from sqlalchemy.orm import joinedload

from webob.exc import HTTPFound, HTTPBadRequest, HTTPForbidden, HTTPMethodNotAllowed

from kallithea import __platform__, is_windows, is_unix

from kallithea.config.routing import url

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

from kallithea.model.meta import Session

from kallithea.model.user import UserModel

from kallithea.model.db import User, Repository, Permission, \

    UserToPerm, UserGroupRepoToPerm, UserGroupToPerm, UserGroupMember, \

    RepoGroup, UserGroupRepoGroupToPerm, UserIpMap, UserGroupUserGroupToPerm, \

    UserGroup, UserApiKeys

from kallithea.lib.utils2 import safe_str, safe_unicode, aslist

from kallithea.lib.utils import get_repo_slug, get_repo_group_slug, \

    get_user_group_slug, conditional_cache

from kallithea.lib.caching_query import FromCache

log = logging.getLogger(__name__)

class PasswordGenerator(object):

    """

    This is a simple class for generating password from different sets of

    characters

    usage::

        passwd_gen = PasswordGenerator()

        #print 8-letter password containing only big and small letters

            of alphabet

        passwd_gen.gen_password(8, passwd_gen.ALPHABETS_BIG_SMALL)

    """

    ALPHABETS_NUM = r'''1234567890'''

    ALPHABETS_SMALL = r'''qwertyuiopasdfghjklzxcvbnm'''

    ALPHABETS_BIG = r'''QWERTYUIOPASDFGHJKLZXCVBNM'''

    ALPHABETS_SPECIAL = r'''`-=[]\;',./~!@#$%^&*()_+{}|:"<>?'''

    ALPHABETS_FULL = ALPHABETS_BIG + ALPHABETS_SMALL \

        + ALPHABETS_NUM + ALPHABETS_SPECIAL

    ALPHABETS_ALPHANUM = ALPHABETS_BIG + ALPHABETS_SMALL + ALPHABETS_NUM

    ALPHABETS_BIG_SMALL = ALPHABETS_BIG + ALPHABETS_SMALL

    ALPHABETS_ALPHANUM_BIG = ALPHABETS_BIG + ALPHABETS_NUM

    ALPHABETS_ALPHANUM_SMALL = ALPHABETS_SMALL + ALPHABETS_NUM

    def gen_password(self, length, alphabet=ALPHABETS_FULL):

        assert len(alphabet) <= 256, alphabet

        l = []

        while len(l) < length:

            i = ord(os.urandom(1))

            if i < len(alphabet):

                l.append(alphabet[i])

        return ''.join(l)

def get_crypt_password(password):

    """

    Cryptographic function used for password hashing based on pybcrypt

    or Python's own OpenSSL wrapper on windows

    :param password: password to hash

    """

    if is_windows:

        return hashlib.sha256(password).hexdigest()

    elif is_unix:

        import bcrypt

        return bcrypt.hashpw(safe_str(password), bcrypt.gensalt(10))

    else:

        raise Exception('Unknown or unsupported platform %s'

                        % __platform__)

def check_password(password, hashed):

    """

    Checks matching password with it's hashed value, runs different

    implementation based on platform it runs on

    :param password: password

    :param hashed: password in hashed form

    """

    if is_windows:

        return hashlib.sha256(password).hexdigest() == hashed

    elif is_unix:

        import bcrypt

        try:

            return bcrypt.checkpw(safe_str(password), safe_str(hashed))

        except ValueError as e:

            # bcrypt will throw ValueError 'Invalid hashed_password salt' on all password errors

            log.error('error from bcrypt checking password: %s', e)

            return False

    else:

        raise Exception('Unknown or unsupported platform %s'

                        % __platform__)

def _cached_perms_data(user_id, user_is_admin, user_inherit_default_permissions,

    RK = 'repositories'

    GK = 'repositories_groups'

    UK = 'user_groups'

    GLOBAL = 'global'

    PERM_WEIGHTS = Permission.PERM_WEIGHTS

    permissions = {RK: {}, GK: {}, UK: {}, GLOBAL: set()}

    def _choose_perm(new_perm, cur_perm):

        new_perm_val = PERM_WEIGHTS[new_perm]

        cur_perm_val = PERM_WEIGHTS[cur_perm]

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

    # fetch default permissions

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

    default_user = User.get_by_username('default', cache=True)

    default_user_id = default_user.user_id

    default_repo_perms = Permission.get_default_perms(default_user_id)

    default_repo_groups_perms = Permission.get_default_group_perms(default_user_id)

    default_user_group_perms = Permission.get_default_user_group_perms(default_user_id)

    if user_is_admin:

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

        # admin users have all rights;

        # based on default permissions, just set everything to admin

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

        permissions[GLOBAL].add('hg.admin')

        permissions[GLOBAL].add('hg.create.write_on_repogroup.true')

        # repositories

        for perm in default_repo_perms:

            r_k = perm.UserRepoToPerm.repository.repo_name

            p = 'repository.admin'

            permissions[RK][r_k] = p

        # repository groups

        for perm in default_repo_groups_perms:

            rg_k = perm.UserRepoGroupToPerm.group.group_name

            p = 'group.admin'

            permissions[GK][rg_k] = p

        # user groups

        for perm in default_user_group_perms:

            u_k = perm.UserUserGroupToPerm.user_group.users_group_name

            p = 'usergroup.admin'

            permissions[UK][u_k] = p

        return permissions

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

    # SET DEFAULTS GLOBAL, REPOS, REPOSITORY GROUPS

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

    # default global permissions taken from the default user

    default_global_perms = UserToPerm.query() \

        .filter(UserToPerm.user_id == default_user_id) \

        .options(joinedload(UserToPerm.permission))

    for perm in default_global_perms:

        permissions[GLOBAL].add(perm.permission.permission_name)

    # defaults for repositories, taken from default user

    for perm in default_repo_perms:

        r_k = perm.UserRepoToPerm.repository.repo_name

        if perm.Repository.private and not (perm.Repository.owner_id == user_id):

            # disable defaults for private repos,

            p = 'repository.none'

        elif perm.Repository.owner_id == user_id:

            # set admin if owner

            p = 'repository.admin'

        else:

            p = perm.Permission.permission_name

        permissions[RK][r_k] = p

    # defaults for repository groups taken from default user permission

    # on given group

    for perm in default_repo_groups_perms:

        rg_k = perm.UserRepoGroupToPerm.group.group_name

        p = perm.Permission.permission_name

        permissions[GK][rg_k] = p

    # defaults for user groups taken from default user permission

    # on given user group

    for perm in default_user_group_perms:

        u_k = perm.UserUserGroupToPerm.user_group.users_group_name

        p = perm.Permission.permission_name

        permissions[UK][u_k] = p

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

    # !! OVERRIDE GLOBALS !! with user permissions if any found

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

    # those can be configured from groups or users explicitly

    _configurable = set([

        'hg.fork.none', 'hg.fork.repository',

        'hg.create.none', 'hg.create.repository',

        'hg.usergroup.create.false', 'hg.usergroup.create.true'

    ])

    # USER GROUPS comes first

    # user group global permissions

    user_perms_from_users_groups = Session().query(UserGroupToPerm) \

        .options(joinedload(UserGroupToPerm.permission)) \

        .join((UserGroupMember, UserGroupToPerm.users_group_id ==

               UserGroupMember.users_group_id)) \

        .filter(UserGroupMember.user_id == user_id) \

        .join((UserGroup, UserGroupMember.users_group_id ==

               UserGroup.users_group_id)) \

        .filter(UserGroup.users_group_active == True) \

        .order_by(UserGroupToPerm.users_group_id) \

        .all()

    # need to group here by groups since user can be in more than

    # one group

    _grouped = [[x, list(y)] for x, y in

                itertools.groupby(user_perms_from_users_groups,

                                  lambda x:x.users_group)]

    for gr, perms in _grouped:

        # since user can be in multiple groups iterate over them and

        # select the lowest permissions first (more explicit)

        # TODO: do this^^

        if not gr.inherit_default_permissions:

            # NEED TO IGNORE all configurable permissions and

            # replace them with explicitly set

            permissions[GLOBAL] = permissions[GLOBAL] \

                                            .difference(_configurable)

        for perm in perms:

            permissions[GLOBAL].add(perm.permission.permission_name)

    # user specific global permissions

    user_perms = Session().query(UserToPerm) \

            .options(joinedload(UserToPerm.permission)) \

            .filter(UserToPerm.user_id == user_id).all()

    if not user_inherit_default_permissions:

        # NEED TO IGNORE all configurable permissions and

        # replace them with explicitly set

        permissions[GLOBAL] = permissions[GLOBAL] \

                                        .difference(_configurable)

        for perm in user_perms:

            permissions[GLOBAL].add(perm.permission.permission_name)

    ## END GLOBAL PERMISSIONS

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

    # !! PERMISSIONS FOR REPOSITORIES !!

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

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

    # check if user is part of user groups for this repository and

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

    # user group for repositories permissions

    user_repo_perms_from_users_groups = \

     Session().query(UserGroupRepoToPerm, Permission, Repository,) \

        .join((Repository, UserGroupRepoToPerm.repository_id ==

               Repository.repo_id)) \

        .join((Permission, UserGroupRepoToPerm.permission_id ==

               Permission.permission_id)) \

        .join((UserGroup, UserGroupRepoToPerm.users_group_id ==

               UserGroup.users_group_id)) \

        .filter(UserGroup.users_group_active == True) \

        .join((UserGroupMember, UserGroupRepoToPerm.users_group_id ==

               UserGroupMember.users_group_id)) \

        .filter(UserGroupMember.user_id == user_id) \

        .all()

    multiple_counter = collections.defaultdict(int)

    for perm in user_repo_perms_from_users_groups:

        r_k = perm.UserGroupRepoToPerm.repository.repo_name

        multiple_counter[r_k] += 1

        p = perm.Permission.permission_name

        cur_perm = permissions[RK][r_k]

        if perm.Repository.owner_id == user_id:

            # set admin if owner

            p = 'repository.admin'

        else:

            if multiple_counter[r_k] > 1:

                p = _choose_perm(p, cur_perm)

        permissions[RK][r_k] = p

    # user explicit permissions for repositories, overrides any specified

    # by the group permission

    user_repo_perms = Permission.get_default_perms(user_id)

    for perm in user_repo_perms:

        r_k = perm.UserRepoToPerm.repository.repo_name

        cur_perm = permissions[RK][r_k]

        # set admin if owner

        if perm.Repository.owner_id == user_id:

            p = 'repository.admin'

        else:

            p = perm.Permission.permission_name

            if not explicit:

                p = _choose_perm(p, cur_perm)

        permissions[RK][r_k] = p

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

    # !! PERMISSIONS FOR REPOSITORY GROUPS !!

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

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

    # check if user is part of user groups for this repository groups and

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

    # user group for repo groups permissions

    user_repo_group_perms_from_users_groups = \

     Session().query(UserGroupRepoGroupToPerm, Permission, RepoGroup) \

     .join((RepoGroup, UserGroupRepoGroupToPerm.group_id == RepoGroup.group_id)) \

     .join((Permission, UserGroupRepoGroupToPerm.permission_id

            == Permission.permission_id)) \

     .join((UserGroup, UserGroupRepoGroupToPerm.users_group_id ==

            UserGroup.users_group_id)) \

     .filter(UserGroup.users_group_active == True) \

     .join((UserGroupMember, UserGroupRepoGroupToPerm.users_group_id

            == UserGroupMember.users_group_id)) \

     .filter(UserGroupMember.user_id == user_id) \

     .all()

    multiple_counter = collections.defaultdict(int)

    for perm in user_repo_group_perms_from_users_groups:

        g_k = perm.UserGroupRepoGroupToPerm.group.group_name

        multiple_counter[g_k] += 1

        p = perm.Permission.permission_name

        cur_perm = permissions[GK][g_k]

        if multiple_counter[g_k] > 1:

            p = _choose_perm(p, cur_perm)

        permissions[GK][g_k] = p

    # user explicit permissions for repository groups

    user_repo_groups_perms = Permission.get_default_group_perms(user_id)

    for perm in user_repo_groups_perms:

        rg_k = perm.UserRepoGroupToPerm.group.group_name

        p = perm.Permission.permission_name

        cur_perm = permissions[GK][rg_k]

        if not explicit:

            p = _choose_perm(p, cur_perm)

        permissions[GK][rg_k] = p

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

    # !! PERMISSIONS FOR USER GROUPS !!

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

    # user group for user group permissions

    user_group_user_groups_perms = \

     Session().query(UserGroupUserGroupToPerm, Permission, UserGroup) \

     .join((UserGroup, UserGroupUserGroupToPerm.target_user_group_id

            == UserGroup.users_group_id)) \

     .join((Permission, UserGroupUserGroupToPerm.permission_id

            == Permission.permission_id)) \

     .join((UserGroupMember, UserGroupUserGroupToPerm.user_group_id

            == UserGroupMember.users_group_id)) \

     .filter(UserGroupMember.user_id == user_id) \

     .join((UserGroup, UserGroupMember.users_group_id ==

            UserGroup.users_group_id), aliased=True, from_joinpoint=True) \

     .filter(UserGroup.users_group_active == True) \

     .all()

    multiple_counter = collections.defaultdict(int)

    for perm in user_group_user_groups_perms:

        g_k = perm.UserGroupUserGroupToPerm.target_user_group.users_group_name

        multiple_counter[g_k] += 1

        p = perm.Permission.permission_name

        cur_perm = permissions[UK][g_k]

        if multiple_counter[g_k] > 1:

            p = _choose_perm(p, cur_perm)

        permissions[UK][g_k] = p

    # user explicit permission for user groups

    user_user_groups_perms = Permission.get_default_user_group_perms(user_id)

    for perm in user_user_groups_perms:

        u_k = perm.UserUserGroupToPerm.user_group.users_group_name

        p = perm.Permission.permission_name

        cur_perm = permissions[UK][u_k]

        if not explicit:

            p = _choose_perm(p, cur_perm)

        permissions[UK][u_k] = p

    return permissions

def allowed_api_access(controller_name, whitelist=None, api_key=None):

    """

    Check if given controller_name is in whitelist API access

    """

    if not whitelist:

        from kallithea import CONFIG

        whitelist = aslist(CONFIG.get('api_access_controllers_whitelist'),

                           sep=',')

        log.debug('whitelist of API access is: %s', whitelist)

    api_access_valid = controller_name in whitelist

    if api_access_valid:

        log.debug('controller:%s is in API whitelist', controller_name)

    else:

        msg = 'controller: %s is *NOT* in API whitelist' % (controller_name)

        if api_key:

            # if we use API key and don't have access it's a warning

            log.warning(msg)

        else:

            log.debug(msg)

    return api_access_valid

        # not enabled.

        self.user_id = None

        self.username = None

        self.api_key = None

        self.name = ''

        self.lastname = ''

        self.email = ''

        self.admin = False

        self.inherit_default_permissions = False

        # Look up database user, if necessary.

        if user_id is not None:

            log.debug('Auth User lookup by USER ID %s', user_id)

            dbuser = UserModel().get(user_id)

        else:

            # Note: dbuser is allowed to be None.

            log.debug('Auth User lookup by database user %s', dbuser)

        is_user_loaded = self._fill_data(dbuser)

        # If user cannot be found, try falling back to anonymous.

        if is_user_loaded:

            assert dbuser is not None

            self.is_default_user = dbuser.is_default_user

        else:

            default_user = User.get_default_user(cache=True)

            is_user_loaded = self._fill_data(default_user)

            self.is_default_user = is_user_loaded

        self.is_anonymous = not is_user_loaded or self.is_default_user

        if not self.username:

            self.username = 'None'

        log.debug('Auth User is now %s', self)

    def _fill_data(self, dbuser):

        """

        Copies database fields from a `db.User` to this `AuthUser`. Does

        not copy `api_keys` and `permissions` attributes.

        Checks that `dbuser` is `active` (and not None) before copying;

        returns True on success.

        """

        if dbuser is not None and dbuser.active:

            log.debug('filling %s data', dbuser)

            for k, v in dbuser.get_dict().iteritems():

                assert k not in ['api_keys', 'permissions']

                setattr(self, k, v)

            return True

        return False

    @LazyProperty

    def permissions(self):

        return self.__get_perms(user=self, cache=False)

    def has_repository_permission_level(self, repo_name, level, purpose=None):

        required_perms = {

            'read': ['repository.read', 'repository.write', 'repository.admin'],

            'write': ['repository.write', 'repository.admin'],

            'admin': ['repository.admin'],

        }[level]

        actual_perm = self.permissions['repositories'].get(repo_name)

        ok = actual_perm in required_perms

        log.debug('Checking if user %r can %r repo %r (%s): %s (has %r)',

            self.username, level, repo_name, purpose, ok, actual_perm)

        return ok

    def has_repository_group_permission_level(self, repo_group_name, level, purpose=None):

        required_perms = {

            'read': ['group.read', 'group.write', 'group.admin'],

            'write': ['group.write', 'group.admin'],

            'admin': ['group.admin'],

        }[level]

        actual_perm = self.permissions['repositories_groups'].get(repo_group_name)

        ok = actual_perm in required_perms

        log.debug('Checking if user %r can %r repo group %r (%s): %s (has %r)',

            self.username, level, repo_group_name, purpose, ok, actual_perm)

        return ok

    def has_user_group_permission_level(self, user_group_name, level, purpose=None):

        required_perms = {

            'read': ['usergroup.read', 'usergroup.write', 'usergroup.admin'],

            'write': ['usergroup.write', 'usergroup.admin'],

            'admin': ['usergroup.admin'],

        }[level]

        actual_perm = self.permissions['user_groups'].get(user_group_name)

        ok = actual_perm in required_perms

        log.debug('Checking if user %r can %r user group %r (%s): %s (has %r)',

            self.username, level, user_group_name, purpose, ok, actual_perm)

        return ok

    @property

    def api_keys(self):

        return self._get_api_keys()

        """

        Fills user permission attribute with permissions taken from database

        works for permissions given for repositories, and for permissions that

        are granted to groups

        :param user: `AuthUser` instance

        :param explicit: In case there are permissions both for user and a group

            that user is part of, explicit flag will define if user will

            explicitly override permissions from group, if it's False it will

        """

        user_id = user.user_id

        user_is_admin = user.is_admin

        user_inherit_default_permissions = user.inherit_default_permissions

        log.debug('Getting PERMISSION tree')

        compute = conditional_cache('short_term', 'cache_desc',

                                    condition=cache, func=_cached_perms_data)

        return compute(user_id, user_is_admin,

    def _get_api_keys(self):

        api_keys = [self.api_key]

        for api_key in UserApiKeys.query() \

                .filter_by(user_id=self.user_id, is_expired=False):

            api_keys.append(api_key.api_key)

        return api_keys

    @property

    def is_admin(self):

        return self.admin

    @property

    def repositories_admin(self):

        """

        Returns list of repositories you're an admin of

        """

        return [x[0] for x in self.permissions['repositories'].iteritems()

                if x[1] == 'repository.admin']

    @property

    def repository_groups_admin(self):

        """

        Returns list of repository groups you're an admin of

        """

        return [x[0] for x in self.permissions['repositories_groups'].iteritems()

                if x[1] == 'group.admin']

    @property

    def user_groups_admin(self):

        """

        Returns list of user groups you're an admin of

        """

        return [x[0] for x in self.permissions['user_groups'].iteritems()

                if x[1] == 'usergroup.admin']

    @staticmethod

    def check_ip_allowed(user, ip_addr):

        """

        Check if the given IP address (a `str`) is allowed for the given

        user (an `AuthUser` or `db.User`).

        """

        allowed_ips = AuthUser.get_allowed_ips(user.user_id, cache=True,

            inherit_from_default=user.inherit_default_permissions)

        if check_ip_access(source_ip=ip_addr, allowed_ips=allowed_ips):

            log.debug('IP:%s is in range of %s', ip_addr, allowed_ips)

            return True

        else:

            log.info('Access for IP:%s forbidden, '

                     'not in %s' % (ip_addr, allowed_ips))

            return False

    def __repr__(self):

        return "<AuthUser('id:%s[%s] auth:%s')>" \

            % (self.user_id, self.username, (self.is_authenticated or self.is_default_user))

    def to_cookie(self):

        """ Serializes this login session to a cookie `dict`. """

        return {

            'user_id': self.user_id,

            'is_external_auth': self.is_external_auth,

        }

    @staticmethod

    def from_cookie(cookie):

        """

        Deserializes an `AuthUser` from a cookie `dict`.

        """

        au = AuthUser(

            user_id=cookie.get('user_id'),

            is_external_auth=cookie.get('is_external_auth', False),

        )

        au.is_authenticated = True

        return au

    @classmethod

    def get_allowed_ips(cls, user_id, cache=False, inherit_from_default=False):

        _set = set()

        if inherit_from_default:

            default_ips = UserIpMap.query().filter(UserIpMap.user_id ==

                                            User.get_default_user(cache=True).user_id)

            if cache:

                default_ips = default_ips.options(FromCache("sql_cache_short",

                                                  "get_user_ips_default"))

            # populate from default user

            for ip in default_ips:

                try:

                    _set.add(ip.ip_addr)

                except ObjectDeletedError:

                    # since we use heavy caching sometimes it happens that we get

                    # deleted objects here, we just skip them

                    pass