# -*- coding: utf-8 -*-
##############################################################################
#
#    Copyright (C) 2015 Innoviu srl (<http://www.innoviu.com>).
#    Copyright (C) 2015 Agile Business Group http://www.agilebg.com
#    @authors
#       Roberto Onnis <roberto.onnis@innoviu.com>
#       Alessio Gerace <alessio.gerace@agilebg.com>
#       Lorenzo Battistini <lorenzo.battistini@agilebg.com>
#
#    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/>.
##############################################################################
from openerp.osv import fields, orm
import logging
import imaplib
from datetime import datetime
import time


_logger = logging.getLogger(__name__)


class FetchmailServer(orm.Model):

    _inherit = "fetchmail.server"

    _columns = {
        'last_internal_date': fields.datetime(
            'Last Download Date',
            help="Remote emails with a date greater than this will be "
                 "downloaded. Only available with IMAP"),
    }

    def _fetch_from_date_imap(self, cr, uid,
                              server, imap_server,
                              mail_thread, action_pool,
                              count, failed,
                              context=None):
        messages = []
        date_uids = {}
        last_date = False
        last_internal_date = datetime.strptime(
            server.last_internal_date, "%Y-%m-%d %H:%M:%S")
        search_status, uids = imap_server.search(
            None,
            'SINCE', '%s' % last_internal_date.strftime('%d-%b-%Y')
            )
        new_uids = uids[0].split()
        for new_uid in new_uids:
            fetch_status, date = imap_server.fetch(
                int(new_uid),
                'INTERNALDATE'
                )
            internaldate = imaplib.Internaldate2tuple(date[0])
            internaldate_msg = datetime.fromtimestamp(
                time.mktime(internaldate)
                )
            if internaldate_msg > last_internal_date:
                messages.append(new_uid)
                date_uids[new_uid] = internaldate_msg
        for num in messages:
            # SEARCH command *always* returns at least the most
            # recent message, even if it has already been synced
            res_id = None
            result, data = imap_server.fetch(num, '(RFC822)')
            if data and data[0]:
                try:
                    res_id = mail_thread.message_process(
                        cr, uid,
                        server.object_id.model,
                        data[0][1],
                        save_original=server.original,
                        strip_attachments=(not server.attach),
                        context=context)
                except Exception:
                    _logger.exception(
                        'Failed to process mail \
                        from %s server %s.',
                        server.type,
                        server.name)
                    failed += 1
                if res_id and server.action_id:
                    action_pool.run(
                        cr, uid, [server.action_id.id],
                        {
                            'active_id': res_id,
                            'active_ids': [res_id],
                            'active_model': context.get(
                                "thread_model",
                                server.object_id.model)
                        }, context=context)
                imap_server.store(num, '+FLAGS', '\\Seen')
                cr.commit()
                count += 1
                last_date = not failed and date_uids[num] or False
        return count, failed, last_date

    def fetch_mail(self, cr, uid, ids, context=None):
        if context is None:
            context = {}
        context['fetchmail_cron_running'] = True
        mail_thread = self.pool.get('mail.thread')
        action_pool = self.pool.get('ir.actions.server')
        for server in self.browse(cr, uid, ids, context=context):
            if server.type == 'imap' and server.last_internal_date:
                _logger.info(
                    'start checking for new emails by date on %s server %s',
                    server.type, server.name)
                context.update({'fetchmail_server_id': server.id,
                                'server_type': server.type})
                count, failed = 0, 0
                last_date = False
                imap_server = False
                try:
                    imap_server = server.connect()
                    imap_server.select()
                    count, failed, last_date = self._fetch_from_date_imap(
                        cr, uid, server, imap_server, mail_thread,
                        action_pool, count, failed, context=context
                    )
                except Exception:
                    _logger.exception(
                        "General failure when trying to fetch mail \
                        from %s server %s.",
                        server.type,
                        server.name
                        )
                finally:
                    if imap_server:
                        imap_server.close()
                        imap_server.logout()
                if last_date:
                    _logger.info(
                        "Fetched %d email(s) on %s server %s; \
                        %d succeeded, %d failed.", count,
                        server.type, server.name,
                        (count - failed), failed)
                    vals = {'last_internal_date': last_date}
                    server.write(vals)
        return super(FetchmailServer, self).fetch_mail(
            cr, uid, ids, context=context)