[Core] Add Repeat Key ("repeat last key") as a core feature. (#19700)

Co-authored-by: casuanoob <96005765+casuanoob@users.noreply.github.com>
Co-authored-by: Sergey Vlasov <sigprof@gmail.com>

1 files changed, 109 insertions, 0 deletions

diff --git a/quantum/process_keycode/process_repeat_key.c b/quantum/process_keycode/process_repeat_key.c
new file mode 100644
index 0000000000..f819aa226e
--- /dev/null
+++ b/quantum/process_keycode/process_repeat_key.c
@@ -0,0 +1,109 @@
+// Copyright 2022-2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "process_repeat_key.h"
+
+// Default implementation of remember_last_key_user().
+__attribute__((weak)) bool remember_last_key_user(uint16_t keycode, keyrecord_t* record, uint8_t* remembered_mods) {
+    return true;
+}
+
+static bool remember_last_key(uint16_t keycode, keyrecord_t* record, uint8_t* remembered_mods) {
+    switch (keycode) {
+        // Ignore MO, TO, TG, TT, and TL layer switch keys.
+        case QK_MOMENTARY ... QK_MOMENTARY_MAX:
+        case QK_TO ... QK_TO_MAX:
+        case QK_TOGGLE_LAYER ... QK_TOGGLE_LAYER_MAX:
+        case QK_LAYER_TAP_TOGGLE ... QK_LAYER_TAP_TOGGLE_MAX:
+        // Ignore mod keys.
+        case KC_LCTL ... KC_RGUI:
+        case KC_HYPR:
+        case KC_MEH:
+#ifndef NO_ACTION_ONESHOT // Ignore one-shot keys.
+        case QK_ONE_SHOT_LAYER ... QK_ONE_SHOT_LAYER_MAX:
+        case QK_ONE_SHOT_MOD ... QK_ONE_SHOT_MOD_MAX:
+#endif                  // NO_ACTION_ONESHOT
+#ifdef TRI_LAYER_ENABLE // Ignore Tri Layer keys.
+        case QK_TRI_LAYER_LOWER:
+        case QK_TRI_LAYER_UPPER:
+#endif // TRI_LAYER_ENABLE
+            return false;
+
+            // Ignore hold events on tap-hold keys.
+#ifndef NO_ACTION_TAPPING
+        case QK_MOD_TAP ... QK_MOD_TAP_MAX:
+#    ifndef NO_ACTION_LAYER
+        case QK_LAYER_TAP ... QK_LAYER_TAP_MAX:
+#    endif // NO_ACTION_LAYER
+            if (record->tap.count == 0) {
+                return false;
+            }
+            break;
+#endif // NO_ACTION_TAPPING
+
+#ifdef SWAP_HANDS_ENABLE
+        case QK_SWAP_HANDS ... QK_SWAP_HANDS_MAX:
+            if (IS_SWAP_HANDS_KEYCODE(keycode) || record->tap.count == 0) {
+                return false;
+            }
+            break;
+#endif // SWAP_HANDS_ENABLE
+
+        case QK_REPEAT_KEY:
+#ifndef NO_ALT_REPEAT_KEY
+        case QK_ALT_REPEAT_KEY:
+#endif // NO_ALT_REPEAT_KEY
+            return false;
+    }
+
+    return remember_last_key_user(keycode, record, remembered_mods);
+}
+
+bool process_last_key(uint16_t keycode, keyrecord_t* record) {
+    if (get_repeat_key_count()) {
+        return true;
+    }
+
+    if (record->event.pressed) {
+        uint8_t remembered_mods = get_mods() | get_weak_mods();
+#ifndef NO_ACTION_ONESHOT
+        remembered_mods |= get_oneshot_mods();
+#endif // NO_ACTION_ONESHOT
+
+        if (remember_last_key(keycode, record, &remembered_mods)) {
+            set_last_record(keycode, record);
+            set_last_mods(remembered_mods);
+        }
+    }
+
+    return true;
+}
+
+bool process_repeat_key(uint16_t keycode, keyrecord_t* record) {
+    if (get_repeat_key_count()) {
+        return true;
+    }
+
+    if (keycode == QK_REPEAT_KEY) {
+        repeat_key_invoke(&record->event);
+        return false;
+#ifndef NO_ALT_REPEAT_KEY
+    } else if (keycode == QK_ALT_REPEAT_KEY) {
+        alt_repeat_key_invoke(&record->event);
+        return false;
+#endif // NO_ALT_REPEAT_KEY
+    }
+
+    return true;
+}