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

# 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/>.

"""

kallithea.controllers.admin.repo_groups

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

Repository groups controller for Kallithea

This file was forked by the Kallithea project in July 2014.

Original author and date, and relevant copyright and licensing information is below:

:created_on: Mar 23, 2010

:author: marcink

:copyright: (c) 2013 RhodeCode GmbH, and others.

:license: GPLv3, see LICENSE.md for more details.

"""

import logging

import traceback

import formencode

import itertools

from formencode import htmlfill

from pylons import request, tmpl_context as c, url

from pylons.controllers.util import abort, redirect

from pylons.i18n.translation import _, ungettext

import kallithea

from kallithea.lib import helpers as h

from kallithea.lib.compat import json

from kallithea.lib.auth import LoginRequired, HasPermissionAnyDecorator,\

    HasRepoGroupPermissionAnyDecorator, HasRepoGroupPermissionAll,\

    HasPermissionAll

from kallithea.lib.base import BaseController, render

from kallithea.model.db import RepoGroup, Repository

from kallithea.model.scm import RepoGroupList

from kallithea.model.repo_group import RepoGroupModel

from kallithea.model.forms import RepoGroupForm, RepoGroupPermsForm

from kallithea.model.meta import Session

from kallithea.model.repo import RepoModel

from webob.exc import HTTPInternalServerError, HTTPNotFound

from kallithea.lib.utils2 import safe_int

from sqlalchemy.sql.expression import func

log = logging.getLogger(__name__)

class RepoGroupsController(BaseController):

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

    @LoginRequired()

    def __before__(self):

        super(RepoGroupsController, self).__before__()

    def __load_defaults(self, allow_empty_group=False, exclude_group_ids=[]):

        if HasPermissionAll('hg.admin')('group edit'):

            #we're global admin, we're ok and we can create TOP level groups

            allow_empty_group = True

        #override the choices for this form, we need to filter choices

        #and display only those we have ADMIN right

        groups_with_admin_rights = RepoGroupList(RepoGroup.query().all(),

                                                 perm_set=['group.admin'])

        c.repo_groups = RepoGroup.groups_choices(groups=groups_with_admin_rights,

                                                 show_empty_group=allow_empty_group)

        # exclude filtered ids

        c.repo_groups = filter(lambda x: x[0] not in exclude_group_ids,

                               c.repo_groups)

        c.repo_groups_choices = map(lambda k: unicode(k[0]), c.repo_groups)

        repo_model = RepoModel()

        c.users_array = repo_model.get_users_js()

        c.user_groups_array = repo_model.get_user_groups_js()

    def __load_data(self, group_id):

        """

        Load defaults settings for edit, and update

        :param group_id:

        """

        repo_group = RepoGroup.get_or_404(group_id)

        data = repo_group.get_dict()

        data['group_name'] = repo_group.name

        # fill repository group users

        for p in repo_group.repo_group_to_perm:

            data.update({'u_perm_%s' % p.user.username:

                             p.permission.permission_name})

        # fill repository group groups

        for p in repo_group.users_group_to_perm:

            data.update({'g_perm_%s' % p.users_group.users_group_name:

                             p.permission.permission_name})

        return data

    def _revoke_perms_on_yourself(self, form_result):

        _up = filter(lambda u: c.authuser.username == u[0],

                     form_result['perms_updates'])

        _new = filter(lambda u: c.authuser.username == u[0],

                      form_result['perms_new'])

        if _new and _new[0][1] != 'group.admin' or _up and _up[0][1] != 'group.admin':

            return True

        return False

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

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

        # url('repos_groups')

        _list = RepoGroup.query()\

                    .order_by(func.lower(RepoGroup.group_name))\

                    .all()

        group_iter = RepoGroupList(_list, perm_set=['group.admin'])

        repo_groups_data = []

        total_records = len(group_iter)

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

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

        repo_group_name = lambda repo_group_name, children_groups: (

            template.get_def("repo_group_name")

            .render(repo_group_name, children_groups, _=_, h=h, c=c)

        )

        repo_group_actions = lambda repo_group_id, repo_group_name, gr_count: (

            template.get_def("repo_group_actions")

            .render(repo_group_id, repo_group_name, gr_count, _=_, h=h, c=c,

                    ungettext=ungettext)

        )

        for repo_gr in group_iter:

            children_groups = map(h.safe_unicode,

                itertools.chain((g.name for g in repo_gr.parents),

                                (x.name for x in [repo_gr])))

            repo_count = repo_gr.repositories.count()

            repo_groups_data.append({

                "raw_name": repo_gr.group_name,

                "group_name": repo_group_name(repo_gr.group_name, children_groups),

                "desc": repo_gr.group_description,

                "repos": repo_count,

                "action": repo_group_actions(repo_gr.group_id, repo_gr.group_name,

                                             repo_count)

            })

        c.data = json.dumps({

            "totalRecords": total_records,

            "startIndex": 0,

            "sort": None,

            "dir": "asc",

            "records": repo_groups_data

        })

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

    def create(self):

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

        # url('repos_groups')

        self.__load_defaults()

        # permissions for can create group based on parent_id are checked

        # here in the Form

        repo_group_form = RepoGroupForm(available_groups=

                                map(lambda k: unicode(k[0]), c.repo_groups))()

        try:

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

            RepoGroupModel().create(

                group_name=form_result['group_name'],

                group_description=form_result['group_description'],

                parent=form_result['group_parent_id'],

                owner=self.authuser.user_id,

                copy_permissions=form_result['group_copy_permissions']

            )

            Session().commit()

            h.flash(_('Created repository group %s') \

                    % form_result['group_name'], category='success')

            #TODO: in futureaction_logger(, '', '', '', self.sa)

        except formencode.Invalid, errors:

            return htmlfill.render(

                render('admin/repo_groups/repo_group_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 repository group %s') \

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

        parent_group_id = form_result['group_parent_id']

        #TODO: maybe we should get back to the main view, not the admin one

        return redirect(url('repos_groups', parent_group=parent_group_id))

    def new(self):

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

        # url('new_repos_group')

        if HasPermissionAll('hg.admin')('group create'):

            #we're global admin, we're ok and we can create TOP level groups

            pass

        else:

            # we pass in parent group into creation form, thus we know

            # what would be the group, we can check perms here !

            group_id = safe_int(request.GET.get('parent_group'))

            group = RepoGroup.get(group_id) if group_id else None

            group_name = group.group_name if group else None

            if HasRepoGroupPermissionAll('group.admin')(group_name, 'group create'):

                pass

            else:

                return abort(403)

        self.__load_defaults()

        return render('admin/repo_groups/repo_group_add.html')

    @HasRepoGroupPermissionAnyDecorator('group.admin')

    def update(self, group_name):

        """PUT /repo_groups/group_name: 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('repos_group', group_name=GROUP_NAME),

        #           method='put')

        # url('repos_group', group_name=GROUP_NAME)

        c.repo_group = RepoGroupModel()._get_repo_group(group_name)

        if HasPermissionAll('hg.admin')('group edit'):

            #we're global admin, we're ok and we can create TOP level groups

            allow_empty_group = True

        elif not c.repo_group.parent_group:

            allow_empty_group = True

        else:

            allow_empty_group = False

        self.__load_defaults(allow_empty_group=allow_empty_group,

                             exclude_group_ids=[c.repo_group.group_id])

        repo_group_form = RepoGroupForm(

            edit=True,

            old_data=c.repo_group.get_dict(),

            available_groups=c.repo_groups_choices,

            can_create_in_root=allow_empty_group,

        )()

        try:

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

            new_gr = RepoGroupModel().update(group_name, form_result)

            Session().commit()

            h.flash(_('Updated repository group %s') \

                    % form_result['group_name'], category='success')

            # we now have new name !

            group_name = new_gr.group_name

            #TODO: in future action_logger(, '', '', '', self.sa)

        except formencode.Invalid, errors:

            return htmlfill.render(

                render('admin/repo_groups/repo_group_edit.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 update of repository group %s') \

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

        return redirect(url('edit_repo_group', group_name=group_name))

    @HasRepoGroupPermissionAnyDecorator('group.admin')

    def delete(self, group_name):

        """DELETE /repo_groups/group_name: 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('repos_group', group_name=GROUP_NAME),

        #           method='delete')

        # url('repos_group', group_name=GROUP_NAME)

        gr = c.repo_group = RepoGroupModel()._get_repo_group(group_name)

        repos = gr.repositories.all()

        if repos:

            h.flash(_('This group contains %s repositores and cannot be '

                      'deleted') % len(repos), category='warning')

            return redirect(url('repos_groups'))

        children = gr.children.all()

        if children:

            h.flash(_('This group contains %s subgroups and cannot be deleted'

                      % (len(children))), category='warning')

            return redirect(url('repos_groups'))

        try:

            RepoGroupModel().delete(group_name)

            Session().commit()

            h.flash(_('Removed repository group %s') % group_name,

                    category='success')

            #TODO: in future action_logger(, '', '', '', self.sa)

        except Exception:

            log.error(traceback.format_exc())

            h.flash(_('Error occurred during deletion of repository group %s')

                    % group_name, category='error')

        if gr.parent_group:

            return redirect(url('repos_group_home', group_name=gr.parent_group.group_name))

        return redirect(url('repos_groups'))

    def show_by_name(self, group_name):

        """

        This is a proxy that does a lookup group_name -> id, and shows

        the group by id view instead

        """

        group_name = group_name.rstrip('/')

        id_ = RepoGroup.get_by_group_name(group_name)

        if id_:

            return self.show(group_name)

        raise HTTPNotFound

    @HasRepoGroupPermissionAnyDecorator('group.read', 'group.write',

                                         'group.admin')

    def show(self, group_name):

        """GET /repo_groups/group_name: Show a specific item"""

        # url('repos_group', group_name=GROUP_NAME)

        c.active = 'settings'

        c.group = c.repo_group = RepoGroupModel()._get_repo_group(group_name)

        c.group_repos = c.group.repositories.all()

        #overwrite our cached list with current filter

        c.repo_cnt = 0

        groups = RepoGroup.query().order_by(RepoGroup.group_name)\

            .filter(RepoGroup.group_parent_id == c.group.group_id).all()

        c.groups = self.scm_model.get_repo_groups(groups)

        c.repos_list = Repository.query()\

                        .filter(Repository.group_id == c.group.group_id)\

                return v, v, v

            i = int(h * 6.0)  # XXX assume int() truncates!

            f = (h * 6.0) - i

            p = v * (1.0 - s)

            q = v * (1.0 - s * f)

            t = v * (1.0 - s * (1.0 - f))

            i = i % 6

            if i == 0:

                return v, t, p

            if i == 1:

                return q, v, p

            if i == 2:

                return p, v, t

            if i == 3:

                return p, q, v

            if i == 4:

                return t, p, v

            if i == 5:

                return v, p, q

        golden_ratio = 0.618033988749895

        h = 0.22717784590367374

        for _unused in xrange(n):

            h += golden_ratio

            h %= 1

            HSV_tuple = [h, 0.95, 0.95]

            RGB_tuple = hsv_to_rgb(*HSV_tuple)

            yield map(lambda x: str(int(x * 256)), RGB_tuple)

    cgenerator = gen_color()

    def get_color_string(cs):

        if cs in color_dict:

            col = color_dict[cs]

        else:

            col = color_dict[cs] = cgenerator.next()

        return "color: rgb(%s)! important;" % (', '.join(col))

    def url_func(repo_name):

        def _url_func(changeset):

            author = changeset.author

            date = changeset.date

            message = tooltip(changeset.message)

            tooltip_html = ("<div style='font-size:0.8em'><b>Author:</b>"

                            " %s<br/><b>Date:</b> %s</b><br/><b>Message:"

                            "</b> %s<br/></div>")

            tooltip_html = tooltip_html % (author, date, message)

            lnk_format = show_id(changeset)

            uri = link_to(

                    lnk_format,

                    url('changeset_home', repo_name=repo_name,

                        revision=changeset.raw_id),

                    style=get_color_string(changeset.raw_id),

                    class_='tooltip',

                    title=tooltip_html

                  )

            uri += '\n'

            return uri

        return _url_func

    return literal(markup_whitespace(annotate_highlight(filenode, url_func(repo_name), **kwargs)))

def is_following_repo(repo_name, user_id):

    from kallithea.model.scm import ScmModel

    return ScmModel().is_following_repo(repo_name, user_id)

class _Message(object):

    """A message returned by ``Flash.pop_messages()``.

    Converting the message to a string returns the message text. Instances

    also have the following attributes:

    * ``message``: the message text.

    * ``category``: the category specified when the message was created.

    """

    def __init__(self, category, message):

        self.category = category

        self.message = message

    def __str__(self):

        return self.message

    __unicode__ = __str__

    def __html__(self):

        return escape(safe_unicode(self.message))

class Flash(_Flash):

    def pop_messages(self):

        """Return all accumulated messages and delete them from the session.

        The return value is a list of ``Message`` objects.

        """

        from pylons import session

        messages = session.pop(self.session_key, [])

        session.save()

        return [_Message(*m) for m in messages]

flash = Flash()

#==============================================================================

# SCM FILTERS available via h.

#==============================================================================

from kallithea.lib.vcs.utils import author_name, author_email

from kallithea.lib.utils2 import credentials_filter, age as _age

from kallithea.model.db import User, ChangesetStatus

age = lambda  x, y=False: _age(x, y)

capitalize = lambda x: x.capitalize()

email = author_email

short_id = lambda x: x[:12]

hide_credentials = lambda x: ''.join(credentials_filter(x))

def show_id(cs):

    """

    Configurable function that shows ID

    by default it's r123:fffeeefffeee

    :param cs: changeset instance

    """

    from kallithea import CONFIG

    def_len = safe_int(CONFIG.get('show_sha_length', 12))

    show_rev = str2bool(CONFIG.get('show_revision_number', False))

    raw_id = cs.raw_id[:def_len]

    if show_rev:

        return 'r%s:%s' % (cs.revision, raw_id)

    else:

        return '%s' % (raw_id)

def fmt_date(date):

    if date:

        _fmt = u"%a, %d %b %Y %H:%M:%S".encode('utf8')

        return date.strftime(_fmt).decode('utf8')

    return ""

def is_git(repository):

    if hasattr(repository, 'alias'):

        _type = repository.alias

    elif hasattr(repository, 'repo_type'):

        _type = repository.repo_type

    else:

        _type = repository

    return _type == 'git'

def is_hg(repository):

    if hasattr(repository, 'alias'):

        _type = repository.alias

    elif hasattr(repository, 'repo_type'):

        _type = repository.repo_type

    else:

        _type = repository

    return _type == 'hg'

def email_or_none(author):

    if not author:

        return None

    # extract email from the commit string

    _email = email(author)

    if _email:

        # check it against Kallithea database, and use the MAIN email for this

        # user

        user = User.get_by_email(_email, case_insensitive=True, cache=True)

        if user is not None:

            return user.email

        return _email

    # See if it contains a username we can get an email from

    user = User.get_by_username(author_name(author), case_insensitive=True,

                                cache=True)

    if user is not None:

        return user.email

    # No valid email, not a valid user in the system, none!

    return None

def person(author, show_attr="username"):

    # attr to return from fetched user

    person_getter = lambda usr: getattr(usr, show_attr)

    # if author is already an instance use it for extraction

    if isinstance(author, User):

        return person_getter(author)

    # Valid email in the attribute passed, see if they're in the system

    _email = email(author)

    if _email:

        user = User.get_by_email(_email, case_insensitive=True, cache=True)

        if user is not None:

            return person_getter(user)

    # Maybe it's a username?

    _author = author_name(author)

    user = User.get_by_username(_author, case_insensitive=True,

                                cache=True)

    if user is not None:

        return person_getter(user)

    # Still nothing?  Just pass back the author name if any, else the email

    return _author or _email

def person_by_id(id_, show_attr="username"):

    # attr to return from fetched user

    person_getter = lambda usr: getattr(usr, show_attr)

    #maybe it's an ID ?

    if str(id_).isdigit() or isinstance(id_, int):

        id_ = int(id_)

        user = User.get(id_)

        if user is not None:

            return person_getter(user)

    return id_

def desc_stylize(value):

    """

    converts tags from value into html equivalent

    :param value:

    """

    if not value:

        return ''

    value = re.sub(r'\[see\ \=\>\ *([a-zA-Z0-9\/\=\?\&\ \:\/\.\-]*)\]',

                   '<div class="metatag" tag="see">see =&gt; \\1 </div>', value)

    value = re.sub(r'\[license\ \=\>\ *([a-zA-Z0-9\/\=\?\&\ \:\/\.\-]*)\]',

                   '<div class="metatag" tag="license"><a href="http:\/\/www.opensource.org/licenses/\\1">\\1</a></div>', value)

    value = re.sub(r'\[(requires|recommends|conflicts|base)\ \=\>\ *([a-zA-Z0-9\-\/]*)\]',

                   '<div class="metatag" tag="\\1">\\1 =&gt; <a href="/\\2">\\2</a></div>', value)

    value = re.sub(r'\[(lang|language)\ \=\>\ *([a-zA-Z\-\/\#\+]*)\]',

                   '<div class="metatag" tag="lang">\\2</div>', value)

    value = re.sub(r'\[([a-z]+)\]',

                  '<div class="metatag" tag="\\1">\\1</div>', value)

    return value

def boolicon(value):

    """Returns boolean value of a value, represented as small html image of true/false

    icons

    :param value: value

    """

    if value:

        return HTML.tag('i', class_="icon-ok")

    else:

        return HTML.tag('i', class_="icon-minus-circled")

def action_parser(user_log, feed=False, parse_cs=False):

    """

    This helper will action_map the specified string action into translated

    fancy names with icons and links

    :param user_log: user log instance

    :param feed: use output for feeds (no html and fancy icons)

    :param parse_cs: parse Changesets into VCS instances

    """

    action = user_log.action

    action_params = ' '

    x = action.split(':')

    if len(x) > 1:

        action, action_params = x

    def get_cs_links():

        revs_limit = 3  # display this amount always

        revs_top_limit = 50  # show upto this amount of changesets hidden

        revs_ids = action_params.split(',')

        deleted = user_log.repository is None

        if deleted:

            return ','.join(revs_ids)

        repo_name = user_log.repository.repo_name

        def lnk(rev, repo_name):

            if isinstance(rev, BaseChangeset) or isinstance(rev, AttributeDict):

                lazy_cs = True

                if getattr(rev, 'op', None) and getattr(rev, 'ref_name', None):

                    lazy_cs = False

                    lbl = '?'

                    if rev.op == 'delete_branch':

                        lbl = '%s' % _('Deleted branch: %s') % rev.ref_name

                        title = ''

                    elif rev.op == 'tag':

                        lbl = '%s' % _('Created tag: %s') % rev.ref_name

                        title = ''

                    _url = '#'

                else:

                    lbl = '%s' % (rev.short_id[:8])

                    _url = url('changeset_home', repo_name=repo_name,

                               revision=rev.raw_id)

                    title = tooltip(rev.message)

            else:

                ## changeset cannot be found/striped/removed etc.

                lbl = ('%s' % rev)[:12]

                _url = '#'

                title = _('Changeset not found')

            if parse_cs:

                return link_to(lbl, _url, title=title, class_='tooltip')

            return link_to(lbl, _url, raw_id=rev.raw_id, repo_name=repo_name,

                           class_='lazy-cs' if lazy_cs else '')

        def _get_op(rev_txt):

            _op = None

            _name = rev_txt

            if len(rev_txt.split('=>')) == 2:

                _op, _name = rev_txt.split('=>')

            return _op, _name

        revs = []

        if len(filter(lambda v: v != '', revs_ids)) > 0:

            repo = None

            for rev in revs_ids[:revs_top_limit]:

                _op, _name = _get_op(rev)

                # we want parsed changesets, or new log store format is bad

                if parse_cs:

                    try:

                        if repo is None:

                            repo = user_log.repository.scm_instance

                        _rev = repo.get_changeset(rev)

                        revs.append(_rev)

                    except ChangesetDoesNotExistError:

                        log.error('cannot find revision %s in this repo' % rev)

                        revs.append(rev)

                        continue

                else:

                    _rev = AttributeDict({

                        'short_id': rev[:12],

                        'raw_id': rev,

                        'message': '',

                        'op': _op,

                        'ref_name': _name

                    })

                    revs.append(_rev)

        cs_links = [" " + ', '.join(

            [lnk(rev, repo_name) for rev in revs[:revs_limit]]

        )]

        _op1, _name1 = _get_op(revs_ids[0])

        _op2, _name2 = _get_op(revs_ids[-1])

        _rev = '%s...%s' % (_name1, _name2)

        compare_view = (

            ' <div class="compare_view tooltip" title="%s">'

            '<a href="%s">%s</a> </div>' % (

                _('Show all combined changesets %s->%s') % (

                    revs_ids[0][:12], revs_ids[-1][:12]

                ),

                url('changeset_home', repo_name=repo_name,

                    revision=_rev

                ),

                _('compare view')

            )

        )

        # if we have exactly one more than normally displayed

        # just display it, takes less space than displaying

        # "and 1 more revisions"

        if len(revs_ids) == revs_limit + 1:

            cs_links.append(", " + lnk(revs[revs_limit], repo_name))

        # hidden-by-default ones

"""

This module provides some useful tools for ``vcs`` like annotate/diff html

output. It also includes some internal helpers.

"""

import time

import datetime

def makedate():

    lt = time.localtime()

    if lt[8] == 1 and time.daylight:

        tz = time.altzone

    else:

        tz = time.timezone

    return time.mktime(lt), tz

def aslist(obj, sep=None, strip=True):

    """

    Returns given string separated by sep as list

    :param obj:

    :param sep:

    :param strip:

    """

    if isinstance(obj, (basestring)):

        lst = obj.split(sep)

        if strip:

            lst = [v.strip() for v in lst]

        return lst

    elif isinstance(obj, (list, tuple)):

        return obj

    elif obj is None:

        return []

    else:

        return [obj]

def date_fromtimestamp(unixts, tzoffset=0):

    """

    Makes a local datetime object out of unix timestamp

    :param unixts:

    :param tzoffset:

    """

    return datetime.datetime.fromtimestamp(float(unixts))

def safe_int(val, default=None):

    """

    Returns int() of val if val is not convertable to int use default

    instead

    :param val:

    :param default:

    """

    try:

        val = int(val)

    except (ValueError, TypeError):

        val = default

    return val

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:

        from kallithea.lib.vcs.conf import settings

        from_encoding = settings.DEFAULT_ENCODINGS

    if not isinstance(from_encoding, (list, tuple)):

        from_encoding = [from_encoding]

    try:

        return unicode(str_)

    except UnicodeDecodeError:

        pass

    for enc in from_encoding:

        try:

            return unicode(str_, enc)

        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[0], '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:

        from kallithea.lib.vcs.conf import settings

        to_encoding = settings.DEFAULT_ENCODINGS

    if not isinstance(to_encoding, (list, tuple)):

        to_encoding = [to_encoding]

    for enc in to_encoding:

        try:

            return unicode_.encode(enc)