import rhodecode.lib.helpers as h

from rhodecode.lib.auth import LoginRequired, HasRepoPermissionAnyDecorator

from rhodecode.lib.base import BaseRepoController, render

from rhodecode.lib.helpers import RepoPage

from rhodecode.lib.compat import json

from rhodecode.lib.vcs.exceptions import RepositoryError, ChangesetDoesNotExistError

from rhodecode.model.db import Repository

log = logging.getLogger(__name__)

class ChangelogController(BaseRepoController):

    @LoginRequired()

    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',

                                   'repository.admin')

    def __before__(self):

        super(ChangelogController, self).__before__()

        c.affected_files_cut_off = 60

    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)

        try:

            if branch_name:

                collection = [z for z in

                              c.rhodecode_repo.get_changesets(start=0,

                                                    branch_name=branch_name)]

                c.total_cs = len(collection)

            else:

                collection = c.rhodecode_repo

                c.total_cs = len(c.rhodecode_repo)

            c.pagination = RepoPage(collection, page=p, item_count=c.total_cs,

                                    items_per_page=c.size, branch=branch_name)

            collection = list(c.pagination)

            page_revisions = [x.raw_id for x in collection]

            c.comments = c.rhodecode_db_repo.comments(page_revisions)

        except (RepositoryError, ChangesetDoesNotExistError, Exception), e:

            log.error(traceback.format_exc())

            h.flash(str(e), category='warning')

            return redirect(url('home'))

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

        c.branch_name = branch_name

        c.branch_filters = [('', _('All Branches'))] + \

            [(k, k) for k in c.rhodecode_repo.branches.keys()]

        return render('changelog/changelog.html')

    def changelog_details(self, cs):

        if request.environ.get('HTTP_X_PARTIAL_XHR'):

            c.cs = c.rhodecode_repo.get_changeset(cs)

            return render('changelog/changelog_details.html')

    def _graph(self, repo, collection, repo_size, 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 collection:

            c.jsdata = json.dumps([])

            return

        data = []

        revs = [x.revision for x in collection]

        if repo.alias == 'git':

            for _ in revs:

                vtx = [0, 1]

                edges = [[0, 0, 1]]

                data.append(['', vtx, edges])

        elif repo.alias == 'hg':

            dag = graphmod.dagwalker(repo._repo, revs)

            c.dag = graphmod.colored(dag, repo._repo)

            for (id, type, ctx, vtx, edges) in c.dag:

                if type != graphmod.CHANGESET:

                    continue

                data.append(['', vtx, edges])

        c.jsdata = json.dumps(data)