[FIX] mail: make Inbox counters more reliable in mark as read flows

- Send the new Inbox counter when marking as read, to guarantee the JS has the
  correct value (instead of having to guess it which was impossible when an
  arbitrary domain was given to the method).

  NOTE: Manual increment is kept on receiving a new Inbox message because that
  one was reliable and it would have been more tricky to compute the new counter
  for each target partner (mark as read is one user doing an action for himself,
  whereas new message is from another user to potentially many different users).
  Generic counter for threads is also not sent on every change for similar
  reasons.

- Refresh Inbox automatically when some messages are marked as read and there
  are more message on the server than currently loaded.

- Remove confusing (and impossible to maintain) counter on non-origin threads
  (in particular channel followers). This behavior in JS was not consistent with
  the server which always counted only origin thread (model/res_id).

task-2446302

closes odoo/odoo#65161

Signed-off-by: Alexandre Kühn (aku) <aku@odoo.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/addons/mail/static/src/model/model_field_command.js b/addons/mail/static/src/model/model_field_command.js
index 89f42651ad9..a6dadb7b983 100644
--- a/addons/mail/static/src/model/model_field_command.js
+++ b/addons/mail/static/src/model/model_field_command.js
@@ -35,11 +35,37 @@ function clear() {
     );
 }
 
+/**
+ * Returns a decrement command to give to the model manager at create/update.
+ *
+ * @param {number} [amount=1]
+ */
+function decrement(amount = 1) {
+    return new FieldCommand((field, record, options) => {
+        const oldValue = field.get(record);
+        field.set(record, oldValue - amount, options);
+    });
+}
+
+/**
+ * Returns a increment command to give to the model manager at create/update.
+ *
+ * @param {number} [amount=1]
+ */
+function increment(amount = 1) {
+    return new FieldCommand((field, record, options) => {
+        const oldValue = field.get(record);
+        field.set(record, oldValue + amount, options);
+    });
+}
+
 return {
     // class
     FieldCommand,
     // shortcuts
     clear,
+    decrement,
+    increment,
 };
 
 });