# -*- 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.controllers.pullrequests
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

pull requests controller for rhodecode for initializing pull requests

:created_on: May 7, 2012
:author: marcink
:copyright: (c) 2013 RhodeCode GmbH.
:license: GPLv3, see LICENSE.md for more details.
"""

import logging
import traceback
import formencode

from webob.exc import HTTPNotFound, HTTPForbidden
from collections import defaultdict
from itertools import groupby

from pylons import request, tmpl_context as c, url
from pylons.controllers.util import redirect
from pylons.i18n.translation import _

from kallithea.lib.compat import json
from kallithea.lib.base import BaseRepoController, render
from kallithea.lib.auth import LoginRequired, HasRepoPermissionAnyDecorator,\
    NotAnonymous
from kallithea.lib.helpers import Page
from kallithea.lib import helpers as h
from kallithea.lib import diffs
from kallithea.lib.utils import action_logger, jsonify
from kallithea.lib.vcs.utils import safe_str
from kallithea.lib.vcs.exceptions import EmptyRepositoryError
from kallithea.lib.diffs import LimitedDiffContainer
from kallithea.model.db import  PullRequest, ChangesetStatus, ChangesetComment
from kallithea.model.pull_request import PullRequestModel
from kallithea.model.meta import Session
from kallithea.model.repo import RepoModel
from kallithea.model.comment import ChangesetCommentsModel
from kallithea.model.changeset_status import ChangesetStatusModel
from kallithea.model.forms import PullRequestForm
from kallithea.lib.utils2 import safe_int

log = logging.getLogger(__name__)


class PullrequestsController(BaseRepoController):

    def __before__(self):
        super(PullrequestsController, self).__before__()
        repo_model = RepoModel()
        c.users_array = repo_model.get_users_js()
        c.user_groups_array = repo_model.get_user_groups_js()

    def _get_repo_refs(self, repo, rev=None, branch=None, branch_rev=None):
        """return a structure with repo's interesting changesets, suitable for
        the selectors in pullrequest.html

        rev: a revision that must be in the list somehow and selected by default
        branch: a branch that must be in the list and selected by default - even if closed
        branch_rev: a revision of which peers should be preferred and available."""
        # list named branches that has been merged to this named branch - it should probably merge back
        peers = []

        if rev:
            rev = safe_str(rev)

        if branch:
            branch = safe_str(branch)

        if branch_rev:
            branch_rev = safe_str(branch_rev)
            # not restricting to merge() would also get branch point and be better
            # (especially because it would get the branch point) ... but is currently too expensive
            otherbranches = {}
            for i in repo._repo.revs(
                "sort(parents(branch(id(%s)) and merge()) - branch(id(%s)))",
                branch_rev, branch_rev):
                cs = repo.get_changeset(i)
                otherbranches[cs.branch] = cs.raw_id
            for abranch, node in otherbranches.iteritems():
                selected = 'branch:%s:%s' % (abranch, node)
                peers.append((selected, abranch))

        selected = None

        branches = []
        for abranch, branchrev in repo.branches.iteritems():
            n = 'branch:%s:%s' % (abranch, branchrev)
            branches.append((n, abranch))
            if rev == branchrev:
                selected = n
            if branch == abranch:
                selected = n
                branch = None

        if branch:  # branch not in list - it is probably closed
            revs = repo._repo.revs('max(branch(%s))', branch)
            if revs:
                cs = repo.get_changeset(revs[0])
                selected = 'branch:%s:%s' % (branch, cs.raw_id)
                branches.append((selected, branch))

        bookmarks = []
        for bookmark, bookmarkrev in repo.bookmarks.iteritems():
            n = 'book:%s:%s' % (bookmark, bookmarkrev)
            bookmarks.append((n, bookmark))
            if rev == bookmarkrev:
                selected = n

        tags = []
        for tag, tagrev in repo.tags.iteritems():
            n = 'tag:%s:%s' % (tag, tagrev)
            tags.append((n, tag))
            if rev == tagrev and tag != 'tip':  # tip is not a real tag - and its branch is better
                selected = n

        # prio 1: rev was selected as existing entry above

        # prio 2: create special entry for rev; rev _must_ be used
        specials = []
        if rev and selected is None:
            selected = 'rev:%s:%s' % (rev, rev)
            specials = [(selected, '%s: %s' % (_("Changeset"), rev[:12]))]

        # prio 3: most recent peer branch
        if peers and not selected:
            selected = peers[0][0][0]

        # prio 4: tip revision
        if not selected:
            if h.is_hg(repo):
                selected = 'tag:tip:%s' % repo.tags['tip']
            else:
                if 'master' in repo.branches:
                    selected = 'branch:master:%s' % repo.branches['master']
                else:
                    k, v = repo.branches.items()[0]
                    selected = 'branch:%s:%s' % (k, v)

        groups = [(specials, _("Special")),
                  (peers, _("Peer branches")),
                  (bookmarks, _("Bookmarks")),
                  (branches, _("Branches")),
                  (tags, _("Tags")),
                  ]
        return [g for g in groups if g[0]], selected

    def _get_is_allowed_change_status(self, pull_request):
        owner = self.authuser.user_id == pull_request.user_id
        reviewer = self.authuser.user_id in [x.user_id for x in
                                                   pull_request.reviewers]
        return self.authuser.admin or owner or reviewer

    def _load_compare_data(self, pull_request, enable_comments=True):
        """
        Load context data needed for generating compare diff

        :param pull_request:
        """
        org_repo = pull_request.org_repo
        (org_ref_type,
         org_ref_name,
         org_ref_rev) = pull_request.org_ref.split(':')

        other_repo = org_repo
        (other_ref_type,
         other_ref_name,
         other_ref_rev) = pull_request.other_ref.split(':')

        # despite opening revisions for bookmarks/branches/tags, we always
        # convert this to rev to prevent changes after bookmark or branch change
        org_ref = ('rev', org_ref_rev)
        other_ref = ('rev', other_ref_rev)

        c.org_repo = org_repo
        c.other_repo = other_repo

        c.fulldiff = fulldiff = request.GET.get('fulldiff')

        c.cs_ranges = [org_repo.get_changeset(x) for x in pull_request.revisions]

        c.statuses = org_repo.statuses([x.raw_id for x in c.cs_ranges])

        c.org_ref = org_ref[1]
        c.org_ref_type = org_ref[0]
        c.other_ref = other_ref[1]
        c.other_ref_type = other_ref[0]

        diff_limit = self.cut_off_limit if not fulldiff else None

        # we swap org/other ref since we run a simple diff on one repo
        log.debug('running diff between %s and %s in %s'
                  % (other_ref, org_ref, org_repo.scm_instance.path))
        txtdiff = org_repo.scm_instance.get_diff(rev1=safe_str(other_ref[1]), rev2=safe_str(org_ref[1]))

        diff_processor = diffs.DiffProcessor(txtdiff or '', format='gitdiff',
                                             diff_limit=diff_limit)
        _parsed = diff_processor.prepare()

        c.limited_diff = False
        if isinstance(_parsed, LimitedDiffContainer):
            c.limited_diff = True

        c.files = []
        c.changes = {}
        c.lines_added = 0
        c.lines_deleted = 0

        for f in _parsed:
            st = f['stats']
            c.lines_added += st['added']
            c.lines_deleted += st['deleted']
            fid = h.FID('', f['filename'])
            c.files.append([fid, f['operation'], f['filename'], f['stats']])
            htmldiff = diff_processor.as_html(enable_comments=enable_comments,
                                              parsed_lines=[f])
            c.changes[fid] = [f['operation'], f['filename'], htmldiff]

    @LoginRequired()
    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                   'repository.admin')
    def show_all(self, repo_name):
        c.from_ = request.GET.get('from_') or ''
        c.closed = request.GET.get('closed') or ''
        c.pull_requests = PullRequestModel().get_all(repo_name, from_=c.from_, closed=c.closed)
        c.repo_name = repo_name
        p = safe_int(request.GET.get('page', 1), 1)

        c.pullrequests_pager = Page(c.pull_requests, page=p, items_per_page=10)

        c.pullrequest_data = render('/pullrequests/pullrequest_data.html')

        if request.environ.get('HTTP_X_PARTIAL_XHR'):
            return c.pullrequest_data

        return render('/pullrequests/pullrequest_show_all.html')

    @LoginRequired()
    @NotAnonymous()
    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                   'repository.admin')
    def index(self):
        org_repo = c.db_repo

        try:
            org_repo.scm_instance.get_changeset()
        except EmptyRepositoryError, e:
            h.flash(h.literal(_('There are no changesets yet')),
                    category='warning')
            redirect(url('summary_home', repo_name=org_repo.repo_name))

        org_rev = request.GET.get('rev_end')
        # rev_start is not directly useful - its parent could however be used
        # as default for other and thus give a simple compare view
        #other_rev = request.POST.get('rev_start')
        branch = request.GET.get('branch')

        c.org_repos = []
        c.org_repos.append((org_repo.repo_name, org_repo.repo_name))
        c.default_org_repo = org_repo.repo_name
        c.org_refs, c.default_org_ref = self._get_repo_refs(org_repo.scm_instance, rev=org_rev, branch=branch)

        c.other_repos = []
        other_repos_info = {}

        def add_other_repo(repo, branch_rev=None):
            if repo.repo_name in other_repos_info: # shouldn't happen
                return
            c.other_repos.append((repo.repo_name, repo.repo_name))
            other_refs, selected_other_ref = self._get_repo_refs(repo.scm_instance, branch_rev=branch_rev)
            other_repos_info[repo.repo_name] = {
                'user': dict(user_id=repo.user.user_id,
                             username=repo.user.username,
                             firstname=repo.user.firstname,
                             lastname=repo.user.lastname,
                             gravatar_link=h.gravatar_url(repo.user.email, 14)),
                'description': repo.description.split('\n', 1)[0],
                'revs': h.select('other_ref', selected_other_ref, other_refs, class_='refs')
            }

        # add org repo to other so we can open pull request against peer branches on itself
        add_other_repo(org_repo, branch_rev=org_rev)
        c.default_other_repo = org_repo.repo_name

        # gather forks and add to this list ... even though it is rare to
        # request forks to pull from their parent
        for fork in org_repo.forks:
            add_other_repo(fork)

        # add parents of this fork also, but only if it's not empty
        if org_repo.parent and org_repo.parent.scm_instance.revisions:
            add_other_repo(org_repo.parent)
            c.default_other_repo = org_repo.parent.repo_name

        c.default_other_repo_info = other_repos_info[c.default_other_repo]
        c.other_repos_info = json.dumps(other_repos_info)

        return render('/pullrequests/pullrequest.html')

    @LoginRequired()
    @NotAnonymous()
    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                   'repository.admin')
    def create(self, repo_name):
        repo = RepoModel()._get_repo(repo_name)
        try:
            _form = PullRequestForm(repo.repo_id)().to_python(request.POST)
        except formencode.Invalid, errors:
            log.error(traceback.format_exc())
            if errors.error_dict.get('revisions'):
                msg = 'Revisions: %s' % errors.error_dict['revisions']
            elif errors.error_dict.get('pullrequest_title'):
                msg = _('Pull request requires a title with min. 3 chars')
            else:
                msg = _('Error creating pull request: %s') % errors.msg

            h.flash(msg, 'error')
            return redirect(url('pullrequest_home', repo_name=repo_name)) ## would rather just go back to form ...

        org_repo = _form['org_repo']
        org_ref = _form['org_ref'] # will end with merge_rev but have symbolic name
        other_repo = _form['other_repo']
        other_ref = 'rev:ancestor:%s' % _form['ancestor_rev'] # could be calculated from other_ref ...
        revisions = [x for x in reversed(_form['revisions'])]
        reviewers = _form['review_members']

        title = _form['pullrequest_title']
        if not title:
            title = '%s#%s to %s' % (org_repo, org_ref.split(':', 2)[1], other_repo)
        description = _form['pullrequest_desc']
        try:
            pull_request = PullRequestModel().create(
                self.authuser.user_id, org_repo, org_ref, other_repo,
                other_ref, revisions, reviewers, title, description
            )
            Session().commit()
            h.flash(_('Successfully opened new pull request'),
                    category='success')
        except Exception:
            h.flash(_('Error occurred during sending pull request'),
                    category='error')
            log.error(traceback.format_exc())
            return redirect(url('pullrequest_home', repo_name=repo_name))

        return redirect(url('pullrequest_show', repo_name=other_repo,
                            pull_request_id=pull_request.pull_request_id))

    @LoginRequired()
    @NotAnonymous()
    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                   'repository.admin')
    @jsonify
    def update(self, repo_name, pull_request_id):
        pull_request = PullRequest.get_or_404(pull_request_id)
        if pull_request.is_closed():
            raise HTTPForbidden()
        #only owner or admin can update it
        owner = pull_request.author.user_id == c.authuser.user_id
        repo_admin = h.HasRepoPermissionAny('repository.admin')(c.repo_name)
        if h.HasPermissionAny('hg.admin') or repo_admin or owner:
            reviewers_ids = map(int, filter(lambda v: v not in [None, ''],
                request.POST.get('reviewers_ids', '').split(',')))

            PullRequestModel().update_reviewers(pull_request_id, reviewers_ids)
            Session().commit()
            return True
        raise HTTPForbidden()

    @LoginRequired()
    @NotAnonymous()
    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                   'repository.admin')
    @jsonify
    def delete(self, repo_name, pull_request_id):
        pull_request = PullRequest.get_or_404(pull_request_id)
        #only owner can delete it !
        if pull_request.author.user_id == c.authuser.user_id:
            PullRequestModel().delete(pull_request)
            Session().commit()
            h.flash(_('Successfully deleted pull request'),
                    category='success')
            return redirect(url('my_account_pullrequests'))
        raise HTTPForbidden()

    @LoginRequired()
    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                   'repository.admin')
    def show(self, repo_name, pull_request_id):
        repo_model = RepoModel()
        c.users_array = repo_model.get_users_js()
        c.user_groups_array = repo_model.get_user_groups_js()
        c.pull_request = PullRequest.get_or_404(pull_request_id)
        c.allowed_to_change_status = self._get_is_allowed_change_status(c.pull_request)
        cc_model = ChangesetCommentsModel()
        cs_model = ChangesetStatusModel()
        _cs_statuses = cs_model.get_statuses(c.pull_request.org_repo,
                                            pull_request=c.pull_request,
                                            with_revisions=True)

        cs_statuses = defaultdict(list)
        for st in _cs_statuses:
            cs_statuses[st.author.username] += [st]

        c.pull_request_reviewers = []
        c.pull_request_pending_reviewers = []
        for o in c.pull_request.reviewers:
            st = cs_statuses.get(o.user.username, None)
            if st:
                sorter = lambda k: k.version
                st = [(x, list(y)[0])
                      for x, y in (groupby(sorted(st, key=sorter), sorter))]
            else:
                c.pull_request_pending_reviewers.append(o.user)
            c.pull_request_reviewers.append([o.user, st])

        # pull_requests repo_name we opened it against
        # ie. other_repo must match
        if repo_name != c.pull_request.other_repo.repo_name:
            raise HTTPNotFound

        # load compare data into template context
        enable_comments = not c.pull_request.is_closed()
        self._load_compare_data(c.pull_request, enable_comments=enable_comments)

        # inline comments
        c.inline_cnt = 0
        c.inline_comments = cc_model.get_inline_comments(
                                c.db_repo.repo_id,
                                pull_request=pull_request_id)
        # count inline comments
        for __, lines in c.inline_comments:
            for comments in lines.values():
                c.inline_cnt += len(comments)
        # comments
        c.comments = cc_model.get_comments(c.db_repo.repo_id,
                                           pull_request=pull_request_id)

        # (badly named) pull-request status calculation based on reviewer votes
        c.current_changeset_status = cs_model.calculate_status(
                                        c.pull_request_reviewers,
                                         )
        c.changeset_statuses = ChangesetStatus.STATUSES

        c.as_form = False
        c.ancestor = None # there is one - but right here we don't know which
        return render('/pullrequests/pullrequest_show.html')

    @LoginRequired()
    @NotAnonymous()
    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                   'repository.admin')
    @jsonify
    def comment(self, repo_name, pull_request_id):
        pull_request = PullRequest.get_or_404(pull_request_id)
        if pull_request.is_closed():
            raise HTTPForbidden()

        status = request.POST.get('changeset_status')
        change_status = request.POST.get('change_changeset_status')
        text = request.POST.get('text')
        close_pr = request.POST.get('save_close')

        allowed_to_change_status = self._get_is_allowed_change_status(pull_request)
        if status and change_status and allowed_to_change_status:
            _def = (_('Status change -> %s')
                            % ChangesetStatus.get_status_lbl(status))
            if close_pr:
                _def = _('Closing with') + ' ' + _def
            text = text or _def
        comm = ChangesetCommentsModel().create(
            text=text,
            repo=c.db_repo.repo_id,
            user=c.authuser.user_id,
            pull_request=pull_request_id,
            f_path=request.POST.get('f_path'),
            line_no=request.POST.get('line'),
            status_change=(ChangesetStatus.get_status_lbl(status)
                           if status and change_status
                           and allowed_to_change_status else None),
            closing_pr=close_pr
        )

        action_logger(self.authuser,
                      'user_commented_pull_request:%s' % pull_request_id,
                      c.db_repo, self.ip_addr, self.sa)

        if allowed_to_change_status:
            # get status if set !
            if status and change_status:
                ChangesetStatusModel().set_status(
                    c.db_repo.repo_id,
                    status,
                    c.authuser.user_id,
                    comm,
                    pull_request=pull_request_id
                )

            if close_pr:
                if status in ['rejected', 'approved']:
                    PullRequestModel().close_pull_request(pull_request_id)
                    action_logger(self.authuser,
                              'user_closed_pull_request:%s' % pull_request_id,
                              c.db_repo, self.ip_addr, self.sa)
                else:
                    h.flash(_('Closing pull request on other statuses than '
                              'rejected or approved forbidden'),
                            category='warning')

        Session().commit()

        if not request.environ.get('HTTP_X_PARTIAL_XHR'):
            return redirect(h.url('pullrequest_show', repo_name=repo_name,
                                  pull_request_id=pull_request_id))

        data = {
           'target_id': h.safeid(h.safe_unicode(request.POST.get('f_path'))),
        }
        if comm:
            c.co = comm
            data.update(comm.get_dict())
            data.update({'rendered_text':
                         render('changeset/changeset_comment_block.html')})

        return data

    @LoginRequired()
    @NotAnonymous()
    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                   'repository.admin')
    @jsonify
    def delete_comment(self, repo_name, comment_id):
        co = ChangesetComment.get(comment_id)
        if co.pull_request.is_closed():
            #don't allow deleting comments on closed pull request
            raise HTTPForbidden()

        owner = co.author.user_id == c.authuser.user_id
        repo_admin = h.HasRepoPermissionAny('repository.admin')(c.repo_name)
        if h.HasPermissionAny('hg.admin') or repo_admin or owner:
            ChangesetCommentsModel().delete(comment=co)
            Session().commit()
            return True
        else:
            raise HTTPForbidden()