# -*- coding: utf-8 -*-

import re
from trac.core import *
from tractags.api import TagSystem, ITagProvider
from trac.util.text import to_unicode
from trac.util.compat import set, sorted
from trac.config import *
from trac.resource import Resource

from model import RendezVous

__all__ = ['RendezVousTagProvider',]

class RendezVousTagProvider(Component):
    """A tag provider using rendezvous tag field as sources of tags.
    """
    implements(ITagProvider)

    ignore_closed_rendezvous = BoolOption('tags', 'ignore_closed_rendezvous', True,
        'Do not collect tags from closed rendezvous.')

    # ITagProvider methods
    def get_taggable_realm(self):
        return 'rendezvous'

    def get_tagged_resources(self, req, tags):
        if 'RENDEZVOUS_VIEW' not in req.perm:
            return

        split_into_tags = TagSystem(self.env).split_into_tags
        db = self.env.get_db_cnx()
        cursor = db.cursor()
        args = []
        ignore = ''
        if self.ignore_closed_rendezvous:
            ignore = " WHERE status != 'closed'"
        sql = "SELECT * FROM (SELECT rendezvous_id, tags, COALESCE(tags, '') as fields FROM rendezvous%s)" % ignore
        constraints = []
        if tags:
            constraints.append(
                "(" + ' OR '.join(["fields LIKE %s" for t in tags]) + ")")
            args += ['%' + t + '%' for t in tags]
        else:
            constraints.append("fields != ''")

        if constraints:
            sql += " WHERE " + " AND ".join(constraints)
        sql += " ORDER BY rendezvous_id"
        self.env.log.debug(sql)
        cursor.execute(sql, args)
        for row in cursor:
            id, ttags = row[0], ' '.join([f for f in row[1:-1] if f])
            rendezvous_tags = split_into_tags(ttags)
            tags = set([to_unicode(x) for x in tags])
            if (not tags or rendezvous_tags.intersection(tags)):
                yield Resource('rendezvous', id), rendezvous_tags

    def get_resource_tags(self, req, resource):
        if 'RENDEZVOUS_VIEW' not in req.perm(resource):
            return
        rendezvous = RendezVous.fetch_one(self.env, resource.id)
        tags = self._rendezvous_tags(rendezvous)
        return tags

    def set_resource_tags(self, req, resource, tags):
        #req.perm.require('RENDEZVOUS_MODIFY', resource)
        split_into_tags = TagSystem(self.env).split_into_tags
        rendezvous = RendezVous.fetch_one(self.env, resource.id)
        all = self._rendezvous_tags(rendezvous)
        tags.difference_update(all.difference(rendezvous.tags))
        rendezvous.tags = u' '.join(sorted(map(to_unicode, tags)))
        rendezvous.update()

    def remove_resource_tags(self, req, resource):
        req.perm.require('RENDEZVOUS_MODIFY', resource)
        rendezvous = RendezVous.fetch_one(self.env, resource.id)
        rendezvous.tags = None
        rendezvous.update()

    # Private methods
    def _rendezvous_tags(self, rendezvous):
        return TagSystem(self.env).split_into_tags(rendezvous.tags)