text: # -*- coding: utf-8 -*-
  ##############################################################################
  #
  #    OpenERP, Open Source Management Solution
  #    Copyright (C) 2004-2010 Tiny SPRL (<http://tiny.be>).
  #
  #    This program is free software: you can redistribute it and/or modify
  #    it under the terms of the GNU Affero 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 Affero General Public License for more details.
  #
  #    You should have received a copy of the GNU Affero General Public License
  #    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  #
  ##############################################################################
  
  import time
  
  from openerp.osv import fields, osv
  from openerp.tools.translate import _
  
  class hr_action_reason(osv.osv):
      _name = "hr.action.reason"
      _description = "Action Reason"
      _columns = {
          'name': fields.char('Reason', size=64, required=True, help='Specifies the reason for Signing In/Signing Out.'),
          'action_type': fields.selection([('sign_in', 'Sign in'), ('sign_out', 'Sign out')], "Action Type"),
      }
      _defaults = {
          'action_type': 'sign_in',
      }
  
  hr_action_reason()
  
  def _employee_get(obj, cr, uid, context=None):
      ids = obj.pool.get('hr.employee').search(cr, uid, [('user_id', '=', uid)], context=context)
      return ids and ids[0] or False
  
  class hr_attendance(osv.osv):
      _name = "hr.attendance"
      _description = "Attendance"
  
      def _day_compute(self, cr, uid, ids, fieldnames, args, context=None):
          res = dict.fromkeys(ids, '')
          for obj in self.browse(cr, uid, ids, context=context):
              res[obj.id] = time.strftime('%Y-%m-%d', time.strptime(obj.name, '%Y-%m-%d %H:%M:%S'))
          return res
  
      _columns = {
          'name': fields.datetime('Date', required=True, select=1),
          'action': fields.selection([('sign_in', 'Sign In'), ('sign_out', 'Sign Out'), ('action','Action')], 'Action', required=True),
          'action_desc': fields.many2one("hr.action.reason", "Action Reason", domain="[('action_type', '=', action)]", help='Specifies the reason for Signing In/Signing Out in case of extra hours.'),
          'employee_id': fields.many2one('hr.employee', "Employee", required=True, select=True),
          'day': fields.function(_day_compute, type='char', string='Day', store=True, select=1, size=32),
      }
      _defaults = {
          'name': lambda *a: time.strftime('%Y-%m-%d %H:%M:%S'), #please don't remove the lambda, if you remove it then the current time will not change
          'employee_id': _employee_get,
      }
  
      def _altern_si_so(self, cr, uid, ids, context=None):
          """ Alternance sign_in/sign_out check.
              Previous (if exists) must be of opposite action.
              Next (if exists) must be of opposite action.
          """
          for att in self.browse(cr, uid, ids, context=context):
              # search and browse for first previous and first next records
              prev_att_ids = self.search(cr, uid, [('employee_id', '=', att.employee_id.id), ('name', '<', att.name), ('action', 'in', ('sign_in', 'sign_out'))], limit=1, order='name DESC')
              next_add_ids = self.search(cr, uid, [('employee_id', '=', att.employee_id.id), ('name', '>', att.name), ('action', 'in', ('sign_in', 'sign_out'))], limit=1, order='name ASC')
              prev_atts = self.browse(cr, uid, prev_att_ids, context=context)
              next_atts = self.browse(cr, uid, next_add_ids, context=context)
              # check for alternance, return False if at least one condition is not satisfied
              if prev_atts and prev_atts[0].action == att.action: # previous exists and is same action
                  return False
              if next_atts and next_atts[0].action == att.action: # next exists and is same action
                  return False
              if (not prev_atts) and (not next_atts) and att.action != 'sign_in': # first attendance must be sign_in
                  return False
          return True
  
      _constraints = [(_altern_si_so, 'Error ! Sign in (resp. Sign out) must follow Sign out (resp. Sign in)', ['action'])]
      _order = 'name desc'
  
  hr_attendance()
  
  class hr_employee(osv.osv):
      _inherit = "hr.employee"
      _description = "Employee"
  
      def _state(self, cr, uid, ids, name, args, context=None):
          result = {}
          if not ids:
              return result
          for id in ids:
              result[id] = 'absent'
          cr.execute('SELECT hr_attendance.action, hr_attendance.employee_id \
                  FROM ( \
                      SELECT MAX(name) AS name, employee_id \
                      FROM hr_attendance \
                      WHERE action in (\'sign_in\', \'sign_out\') \
                      GROUP BY employee_id \
                  ) AS foo \
                  LEFT JOIN hr_attendance \
                      ON (hr_attendance.employee_id = foo.employee_id \
                          AND hr_attendance.name = foo.name) \
                  WHERE hr_attendance.employee_id IN %s',(tuple(ids),))
          for res in cr.fetchall():
              result[res[1]] = res[0] == 'sign_in' and 'present' or 'absent'
          return result
      
      def _last_sign(self, cr, uid, ids, name, args, context=None):
          result = {}
          if not ids:
              return result
          for id in ids:
              result[id] = False
              cr.execute("""select max(name) as name
                          from hr_attendance
                          where action in ('sign_in', 'sign_out') and employee_id = %s""",(id,))
              for res in cr.fetchall():
                  result[id] = res[0]
          return result
  
      def _attendance_access(self, cr, uid, ids, name, args, context=None):
          # this function field use to hide attendance button to singin/singout from menu
          group = self.pool.get('ir.model.data').get_object(cr, uid, 'base', 'group_hr_attendance')
          visible = False
          if uid in [user.id for user in group.users]:
              visible = True
          return dict([(x, visible) for x in ids])
  
      _columns = {
         'state': fields.function(_state, type='selection', selection=[('absent', 'Absent'), ('present', 'Present')], string='Attendance'),
         'last_sign': fields.function(_last_sign, type='datetime', string='Last Sign'),
         'attendance_access': fields.function(_attendance_access, string='Attendance Access', type='boolean'),
      }
  
      def _action_check(self, cr, uid, emp_id, dt=False, context=None):
          cr.execute('SELECT MAX(name) FROM hr_attendance WHERE employee_id=%s', (emp_id,))
          res = cr.fetchone()
          return not (res and (res[0]>=(dt or time.strftime('%Y-%m-%d %H:%M:%S'))))
  
      def attendance_action_change(self, cr, uid, ids, context=None):
          if context is None:
              context = {}
          action_date = context.get('action_date', False)
          action = context.get('action', False)
          hr_attendance = self.pool.get('hr.attendance')
          warning_sign = {'sign_in': _('Sign In'), 'sign_out': _('Sign Out')}
          for employee in self.browse(cr, uid, ids, context=context):
              if not action:
                  if employee.state == 'present': action = 'sign_out'
                  if employee.state == 'absent': action = 'sign_in'
  
              if not self._action_check(cr, uid, employee.id, action_date, context):
                  raise osv.except_osv(_('Warning'), _('You tried to %s with a date anterior to another event !\nTry to contact the HR Manager to correct attendances.')%(warning_sign[action],))
  
              vals = {'action': action, 'employee_id': employee.id}
              if action_date:
                  vals['name'] = action_date
              hr_attendance.create(cr, uid, vals, context=context)
          return True
  
  hr_employee()
  
  # vim:expandtab:smartindent:tabstop=4:softtabstop=4:shiftwidth=4:
  