[IMP] event: use overridable getters for ics file

Currently the summary and description in event ics file generation
are set directly, with a condition in case the event is an appointment.

We make these two ics 'fields' use a getter so that it can be
overriden inside appointment instead.

In addition we remove the special formater for 'online events'
as it is only used for appointments, which does not use it anymore
as of this task

task-3232952

closes odoo/odoo#116211

Related: odoo/enterprise#38570
Signed-off-by: Thibault Delavallee (tde) <tde@openerp.com>

addons/calendar/models/calendar_event.py

@@ -1195,13 +1195,10 @@ class Meeting(models.Model):
             event.add('created').value = ics_datetime(fields.Datetime.now())
             event.add('dtstart').value = ics_datetime(meeting.start, meeting.allday)
             event.add('dtend').value = ics_datetime(meeting.stop, meeting.allday)
-            event.add('summary').value = meeting.name
-            if not is_html_empty(meeting.description):
-                if 'appointment_type_id' in meeting._fields and self.appointment_type_id:
-                    # convert_online_event_desc_to_text method for correct data formatting in external calendars
-                    event.add('description').value = self.convert_online_event_desc_to_text(meeting.description)
-                else:
-                    event.add('description').value = html2plaintext(meeting.description)
+            event.add('summary').value = meeting._get_customer_summary()
+            description = meeting._get_customer_description()
+            if description:
+                event.add('description').value = description
             if meeting.location:
                 event.add('location').value = meeting.location
             if meeting.rrule:
@@ -1237,22 +1234,13 @@ class Meeting(models.Model):
 
         return result
 
-    def convert_online_event_desc_to_text(self, description):
-        """
-        We can sync the calendar events with google calendar, iCal and Outlook, and we
-        also pass the event description along with other data. This description needs
-        to be in plaintext to be displayed properly in above platforms. Because online
-        events have fixed format for the description, this method removes some specific
-        html tags, and converts it into readable plaintext (to be used in external
-        calendars). Note that for regular (offline) events, we simply use the standard
-        `html2plaintext` method instead.
-        """
-        desc_str = str(description)
-        tags_to_replace = ["<ul>", "</ul>", "<li>"]
-        for tag in tags_to_replace:
-            desc_str = desc_str.replace(tag, "")
-        desc_str = desc_str.replace("</li>", "<br/>")
-        return html2plaintext(desc_str)
+    def _get_customer_description(self):
+        """:return (str): The description to include in calendar exports"""
+        return html2plaintext(self.description) if self.description else ''
+
+    def _get_customer_summary(self):
+        """:return (str): The summary to include in calendar exports"""
+        return self.name or ''
 
     @api.model
     def _get_display_time(self, start, stop, zduration, zallday):