {'objectClass': ['top', 'sudoRole'],
                 'cn': ['%s' % str(username)],
                 'sudoCommand': ['/bin/pwd'],
                 'sudoHost': ['192.168.1.1'],
                 'sudoOption': ['!authenticate'],
                 'sudoRunAsUser': ['root'],
                 'sudoUser': ['%s' % str(username)]}

    ldap_conn = LDAPMgmt(LDAP_HOST_URL, LDAP_BASE_DN, LDAP_ROOT_DN, LDAP_ROOT_PW)

    ldap_conn.add(user_dn, user_attr)
    ldap_conn.add(group_dn, group_attr)
    ldap_conn.add(sudo_dn, sudo_attr)


def ldap_del_user(username):
    user_dn = "uid=%s,ou=People,%s" % (username, LDAP_BASE_DN)
    group_dn = "cn=%s,ou=Group,%s" % (username, LDAP_BASE_DN)
    sudo_dn = 'cn=%s,ou=Sudoers,%s' % (username, LDAP_BASE_DN)

    ldap_conn = LDAPMgmt()
    ldap_conn.delete(user_dn)
    ldap_conn.delete(group_dn)
    ldap_conn.delete(sudo_dn)


def user_add(request):
    error = ''
    msg = ''
    header_title, path1, path2 = '添加用户 | Add User', 'juser', 'user_add'
    user_role = {'SU': u'超级管理员', 'GA': u'组管理员', 'CU': u'普通用户'}
    all_group = UserGroup.objects.all()
    if request.method == 'POST':
        username = request.POST.get('username', None)
        password = request.POST.get('password', None)
        name = request.POST.get('name', None)
        email = request.POST.get('email', '')
        groups = request.POST.getlist('groups', None)
        groups_str = ' '.join(groups)
        role_post = request.POST.get('role', None)
        ssh_pwd = request.POST.get('ssh_pwd', None)
        ssh_key_pwd1 = request.POST.get('ssh_key_pwd1', None)
        is_active = request.POST.get('is_active', '1')
        ldap_pwd = gen_rand_pwd(16)

        try:
            if None in [username, password, ssh_key_pwd1, name, groups, role_post, is_active]:
                error = u'带*内容不能为空'
                raise AddError
            user = User.objects.filter(username=username)
            if user:
                error = u'用户 %s 已存在' % username
                raise AddError

        except AddError:
            pass
        else:
            time_now = time.time()
            try:
                db_add_user(username=username,
                            password=md5_crypt(password),
                            name=name, email=email,
                            groups=groups, role=role_post,
                            ssh_pwd=CRYPTOR.encrypt(ssh_pwd),
                            ssh_key_pwd1=CRYPTOR.encrypt(ssh_key_pwd1),
                            ldap_pwd=CRYPTOR.encrypt(ldap_pwd),
                            is_active=is_active,
                            date_joined=time_now)

                server_add_user(username, password, ssh_key_pwd1)
                if LDAP_ENABLE:
                    ldap_add_user(username, ldap_pwd)
                msg = u'添加用户 %s 成功！' % username
                # locals = lambda: {}

            except Exception, e:
                error = u'添加用户 %s 失败 %s ' % (username, e)
                try:
                    db_del_user(username)
                    server_del_user(username)
                    if LDAP_ENABLE:
                        ldap_del_user(username)
                except Exception:
                    pass

    return render_to_response('juser/user_add.html', locals())