[PRF] mail: improve performance of closing activities

MailActivity model has an ``_action_done`` method that is quite heavily
used and overridden. It notably posts messages, create next activities but
also has some specific behavior depending on category.

Purpose of this commit is to improve code of this method to avoid useless
queries, improve performance, and rethink the computation with batch in
mind.

Task-2883589 (Activity performance and cleaning)

Part-of: odoo/odoo#93682

addons/calendar/models/mail_activity.py

@@ -24,17 +24,15 @@ class MailActivity(models.Model):
         return action
 
     def _action_done(self, feedback=False, attachment_ids=False):
-        events = self.mapped('calendar_event_id')
-        messages, activities = super(MailActivity, self)._action_done(feedback=feedback, attachment_ids=attachment_ids)
         if feedback:
-            for event in events:
+            for event in self.calendar_event_id:
                 description = event.description
                 description = '%s<br />%s' % (
                     description if not tools.is_html_empty(description) else '',
                     _('Feedback: %(feedback)s', feedback=tools.plaintext2html(feedback)) if feedback else '',
                 )
                 event.write({'description': description})
-        return messages, activities
+        return super(MailActivity, self)._action_done(feedback=feedback, attachment_ids=attachment_ids)
 
     def unlink_w_meeting(self):
         events = self.mapped('calendar_event_id')

addons/mail/models/mail_activity.py

@@ -557,40 +557,44 @@ class MailActivity(models.Model):
             activity_id = attachment['res_id']
             activity_attachments[activity_id].append(attachment['id'])
 
-        for activity in self:
-            # extract value to generate next activities
-            if activity.chaining_type == 'trigger':
-                vals = activity.with_context(activity_previous_deadline=activity.date_deadline)._prepare_next_activity_values()
-                next_activities_values.append(vals)
+        for model, activity_data in self._classify_by_model().items():
+            records = self.env[model].browse(activity_data['record_ids'])
+            for record, activity in zip(records, activity_data['activities']):
+                # extract value to generate next activities
+                if activity.chaining_type == 'trigger':
+                    vals = activity.with_context(activity_previous_deadline=activity.date_deadline)._prepare_next_activity_values()
+                    next_activities_values.append(vals)
 
-            # post message on activity, before deleting it
-            record = self.env[activity.res_model].browse(activity.res_id)
-            record.message_post_with_view(
-                'mail.message_activity_done',
-                values={
-                    'activity': activity,
-                    'feedback': feedback,
-                    'display_assignee': activity.user_id != self.env.user
-                },
-                subtype_id=self.env['ir.model.data']._xmlid_to_res_id('mail.mt_activities'),
-                mail_activity_type_id=activity.activity_type_id.id,
-                attachment_ids=[Command.link(attachment_id) for attachment_id in attachment_ids] if attachment_ids else [],
-            )
+                # post message on activity, before deleting it
+                _, activity_message = record.message_post_with_view(
+                    'mail.message_activity_done',
+                    values={
+                        'activity': activity,
+                        'feedback': feedback,
+                        'display_assignee': activity.user_id != self.env.user
+                    },
+                    subtype_id=self.env['ir.model.data']._xmlid_to_res_id('mail.mt_activities'),
+                    mail_activity_type_id=activity.activity_type_id.id,
+                    attachment_ids=[Command.link(attachment_id) for attachment_id in attachment_ids] if attachment_ids else [],
+                )
 
-            # Moving the attachments in the message
-            # TODO: Fix void res_id on attachment when you create an activity with an image
-            # directly, see route /web_editor/attachment/add
-            activity_message = record.message_ids[0]
-            message_attachments = self.env['ir.attachment'].browse(activity_attachments[activity.id])
-            if message_attachments:
-                message_attachments.write({
-                    'res_id': activity_message.id,
-                    'res_model': activity_message._name,
-                })
-                activity_message.attachment_ids = message_attachments
-            messages += activity_message
+                # Moving the attachments in the message
+                # TODO: Fix void res_id on attachment when you create an activity with an image
+                # directly, see route /web_editor/attachment/add
+                if activity_attachments[activity.id]:
+                    message_attachments = self.env['ir.attachment'].browse(activity_attachments[activity.id])
+                    if message_attachments:
+                        message_attachments.write({
+                            'res_id': activity_message.id,
+                            'res_model': activity_message._name,
+                        })
+                        activity_message.attachment_ids = message_attachments
+                messages += activity_message
+
+        next_activities = self.env['mail.activity']
+        if next_activities_values:
+            next_activities = self.env['mail.activity'].create(next_activities_values)
 
-        next_activities = self.env['mail.activity'].create(next_activities_values)
         self.unlink()  # will unlink activity, dont access `self` after that
 
         return messages, next_activities