import os

import time

import datetime

import urllib

import urllib2

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

from .workdir import MercurialWorkdir

from .changeset import MercurialChangeset

from .inmemory import MercurialInMemoryChangeset

from rhodecode.lib.vcs.exceptions import BranchDoesNotExistError, \

    ChangesetDoesNotExistError, EmptyRepositoryError, RepositoryError, \

    VCSError, TagAlreadyExistError, TagDoesNotExistError

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

    makedate, safe_unicode

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

from rhodecode.lib.vcs.utils.ordered_dict import OrderedDict

from rhodecode.lib.vcs.utils.paths import abspath

class MercurialRepository(BaseRepository):

    """

    Mercurial repository backend

    """

    DEFAULT_BRANCH_NAME = 'default'

    scm = 'hg'

    def __init__(self, repo_path, create=False, baseui=None, src_url=None,

                 update_after_clone=False):

        """

        Raises RepositoryError if repository could not be find at the given

        ``repo_path``.

        :param repo_path: local path of the repository

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

           it does not exist rather than raising exception

        :param baseui=None: user data

        :param src_url=None: would try to clone repository from given location

        :param update_after_clone=False: sets update of working copy after

          making a clone

        """

        if not isinstance(repo_path, str):

            raise VCSError('Mercurial backend requires repository path to '

                           'be instance of <str> got %s instead' %

                           type(repo_path))

        self.path = abspath(repo_path)

        self.baseui = baseui or ui.ui()

        # We've set path and ui, now we can set _repo itself

        self._repo = self._get_repo(create, src_url, update_after_clone)

    @property

    def _empty(self):

        """

        Checks if repository is empty without any changesets

        """

        # TODO: Following raises errors when using InMemoryChangeset...

        # return len(self._repo.changelog) == 0

        return len(self.revisions) == 0

    @LazyProperty

    def revisions(self):

        """

        Returns list of revisions' ids, in ascending order.  Being lazy

        attribute allows external tools to inject shas from cache.

        url = str(url)

        if url != 'default' and not '://' in url:

            url = "file:" + urllib.pathname2url(url)

        return url

    def get_hook_location(self):

        """

        returns absolute path to location where hooks are stored

        """

        return os.path.join(self.path, '.hg', '.hgrc')

    def get_changeset(self, revision=None):

        """

        Returns ``MercurialChangeset`` object representing repository's

        changeset at the given ``revision``.

        """

        revision = self._get_revision(revision)

        changeset = MercurialChangeset(repository=self, revision=revision)

        return changeset

    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

        (both are inclusive)

        :param start: None, str, int or mercurial lookup format

        :param end:  None, str, int or mercurial lookup format

        :param start_date:

        :param end_date:

        :param branch_name:

        :param reversed: return changesets in reversed order

        """

        start_raw_id = self._get_revision(start)

        start_pos = self.revisions.index(start_raw_id) if start else None

        end_raw_id = self._get_revision(end)

        end_pos = self.revisions.index(end_raw_id) if end else None

        if None not in [start, end] and start_pos > end_pos:

            raise RepositoryError("Start revision '%s' cannot be "

                                  "after end revision '%s'" % (start, end))

        if branch_name and branch_name not in self.allbranches.keys():

            raise BranchDoesNotExistError('Branch %s not found in'

                                  ' this repository' % branch_name)

        if end_pos is not None:

            end_pos += 1

        for id_ in slice_:

            cs = self.get_changeset(id_)

            if start_date and cs.date < start_date:

                continue

            if end_date and cs.date > end_date:

                continue

            yield cs

    def pull(self, url):

        """

        Tries to pull changes from external location.

        """

        url = self._get_url(url)

        try:

            pull(self.baseui, self._repo, url)

        except Abort, err:

            # Propagate error but with vcs's type

            raise RepositoryError(str(err))

    @LazyProperty

    def workdir(self):

        """

        Returns ``Workdir`` instance for this repository.

        """

        return MercurialWorkdir(self)

    def get_config_value(self, section, name=None, config_file=None):

        """

        Returns configuration value for a given [``section``] and ``name``.

        :param section: Section we want to retrieve value from

        :param name: Name of configuration we want to retrieve

        :param config_file: A path to file which should be used to retrieve

          configuration from (might also be a list of file paths)

        """

        if config_file is None:

            config_file = []

        elif isinstance(config_file, basestring):

            config_file = [config_file]

        config = self._repo.ui

        for path in config_file:

            config.readconfig(path)

        return config.config(section, name)

    def get_user_name(self, config_file=None):

        """

        Returns user's name from global configuration file.