Index: openacs-4/packages/acs-mail-lite/tcl/email-inbound-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-mail-lite/tcl/email-inbound-procs.tcl,v
diff -u -r1.12 -r1.13
--- openacs-4/packages/acs-mail-lite/tcl/email-inbound-procs.tcl	14 Jun 2018 22:16:08 -0000	1.12
+++ openacs-4/packages/acs-mail-lite/tcl/email-inbound-procs.tcl	21 Jun 2018 15:45:03 -0000	1.13
@@ -2440,6 +2440,92 @@
     return $ignore_p
 }
 
+ad_proc -private acs_mail_lite::bounce_prefix {} {
+    @return bounce prefix for x-envelope-from
+} {
+    return [parameter::get_from_package_key -package_key "acs-mail-lite" -parameter "EnvelopePrefix"]
+}
+
+ad_proc -public acs_mail_lite::bouncing_user_p {
+    -user_id:required
+} {
+    Checks if email address of user is bouncing mail
+    @option user_id user to be checked for bouncing
+    @return boolean 1 if bouncing 0 if ok.
+} {
+    return [acs_user::get_element \
+                -user_id $user_id \
+                -element email_bouncing_p]
+}
+
+
+ad_proc -private acs_mail_lite::check_bounces {} {
+    Daily proc that sends out warning mail that emails
+    are bouncing and disables emails if necessary
+} {
+    set package_id [apm_package_id_from_key "acs-mail-lite"]
+    set max_bounce_count [parameter::get -package_id $package_id -parameter MaxBounceCount -default 10]
+    set max_days_to_bounce [parameter::get -package_id $package_id -parameter MaxDaysToBounce -default 3]
+    set notification_interval [parameter::get -package_id $package_id -parameter NotificationInterval -default 7]
+    set max_notification_count [parameter::get -package_id $package_id -parameter MaxNotificationCount -default 4]
+    set notification_sender [parameter::get -package_id $package_id -parameter NotificationSender -default "reminder@[address_domain]"]
+    if { $notification_sender eq "" } {
+        # Use the most specific default available
+        set fixed_sender [parameter::get -package_id $package_id -parameter "FixedSenderEmail"]
+        if { $fixed_sender ne "" } {
+            set notification_sender $fixed_sender
+        } elseif { [acs_mail_lite::utils::valid_email_p [ad_system_owner]] } {
+            set notification_sender [ad_system_owner]
+        } else {
+            # Set to an email address that is required to exist
+            # to avoid email loops and other issues
+            # per RFC 5321 section 4.5.1
+            # https://tools.ietf.org/html/rfc5321#section-4.5.1
+            # The somewhat unique capitalization may be useful
+            # for identifyng source in diagnostic context.
+            set notification_sender "PostMastER@[address_domain]"
+        }
+    }
+
+    # delete all bounce-log-entries for users who received last email
+    # X days ago without any bouncing (parameter)
+    db_dml delete_log_if_no_recent_bounce {}
+
+    # disable mail sending for users with more than X recently
+    # bounced mails
+    db_dml disable_bouncing_email {}
+
+    # notify users of this disabled mail sending
+    db_dml send_notification_to_bouncing_email {}
+
+    # now delete bounce log for users with disabled mail sending
+    db_dml delete_bouncing_users_from_log {}
+
+    set subject "[ad_system_name] Email Reminder"
+
+    # now periodically send notifications to users with
+    # disabled email to tell them how to re-enable the email
+    set notifications [db_list_of_ns_sets get_recent_bouncing_users {}]
+
+    # send notification to users with disabled email
+    foreach notification $notifications {
+        set notification_list [util_ns_set_to_list -set $notification]
+        array set user $notification_list
+        set user_id $user(user_id)
+        set href [export_vars -base [ad_url]/register/restore-bounce {user_id}]
+        set body "Dear $user(name),\n\n\
+Due to returning mails from your email account, \n \
+we currently do not send you any email from our system.\n\n \
+To re-enable your email notifications, please visit\n${href}"
+
+        send -to_addr $notification_list -from_addr $notification_sender -subject $subject -body $body -valid_email
+        ns_log Notice "Bounce notification send to user $user_id"
+
+        # schedule next notification
+        db_dml log_notification_sending {}
+    }
+}
+
 #
 # Local variables:
 #    mode: tcl