Major mod-tap improvements.

* Track active mods when mods or keycode
  events occur.
* Use the tracked mods when releasing or
  generating keycode events.
* Track pending/used status in one array, for
  improved storage efficency.

1 files changed, 123 insertions, 88 deletions

diff --git a/app/src/behaviors/behavior_mod_tap.c b/app/src/behaviors/behavior_mod_tap.c
index df3eec2..b7d4f4e 100644
--- a/app/src/behaviors/behavior_mod_tap.c
+++ b/app/src/behaviors/behavior_mod_tap.c
@@ -33,16 +33,22 @@ LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
         break;                             \
     }
 
-struct pending_mod_tap_item {
+struct active_mod_tap_item {
   u32_t keycode;
   u8_t mods;
+  bool pending;
+  zmk_mod_flags active_mods;
+};
+
+struct captured_keycode_state_change_item {
+  struct keycode_state_changed* event;
+  zmk_mod_flags active_mods;
 };
 
 struct behavior_mod_tap_config { };
 struct behavior_mod_tap_data {
-  struct pending_mod_tap_item pending_mod_taps[ZMK_BHV_MOD_TAP_MAX_HELD];
-  struct pending_mod_tap_item triggered_mod_taps[ZMK_BHV_MOD_TAP_MAX_HELD];
-  struct keycode_state_changed* pending_key_presses[ZMK_BHV_MOD_TAP_MAX_PENDING_KC];
+  struct active_mod_tap_item active_mod_taps[ZMK_BHV_MOD_TAP_MAX_HELD];
+  struct captured_keycode_state_change_item captured_keycode_events[ZMK_BHV_MOD_TAP_MAX_PENDING_KC];
 };
 
 bool have_pending_mods(char *label) {
@@ -50,8 +56,8 @@ bool have_pending_mods(char *label) {
   struct behavior_mod_tap_data *data = dev->driver_data;
 
   for (int i = 0; i < ZMK_BHV_MOD_TAP_MAX_HELD; i++) {
-    if (data->pending_mod_taps[i].mods) {
-      LOG_DBG("Found pending mods for %d and keycode 0x%02X", data->pending_mod_taps[i].mods, data->pending_mod_taps[i].keycode);
+    if (data->active_mod_taps[i].mods) {
+      LOG_DBG("Found pending mods for %d and keycode 0x%02X", data->active_mod_taps[i].mods, data->active_mod_taps[i].keycode);
       return true;
     }
   }
@@ -59,19 +65,54 @@ bool have_pending_mods(char *label) {
   return false;
 }
 
-bool have_pending_keycode(struct behavior_mod_tap_data *data, u32_t keycode)
+struct captured_keycode_state_change_item* find_pending_keycode(struct behavior_mod_tap_data *data, u32_t keycode)
 {
   for (int i = 0; i < ZMK_BHV_MOD_TAP_MAX_PENDING_KC; i++) {
-    if (data->pending_key_presses[i] == NULL) {
+    if (data->captured_keycode_events[i].event == NULL) {
       continue;
     }
 
-    if (data->pending_key_presses[i]->keycode == keycode) {
-      return true;
+    if (data->captured_keycode_events[i].event->keycode == keycode) {
+      return &data->captured_keycode_events[i];
     }
   }
 
-  return false;
+  return NULL;
+}
+
+zmk_mod_flags behavior_mod_tap_active_mods(struct behavior_mod_tap_data *data)
+{
+  zmk_mod_flags mods = 0;
+
+  for (int i = 0; i < ZMK_BHV_MOD_TAP_MAX_HELD; i++) {
+    mods |= data->active_mod_taps[i].mods;
+  }
+
+  return mods;
+}
+
+int behavior_mod_tap_capture_keycode_event(struct behavior_mod_tap_data *data, struct keycode_state_changed *ev)
+{
+  for (int i = 0; i < ZMK_BHV_MOD_TAP_MAX_PENDING_KC; i++) {
+    if (data->captured_keycode_events[i].event != NULL) {
+      continue;
+    }
+
+    data->captured_keycode_events[i].event = ev;
+    data->captured_keycode_events[i].active_mods = behavior_mod_tap_active_mods(data);
+    return 0;
+  }
+
+  return -ENOMEM;
+}
+
+void behavior_mod_tap_update_active_mods_state(struct behavior_mod_tap_data *data, zmk_mod_flags used_flags)
+{
+  for (int i = 0; i < ZMK_BHV_MOD_TAP_MAX_HELD; i++) {
+    if ((data->active_mod_taps[i].mods & used_flags) == data->active_mod_taps[i].mods) {
+      data->active_mod_taps[i].pending = false;
+    }
+  }
 }
 
 // How to pass context to subscription?!
@@ -81,39 +122,25 @@ int behavior_mod_tap_listener(const struct zmk_event_header *eh)
     struct device *dev = device_get_binding(DT_INST_LABEL(0));
     struct keycode_state_changed *ev = cast_keycode_state_changed(eh);
     struct behavior_mod_tap_data *data = dev->driver_data;
+    struct captured_keycode_state_change_item* pending_keycode;
     if (ev->state) {
       LOG_DBG("Have pending mods, capturing keycode 0x%02X event to ressend later", ev->keycode);
-      TOGGLE_FIRST(data->pending_key_presses, ZMK_BHV_MOD_TAP_MAX_PENDING_KC, NULL, ev);
+      behavior_mod_tap_capture_keycode_event(data, ev);
       return ZMK_EV_EVENT_CAPTURED;
-    } else if (have_pending_keycode(data, ev->keycode)) {
-      zmk_mod_flags mods = 0;
-
+    } else if ((pending_keycode = find_pending_keycode(data, ev->keycode)) != NULL) {
       LOG_DBG("Key released, going to activate mods then send pending key presses");
-      for (int i = 0; i < ZMK_BHV_MOD_TAP_MAX_HELD; i++) {
-        memcpy(&data->triggered_mod_taps[i], &data->pending_mod_taps[i], sizeof(struct pending_mod_tap_item));
-        data->pending_mod_taps[i].mods = 0;
-        data->pending_mod_taps[i].keycode = 0;
-      }
-      LOG_DBG("After swapping, do I have pending mods? %s", (have_pending_mods(DT_INST_LABEL(0)) ? "true" : "false"));
 
-      for (int i = 0; i < ZMK_BHV_MOD_TAP_MAX_HELD; i++) {
-        mods |= data->triggered_mod_taps[i].mods;
-      }
 
-      LOG_DBG("Setting mods: %d", mods);
+      LOG_DBG("Setting mods: %d", pending_keycode->active_mods);
 
-      zmk_hid_register_mods(mods);
+      zmk_hid_register_mods(pending_keycode->active_mods);
+      behavior_mod_tap_update_active_mods_state(data, pending_keycode->active_mods);
 
-      for (int i = 0; i < ZMK_BHV_MOD_TAP_MAX_PENDING_KC; i++) {
-        if (data->pending_key_presses[i] == NULL) {
-          continue;
-        }
+      ZMK_EVENT_RELEASE(pending_keycode->event);
+      k_msleep(10);
 
-        struct keycode_state_changed *ev = data->pending_key_presses[i];
-        data->pending_key_presses[i] = NULL;
-        ZMK_EVENT_RAISE(ev);
-        k_msleep(10);
-      }
+      pending_keycode->event = NULL;
+      pending_keycode->active_mods = 0;
     }
   }
   return 0;
@@ -133,82 +160,90 @@ static int on_keymap_binding_pressed(struct device *dev, u32_t position, u32_t m
   struct behavior_mod_tap_data *data = dev->driver_data;
   LOG_DBG("mods: %d, keycode: 0x%02X", mods, keycode);
   for (int i = 0; i < ZMK_BHV_MOD_TAP_MAX_HELD; i++) {
-    if (data->pending_mod_taps[i].mods != 0) {
+    if (data->active_mod_taps[i].mods != 0) {
       continue;
     }
 
-    data->pending_mod_taps[i].mods = mods;
-    data->pending_mod_taps[i].keycode = keycode;
+    zmk_mod_flags active_mods = behavior_mod_tap_active_mods(data);
+
+    data->active_mod_taps[i].active_mods = active_mods;
+    data->active_mod_taps[i].mods = mods;
+    data->active_mod_taps[i].keycode = keycode;
+    data->active_mod_taps[i].pending = true;
 
     return 0;
   }
 
+  LOG_WRN("Failed to record mod-tap activation, at maximum concurrent mod-tap activations");
+
   return -ENOMEM;
 }
 
 static int on_keymap_binding_released(struct device *dev, u32_t position, u32_t mods, u32_t keycode)
 {
   struct behavior_mod_tap_data *data = dev->driver_data;
-  bool sending_keycode = false;
-  bool sent_pending_key_presses = false;
-  struct keycode_state_changed *pending_key_presses[ZMK_BHV_MOD_TAP_MAX_PENDING_KC];
   LOG_DBG("mods: %d, keycode: %d", mods, keycode);
   
   for (int i = 0; i < ZMK_BHV_MOD_TAP_MAX_HELD; i++) {
-    if (data->triggered_mod_taps[i].mods == mods && data->triggered_mod_taps[i].keycode == keycode) {
-      LOG_DBG("Releasing triggered mods: %d", mods);
-      zmk_hid_unregister_mods(mods);
-      data->triggered_mod_taps[i].mods = 0;
-      data->triggered_mod_taps[i].keycode = 0;
-      break;
-    }
-  }
-
-  for (int i = 0; i < ZMK_BHV_MOD_TAP_MAX_HELD; i++) {
-    if (data->pending_mod_taps[i].mods == mods && data->pending_mod_taps[i].keycode == keycode) {
-      sending_keycode = true;
-      data->pending_mod_taps[i].mods = 0;
-      data->pending_mod_taps[i].keycode = 0;
-      break;
-    }
-  }
-
-  for (int i = 0; i < ZMK_BHV_MOD_TAP_MAX_PENDING_KC; i++) {
-    pending_key_presses[i] = data->pending_key_presses[i];
-    data->pending_key_presses[i] = NULL;
-  }
+    struct active_mod_tap_item *item = &data->active_mod_taps[i];
+    if (item->mods == mods && item->keycode == keycode) {
+      if (item->pending) {
+        LOG_DBG("Sending un-triggered mod-tap for keycode: 0x%02X", keycode);
+
+        if (item->active_mods) {
+          LOG_DBG("Registering recorded active mods captured when mod-tap initially activated: 0x%02X", item->active_mods);
+          behavior_mod_tap_update_active_mods_state(data, item->active_mods);
+          zmk_hid_register_mods(item->active_mods);
+        }
 
+        struct keycode_state_changed *key_press = create_keycode_state_changed(USAGE_KEYPAD, item->keycode, true);
+        ZMK_EVENT_RAISE_AFTER(key_press, behavior_mod_tap);
+        k_msleep(10);
 
-  if (sending_keycode) {
-      struct keycode_state_changed *key_press = create_keycode_state_changed(USAGE_KEYPAD, keycode, true);
-      LOG_DBG("Sending un-triggered mod-tap for keycode: 0x%02X", keycode);
-      ZMK_EVENT_RAISE(key_press);
-      k_msleep(10);
-  }
-  
+        for (int j = 0; j < ZMK_BHV_MOD_TAP_MAX_PENDING_KC; j++) {
+          if (data->captured_keycode_events[j].event == NULL) {
+            continue;
+          }
+
+          struct keycode_state_changed *ev = data->captured_keycode_events[j].event;
+          data->captured_keycode_events[i].event = NULL;
+          data->captured_keycode_events[i].active_mods = 0;
+          LOG_DBG("Re-sending latched key press for usage page 0x%02X keycode 0x%02X state %s", ev->usage_page, ev->keycode, (ev->state ? "pressed" : "released"));
+          ZMK_EVENT_RELEASE(ev);
+          k_msleep(10);
+        }
 
-  for (int i = 0; i < ZMK_BHV_MOD_TAP_MAX_PENDING_KC; i++) {
-    if (pending_key_presses[i] == NULL) {
-      continue;
-    }
+        struct keycode_state_changed *key_release = create_keycode_state_changed(USAGE_KEYPAD, keycode, false);
+        LOG_DBG("Sending un-triggered mod-tap release for keycode: 0x%02X", keycode);
+        ZMK_EVENT_RAISE_AFTER(key_release, behavior_mod_tap);
+        k_msleep(10);
 
-    struct keycode_state_changed *ev = pending_key_presses[i];
-    sent_pending_key_presses = true;
-    LOG_DBG("Re-sending latched key press for usage page 0x%02X keycode 0x%02X state %s", ev->usage_page, ev->keycode, (ev->state ? "pressed" : "released"));
-    ZMK_EVENT_RELEASE(ev);
-    k_msleep(10);
-  }
+        if (item->active_mods) {
+          LOG_DBG("Unregistering recorded active mods captured when mod-tap initially activated: 0x%02X", item->active_mods);
+          zmk_hid_unregister_mods(item->active_mods);
+          zmk_endpoints_send_report(USAGE_KEYPAD);
+        }
 
-  if (sending_keycode) {
-      struct keycode_state_changed *key_release = create_keycode_state_changed(USAGE_KEYPAD, keycode, false);
-      LOG_DBG("Sending un-triggered mod-tap release for keycode: 0x%02X", keycode);
-      ZMK_EVENT_RAISE(key_release);
-  }
+        
+      } else {
+        LOG_DBG("Releasing triggered mods: %d", mods);
+        zmk_hid_unregister_mods(mods);
+        zmk_endpoints_send_report(USAGE_KEYPAD);
+      }
 
-  if (!sending_keycode && !sent_pending_key_presses) {
-    // Need to ensure the mod release is propagated.
-    zmk_endpoints_send_report(USAGE_KEYPAD);
+      item->mods = 0;
+      item->keycode = 0;
+      item->active_mods = 0;
 
+      LOG_DBG("Removing mods %d from active_mods for other held mod-taps", mods);
+      for (int j = 0; j < ZMK_BHV_MOD_TAP_MAX_HELD; j++) {
+        if (data->active_mod_taps[j].active_mods & mods) {
+          LOG_DBG("Removing 0x%02X from active mod tap mods 0x%02X keycode 0x%02X", mods, data->active_mod_taps[j].mods, data->active_mod_taps[j].keycode);
+          data->active_mod_taps[j].active_mods &= ~mods;
+        }
+      }
+      break;
+    }
   }
 
   return 0;