# -*- 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 Kallithea for initializing pull requests

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: May 7, 2012
:author: marcink
:copyright: (c) 2013 RhodeCode GmbH, and others.
: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,\
    PullRequestReviewers
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, PullRequestPostForm
from kallithea.lib.utils2 import safe_int
from kallithea.controllers.changeset import anchor_url, _ignorews_url,\
    _context_url, get_line_ctx, get_ignore_ws
from kallithea.controllers.compare import CompareController
from kallithea.lib.graphmod import graph_data

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)
            # a revset not restricting to merge() would be better
            # (especially because it would get the branch point)
            # ... but is currently too expensive
            # including branches of children could be nice too
            peerbranches = set()
            for i in repo._repo.revs(
                "sort(parents(branch(id(%s)) and merge()) - branch(id(%s)), -rev)",
                branch_rev, branch_rev):
                abranch = repo.get_changeset(i).branch
                if abranch not in peerbranches:
                    n = 'branch:%s:%s' % (abranch, repo.get_changeset(abranch).raw_id)
                    peers.append((n, abranch))
                    peerbranches.add(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:
                if not rev:
                    selected = n
                branch = None
        if branch:  # branch not in list - it is probably closed
            branchrev = repo.closed_branches.get(branch)
            if branchrev:
                n = 'branch:%s:%s' % (branch, branchrev)
                branches.append((n, _('%s (closed)') % branch))
                selected = n
                branch = None
            if branch:
                log.error('branch %r not found in %s', branch, repo)

        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):
                if 'tip' in repo.tags:
                    selected = 'tag:tip:%s' % repo.tags['tip']
                else:
                    selected = 'tag:null:0'
                    tags.append((selected, 'null'))
            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:
        """
        c.org_repo = pull_request.org_repo
        (c.org_ref_type,
         c.org_ref_name,
         c.org_rev) = pull_request.org_ref.split(':')

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

        org_scm_instance = c.org_repo.scm_instance # property with expensive cache invalidation check!!!
        c.cs_ranges = [org_scm_instance.get_changeset(x) for x in pull_request.revisions]
        c.cs_ranges_org = None # not stored and not important and moving target - could be calculated ...
        revs = [ctx.revision for ctx in reversed(c.cs_ranges)]
        c.jsdata = json.dumps(graph_data(org_scm_instance, revs))

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

        ignore_whitespace = request.GET.get('ignorews') == '1'
        line_context = request.GET.get('context', 3)
        c.ignorews_url = _ignorews_url
        c.context_url = _context_url
        c.fulldiff = request.GET.get('fulldiff')
        diff_limit = self.cut_off_limit if not c.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'
                  % (c.other_rev, c.org_rev, org_scm_instance.path))
        txtdiff = org_scm_instance.get_diff(rev1=safe_str(c.other_rev), rev2=safe_str(c.org_rev),
                                      ignore_whitespace=ignore_whitespace,
                                      context=line_context)

        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()
    def show_my(self): # my_account_my_pullrequests
        c.show_closed = request.GET.get('pr_show_closed')
        return render('/pullrequests/pullrequest_show_my.html')

    @NotAnonymous()
    def show_my_data(self):
        c.show_closed = request.GET.get('pr_show_closed')

        def _filter(pr):
            s = sorted(pr, key=lambda o: o.created_on, reverse=True)
            if not c.show_closed:
                s = filter(lambda p: p.status != PullRequest.STATUS_CLOSED, s)
            return s

        c.my_pull_requests = _filter(PullRequest.query()\
                                .filter(PullRequest.user_id ==
                                        self.authuser.user_id)\
                                .all())

        c.participate_in_pull_requests = _filter(PullRequest.query()\
                                .join(PullRequestReviewers)\
                                .filter(PullRequestReviewers.user_id ==
                                        self.authuser.user_id)\
                                                 )

        return render('/pullrequests/pullrequest_show_my_data.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())
            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 ...

        # heads up: org and other might seem backward here ...
        org_repo_name = _form['org_repo']
        org_ref = _form['org_ref'] # will have merge_rev as rev but symbolic name
        org_repo = RepoModel()._get_repo(org_repo_name)
        (org_ref_type,
         org_ref_name,
         org_rev) = org_ref.split(':')

        other_repo_name = _form['other_repo']
        other_ref = _form['other_ref'] # will have symbolic name and head revision
        other_repo = RepoModel()._get_repo(other_repo_name)
        (other_ref_type,
         other_ref_name,
         other_rev) = other_ref.split(':')

        cs_ranges, _cs_ranges_not, ancestor_rev = \
            CompareController._get_changesets(org_repo.scm_instance.alias,
                                              other_repo.scm_instance, other_rev, # org and other "swapped"
                                              org_repo.scm_instance, org_rev,
                                              )
        revisions = [cs.raw_id for cs in cs_ranges]

        # hack: ancestor_rev is not an other_ref 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)

        reviewers = _form['review_members']

        title = _form['pullrequest_title']
        if not title:
            title = '%s#%s to %s#%s' % (org_repo_name, h.short_ref(org_ref_type, org_ref_name),
                                        other_repo_name, h.short_ref(other_ref_type, other_ref_name))
        description = _form['pullrequest_desc'].strip() or _('No description')
        try:
            pull_request = PullRequestModel().create(
                self.authuser.user_id, org_repo_name, org_ref, other_repo_name,
                other_ref, revisions, reviewers, title, description
            )
            Session().commit()
            h.flash(_('Successfully opened new pull request'),
                    category='success')
        except Exception:
            h.flash(_('Error occurred while creating 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_name,
                            pull_request_id=pull_request.pull_request_id))

    @LoginRequired()
    @NotAnonymous()
    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                   'repository.admin')
    def post(self, repo_name, pull_request_id):
        repo = RepoModel()._get_repo(repo_name)
        pull_request = PullRequest.get_or_404(pull_request_id)

        _form = PullRequestPostForm()().to_python(request.POST)

        pull_request.title = _form['pullrequest_title']
        pull_request.description = _form['pullrequest_desc'].strip() or _('No description')

        Session().commit()
        h.flash(_('Pull request updated'), category='success')

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

        # 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.pull_request_reviewers,
         c.pull_request_pending_reviewers,
         c.current_voting_result,
         ) = cs_model.calculate_pull_request_result(c.pull_request)
        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')
        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 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 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:
                ChangesetStatusModel().set_status(
                    c.db_repo.repo_id,
                    status,
                    c.authuser.user_id,
                    comm,
                    pull_request=pull_request_id
                )

            if close_pr:
                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)

        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()