# -*- 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.model.pull_request

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

pull request model 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: Jun 6, 2012

:author: marcink

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

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

"""

import logging

import datetime

import re

from tg import request

from tg.i18n import ugettext as _

from sqlalchemy.orm import joinedload

from kallithea.model.meta import Session

from kallithea.lib import helpers as h

from kallithea.model.db import PullRequest, PullRequestReviewer, Notification, \

    ChangesetStatus, User

from kallithea.model.notification import NotificationModel

log = logging.getLogger(__name__)

def _assert_valid_reviewers(seq):

    """Sanity check: elements are actual User objects, and not the default user."""

    assert not any(user.is_default_user for user in seq)

class PullRequestModel(object):

    def add_reviewers(self, user, pr, reviewers, mention_recipients=None):

        """Add reviewer and send notification to them.

        """

        reviewers = set(reviewers)

        _assert_valid_reviewers(reviewers)

        if mention_recipients is not None:

            mention_recipients = set(mention_recipients) - reviewers

            _assert_valid_reviewers(mention_recipients)

        #members

        for reviewer in reviewers:

            prr = PullRequestReviewer(reviewer, pr)

            Session().add(prr)

        #notification to reviewers

        pr_url = pr.url(canonical=True)

        threading = ['%s-pr-%s@%s' % (pr.other_repo.repo_name,

                                      pr.pull_request_id,

                                      h.canonical_hostname())]

        subject = safe_unicode(

            h.link_to(

              _('%(user)s wants you to review pull request %(pr_nice_id)s: %(pr_title)s') % \

                {'user': user.username,

                 'pr_title': pr.title,

                 'pr_nice_id': pr.nice_id()},

                pr_url)

            )

        body = pr.description

        _org_ref_type, org_ref_name, _org_rev = pr.org_ref.split(':')

        _other_ref_type, other_ref_name, _other_rev = pr.other_ref.split(':')

        revision_data = [(x.raw_id, x.message)

                         for x in map(pr.org_repo.get_changeset, pr.revisions)]

        email_kwargs = {

            'pr_title': pr.title,

            'pr_title_short': h.shorter(pr.title, 50),

            'pr_user_created': user.full_name_and_username,

            'repo_name': pr.other_repo.repo_name,

            'org_repo_name': pr.org_repo.repo_name,

            'pr_nice_id': pr.nice_id(),

            'pr_target_repo': h.canonical_url('summary_home',

                               repo_name=pr.other_repo.repo_name),

            'pr_target_branch': other_ref_name,

            'pr_source_repo': h.canonical_url('summary_home',

                               repo_name=pr.org_repo.repo_name),

            'pr_source_branch': org_ref_name,

            'pr_owner': pr.owner,

            'pr_owner_username': pr.owner.username,

            'pr_username': user.username,

            'threading': threading,

            'is_mention': False,

            }

        if reviewers:

            NotificationModel().create(created_by=user, subject=subject, body=body,

                                       recipients=reviewers,

                                       type_=Notification.TYPE_PULL_REQUEST,

                                       email_kwargs=email_kwargs)

        if mention_recipients:

            email_kwargs['is_mention'] = True

            subject = _('[Mention]') + ' ' + subject

            # FIXME: this subject is wrong and unused!

            NotificationModel().create(created_by=user, subject=subject, body=body,

                                       recipients=mention_recipients,

                                       type_=Notification.TYPE_PULL_REQUEST,

                                       email_kwargs=email_kwargs)

    def mention_from_description(self, user, pr, old_description=''):

        mention_recipients = (extract_mentioned_users(pr.description) -

                              extract_mentioned_users(old_description))

        log.debug("Mentioning %s", mention_recipients)

        self.add_reviewers(user, pr, set(), mention_recipients)

    def remove_reviewers(self, user, pull_request, reviewers):

        """Remove specified users from being reviewers of the PR."""

        PullRequestReviewer.query() \

            .filter_by(pull_request=pull_request) \

            .filter(PullRequestReviewer.user_id.in_(r.user_id for r in reviewers)) \

            .delete(synchronize_session='fetch') # the default of 'evaluate' is not available

    def delete(self, pull_request):

        pull_request = PullRequest.guess_instance(pull_request)

        Session().delete(pull_request)

    def close_pull_request(self, pull_request):

        pull_request = PullRequest.guess_instance(pull_request)

        pull_request.status = PullRequest.STATUS_CLOSED

        pull_request.updated_on = datetime.datetime.now()

class CreatePullRequestAction(object):

    class ValidationError(Exception):

        pass

    class Empty(ValidationError):

        pass

    class AmbiguousAncestor(ValidationError):

        pass

    class Unauthorized(ValidationError):

        pass

    @staticmethod

    def is_user_authorized(org_repo, other_repo):

        """Performs authorization check with only the minimum amount of

        information needed for such a check, rather than a full command

        object.

        """

        if (h.HasRepoPermissionLevel('read')(org_repo.repo_name) and

            h.HasRepoPermissionLevel('read')(other_repo.repo_name)):

            return True

        return False

    def __init__(self, org_repo, other_repo, org_ref, other_ref, title, description, owner, reviewers):

        from kallithea.controllers.compare import CompareController

        reviewers = set(reviewers)

        _assert_valid_reviewers(reviewers)

        (org_ref_type,

         org_ref_name,

         org_rev) = org_ref.split(':')

        org_display = h.short_ref(org_ref_type, org_ref_name)

        if org_ref_type == 'rev':

            cs = org_repo.scm_instance.get_changeset(org_rev)

            org_ref = 'branch:%s:%s' % (cs.branch, cs.raw_id)

        (other_ref_type,

         other_ref_name,

         other_rev) = other_ref.split(':')

        if other_ref_type == 'rev':

            cs = other_repo.scm_instance.get_changeset(other_rev)

            other_ref_name = cs.raw_id[:12]

            other_ref = '%s:%s:%s' % (other_ref_type, other_ref_name, cs.raw_id)

        other_display = h.short_ref(other_ref_type, other_ref_name)

        cs_ranges, _cs_ranges_not, ancestor_revs = \

            CompareController._get_changesets(org_repo.scm_instance.alias,

                                              other_repo.scm_instance, other_rev, # org and other "swapped"

                                              org_repo.scm_instance, org_rev,

                                              )

        if not cs_ranges:

            raise self.Empty(_('Cannot create empty pull request'))

        if not ancestor_revs:

            ancestor_rev = org_repo.scm_instance.EMPTY_CHANGESET

        elif len(ancestor_revs) == 1:

            ancestor_rev = ancestor_revs[0]

        else:

            raise self.AmbiguousAncestor(

                _('Cannot create pull request - criss cross merge detected, please merge a later %s revision to %s')

                % (other_ref_name, org_ref_name))

        self.revisions = [cs_.raw_id for cs_ in cs_ranges]

        # hack: ancestor_rev is not an other_rev but we want to show the

        # requested destination and have the exact ancestor

        other_ref = '%s:%s:%s' % (other_ref_type, other_ref_name, ancestor_rev)

        if not title:

            if org_repo == other_repo:

                title = '%s to %s' % (org_display, other_display)

            else:

                title = '%s#%s to %s#%s' % (org_repo.repo_name, org_display,

                                            other_repo.repo_name, other_display)

        description = description or _('No description')

        self.org_repo = org_repo

        self.other_repo = other_repo

        self.org_ref = org_ref

        self.other_ref = other_ref

        self.title = title

        self.description = description

        self.owner = owner

        self.reviewers = reviewers

        if not CreatePullRequestAction.is_user_authorized(self.org_repo, self.other_repo):

            raise self.Unauthorized(_('You are not authorized to create the pull request'))

    def execute(self):

        created_by = User.get(request.authuser.user_id)

        pr = PullRequest()

        pr.org_repo = self.org_repo

        pr.org_ref = self.org_ref

        pr.other_repo = self.other_repo

        pr.other_ref = self.other_ref

        pr.revisions = self.revisions

        pr.title = self.title

        pr.description = self.description

        pr.owner = self.owner

        Session().add(pr)

        Session().flush() # make database assign pull_request_id

        #reset state to under-review

        from kallithea.model.changeset_status import ChangesetStatusModel

        from kallithea.model.comment import ChangesetCommentsModel

        comment = ChangesetCommentsModel().create(

            text=u'',

            repo=self.org_repo,

            author=created_by,

            pull_request=pr,

            send_email=False,

            status_change=ChangesetStatus.STATUS_UNDER_REVIEW,

        )

        ChangesetStatusModel().set_status(

            self.org_repo,

            ChangesetStatus.STATUS_UNDER_REVIEW,

            created_by,

            comment,

            pull_request=pr,

        )

        mention_recipients = extract_mentioned_users(self.description)

        PullRequestModel().add_reviewers(created_by, pr, self.reviewers, mention_recipients)

        return pr

class CreatePullRequestIterationAction(object):

    @staticmethod

    def is_user_authorized(old_pull_request):

        """Performs authorization check with only the minimum amount of

        information needed for such a check, rather than a full command

        object.

        """

        if h.HasPermissionAny('hg.admin')():

            return True

        # Authorized to edit the old PR?

        if request.authuser.user_id != old_pull_request.owner_id:

            return False

        # Authorized to create a new PR?

        if not CreatePullRequestAction.is_user_authorized(old_pull_request.org_repo, old_pull_request.other_repo):

            return False

        return True

    def __init__(self, old_pull_request, new_org_rev, new_other_rev, title, description, owner, reviewers):

        self.old_pull_request = old_pull_request