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

"""

    rhodecode.controllers.admin.users

    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Users crud controller for pylons

    :created_on: Apr 4, 2010

    :author: marcink

    :copyright: (C) 2010-2012 Marcin Kuzminski <marcin@python-works.com>

    :license: GPLv3, see COPYING for more details.

"""

# This program is free software: you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation, either version 3 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import logging

import traceback

import formencode

from pylons import response

from formencode import htmlfill

from pylons import request, session, tmpl_context as c, url, config

from pylons.controllers.util import redirect

from pylons.i18n.translation import _

from rhodecode.lib.exceptions import DefaultUserException, \

    UserOwnsReposException

from rhodecode.lib import helpers as h

from rhodecode.lib.auth import LoginRequired, HasPermissionAllDecorator, \

    AuthUser

from rhodecode.lib.base import BaseController, render

import rhodecode

from rhodecode.model.db import User, Permission, UserEmailMap

from rhodecode.model.forms import UserForm

from rhodecode.model.user import UserModel

from rhodecode.model.meta import Session

from rhodecode.lib.utils import action_logger

from rhodecode.lib.compat import json

log = logging.getLogger(__name__)

class UsersController(BaseController):

    """REST Controller styled on the Atom Publishing Protocol"""

    # To properly map this controller, ensure your config/routing.py

    # file has a resource setup:

    #     map.resource('user', 'users')

    @LoginRequired()

    @HasPermissionAllDecorator('hg.admin')

    def __before__(self):

        c.admin_user = session.get('admin_user')

        c.admin_username = session.get('admin_username')

        super(UsersController, self).__before__()

        c.available_permissions = config['available_permissions']

    def index(self, format='html'):

        """GET /users: All items in the collection"""

        # url('users')

        c.users_list = User.query().order_by(User.username).all()

        users_data = []

        total_records = len(c.users_list)

        _tmpl_lookup = rhodecode.CONFIG['pylons.app_globals'].mako_lookup

        template = _tmpl_lookup.get_template('data_table/_dt_elements.html')

        grav_tmpl = lambda user_email, size: (

                template.get_def("user_gravatar")

                .render(user_email, size, _=_, h=h, c=c))

        user_lnk = lambda user_id, username: (

                template.get_def("user_name")

                .render(user_id, username, _=_, h=h, c=c))

        user_actions = lambda user_id, username: (

                template.get_def("user_actions")

                .render(user_id, username, _=_, h=h, c=c))

        for user in c.users_list:

            users_data.append({

                "gravatar": grav_tmpl(user. email, 24),

                "raw_username": user.username,

                "username": user_lnk(user.user_id, user.username),

                "firstname": user.name,

                "lastname": user.lastname,

                "last_login": h.fmt_date(user.last_login),

                "active": h.bool2icon(user.active),

                "admin": h.bool2icon(user.admin),

                "ldap": h.bool2icon(bool(user.ldap_dn)),

                "action": user_actions(user.user_id, user.username),

            })

        c.data = json.dumps({

            "totalRecords": total_records,

            "startIndex": 0,

            "sort": None,

            "dir": "asc",

            "records": users_data

        })

        return render('admin/users/users.html')

    def create(self):

        """POST /users: Create a new item"""

        # url('users')

        user_model = UserModel()

        user_form = UserForm()()

        try:

            form_result = user_form.to_python(dict(request.POST))

            user_model.create(form_result)

            usr = form_result['username']

            action_logger(self.rhodecode_user, 'admin_created_user:%s' % usr,

                          None, self.ip_addr, self.sa)

            h.flash(_('created user %s') % usr,

                    category='success')

            Session().commit()

        except formencode.Invalid, errors:

            return htmlfill.render(

                render('admin/users/user_add.html'),

                defaults=errors.value,

                errors=errors.error_dict or {},

                prefix_error=False,

                encoding="UTF-8")

        except Exception:

            log.error(traceback.format_exc())

            h.flash(_('error occurred during creation of user %s') \

                    % request.POST.get('username'), category='error')

        return redirect(url('users'))

    def new(self, format='html'):

        """GET /users/new: Form to create a new item"""

        # url('new_user')

        return render('admin/users/user_add.html')

    def update(self, id):

        """PUT /users/id: Update an existing item"""

        # Forms posted to this method should contain a hidden field:

        #    <input type="hidden" name="_method" value="PUT" />

        # Or using helpers:

        #    h.form(url('update_user', id=ID),

        #           method='put')

        # url('user', id=ID)

        user_model = UserModel()

        c.user = user_model.get(id)

        c.perm_user = AuthUser(user_id=id)

        _form = UserForm(edit=True, old_data={'user_id': id,

                                              'email': c.user.email})()

        form_result = {}

        try:

            form_result = _form.to_python(dict(request.POST))

            user_model.update(id, form_result)

            usr = form_result['username']

            action_logger(self.rhodecode_user, 'admin_updated_user:%s' % usr,

                          None, self.ip_addr, self.sa)

            h.flash(_('User updated successfully'), category='success')

            Session().commit()

        except formencode.Invalid, errors:

            c.user_email_map = UserEmailMap.query()\

                            .filter(UserEmailMap.user == c.user).all()

            defaults = errors.value

            e = errors.error_dict or {}

            perm = Permission.get_by_key('hg.create.repository')

            defaults.update({'create_repo_perm': user_model.has_perm(id, perm)})

            defaults.update({'_method': 'put'})

            return htmlfill.render(

                render('admin/users/user_edit.html'),

                defaults=defaults,

                errors=e,

                prefix_error=False,

                encoding="UTF-8")

        except Exception:

            log.error(traceback.format_exc())

            h.flash(_('error occurred during update of user %s') \

                    % form_result.get('username'), category='error')

        return redirect(url('users'))

    def delete(self, id):

        """DELETE /users/id: Delete an existing item"""

        # Forms posted to this method should contain a hidden field:

        #    <input type="hidden" name="_method" value="DELETE" />

        # Or using helpers:

        #    h.form(url('delete_user', id=ID),

        #           method='delete')

        # url('user', id=ID)

        user_model = UserModel()

        try:

            user_model.delete(id)

            Session().commit()

            h.flash(_('successfully deleted user'), category='success')

        except (UserOwnsReposException, DefaultUserException), e:

            h.flash(e, category='warning')

        except Exception:

            log.error(traceback.format_exc())

            h.flash(_('An error occurred during deletion of user'),

                    category='error')

        return redirect(url('users'))

    def show(self, id, format='html'):

        """GET /users/id: Show a specific item"""

        # url('user', id=ID)

    def edit(self, id, format='html'):

        """GET /users/id/edit: Form to edit an existing item"""

        # url('edit_user', id=ID)

        c.user = User.get_or_404(id)

        if c.user.username == 'default':

            h.flash(_("You can't edit this user"), category='warning')

            return redirect(url('users'))

        c.perm_user = AuthUser(user_id=id)

        c.user.permissions = {}

        c.granted_permissions = UserModel().fill_perms(c.user)\

            .permissions['global']

        c.user_email_map = UserEmailMap.query()\

                        .filter(UserEmailMap.user == c.user).all()

        defaults = c.user.get_dict()

        perm = Permission.get_by_key('hg.create.repository')

        defaults.update({'create_repo_perm': UserModel().has_perm(id, perm)})

        return htmlfill.render(

            render('admin/users/user_edit.html'),

            defaults=defaults,

            encoding="UTF-8",

            force_defaults=False

        )

    def update_perm(self, id):

        """PUT /users_perm/id: Update an existing item"""

        # url('user_perm', id=ID, method='put')

        grant_perm = request.POST.get('create_repo_perm', False)

        user_model = UserModel()

        if grant_perm:

            perm = Permission.get_by_key('hg.create.none')

            user_model.revoke_perm(id, perm)

            perm = Permission.get_by_key('hg.create.repository')

            user_model.grant_perm(id, perm)

            h.flash(_("Granted 'repository create' permission to user"),

                    category='success')

            Session().commit()

        else:

            perm = Permission.get_by_key('hg.create.repository')

            user_model.revoke_perm(id, perm)

            perm = Permission.get_by_key('hg.create.none')

            user_model.grant_perm(id, perm)

            h.flash(_("Revoked 'repository create' permission to user"),

                    category='success')

            Session().commit()

        return redirect(url('edit_user', id=id))

    def add_email(self, id):

        """POST /user_emails:Add an existing item"""

        # url('user_emails', id=ID, method='put')

        #TODO: validation and form !!!

        email = request.POST.get('new_email')

        user_model = UserModel()

        try:

            user_model.add_extra_email(id, email)

            Session().commit()

            h.flash(_("Added email %s to user") % email, category='success')

        except formencode.Invalid, error:

            msg = error.error_dict['email']

            h.flash(msg, category='error')

        except Exception:

            log.error(traceback.format_exc())

            h.flash(_('An error occurred during email saving'),

                    category='error')

        return redirect(url('edit_user', id=id))

    def delete_email(self, id):

        """DELETE /user_emails_delete/id: Delete an existing item"""

        # url('user_emails_delete', id=ID, method='delete')

        user_model = UserModel()

        user_model.delete_extra_email(id, request.POST.get('del_email'))

        Session().commit()

        h.flash(_("Removed email from user"), category='success')

        return redirect(url('edit_user', id=id))

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

"""

    rhodecode.lib.utils

    ~~~~~~~~~~~~~~~~~~~

    Some simple helper functions

    :created_on: Jan 5, 2011

    :author: marcink

    :copyright: (C) 2011-2012 Marcin Kuzminski <marcin@python-works.com>

    :license: GPLv3, see COPYING for more details.

"""

# This program is free software: you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation, either version 3 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import re

from datetime import datetime

from pylons.i18n.translation import _, ungettext

from rhodecode.lib.vcs.utils.lazy import LazyProperty

def __get_lem():

    """

    Get language extension map based on what's inside pygments lexers

    """

    from pygments import lexers

    from string import lower

    from collections import defaultdict

    d = defaultdict(lambda: [])

    def __clean(s):

        s = s.lstrip('*')

        s = s.lstrip('.')

        if s.find('[') != -1:

            exts = []

            start, stop = s.find('['), s.find(']')

            for suffix in s[start + 1:stop]:

                exts.append(s[:s.find('[')] + suffix)

            return map(lower, exts)

        else:

            return map(lower, [s])

    for lx, t in sorted(lexers.LEXERS.items()):

        m = map(__clean, t[-2])

        if m:

            m = reduce(lambda x, y: x + y, m)

            for ext in m:

                desc = lx.replace('Lexer', '')

                d[ext].append(desc)

    return dict(d)

def str2bool(_str):

    """

    returs True/False value from given string, it tries to translate the

    string into boolean

    :param _str: string value to translate into boolean

    :rtype: boolean

    :returns: boolean from given string

    """

    if _str is None:

        return False

    if _str in (True, False):

        return _str

    _str = str(_str).strip().lower()

    return _str in ('t', 'true', 'y', 'yes', 'on', '1')

def convert_line_endings(line, mode):

    """

    Converts a given line  "line end" accordingly to given mode

    Available modes are::

        0 - Unix

        1 - Mac

        2 - DOS

    :param line: given line to convert

    :param mode: mode to convert to

    :rtype: str

    :return: converted line according to mode

    """

    from string import replace

    if mode == 0:

            line = replace(line, '\r\n', '\n')

            line = replace(line, '\r', '\n')

    elif mode == 1:

            line = replace(line, '\r\n', '\r')

            line = replace(line, '\n', '\r')

    elif mode == 2:

            line = re.sub("\r(?!\n)|(?<!\r)\n", "\r\n", line)

    return line

def detect_mode(line, default):

    """

    Detects line break for given line, if line break couldn't be found

    given default value is returned

    :param line: str line

    :param default: default

    :rtype: int

    :return: value of line end on of 0 - Unix, 1 - Mac, 2 - DOS

    """

    if line.endswith('\r\n'):

        return 2

    elif line.endswith('\n'):

        return 0

    elif line.endswith('\r'):

        return 1

    else:

        return default

def generate_api_key(username, salt=None):

    """

    Generates unique API key for given username, if salt is not given

    it'll be generated from some random string

    :param username: username as string

    :param salt: salt to hash generate KEY

    :rtype: str

    :returns: sha1 hash from username+salt

    """

    from tempfile import _RandomNameSequence

    import hashlib

    if salt is None:

        salt = _RandomNameSequence().next()

    return hashlib.sha1(username + salt).hexdigest()

def safe_unicode(str_, from_encoding=None):

    """

    safe unicode function. Does few trick to turn str_ into unicode

    In case of UnicodeDecode error we try to return it with encoding detected

    by chardet library if it fails fallback to unicode with errors replaced

    :param str_: string to decode

    :rtype: unicode

    :returns: unicode object

    """

    if isinstance(str_, unicode):

        return str_

    if not from_encoding:

        import rhodecode

        DEFAULT_ENCODING = rhodecode.CONFIG.get('default_encoding','utf8')

        from_encoding = DEFAULT_ENCODING

    try:

        return unicode(str_)

    except UnicodeDecodeError:

        pass

    try:

        return unicode(str_, from_encoding)

    except UnicodeDecodeError:

        pass

    try:

        import chardet

        encoding = chardet.detect(str_)['encoding']

        if encoding is None:

            raise Exception()

        return str_.decode(encoding)

    except (ImportError, UnicodeDecodeError, Exception):

        return unicode(str_, from_encoding, 'replace')

def safe_str(unicode_, to_encoding=None):

    """

    safe str function. Does few trick to turn unicode_ into string

    In case of UnicodeEncodeError we try to return it with encoding detected

    by chardet library if it fails fallback to string with errors replaced

    :param unicode_: unicode to encode

    :rtype: str

    :returns: str object

    """

    # if it's not basestr cast to str

    if not isinstance(unicode_, basestring):

        return str(unicode_)

    if isinstance(unicode_, str):

        return unicode_

    if not to_encoding:

        import rhodecode

        DEFAULT_ENCODING = rhodecode.CONFIG.get('default_encoding','utf8')

        to_encoding = DEFAULT_ENCODING

    try:

        return unicode_.encode(to_encoding)

    except UnicodeEncodeError:

        pass

    try:

        import chardet

        encoding = chardet.detect(unicode_)['encoding']

        if encoding is None:

            raise UnicodeEncodeError()

        return unicode_.encode(encoding)

    except (ImportError, UnicodeEncodeError):

        return unicode_.encode(to_encoding, 'replace')

    return safe_str

def engine_from_config(configuration, prefix='sqlalchemy.', **kwargs):

    """

    Custom engine_from_config functions that makes sure we use NullPool for

    file based sqlite databases. This prevents errors on sqlite. This only

    applies to sqlalchemy versions < 0.7.0

    """

    import sqlalchemy

    from sqlalchemy import engine_from_config as efc

    import logging

    if int(sqlalchemy.__version__.split('.')[1]) < 7:

        # This solution should work for sqlalchemy < 0.7.0, and should use

        # proxy=TimerProxy() for execution time profiling

        from sqlalchemy.pool import NullPool

        url = configuration[prefix + 'url']

        if url.startswith('sqlite'):

            kwargs.update({'poolclass': NullPool})

        return efc(configuration, prefix, **kwargs)

    else:

        import time

        from sqlalchemy import event

        from sqlalchemy.engine import Engine

        log = logging.getLogger('sqlalchemy.engine')

        BLACK, RED, GREEN, YELLOW, BLUE, MAGENTA, CYAN, WHITE = xrange(30, 38)

        engine = efc(configuration, prefix, **kwargs)

        def color_sql(sql):

            COLOR_SEQ = "\033[1;%dm"

            COLOR_SQL = YELLOW

            normal = '\x1b[0m'

            return ''.join([COLOR_SEQ % COLOR_SQL, sql, normal])

        if configuration['debug']:

            #attach events only for debug configuration

            def before_cursor_execute(conn, cursor, statement,

                                    parameters, context, executemany):

                context._query_start_time = time.time()

                log.info(color_sql(">>>>> STARTING QUERY >>>>>"))

            def after_cursor_execute(conn, cursor, statement,

                                    parameters, context, executemany):

                total = time.time() - context._query_start_time

                log.info(color_sql("<<<<< TOTAL TIME: %f <<<<<" % total))

            event.listen(engine, "before_cursor_execute",

                         before_cursor_execute)

            event.listen(engine, "after_cursor_execute",

                         after_cursor_execute)

    return engine

def age(prevdate):

    """

    turns a datetime into an age string.

    :param prevdate: datetime object

    :rtype: unicode

    :returns: unicode words describing age

    """

    order = ['year', 'month', 'day', 'hour', 'minute', 'second']

    deltas = {}

    # Get date parts deltas

    now = datetime.now()

    for part in order:

        deltas[part] = getattr(now, part) - getattr(prevdate, part)

    # Fix negative offsets (there is 1 second between 10:59:59 and 11:00:00,

    # not 1 hour, -59 minutes and -59 seconds)

    for num, length in [(5, 60), (4, 60), (3, 24)]:  # seconds, minutes, hours

        part = order[num]

        carry_part = order[num - 1]

        if deltas[part] < 0:

            deltas[part] += length

            deltas[carry_part] -= 1

    # Same thing for days except that the increment depends on the (variable)

    # number of days in the month

    month_lengths = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]

    if deltas['day'] < 0:

        if prevdate.month == 2 and (prevdate.year % 4 == 0 and

            (prevdate.year % 100 != 0 or prevdate.year % 400 == 0)):

            deltas['day'] += 29

        else:

            deltas['day'] += month_lengths[prevdate.month - 1]

        deltas['month'] -= 1

    if deltas['month'] < 0:

        deltas['month'] += 12

        deltas['year'] -= 1

    # Format the result

    fmt_funcs = {

        'year': lambda d: ungettext(u'%d year', '%d years', d) % d,

        'month': lambda d: ungettext(u'%d month', '%d months', d) % d,

        'day': lambda d: ungettext(u'%d day', '%d days', d) % d,

        'hour': lambda d: ungettext(u'%d hour', '%d hours', d) % d,

        'minute': lambda d: ungettext(u'%d minute', '%d minutes', d) % d,

        'second': lambda d: ungettext(u'%d second', '%d seconds', d) % d,

    }

    for i, part in enumerate(order):

        value = deltas[part]

        if value == 0:

            continue

        if i < 5:

            sub_part = order[i + 1]

            sub_value = deltas[sub_part]

        else:

            sub_value = 0

        if sub_value == 0:

            return _(u'%s ago') % fmt_funcs[part](value)

        return _(u'%s and %s ago') % (fmt_funcs[part](value),

            fmt_funcs[sub_part](sub_value))

    return _(u'just now')

def uri_filter(uri):

    """

    Removes user:password from given url string

    :param uri:

    :rtype: unicode

    :returns: filtered list of strings

    """

    if not uri:

        return ''

    proto = ''

    for pat in ('https://', 'http://'):

        if uri.startswith(pat):

            uri = uri[len(pat):]

            proto = pat

            break

    # remove passwords and username

    uri = uri[uri.find('@') + 1:]

    # get the port

    cred_pos = uri.find(':')

    if cred_pos == -1:

        host, port = uri, None

    else:

        host, port = uri[:cred_pos], uri[cred_pos + 1:]

    return filter(None, [proto, host, port])

def credentials_filter(uri):

    """

    Returns a url with removed credentials

    :param uri:

    """

    uri = uri_filter(uri)

    #check if we have port

    if len(uri) > 2 and uri[2]:

        uri[2] = ':' + uri[2]

    return ''.join(uri)

def get_changeset_safe(repo, rev):

    """

    Safe version of get_changeset if this changeset doesn't exists for a

    repo it returns a Dummy one instead

    :param repo:

    :param rev:

    """

    from rhodecode.lib.vcs.backends.base import BaseRepository

    from rhodecode.lib.vcs.exceptions import RepositoryError

    from rhodecode.lib.vcs.backends.base import EmptyChangeset

    if not isinstance(repo, BaseRepository):

        raise Exception('You must pass an Repository '

                        'object as first argument got %s', type(repo))

    try:

        cs = repo.get_changeset(rev)

    except RepositoryError:

        cs = EmptyChangeset(requested_revision=rev)

    return cs

MENTIONS_REGEX = r'(?:^@|\s@)([a-zA-Z0-9]{1}[a-zA-Z0-9\-\_\.]+)(?:\s{1})'

def extract_mentioned_users(s):

    """

    Returns unique usernames from given string s that have @mention

    :param s: string to get mentions

    """

    usrs = set()

    for username in re.findall(MENTIONS_REGEX, s):

        usrs.add(username)

    return sorted(list(usrs), key=lambda k: k.lower())

class AttributeDict(dict):

    def __getattr__(self, attr):

        return self.get(attr, None)

    __setattr__ = dict.__setitem__

    __delattr__ = dict.__delitem__

    ownerAC.formatResult = function (oResultData, sQuery, sResultMatch) {

		    var org_sQuery = sQuery;

		    if(this.dataSource.mentionQuery != null){

		    	sQuery = this.dataSource.mentionQuery;		    	

		    }

            var query = sQuery.toLowerCase();

            var _gravatar = function(res, em, group){

            	if (group !== undefined){

            		em = '/images/icons/group.png'

            	}

            	tmpl = '<div class="ac-container-wrap"><img class="perm-gravatar-ac" src="{0}"/>{1}</div>'

            	return tmpl.format(em,res)

            }

            if (oResultData.nname != undefined) {

                var fname = oResultData.fname || "";

                var lname = oResultData.lname || "";

                var nname = oResultData.nname;

                // Guard against null value

                var fnameMatchIndex = fname.toLowerCase().indexOf(query),

                    lnameMatchIndex = lname.toLowerCase().indexOf(query),

                    nnameMatchIndex = nname.toLowerCase().indexOf(query),

                    displayfname, displaylname, displaynname;

                if (fnameMatchIndex > -1) {

                    displayfname = highlightMatch(fname, query, fnameMatchIndex);

                } else {

                    displayfname = fname;

                }

                if (lnameMatchIndex > -1) {

                    displaylname = highlightMatch(lname, query, lnameMatchIndex);

                } else {

                    displaylname = lname;

                }

                if (nnameMatchIndex > -1) {

                    displaynname = "(" + highlightMatch(nname, query, nnameMatchIndex) + ")";

                } else {

                    displaynname = nname ? "(" + nname + ")" : "";

                }

                return _gravatar(displayfname + " " + displaylname + " " + displaynname, oResultData.gravatar_lnk);

            } else {

                return '';

            }

        };

    if(ownerAC.itemSelectEvent){

    	ownerAC.itemSelectEvent.subscribe(function (sType, aArgs) {

            var myAC = aArgs[0]; // reference back to the AC instance

            var elLI = aArgs[1]; // reference to the selected LI element

            var oData = aArgs[2]; // object literal of selected item's result data

            //fill the autocomplete with value

            if (oData.nname != undefined) {

                //users

            	//Replace the mention name with replaced

            	var re = new RegExp();

            	var org = myAC.getInputEl().value;

            	var chunks = myAC.dataSource.chunks

            	// replace middle chunk(the search term) with actuall  match

            	chunks[1] = chunks[1].replace('@'+myAC.dataSource.mentionQuery,

            								  '@'+oData.nname+' ');

                myAC.getInputEl().value = chunks.join('')

                YUD.get(myAC.getInputEl()).focus(); // Y U NO WORK !?

            } else {

                //groups

                myAC.getInputEl().value = oData.grname;

                YUD.get('perm_new_member_type').value = 'users_group';

            }

        });

    }

    // in this keybuffer we will gather current value of search !

    // since we need to get this just when someone does `@` then we do the

    // search

    ownerAC.dataSource.chunks = [];

    ownerAC.dataSource.mentionQuery = null;

    ownerAC.get_mention = function(msg, max_pos) {

    	var org = msg;

    	var re = new RegExp('(?:^@|\s@)([a-zA-Z0-9]{1}[a-zA-Z0-9\-\_\.]+)$')

    	var chunks  = [];

    	// cut first chunk until curret pos

		var to_max = msg.substr(0, max_pos);		

		var at_pos = Math.max(0,to_max.lastIndexOf('@')-1);

		var msg2 = to_max.substr(at_pos);

		chunks.push(org.substr(0,at_pos))// prefix chunk

		chunks.push(msg2)                // search chunk

		chunks.push(org.substr(max_pos)) // postfix chunk

		// clean up msg2 for filtering and regex match

		var msg2 = msg2.lstrip(' ').lstrip('\n');

		if(re.test(msg2)){

			var unam = re.exec(msg2)[1];

			return [unam, chunks];

		}

		return [null, null];