# -*- coding: utf-8 -*-
"""
    rhodecode.controllers.changelog
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    changelog controller for rhodecode
    
    :created_on: Apr 21, 2010
    :author: marcink
    :copyright: (C) 2009-2011 Marcin Kuzminski <marcin@python-works.com>    
    :license: GPLv3, see COPYING for more details.
"""
# 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; version 2
# of the License or (at your opinion) any later version of the license.
# 
# 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, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
# MA  02110-1301, USA.

import logging

try:
    import json
except ImportError:
    #python 2.5 compatibility
    import simplejson as json

from mercurial.graphmod import colored, CHANGESET, revisions as graph_rev
from pylons import request, session, tmpl_context as c

from rhodecode.lib.auth import LoginRequired, HasRepoPermissionAnyDecorator
from rhodecode.lib.base import BaseRepoController, render
from rhodecode.lib.helpers import RepoPage

log = logging.getLogger(__name__)

class ChangelogController(BaseRepoController):

    @LoginRequired()
    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                   'repository.admin')
    def __before__(self):
        super(ChangelogController, self).__before__()

    def index(self):
        limit = 100
        default = 20
        if request.params.get('size'):
            try:
                int_size = int(request.params.get('size'))
            except ValueError:
                int_size = default
            int_size = int_size if int_size <= limit else limit
            c.size = int_size
            session['changelog_size'] = c.size
            session.save()
        else:
            c.size = int(session.get('changelog_size', default))

        p = int(request.params.get('page', 1))
        branch_name = request.params.get('branch', None)
        c.total_cs = len(c.rhodecode_repo)
        c.pagination = RepoPage(c.rhodecode_repo, page=p, item_count=c.total_cs,
                            items_per_page=c.size, branch_name=branch_name)

        self._graph(c.rhodecode_repo, c.size, p)

        return render('changelog/changelog.html')


    def _graph(self, repo, size, p):
        """
        Generates a DAG graph for mercurial
        
        :param repo: repo instance
        :param size: number of commits to show
        :param p: page number
        """
        if not repo.revisions or repo.alias == 'git':
            c.jsdata = json.dumps([])
            return

        revcount = min(repo.size, size)
        offset = 1 if p == 1 else  ((p - 1) * revcount + 1)
        rev_start = repo.revisions.index(repo.revisions[(-1 * offset)])
        rev_end = max(0, rev_start - revcount)

        dag = graph_rev(repo._repo, rev_start, rev_end)
        c.dag = tree = list(colored(dag))
        data = []
        for (id, type, ctx, vtx, edges) in tree:
            if type != CHANGESET:
                continue
            data.append(('', vtx, edges))

        c.jsdata = json.dumps(data)