Add Post Processing to process_record (#4892)

* Improve process_record system

Code based on @colinta's

* Rename and better handle functions

* Fix incorrect function call to process_record_user

* Add documentation for post_process_record

* Add both get_event_keycode and get_record_keycode functions

And add some comments about these functions

* Update code format

* Cleanup merge artifacts

1 files changed, 15 insertions, 5 deletions

diff --git a/quantum/quantum.c b/quantum/quantum.c
index b31c98852c..354fa480bb 100644
--- a/quantum/quantum.c
+++ b/quantum/quantum.c
@@ -117,6 +117,10 @@ __attribute__((weak)) bool process_record_kb(uint16_t keycode, keyrecord_t *reco
 
 __attribute__((weak)) bool process_record_user(uint16_t keycode, keyrecord_t *record) { return true; }
 
+__attribute__((weak)) void post_process_record_kb(uint16_t keycode, keyrecord_t *record) { post_process_record_user(keycode, record); }
+
+__attribute__((weak)) void post_process_record_user(uint16_t keycode, keyrecord_t *record) {}
+
 void reset_keyboard(void) {
     clear_keyboard();
 #if defined(MIDI_ENABLE) && defined(MIDI_BASIC)
@@ -169,9 +173,15 @@ uint16_t get_event_keycode(keyevent_t event) {
         return keymap_key_to_keycode(layer_switch_get_layer(event.key), event.key);
 }
 
-/* Main keycode processing function. Hands off handling to other functions,
- * then processes internal Quantum keycodes, then processes ACTIONs.
- */
+/* Get keycode, and then call keyboard function */
+void post_process_record_quantum(keyrecord_t *record) {
+    uint16_t keycode = get_record_keycode(record);
+    post_process_record_kb(keycode, record);
+}
+
+/* Core keycode function, hands off handling to other functions,
+    then processes internal quantum keycodes, and then processes
+    ACTIONs.                                                      */
 bool process_record_quantum(keyrecord_t *record) {
     uint16_t keycode = get_record_keycode(record);
 
@@ -191,7 +201,7 @@ bool process_record_quantum(keyrecord_t *record) {
 
 #ifdef WPM_ENABLE
     if (record->event.pressed) {
-	update_wpm(keycode);
+        update_wpm(keycode);
     }
 #endif
 
@@ -665,7 +675,7 @@ void matrix_scan_quantum() {
 #endif
 
 #ifdef WPM_ENABLE
-  decay_wpm();
+    decay_wpm();
 #endif
 
 #ifdef HAPTIC_ENABLE