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

# Copyright (C) 2010-2020 RhodeCode GmbH
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License, version 3
# (only), as published by the Free Software Foundation.
#
# 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 Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# This program is dual-licensed. If you wish to learn more about the
# RhodeCode Enterprise Edition, including its added features, Support services,
# and proprietary license terms, please see https://rhodecode.com/licenses/

"""
Scm model for RhodeCode
"""

import os.path
import traceback
import logging
from io import StringIO

from sqlalchemy import func
from zope.cachedescriptors.property import Lazy as LazyProperty

import rhodecode
from rhodecode.lib.vcs import get_backend
from rhodecode.lib.vcs.exceptions import RepositoryError, NodeNotChangedError
from rhodecode.lib.vcs.nodes import FileNode
from rhodecode.lib.vcs.backends.base import EmptyCommit
from rhodecode.lib import helpers as h, rc_cache
from rhodecode.lib.auth import (
    HasRepoPermissionAny, HasRepoGroupPermissionAny,
    HasUserGroupPermissionAny)
from rhodecode.lib.exceptions import NonRelativePathError, IMCCommitError
from rhodecode.lib import hooks_utils
from rhodecode.lib.utils import (
    get_filesystem_repos, make_db_config)
from rhodecode.lib.utils2 import (safe_str, safe_unicode)
from rhodecode.lib.system_info import get_system_info
from rhodecode.model import BaseModel
from rhodecode.model.db import (
    or_, false,
    Repository, CacheKey, UserFollowing, UserLog, User, RepoGroup,
    PullRequest, FileStore)
from rhodecode.model.settings import VcsSettingsModel
from rhodecode.model.validation_schema.validators import url_validator, InvalidCloneUrl

log = logging.getLogger(__name__)


class UserTemp(object):
    def __init__(self, user_id):
        self.user_id = user_id

    def __repr__(self):
        return "<%s('id:%s')>" % (self.__class__.__name__, self.user_id)


class RepoTemp(object):
    def __init__(self, repo_id):
        self.repo_id = repo_id

    def __repr__(self):
        return "<%s('id:%s')>" % (self.__class__.__name__, self.repo_id)


class SimpleCachedRepoList(object):
    """
    Lighter version of of iteration of repos without the scm initialisation,
    and with cache usage
    """
    def __init__(self, db_repo_list, repos_path, order_by=None, perm_set=None):
        self.db_repo_list = db_repo_list
        self.repos_path = repos_path
        self.order_by = order_by
        self.reversed = (order_by or '').startswith('-')
        if not perm_set:
            perm_set = ['repository.read', 'repository.write',
                        'repository.admin']
        self.perm_set = perm_set

    def __len__(self):
        return len(self.db_repo_list)

    def __repr__(self):
        return '<%s (%s)>' % (self.__class__.__name__, self.__len__())

    def __iter__(self):
        for dbr in self.db_repo_list:
            # check permission at this level
            has_perm = HasRepoPermissionAny(*self.perm_set)(
                dbr.repo_name, 'SimpleCachedRepoList check')
            if not has_perm:
                continue

            tmp_d = {
                'name': dbr.repo_name,
                'dbrepo': dbr.get_dict(),
                'dbrepo_fork': dbr.fork.get_dict() if dbr.fork else {}
            }
            yield tmp_d


class _PermCheckIterator(object):

    def __init__(
            self, obj_list, obj_attr, perm_set, perm_checker,
            extra_kwargs=None):
        """
        Creates iterator from given list of objects, additionally
        checking permission for them from perm_set var

        :param obj_list: list of db objects
        :param obj_attr: attribute of object to pass into perm_checker
        :param perm_set: list of permissions to check
        :param perm_checker: callable to check permissions against
        """
        self.obj_list = obj_list
        self.obj_attr = obj_attr
        self.perm_set = perm_set
        self.perm_checker = perm_checker(*self.perm_set)
        self.extra_kwargs = extra_kwargs or {}

    def __len__(self):
        return len(self.obj_list)

    def __repr__(self):
        return '<%s (%s)>' % (self.__class__.__name__, self.__len__())

    def __iter__(self):
        for db_obj in self.obj_list:
            # check permission at this level
            # NOTE(marcink): the __dict__.get() is ~4x faster then getattr()
            name = db_obj.__dict__.get(self.obj_attr, None)
            if not self.perm_checker(name, self.__class__.__name__, **self.extra_kwargs):
                continue

            yield db_obj


class RepoList(_PermCheckIterator):

    def __init__(self, db_repo_list, perm_set=None, extra_kwargs=None):
        if not perm_set:
            perm_set = ['repository.read', 'repository.write', 'repository.admin']

        super(RepoList, self).__init__(
            obj_list=db_repo_list,
            obj_attr='_repo_name', perm_set=perm_set,
            perm_checker=HasRepoPermissionAny,
            extra_kwargs=extra_kwargs)


class RepoGroupList(_PermCheckIterator):

    def __init__(self, db_repo_group_list, perm_set=None, extra_kwargs=None):
        if not perm_set:
            perm_set = ['group.read', 'group.write', 'group.admin']

        super(RepoGroupList, self).__init__(
            obj_list=db_repo_group_list,
            obj_attr='_group_name', perm_set=perm_set,
            perm_checker=HasRepoGroupPermissionAny,
            extra_kwargs=extra_kwargs)


class UserGroupList(_PermCheckIterator):

    def __init__(self, db_user_group_list, perm_set=None, extra_kwargs=None):
        if not perm_set:
            perm_set = ['usergroup.read', 'usergroup.write', 'usergroup.admin']

        super(UserGroupList, self).__init__(
            obj_list=db_user_group_list,
            obj_attr='users_group_name', perm_set=perm_set,
            perm_checker=HasUserGroupPermissionAny,
            extra_kwargs=extra_kwargs)


class ScmModel(BaseModel):
    """
    Generic Scm Model
    """

    @LazyProperty
    def repos_path(self):
        """
        Gets the repositories root path from database
        """

        settings_model = VcsSettingsModel(sa=self.sa)
        return settings_model.get_repos_location()

    def repo_scan(self, repos_path=None):
        """
        Listing of repositories in given path. This path should not be a
        repository itself. Return a dictionary of repository objects

        :param repos_path: path to directory containing repositories
        """

        if repos_path is None:
            repos_path = self.repos_path

        log.info('scanning for repositories in %s', repos_path)

        config = make_db_config()
        config.set('extensions', 'largefiles', '')
        repos = {}

        for name, path in get_filesystem_repos(repos_path, recursive=True):
            # name need to be decomposed and put back together using the /
            # since this is internal storage separator for rhodecode
            name = Repository.normalize_repo_name(name)

            try:
                if name in repos:
                    raise RepositoryError('Duplicate repository name %s '
                                          'found in %s' % (name, path))
                elif path[0] in rhodecode.BACKENDS:
                    backend = get_backend(path[0])
                    repos[name] = backend(path[1], config=config,
                                          with_wire={"cache": False})
            except OSError:
                continue
            except RepositoryError:
                log.exception('Failed to create a repo')
                continue

        log.debug('found %s paths with repositories', len(repos))
        return repos

    def get_repos(self, all_repos=None, sort_key=None):
        """
        Get all repositories from db and for each repo create it's
        backend instance and fill that backed with information from database

        :param all_repos: list of repository names as strings
            give specific repositories list, good for filtering

        :param sort_key: initial sorting of repositories
        """
        if all_repos is None:
            all_repos = self.sa.query(Repository)\
                .filter(Repository.group_id == None)\
                .order_by(func.lower(Repository.repo_name)).all()
        repo_iter = SimpleCachedRepoList(
            all_repos, repos_path=self.repos_path, order_by=sort_key)
        return repo_iter

    def get_repo_groups(self, all_groups=None):
        if all_groups is None:
            all_groups = RepoGroup.query()\
                .filter(RepoGroup.group_parent_id == None).all()
        return [x for x in RepoGroupList(all_groups)]

    def mark_for_invalidation(self, repo_name, delete=False):
        """
        Mark caches of this repo invalid in the database. `delete` flag
        removes the cache entries

        :param repo_name: the repo_name for which caches should be marked
            invalid, or deleted
        :param delete: delete the entry keys instead of setting bool
            flag on them, and also purge caches used by the dogpile
        """
        repo = Repository.get_by_repo_name(repo_name)

        if repo:
            invalidation_namespace = CacheKey.REPO_INVALIDATION_NAMESPACE.format(
                repo_id=repo.repo_id)
            CacheKey.set_invalidate(invalidation_namespace, delete=delete)

            repo_id = repo.repo_id
            config = repo._config
            config.set('extensions', 'largefiles', '')
            repo.update_commit_cache(config=config, cs_cache=None)
            if delete:
                cache_namespace_uid = 'cache_repo.{}'.format(repo_id)
                rc_cache.clear_cache_namespace(
                    'cache_repo', cache_namespace_uid, invalidate=True)

    def toggle_following_repo(self, follow_repo_id, user_id):

        f = self.sa.query(UserFollowing)\
            .filter(UserFollowing.follows_repo_id == follow_repo_id)\
            .filter(UserFollowing.user_id == user_id).scalar()

        if f is not None:
            try:
                self.sa.delete(f)
                return
            except Exception:
                log.error(traceback.format_exc())
                raise

        try:
            f = UserFollowing()
            f.user_id = user_id
            f.follows_repo_id = follow_repo_id
            self.sa.add(f)
        except Exception:
            log.error(traceback.format_exc())
            raise

    def toggle_following_user(self, follow_user_id, user_id):
        f = self.sa.query(UserFollowing)\
            .filter(UserFollowing.follows_user_id == follow_user_id)\
            .filter(UserFollowing.user_id == user_id).scalar()

        if f is not None:
            try:
                self.sa.delete(f)
                return
            except Exception:
                log.error(traceback.format_exc())
                raise

        try:
            f = UserFollowing()
            f.user_id = user_id
            f.follows_user_id = follow_user_id
            self.sa.add(f)
        except Exception:
            log.error(traceback.format_exc())
            raise

    def is_following_repo(self, repo_name, user_id, cache=False):
        r = self.sa.query(Repository)\
            .filter(Repository.repo_name == repo_name).scalar()

        f = self.sa.query(UserFollowing)\
            .filter(UserFollowing.follows_repository == r)\
            .filter(UserFollowing.user_id == user_id).scalar()

        return f is not None

    def is_following_user(self, username, user_id, cache=False):
        u = User.get_by_username(username)

        f = self.sa.query(UserFollowing)\
            .filter(UserFollowing.follows_user == u)\
            .filter(UserFollowing.user_id == user_id).scalar()

        return f is not None

    def get_followers(self, repo):
        repo = self._get_repo(repo)

        return self.sa.query(UserFollowing)\
            .filter(UserFollowing.follows_repository == repo).count()

    def get_forks(self, repo):
        repo = self._get_repo(repo)
        return self.sa.query(Repository)\
            .filter(Repository.fork == repo).count()

    def get_pull_requests(self, repo):
        repo = self._get_repo(repo)
        return self.sa.query(PullRequest)\
            .filter(PullRequest.target_repo == repo)\
            .filter(PullRequest.status != PullRequest.STATUS_CLOSED).count()

    def get_artifacts(self, repo):
        repo = self._get_repo(repo)
        return self.sa.query(FileStore)\
            .filter(FileStore.repo == repo)\
            .filter(or_(FileStore.hidden == None, FileStore.hidden == false())).count()

    def mark_as_fork(self, repo, fork, user):
        repo = self._get_repo(repo)
        fork = self._get_repo(fork)
        if fork and repo.repo_id == fork.repo_id:
            raise Exception("Cannot set repository as fork of itself")

        if fork and repo.repo_type != fork.repo_type:
            raise RepositoryError(
                "Cannot set repository as fork of repository with other type")

        repo.fork = fork
        self.sa.add(repo)
        return repo

    def pull_changes(self, repo, username, remote_uri=None, validate_uri=True):
        dbrepo = self._get_repo(repo)
        remote_uri = remote_uri or dbrepo.clone_uri
        if not remote_uri:
            raise Exception("This repository doesn't have a clone uri")

        repo = dbrepo.scm_instance(cache=False)
        repo.config.clear_section('hooks')

        try:
            # NOTE(marcink): add extra validation so we skip invalid urls
            # this is due this tasks can be executed via scheduler without
            # proper validation of remote_uri
            if validate_uri:
                config = make_db_config(clear_session=False)
                url_validator(remote_uri, dbrepo.repo_type, config)
        except InvalidCloneUrl:
            raise

        repo_name = dbrepo.repo_name
        try:
            # TODO: we need to make sure those operations call proper hooks !
            repo.fetch(remote_uri)

            self.mark_for_invalidation(repo_name)
        except Exception:
            log.error(traceback.format_exc())
            raise

    def push_changes(self, repo, username, remote_uri=None, validate_uri=True):
        dbrepo = self._get_repo(repo)
        remote_uri = remote_uri or dbrepo.push_uri
        if not remote_uri:
            raise Exception("This repository doesn't have a clone uri")

        repo = dbrepo.scm_instance(cache=False)
        repo.config.clear_section('hooks')

        try:
            # NOTE(marcink): add extra validation so we skip invalid urls
            # this is due this tasks can be executed via scheduler without
            # proper validation of remote_uri
            if validate_uri:
                config = make_db_config(clear_session=False)
                url_validator(remote_uri, dbrepo.repo_type, config)
        except InvalidCloneUrl:
            raise

        try:
            repo.push(remote_uri)
        except Exception:
            log.error(traceback.format_exc())
            raise

    def commit_change(self, repo, repo_name, commit, user, author, message,
                      content, f_path):
        """
        Commits changes

        :param repo: SCM instance

        """
        user = self._get_user(user)

        # decoding here will force that we have proper encoded values
        # in any other case this will throw exceptions and deny commit
        content = safe_str(content)
        path = safe_str(f_path)
        # message and author needs to be unicode
        # proper backend should then translate that into required type
        message = safe_unicode(message)
        author = safe_unicode(author)
        imc = repo.in_memory_commit
        imc.change(FileNode(path, content, mode=commit.get_file_mode(f_path)))
        try:
            # TODO: handle pre-push action !
            tip = imc.commit(
                message=message, author=author, parents=[commit],
                branch=commit.branch)
        except Exception as e:
            log.error(traceback.format_exc())
            raise IMCCommitError(str(e))
        finally:
            # always clear caches, if commit fails we want fresh object also
            self.mark_for_invalidation(repo_name)

        # We trigger the post-push action
        hooks_utils.trigger_post_push_hook(
            username=user.username, action='push_local', hook_type='post_push',
            repo_name=repo_name, repo_type=repo.alias, commit_ids=[tip.raw_id])
        return tip

    def _sanitize_path(self, f_path):
        if f_path.startswith('/') or f_path.startswith('./') or '../' in f_path:
            raise NonRelativePathError('%s is not an relative path' % f_path)
        if f_path:
            f_path = os.path.normpath(f_path)
        return f_path

    def get_dirnode_metadata(self, request, commit, dir_node):
        if not dir_node.is_dir():
            return []

        data = []
        for node in dir_node:
            if not node.is_file():
                # we skip file-nodes
                continue

            last_commit = node.last_commit
            last_commit_date = last_commit.date
            data.append({
                'name': node.name,
                'size': h.format_byte_size_binary(node.size),
                'modified_at': h.format_date(last_commit_date),
                'modified_ts': last_commit_date.isoformat(),
                'revision': last_commit.revision,
                'short_id': last_commit.short_id,
                'message': h.escape(last_commit.message),
                'author': h.escape(last_commit.author),
                'user_profile': h.gravatar_with_user(
                    request, last_commit.author),
            })

        return data

    def get_nodes(self, repo_name, commit_id, root_path='/', flat=True,
                  extended_info=False, content=False, max_file_bytes=None):
        """
        recursive walk in root dir and return a set of all path in that dir
        based on repository walk function

        :param repo_name: name of repository
        :param commit_id: commit id for which to list nodes
        :param root_path: root path to list
        :param flat: return as a list, if False returns a dict with description
        :param extended_info: show additional info such as md5, binary, size etc
        :param content: add nodes content to the return data
        :param max_file_bytes: will not return file contents over this limit

        """
        _files = list()
        _dirs = list()
        try:
            _repo = self._get_repo(repo_name)
            commit = _repo.scm_instance().get_commit(commit_id=commit_id)
            root_path = root_path.lstrip('/')
            for __, dirs, files in commit.walk(root_path):

                for f in files:
                    _content = None
                    _data = f_name = f.unicode_path

                    if not flat:
                        _data = {
                            "name": h.escape(f_name),
                            "type": "file",
                            }
                        if extended_info:
                            _data.update({
                                "md5": f.md5,
                                "binary": f.is_binary,
                                "size": f.size,
                                "extension": f.extension,
                                "mimetype": f.mimetype,
                                "lines": f.lines()[0]
                            })

                        if content:
                            over_size_limit = (max_file_bytes is not None
                                               and f.size > max_file_bytes)
                            full_content = None
                            if not f.is_binary and not over_size_limit:
                                full_content = safe_str(f.content)

                            _data.update({
                                "content": full_content,
                            })
                    _files.append(_data)

                for d in dirs:
                    _data = d_name = d.unicode_path
                    if not flat:
                        _data = {
                            "name": h.escape(d_name),
                            "type": "dir",
                            }
                    if extended_info:
                        _data.update({
                            "md5": None,
                            "binary": None,
                            "size": None,
                            "extension": None,
                        })
                    if content:
                        _data.update({
                            "content": None
                        })
                    _dirs.append(_data)
        except RepositoryError:
            log.exception("Exception in get_nodes")
            raise

        return _dirs, _files

    def get_quick_filter_nodes(self, repo_name, commit_id, root_path='/'):
        """
        Generate files for quick filter in files view
        """

        _files = list()
        _dirs = list()
        try:
            _repo = self._get_repo(repo_name)
            commit = _repo.scm_instance().get_commit(commit_id=commit_id)
            root_path = root_path.lstrip('/')
            for __, dirs, files in commit.walk(root_path):

                for f in files:

                    _data = {
                        "name": h.escape(f.unicode_path),
                        "type": "file",
                        }

                    _files.append(_data)

                for d in dirs:

                    _data = {
                        "name": h.escape(d.unicode_path),
                        "type": "dir",
                        }

                    _dirs.append(_data)
        except RepositoryError:
            log.exception("Exception in get_quick_filter_nodes")
            raise

        return _dirs, _files

    def get_node(self, repo_name, commit_id, file_path,
                 extended_info=False, content=False, max_file_bytes=None, cache=True):
        """
        retrieve single node from commit
        """
        try:

            _repo = self._get_repo(repo_name)
            commit = _repo.scm_instance().get_commit(commit_id=commit_id)

            file_node = commit.get_node(file_path)
            if file_node.is_dir():
                raise RepositoryError('The given path is a directory')

            _content = None
            f_name = file_node.unicode_path

            file_data = {
                "name": h.escape(f_name),
                "type": "file",
            }

            if extended_info:
                file_data.update({
                    "extension": file_node.extension,
                    "mimetype": file_node.mimetype,
                })

                if cache:
                    md5 = file_node.md5
                    is_binary = file_node.is_binary
                    size = file_node.size
                else:
                    is_binary, md5, size, _content = file_node.metadata_uncached()

                file_data.update({
                    "md5": md5,
                    "binary": is_binary,
                    "size": size,
                })

            if content and cache:
                # get content + cache
                size = file_node.size
                over_size_limit = (max_file_bytes is not None and size > max_file_bytes)
                full_content = None
                all_lines = 0
                if not file_node.is_binary and not over_size_limit:
                    full_content = safe_unicode(file_node.content)
                    all_lines, empty_lines = file_node.count_lines(full_content)

                file_data.update({
                    "content": full_content,
                    "lines": all_lines
                })
            elif content:
                # get content *without* cache
                if _content is None:
                    is_binary, md5, size, _content = file_node.metadata_uncached()

                over_size_limit = (max_file_bytes is not None and size > max_file_bytes)
                full_content = None
                all_lines = 0
                if not is_binary and not over_size_limit:
                    full_content = safe_unicode(_content)
                    all_lines, empty_lines = file_node.count_lines(full_content)

                file_data.update({
                    "content": full_content,
                    "lines": all_lines
                })

        except RepositoryError:
            log.exception("Exception in get_node")
            raise

        return file_data

    def get_fts_data(self, repo_name, commit_id, root_path='/'):
        """
        Fetch node tree for usage in full text search
        """

        tree_info = list()

        try:
            _repo = self._get_repo(repo_name)
            commit = _repo.scm_instance().get_commit(commit_id=commit_id)
            root_path = root_path.lstrip('/')
            for __, dirs, files in commit.walk(root_path):

                for f in files:
                    is_binary, md5, size, _content = f.metadata_uncached()
                    _data = {
                        "name": f.unicode_path,
                        "md5": md5,
                        "extension": f.extension,
                        "binary": is_binary,
                        "size": size
                    }

                    tree_info.append(_data)

        except RepositoryError:
            log.exception("Exception in get_nodes")
            raise

        return tree_info

    def create_nodes(self, user, repo, message, nodes, parent_commit=None,
                     author=None, trigger_push_hook=True):
        """
        Commits given multiple nodes into repo

        :param user: RhodeCode User object or user_id, the commiter
        :param repo: RhodeCode Repository object
        :param message: commit message
        :param nodes: mapping {filename:{'content':content},...}
        :param parent_commit: parent commit, can be empty than it's
           initial commit
        :param author: author of commit, cna be different that commiter
           only for git
        :param trigger_push_hook: trigger push hooks

        :returns: new committed commit
        """

        user = self._get_user(user)
        scm_instance = repo.scm_instance(cache=False)

        processed_nodes = []
        for f_path in nodes:
            f_path = self._sanitize_path(f_path)
            content = nodes[f_path]['content']
            f_path = safe_str(f_path)
            # decoding here will force that we have proper encoded values
            # in any other case this will throw exceptions and deny commit
            if isinstance(content, (str,)):
                content = safe_str(content)
            elif isinstance(content, (file, cStringIO.OutputType,)):
                content = content.read()
            else:
                raise Exception('Content is of unrecognized type %s' % (
                    type(content)
                ))
            processed_nodes.append((f_path, content))

        message = safe_unicode(message)
        commiter = user.full_contact
        author = safe_unicode(author) if author else commiter

        imc = scm_instance.in_memory_commit

        if not parent_commit:
            parent_commit = EmptyCommit(alias=scm_instance.alias)

        if isinstance(parent_commit, EmptyCommit):
            # EmptyCommit means we we're editing empty repository
            parents = None
        else:
            parents = [parent_commit]
        # add multiple nodes
        for path, content in processed_nodes:
            imc.add(FileNode(path, content=content))
        # TODO: handle pre push scenario
        tip = imc.commit(message=message,
                         author=author,
                         parents=parents,
                         branch=parent_commit.branch)

        self.mark_for_invalidation(repo.repo_name)
        if trigger_push_hook:
            hooks_utils.trigger_post_push_hook(
                username=user.username, action='push_local',
                repo_name=repo.repo_name, repo_type=scm_instance.alias,
                hook_type='post_push',
                commit_ids=[tip.raw_id])
        return tip

    def update_nodes(self, user, repo, message, nodes, parent_commit=None,
                     author=None, trigger_push_hook=True):
        user = self._get_user(user)
        scm_instance = repo.scm_instance(cache=False)

        message = safe_unicode(message)
        commiter = user.full_contact
        author = safe_unicode(author) if author else commiter

        imc = scm_instance.in_memory_commit

        if not parent_commit:
            parent_commit = EmptyCommit(alias=scm_instance.alias)

        if isinstance(parent_commit, EmptyCommit):
            # EmptyCommit means we we're editing empty repository
            parents = None
        else:
            parents = [parent_commit]

        # add multiple nodes
        for _filename, data in nodes.items():
            # new filename, can be renamed from the old one, also sanitaze
            # the path for any hack around relative paths like ../../ etc.
            filename = self._sanitize_path(data['filename'])
            old_filename = self._sanitize_path(_filename)
            content = data['content']
            file_mode = data.get('mode')
            filenode = FileNode(old_filename, content=content, mode=file_mode)
            op = data['op']
            if op == 'add':
                imc.add(filenode)
            elif op == 'del':
                imc.remove(filenode)
            elif op == 'mod':
                if filename != old_filename:
                    # TODO: handle renames more efficient, needs vcs lib changes
                    imc.remove(filenode)
                    imc.add(FileNode(filename, content=content, mode=file_mode))
                else:
                    imc.change(filenode)

        try:
            # TODO: handle pre push scenario commit changes
            tip = imc.commit(message=message,
                             author=author,
                             parents=parents,
                             branch=parent_commit.branch)
        except NodeNotChangedError:
            raise
        except Exception as e:
            log.exception("Unexpected exception during call to imc.commit")
            raise IMCCommitError(str(e))
        finally:
            # always clear caches, if commit fails we want fresh object also
            self.mark_for_invalidation(repo.repo_name)

        if trigger_push_hook:
            hooks_utils.trigger_post_push_hook(
                username=user.username, action='push_local', hook_type='post_push',
                repo_name=repo.repo_name, repo_type=scm_instance.alias,
                commit_ids=[tip.raw_id])

        return tip

    def delete_nodes(self, user, repo, message, nodes, parent_commit=None,
                     author=None, trigger_push_hook=True):
        """
        Deletes given multiple nodes into `repo`

        :param user: RhodeCode User object or user_id, the committer
        :param repo: RhodeCode Repository object
        :param message: commit message
        :param nodes: mapping {filename:{'content':content},...}
        :param parent_commit: parent commit, can be empty than it's initial
           commit
        :param author: author of commit, cna be different that commiter only
           for git
        :param trigger_push_hook: trigger push hooks

        :returns: new commit after deletion
        """

        user = self._get_user(user)
        scm_instance = repo.scm_instance(cache=False)

        processed_nodes = []
        for f_path in nodes:
            f_path = self._sanitize_path(f_path)
            # content can be empty but for compatabilty it allows same dicts
            # structure as add_nodes
            content = nodes[f_path].get('content')
            processed_nodes.append((f_path, content))

        message = safe_unicode(message)
        commiter = user.full_contact
        author = safe_unicode(author) if author else commiter

        imc = scm_instance.in_memory_commit

        if not parent_commit:
            parent_commit = EmptyCommit(alias=scm_instance.alias)

        if isinstance(parent_commit, EmptyCommit):
            # EmptyCommit means we we're editing empty repository
            parents = None
        else:
            parents = [parent_commit]
        # add multiple nodes
        for path, content in processed_nodes:
            imc.remove(FileNode(path, content=content))

        # TODO: handle pre push scenario
        tip = imc.commit(message=message,
                         author=author,
                         parents=parents,
                         branch=parent_commit.branch)

        self.mark_for_invalidation(repo.repo_name)
        if trigger_push_hook:
            hooks_utils.trigger_post_push_hook(
                username=user.username, action='push_local', hook_type='post_push',
                repo_name=repo.repo_name, repo_type=scm_instance.alias,
                commit_ids=[tip.raw_id])
        return tip

    def strip(self, repo, commit_id, branch):
        scm_instance = repo.scm_instance(cache=False)
        scm_instance.config.clear_section('hooks')
        scm_instance.strip(commit_id, branch)
        self.mark_for_invalidation(repo.repo_name)

    def get_unread_journal(self):
        return self.sa.query(UserLog).count()

    @classmethod
    def backend_landing_ref(cls, repo_type):
        """
        Return a default landing ref based on a repository type.
        """

        landing_ref = {
            'hg': ('branch:default', 'default'),
            'git': ('branch:master', 'master'),
            'svn': ('rev:tip', 'latest tip'),
            'default': ('rev:tip', 'latest tip'),
        }

        return landing_ref.get(repo_type) or landing_ref['default']

    def get_repo_landing_revs(self, translator, repo=None):
        """
        Generates select option with tags branches and bookmarks (for hg only)
        grouped by type

        :param repo:
        """
        from rhodecode.lib.vcs.backends.git import GitRepository

        _ = translator
        repo = self._get_repo(repo)

        if repo:
            repo_type = repo.repo_type
        else:
            repo_type = 'default'

        default_landing_ref, landing_ref_lbl = self.backend_landing_ref(repo_type)

        default_ref_options = [
            [default_landing_ref, landing_ref_lbl]
        ]
        default_choices = [
            default_landing_ref
        ]

        if not repo:
            # presented at NEW repo creation
            return default_choices, default_ref_options

        repo = repo.scm_instance()

        ref_options = [(default_landing_ref, landing_ref_lbl)]
        choices = [default_landing_ref]

        # branches
        branch_group = [(u'branch:%s' % safe_unicode(b), safe_unicode(b)) for b in repo.branches]
        if not branch_group:
            # new repo, or without maybe a branch?
            branch_group = default_ref_options

        branches_group = (branch_group, _("Branches"))
        ref_options.append(branches_group)
        choices.extend([x[0] for x in branches_group[0]])

        # bookmarks for HG
        if repo.alias == 'hg':
            bookmarks_group = (
                [(u'book:%s' % safe_unicode(b), safe_unicode(b))
                    for b in repo.bookmarks],
                _("Bookmarks"))
            ref_options.append(bookmarks_group)
            choices.extend([x[0] for x in bookmarks_group[0]])

        # tags
        tags_group = (
            [(u'tag:%s' % safe_unicode(t), safe_unicode(t))
                for t in repo.tags],
            _("Tags"))
        ref_options.append(tags_group)
        choices.extend([x[0] for x in tags_group[0]])

        return choices, ref_options

    def get_server_info(self, environ=None):
        server_info = get_system_info(environ)
        return server_info