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

"""

    vcs.backends.base

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

    Base for all available scm backends

    :created_on: Apr 8, 2010

    :copyright: (c) 2010-2011 by Marcin Kuzminski, Lukasz Balcerzak.

"""

import datetime

from itertools import chain

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

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

from rhodecode.lib.vcs.utils.helpers import get_dict_for_attrs

from rhodecode.lib.vcs.conf import settings

from rhodecode.lib.vcs.exceptions import ChangesetError, EmptyRepositoryError, \

    NodeAlreadyAddedError, NodeAlreadyChangedError, NodeAlreadyExistsError, \

    NodeAlreadyRemovedError, NodeDoesNotExistError, NodeNotChangedError, \

    RepositoryError

class BaseRepository(object):

    """

    Base Repository for final backends

    **Attributes**

        ``DEFAULT_BRANCH_NAME``

            name of default branch (i.e. "trunk" for svn, "master" for git etc.

        ``scm``

            alias of scm, i.e. *git* or *hg*

        ``repo``

            object from external api

        ``revisions``

            list of all available revisions' ids, in ascending order

        ``changesets``

            storage dict caching returned changesets

        ``path``

            absolute path to the repository

        ``branches``

            branches as list of changesets

        ``tags``

            tags as list of changesets

    """

    scm = None

    DEFAULT_BRANCH_NAME = None

    EMPTY_CHANGESET = '0' * 40

    def __init__(self, repo_path, create=False, **kwargs):

        """

        Initializes repository. Raises RepositoryError if repository could

        not be find at the given ``repo_path`` or directory at ``repo_path``

        exists and ``create`` is set to True.

        :param repo_path: local path of the repository

        :param create=False: if set to True, would try to craete repository.

        :param src_url=None: if set, should be proper url from which repository

          would be cloned; requires ``create`` parameter to be set to True -

          raises RepositoryError if src_url is set and create evaluates to

          False

        """

        raise NotImplementedError

    def __str__(self):

        return '<%s at %s>' % (self.__class__.__name__, self.path)

    def __repr__(self):

        return self.__str__()

    def __len__(self):

        return self.count()

    def __eq__(self, other):

        same_instance = isinstance(other, self.__class__)

        return same_instance and getattr(other, 'path', None) == self.path

    @LazyProperty

    def alias(self):

        for k, v in settings.BACKENDS.items():

            if v.split('.')[-1] == str(self.__class__.__name__):

                return k

    @LazyProperty

    def name(self):

        raise NotImplementedError

    @LazyProperty

    def owner(self):

        raise NotImplementedError

    @LazyProperty

    def description(self):

        raise NotImplementedError

    @LazyProperty

    def size(self):

        """

        Returns combined size in bytes for all repository files

        """

        size = 0

        try:

            tip = self.get_changeset()

            for topnode, dirs, files in tip.walk('/'):

                for f in files:

                    size += tip.get_file_size(f.path)

                for dir in dirs:

                    for f in files:

                        size += tip.get_file_size(f.path)

        except RepositoryError, e:

            pass

        return size

    def is_valid(self):

        """

        Validates repository.

        """

        raise NotImplementedError

    def get_last_change(self):

        self.get_changesets()

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

    # CHANGESETS

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

    def get_changeset(self, revision=None):

        """

        Returns instance of ``Changeset`` class. If ``revision`` is None, most

        recent changeset is returned.

        :raises ``EmptyRepositoryError``: if there are no revisions

        """

        raise NotImplementedError

    def __iter__(self):

        """

        Allows Repository objects to be iterated.

        *Requires* implementation of ``__getitem__`` method.

        """

        for revision in self.revisions:

            yield self.get_changeset(revision)

    def get_changesets(self, start=None, end=None, start_date=None,

                       end_date=None, branch_name=None, reverse=False):

        """

        Returns iterator of ``MercurialChangeset`` objects from start to end

        not inclusive This should behave just like a list, ie. end is not

        inclusive

        :param start: None or str

        :param end: None or str

        :param start_date:

        :param end_date:

        :param branch_name:

        :param reversed:

        """

        raise NotImplementedError

    def __getslice__(self, i, j):

        """

        Returns a iterator of sliced repository

        """

        for rev in self.revisions[i:j]:

            yield self.get_changeset(rev)

    def __getitem__(self, key):

        return self.get_changeset(key)

    def count(self):