zmk_mf68/app/src/combo.c

497 lines
18 KiB
C

/*
* Copyright (c) 2020 The ZMK Contributors
*
* SPDX-License-Identifier: MIT
*/
#define DT_DRV_COMPAT zmk_combos
#include <device.h>
#include <drivers/behavior.h>
#include <logging/log.h>
#include <sys/dlist.h>
#include <kernel.h>
#include <zmk/behavior.h>
#include <zmk/event_manager.h>
#include <zmk/events/position_state_changed.h>
#include <zmk/hid.h>
#include <zmk/matrix.h>
#include <zmk/keymap.h>
LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
#if DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT)
struct combo_cfg {
int32_t key_positions[CONFIG_ZMK_COMBO_MAX_KEYS_PER_COMBO];
int32_t key_position_len;
struct zmk_behavior_binding behavior;
int32_t timeout_ms;
// if slow release is set, the combo releases when the last key is released.
// otherwise, the combo releases when the first key is released.
bool slow_release;
// the virtual key position is a key position outside the range used by the keyboard.
// it is necessary so hold-taps can uniquely identify a behavior.
int32_t virtual_key_position;
int32_t layers_len;
int8_t layers[];
};
struct active_combo {
struct combo_cfg *combo;
// key_positions_pressed is filled with key_positions when the combo is pressed.
// The keys are removed from this array when they are released.
// Once this array is empty, the behavior is released.
const zmk_event_t *key_positions_pressed[CONFIG_ZMK_COMBO_MAX_KEYS_PER_COMBO];
};
struct combo_candidate {
struct combo_cfg *combo;
// the time after which this behavior should be removed from candidates.
// by keeping track of when the candidate should be cleared there is no
// possibility of accidental releases.
int64_t timeout_at;
};
// set of keys pressed
const zmk_event_t *pressed_keys[CONFIG_ZMK_COMBO_MAX_KEYS_PER_COMBO] = {NULL};
// the set of candidate combos based on the currently pressed_keys
struct combo_candidate candidates[CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY];
// the last candidate that was completely pressed
struct combo_cfg *fully_pressed_combo = NULL;
// a lookup dict that maps a key position to all combos on that position
struct combo_cfg *combo_lookup[ZMK_KEYMAP_LEN][CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY] = {NULL};
// combos that have been activated and still have (some) keys pressed
// this array is always contiguous from 0.
struct active_combo active_combos[CONFIG_ZMK_COMBO_MAX_PRESSED_COMBOS] = {NULL};
int active_combo_count = 0;
struct k_work_delayable timeout_task;
int64_t timeout_task_timeout_at;
// Store the combo key pointer in the combos array, one pointer for each key position
// The combos are sorted shortest-first, then by virtual-key-position.
static int initialize_combo(struct combo_cfg *new_combo) {
for (int i = 0; i < new_combo->key_position_len; i++) {
int32_t position = new_combo->key_positions[i];
if (position >= ZMK_KEYMAP_LEN) {
LOG_ERR("Unable to initialize combo, key position %d does not exist", position);
return -EINVAL;
}
struct combo_cfg *insert_combo = new_combo;
bool set = false;
for (int j = 0; j < CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY; j++) {
struct combo_cfg *combo_at_j = combo_lookup[position][j];
if (combo_at_j == NULL) {
combo_lookup[position][j] = insert_combo;
set = true;
break;
}
if (combo_at_j->key_position_len < insert_combo->key_position_len ||
(combo_at_j->key_position_len == insert_combo->key_position_len &&
combo_at_j->virtual_key_position < insert_combo->virtual_key_position)) {
continue;
}
// put insert_combo in this spot, move all other combos up.
combo_lookup[position][j] = insert_combo;
insert_combo = combo_at_j;
}
if (!set) {
LOG_ERR("Too many combos for key position %d, CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY %d.",
position, CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY);
return -ENOMEM;
}
}
return 0;
}
static bool combo_active_on_layer(struct combo_cfg *combo, uint8_t layer) {
if (combo->layers[0] == -1) {
// -1 in the first layer position is global layer scope
return true;
}
for (int j = 0; j < combo->layers_len; j++) {
if (combo->layers[j] == layer) {
return true;
}
}
return false;
}
static int setup_candidates_for_first_keypress(int32_t position, int64_t timestamp) {
int number_of_combo_candidates = 0;
uint8_t highest_active_layer = zmk_keymap_highest_layer_active();
for (int i = 0; i < CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY; i++) {
struct combo_cfg *combo = combo_lookup[position][i];
if (combo == NULL) {
return number_of_combo_candidates;
}
if (combo_active_on_layer(combo, highest_active_layer)) {
candidates[number_of_combo_candidates].combo = combo;
candidates[number_of_combo_candidates].timeout_at = timestamp + combo->timeout_ms;
number_of_combo_candidates++;
}
// LOG_DBG("combo timeout %d %d %d", position, i, candidates[i].timeout_at);
}
return number_of_combo_candidates;
}
static int filter_candidates(int32_t position) {
// this code iterates over candidates and the lookup together to filter in O(n)
// assuming they are both sorted on key_position_len, virtal_key_position
int matches = 0, lookup_idx = 0, candidate_idx = 0;
while (lookup_idx < CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY &&
candidate_idx < CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY) {
struct combo_cfg *candidate = candidates[candidate_idx].combo;
struct combo_cfg *lookup = combo_lookup[position][lookup_idx];
if (candidate == NULL || lookup == NULL) {
break;
}
if (candidate->virtual_key_position == lookup->virtual_key_position) {
candidates[matches] = candidates[candidate_idx];
matches++;
candidate_idx++;
lookup_idx++;
} else if (candidate->key_position_len > lookup->key_position_len) {
lookup_idx++;
} else if (candidate->key_position_len < lookup->key_position_len) {
candidate_idx++;
} else if (candidate->virtual_key_position > lookup->virtual_key_position) {
lookup_idx++;
} else if (candidate->virtual_key_position < lookup->virtual_key_position) {
candidate_idx++;
}
}
// clear unmatched candidates
for (int i = matches; i < CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY; i++) {
candidates[i].combo = NULL;
}
// LOG_DBG("combo matches after filter %d", matches);
return matches;
}
static int64_t first_candidate_timeout() {
int64_t first_timeout = LONG_MAX;
for (int i = 0; i < CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY; i++) {
if (candidates[i].combo == NULL) {
break;
}
if (candidates[i].timeout_at < first_timeout) {
first_timeout = candidates[i].timeout_at;
}
}
return first_timeout;
}
static inline bool candidate_is_completely_pressed(struct combo_cfg *candidate) {
// this code assumes set(pressed_keys) <= set(candidate->key_positions)
// this invariant is enforced by filter_candidates
// since events may have been reraised after clearing one or more slots at
// the start of pressed_keys (see: release_pressed_keys), we have to check
// that each key needed to trigger the combo was pressed, not just the last.
for (int i = 0; i < candidate->key_position_len; i++) {
if (pressed_keys[i] == NULL) {
return false;
}
}
return true;
}
static int cleanup();
static int filter_timed_out_candidates(int64_t timestamp) {
int num_candidates = 0;
for (int i = 0; i < CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY; i++) {
struct combo_candidate *candidate = &candidates[i];
if (candidate->combo == NULL) {
break;
}
if (candidate->timeout_at > timestamp) {
// reorder candidates so they're contiguous
candidates[num_candidates].combo = candidate->combo;
candidates[num_candidates].timeout_at = candidate->timeout_at;
num_candidates++;
} else {
candidate->combo = NULL;
}
}
return num_candidates;
}
static int clear_candidates() {
for (int i = 0; i < CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY; i++) {
if (candidates[i].combo == NULL) {
return i;
}
candidates[i].combo = NULL;
}
return CONFIG_ZMK_COMBO_MAX_COMBOS_PER_KEY;
}
static int capture_pressed_key(const zmk_event_t *ev) {
for (int i = 0; i < CONFIG_ZMK_COMBO_MAX_KEYS_PER_COMBO; i++) {
if (pressed_keys[i] != NULL) {
continue;
}
pressed_keys[i] = ev;
return ZMK_EV_EVENT_CAPTURED;
}
return 0;
}
const struct zmk_listener zmk_listener_combo;
static int release_pressed_keys() {
for (int i = 0; i < CONFIG_ZMK_COMBO_MAX_KEYS_PER_COMBO; i++) {
const zmk_event_t *captured_event = pressed_keys[i];
if (pressed_keys[i] == NULL) {
return i;
}
pressed_keys[i] = NULL;
if (i == 0) {
LOG_DBG("combo: releasing position event %d",
as_zmk_position_state_changed(captured_event)->position);
ZMK_EVENT_RELEASE(captured_event)
} else {
// reprocess events (see tests/combo/fully-overlapping-combos-3 for why this is needed)
LOG_DBG("combo: reraising position event %d",
as_zmk_position_state_changed(captured_event)->position);
ZMK_EVENT_RAISE(captured_event);
}
}
return CONFIG_ZMK_COMBO_MAX_KEYS_PER_COMBO;
}
static inline int press_combo_behavior(struct combo_cfg *combo, int32_t timestamp) {
struct zmk_behavior_binding_event event = {
.position = combo->virtual_key_position,
.timestamp = timestamp,
};
return behavior_keymap_binding_pressed(&combo->behavior, event);
}
static inline int release_combo_behavior(struct combo_cfg *combo, int32_t timestamp) {
struct zmk_behavior_binding_event event = {
.position = combo->virtual_key_position,
.timestamp = timestamp,
};
return behavior_keymap_binding_released(&combo->behavior, event);
}
static void move_pressed_keys_to_active_combo(struct active_combo *active_combo) {
int combo_length = active_combo->combo->key_position_len;
for (int i = 0; i < combo_length; i++) {
active_combo->key_positions_pressed[i] = pressed_keys[i];
pressed_keys[i] = NULL;
}
// move any other pressed keys up
for (int i = 0; i + combo_length < CONFIG_ZMK_COMBO_MAX_KEYS_PER_COMBO; i++) {
if (pressed_keys[i + combo_length] == NULL) {
return;
}
pressed_keys[i] = pressed_keys[i + combo_length];
pressed_keys[i + combo_length] = NULL;
}
}
static struct active_combo *store_active_combo(struct combo_cfg *combo) {
for (int i = 0; i < CONFIG_ZMK_COMBO_MAX_PRESSED_COMBOS; i++) {
if (active_combos[i].combo == NULL) {
active_combos[i].combo = combo;
active_combo_count++;
return &active_combos[i];
}
}
LOG_ERR("Unable to store combo; already %d active. Increase "
"CONFIG_ZMK_COMBO_MAX_PRESSED_COMBOS",
CONFIG_ZMK_COMBO_MAX_PRESSED_COMBOS);
return NULL;
}
static void activate_combo(struct combo_cfg *combo) {
struct active_combo *active_combo = store_active_combo(combo);
if (active_combo == NULL) {
// unable to store combo
release_pressed_keys();
return;
}
move_pressed_keys_to_active_combo(active_combo);
press_combo_behavior(
combo, as_zmk_position_state_changed(active_combo->key_positions_pressed[0])->timestamp);
}
static void deactivate_combo(int active_combo_index) {
active_combo_count--;
if (active_combo_index != active_combo_count) {
memcpy(&active_combos[active_combo_index], &active_combos[active_combo_count],
sizeof(struct active_combo));
}
active_combos[active_combo_count].combo = NULL;
active_combos[active_combo_count] = (struct active_combo){0};
}
/* returns true if a key was released. */
static bool release_combo_key(int32_t position, int64_t timestamp) {
for (int combo_idx = 0; combo_idx < active_combo_count; combo_idx++) {
struct active_combo *active_combo = &active_combos[combo_idx];
bool key_released = false;
bool all_keys_pressed = true;
bool all_keys_released = true;
for (int i = 0; i < active_combo->combo->key_position_len; i++) {
if (active_combo->key_positions_pressed[i] == NULL) {
all_keys_pressed = false;
} else if (as_zmk_position_state_changed(active_combo->key_positions_pressed[i])
->position != position) {
all_keys_released = false;
} else { // not null and position matches
ZMK_EVENT_FREE(active_combo->key_positions_pressed[i]);
active_combo->key_positions_pressed[i] = NULL;
key_released = true;
}
}
if (key_released) {
if ((active_combo->combo->slow_release && all_keys_released) ||
(!active_combo->combo->slow_release && all_keys_pressed)) {
release_combo_behavior(active_combo->combo, timestamp);
}
if (all_keys_released) {
deactivate_combo(combo_idx);
}
return true;
}
}
return false;
}
static int cleanup() {
k_work_cancel_delayable(&timeout_task);
clear_candidates();
if (fully_pressed_combo != NULL) {
activate_combo(fully_pressed_combo);
fully_pressed_combo = NULL;
}
return release_pressed_keys();
}
static void update_timeout_task() {
int64_t first_timeout = first_candidate_timeout();
if (timeout_task_timeout_at == first_timeout) {
return;
}
if (first_timeout == LLONG_MAX) {
timeout_task_timeout_at = 0;
k_work_cancel_delayable(&timeout_task);
return;
}
if (k_work_schedule(&timeout_task, K_MSEC(first_timeout - k_uptime_get())) >= 0) {
timeout_task_timeout_at = first_timeout;
}
}
static int position_state_down(const zmk_event_t *ev, struct zmk_position_state_changed *data) {
int num_candidates;
if (candidates[0].combo == NULL) {
num_candidates = setup_candidates_for_first_keypress(data->position, data->timestamp);
if (num_candidates == 0) {
return 0;
}
} else {
filter_timed_out_candidates(data->timestamp);
num_candidates = filter_candidates(data->position);
}
update_timeout_task();
struct combo_cfg *candidate_combo = candidates[0].combo;
LOG_DBG("combo: capturing position event %d", data->position);
int ret = capture_pressed_key(ev);
switch (num_candidates) {
case 0:
cleanup();
return ret;
case 1:
if (candidate_is_completely_pressed(candidate_combo)) {
fully_pressed_combo = candidate_combo;
cleanup();
}
return ret;
default:
if (candidate_is_completely_pressed(candidate_combo)) {
fully_pressed_combo = candidate_combo;
}
return ret;
}
}
static int position_state_up(const zmk_event_t *ev, struct zmk_position_state_changed *data) {
int released_keys = cleanup();
if (release_combo_key(data->position, data->timestamp)) {
return ZMK_EV_EVENT_HANDLED;
}
if (released_keys > 1) {
// The second and further key down events are re-raised. To preserve
// correct order for e.g. hold-taps, reraise the key up event too.
ZMK_EVENT_RAISE(ev);
return ZMK_EV_EVENT_CAPTURED;
}
return 0;
}
static void combo_timeout_handler(struct k_work *item) {
if (timeout_task_timeout_at == 0 || k_uptime_get() < timeout_task_timeout_at) {
// timer was cancelled or rescheduled.
return;
}
if (filter_timed_out_candidates(timeout_task_timeout_at) < 2) {
cleanup();
}
update_timeout_task();
}
static int position_state_changed_listener(const zmk_event_t *ev) {
struct zmk_position_state_changed *data = as_zmk_position_state_changed(ev);
if (data == NULL) {
return 0;
}
if (data->state) { // keydown
return position_state_down(ev, data);
} else { // keyup
return position_state_up(ev, data);
}
}
ZMK_LISTENER(combo, position_state_changed_listener);
ZMK_SUBSCRIPTION(combo, zmk_position_state_changed);
#define COMBO_INST(n) \
static struct combo_cfg combo_config_##n = { \
.timeout_ms = DT_PROP(n, timeout_ms), \
.key_positions = DT_PROP(n, key_positions), \
.key_position_len = DT_PROP_LEN(n, key_positions), \
.behavior = ZMK_KEYMAP_EXTRACT_BINDING(0, n), \
.virtual_key_position = ZMK_KEYMAP_LEN + __COUNTER__, \
.slow_release = DT_PROP(n, slow_release), \
.layers = DT_PROP(n, layers), \
.layers_len = DT_PROP_LEN(n, layers), \
};
#define INITIALIZE_COMBO(n) initialize_combo(&combo_config_##n);
DT_INST_FOREACH_CHILD(0, COMBO_INST)
static int combo_init() {
k_work_init_delayable(&timeout_task, combo_timeout_handler);
DT_INST_FOREACH_CHILD(0, INITIALIZE_COMBO);
return 0;
}
SYS_INIT(combo_init, APPLICATION, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);
#endif