from datetime import datetime
from openerp.tools import DEFAULT_SERVER_DATE_FORMAT as OE_DFORMAT

from openerp import models, fields, api


class ResPartner(models.Model):
    _inherit = 'res.partner'

    def _search_age(self, operator, value):
        if operator not in ('=', '!=', '<', '<=', '>', '>=', 'in', 'not in'):
            return []
        query = """SELECT id
                   FROM "%s"
                   WHERE extract(year from age(CURRENT_DATE,
                                               birthdate_date)) %s %%s""" % \
                (self._table, operator)
        self.env.cr.execute(query, (value,))
        ids = [t[0] for t in self.env.cr.fetchall()]
        return [('id', 'in', ids)]

    @api.one
    @api.depends('birthdate_date')
    def _compute_age(self):
        if self.birthdate_date:
            dBday = datetime.strptime(str(self.birthdate_date),
                                      OE_DFORMAT).date()
            dToday = datetime.now().date()
            self.age = dToday.year - dBday.year - ((
                dToday.month, dToday.day) < (dBday.month, dBday.day))

    age = fields.Integer(string='Age',
                         compute='_compute_age',
                         search='_search_age')