qmk-firmware/users/dennytom/chording_engine/engine.part.3

bool are_hashed_keycodes_in_sound(HASH_TYPE keycodes_hash, HASH_TYPE sound) {
    return (keycodes_hash & sound) == keycodes_hash;
}

uint8_t keycode_to_index(uint16_t keycode) {
    return keycode - FIRST_INTERNAL_KEYCODE;
}

void sound_keycode_array(uint16_t keycode) {
    uint8_t index = keycode_to_index(keycode);
    keycode_index++;
    keycodes_buffer_array[index] = keycode_index;
}

void silence_keycode_hash_array(HASH_TYPE keycode_hash) {
    for (int i = 0; i < NUMBER_OF_KEYS; i++) {
        bool index_in_hash = ((HASH_TYPE) 1 << i) & keycode_hash;
        if (index_in_hash) {
            uint8_t current_val = keycodes_buffer_array[i];
            keycodes_buffer_array[i] = 0;
            for (int j = 0; j < NUMBER_OF_KEYS; j++) {
                if (keycodes_buffer_array[j] > current_val) {
                    keycodes_buffer_array[j]--;
                }
            }
            keycode_index--;
        }
    }
}

bool are_hashed_keycodes_in_array(HASH_TYPE keycode_hash) {
    for (int i = 0; i < NUMBER_OF_KEYS; i++) {
        bool index_in_hash = ((HASH_TYPE) 1 << i) & keycode_hash;
        bool index_in_array = (bool) keycodes_buffer_array[i];
        if (index_in_hash && !index_in_array) {
            return false;
        }
    }
    return true;
}

void kill_one_shots(void) {
    struct Chord chord_storage;
    struct Chord* chord_ptr;
    struct Chord* chord;
    
    for (int i = 0; i < NUMBER_OF_CHORDS; i++) {
        chord_ptr = (struct Chord*) pgm_read_word (&list_of_chords[i]);
        memcpy_P(&chord_storage, chord_ptr, sizeof(struct Chord));
        chord = &chord_storage;
        
        if (*chord->state == IN_ONE_SHOT) {
            *chord->state = RESTART;
            chord->function(chord);
            if (*chord->state == RESTART) {
                *chord->state = IDLE;
            }
        }
    }
}

void process_finished_dances(void) {
    struct Chord chord_storage;
    struct Chord* chord_ptr;
    struct Chord* chord;
    
    for (int i = 0; i < NUMBER_OF_CHORDS; i++) {
        chord_ptr = (struct Chord*) pgm_read_word (&list_of_chords[i]);
        memcpy_P(&chord_storage, chord_ptr, sizeof(struct Chord));
        chord = &chord_storage;
        
        if (*chord->state == ACTIVATED) {
            *chord->state = PRESS_FROM_ACTIVE;
            chord->function(chord);
            if (a_key_went_through) {
                kill_one_shots();
            }
            dance_timer = timer_read();
        } else if (*chord->state == IDLE_IN_DANCE) {
            *chord->state = FINISHED;
            chord->function(chord);
            if (*chord->state == FINISHED) {
                *chord->state = RESTART;
                if (*chord->state == RESTART) {
                    *chord->state = IDLE;
                }
            }
        } else if (*chord->state == PRESS_FROM_ACTIVE) {
            *chord->state = FINISHED_FROM_ACTIVE;
            chord->function(chord);
            if (a_key_went_through) {
                kill_one_shots();
            }
            dance_timer = timer_read();
        }
    }
}

uint8_t keycodes_buffer_array_min(uint8_t* first_keycode_index) {
    for (int i = 0; i < NUMBER_OF_KEYS; i++) {
        if (keycodes_buffer_array[i] == 1) {
            if (first_keycode_index != NULL) {
                *first_keycode_index = (uint8_t) i;
            }
            return 1;
        }
    }
    return 0;
}

void remove_subchords(void) {
    struct Chord chord_storage;
    struct Chord* chord_ptr;
    struct Chord* chord;
    
    for (int i = 0; i < NUMBER_OF_CHORDS; i++) {
        chord_ptr = (struct Chord*) pgm_read_word (&list_of_chords[i]);
        memcpy_P(&chord_storage, chord_ptr, sizeof(struct Chord));
        chord = &chord_storage;
        
        if (!(*chord->state == READY || *chord->state == READY_IN_DANCE || *chord->state == READY_LOCKED)) {
            continue;
        }
        
        struct Chord chord_storage_2;
        struct Chord* chord_ptr_2;
        struct Chord* chord_2;
        for (int j = 0; j < NUMBER_OF_CHORDS; j++) {
            if (i == j) {continue;}
            
            chord_ptr_2 = (struct Chord*) pgm_read_word (&list_of_chords[j]);
            memcpy_P(&chord_storage_2, chord_ptr_2, sizeof(struct Chord));
            chord_2 = &chord_storage_2;
            
            if (are_hashed_keycodes_in_sound(chord_2->keycodes_hash, chord->keycodes_hash)) {
                if (*chord_2->state == READY) {
                    *chord_2->state = IDLE;
                }
                if (*chord_2->state == READY_IN_DANCE) {
                    *chord_2->state = IDLE_IN_DANCE;
                }
                if (*chord_2->state == READY_LOCKED) {
                    *chord_2->state = LOCKED;
                }
            }
        }
    }
}

void process_ready_chords(void) {
    uint8_t first_keycode_index = 0;
    while (keycodes_buffer_array_min(&first_keycode_index)) {
        // find ready chords
        struct Chord chord_storage;
        struct Chord* chord_ptr;
        struct Chord* chord;
        
        for (int i = 0; i < NUMBER_OF_CHORDS; i++) {
            chord_ptr = (struct Chord*) pgm_read_word (&list_of_chords[i]);
            memcpy_P(&chord_storage, chord_ptr, sizeof(struct Chord));
            chord = &chord_storage;
            
            // if the chord does not contain the first keycode
            bool contains_first_keycode = ((uint32_t) 1 << first_keycode_index) & chord->keycodes_hash;
            if (!contains_first_keycode) {
                continue;
            }
            
            if (!are_hashed_keycodes_in_array(chord->keycodes_hash)){
                continue;
            }
            
            if (*chord->state == LOCKED) {
                *chord->state = READY_LOCKED;
                continue;
            }
            
            if (!(chord->pseudolayer == current_pseudolayer || chord->pseudolayer == ALWAYS_ON)) {
                continue;
            }
            
            if (*chord->state == IDLE) {
                *chord->state = READY;
                continue;
            }
            
            if (*chord->state == IDLE_IN_DANCE) {
                *chord->state = READY_IN_DANCE;
            }
        }
        
        // remove subchords
        remove_subchords();
        
        // execute logic
        // this should be only one chord
        for (int i = 0; i < NUMBER_OF_CHORDS; i++) {
            chord_ptr = (struct Chord*) pgm_read_word (&list_of_chords[i]);
            memcpy_P(&chord_storage, chord_ptr, sizeof(struct Chord));
            chord = &chord_storage;
            
            if (*chord->state == READY_LOCKED) {
                *chord->state = RESTART;
                chord->function(chord);
                if (*chord->state == RESTART) {
                    *chord->state = IDLE;
                }
                break;
            }
            
            if (*chord->state == READY || *chord->state == READY_IN_DANCE) {
                if (last_chord && last_chord != chord) {
                    process_finished_dances();
                }
                
                bool lock_next_prev_state = lock_next;
                
                *chord->state = ACTIVATED;
                chord->function(chord);
                dance_timer = timer_read();
                
                if (lock_next && lock_next == lock_next_prev_state) {
                    lock_next = false;
                    *chord->state = PRESS_FROM_ACTIVE;
                    chord->function(chord);
                    if (*chord->state == PRESS_FROM_ACTIVE) {
                        *chord->state = LOCKED;
                    }
                    if (a_key_went_through) {
                        kill_one_shots();
                    }
                }
                break;
            }
        }
        
        // silence notes
        silence_keycode_hash_array(chord->keycodes_hash);
    }
}

void deactivate_active_chords(uint16_t keycode) {
    HASH_TYPE hash = (HASH_TYPE)1 << (keycode - SAFE_RANGE);
    bool broken;
    struct Chord chord_storage;
    struct Chord* chord_ptr;
    struct Chord* chord;
    
    for (int i = 0; i < NUMBER_OF_CHORDS; i++) {
        chord_ptr = (struct Chord*) pgm_read_word (&list_of_chords[i]);
        memcpy_P(&chord_storage, chord_ptr, sizeof(struct Chord));
        chord = &chord_storage;
        
        broken = are_hashed_keycodes_in_sound(hash, chord->keycodes_hash);
        if (!broken) {
            continue;
        }
        
        switch (*chord->state) {
            case ACTIVATED:
                *chord->state = DEACTIVATED;
                chord->function(chord);
                
                if (*chord->state == DEACTIVATED) {
                    dance_timer = timer_read();
                    *chord->state = IDLE_IN_DANCE;
                }
                if (*chord->state != IN_ONE_SHOT) {
                    kill_one_shots();
                }
                break;
            case PRESS_FROM_ACTIVE:
            case FINISHED_FROM_ACTIVE:
                *chord->state = RESTART;
                chord->function(chord);
                if (*chord->state == RESTART) {
                    *chord->state = IDLE;
                }
                kill_one_shots();
                break;
            default:
                break;
        }
    }
    
}

void process_command(void) {
    command_mode = 0;
    for (int i = 0; i < COMMAND_MAX_LENGTH; i++) {
        if (command_buffer[i]) {
            register_code(command_buffer[i]);
        }
        send_keyboard_report();
    }
    wait_ms(TAP_TIMEOUT);
    for (int i = 0; i < COMMAND_MAX_LENGTH; i++) {
        if (command_buffer[i]) {
            unregister_code(command_buffer[i]);
        }
        send_keyboard_report();
    }
    for (int i = 0; i < COMMAND_MAX_LENGTH; i++) {
        command_buffer[i] = 0;
    }
    command_ind = 0;
}

void process_leader(void) {
    in_leader_mode = false;
    for (int i = 0; i < NUMBER_OF_LEADER_COMBOS; i++) {
        uint16_t trigger[LEADER_MAX_LENGTH];
        memcpy_P(trigger, leader_triggers[i], LEADER_MAX_LENGTH * sizeof(uint16_t));
        
        if (identical(leader_buffer, trigger)) {
            (*leader_functions[i])();
            break;
        }
    }
    for (int i = 0; i < LEADER_MAX_LENGTH; i++) {
        leader_buffer[i] = 0;
    }
}

bool process_record_user(uint16_t keycode, keyrecord_t *record) {
    if (keycode < FIRST_INTERNAL_KEYCODE || keycode > LAST_INTERNAL_KEYCODE) {
        return true;
    }
    
    if (record->event.pressed) {
        sound_keycode_array(keycode);
    } else {
        process_ready_chords();
        deactivate_active_chords(keycode);
    }
    chord_timer = timer_read();
    leader_timer = timer_read();
    
    return false;
}

void matrix_scan_user(void) {
    bool chord_timer_expired = timer_elapsed(chord_timer) > CHORD_TIMEOUT;
    if (chord_timer_expired && keycodes_buffer_array_min(NULL)) {
        process_ready_chords();
    }
    
    bool dance_timer_expired = timer_elapsed(dance_timer) > DANCE_TIMEOUT;
    if (dance_timer_expired) { // would love to have && in_dance but not sure how
        process_finished_dances();
    }
    
    bool in_command_mode = command_mode == 2;
    if (in_command_mode) {
        process_command();
    }
    
    bool leader_timer_expired = timer_elapsed(leader_timer) > LEADER_TIMEOUT;
    if (leader_timer_expired && in_leader_mode) {
        process_leader();
    }
    
}

void clear(const struct Chord* self) {
    if (*self->state == ACTIVATED) {
        // kill all chords
        struct Chord chord_storage;
        struct Chord* chord_ptr;
        struct Chord* chord;
        
        for (int i = 0; i < NUMBER_OF_CHORDS; i++) {
            chord_ptr = (struct Chord*) pgm_read_word (&list_of_chords[i]);
            memcpy_P(&chord_storage, chord_ptr, sizeof(struct Chord));
            chord = &chord_storage;
            
            *chord->state = IDLE;
            
            if (chord->counter) {
                *chord->counter = 0;
            }
        }
        
        // clear keyboard
        clear_keyboard();
        send_keyboard_report();
        
        // switch to default pseudolayer
        current_pseudolayer = DEFAULT_PSEUDOLAYER;
        
        // clear all keyboard states
        lock_next = false;
        autoshift_mode = true;
        command_mode = 0;
        in_leader_mode = false;
        leader_ind = 0;
        dynamic_macro_mode = false;
        a_key_went_through = false;
        
        for (int i = 0; i < DYNAMIC_MACRO_MAX_LENGTH; i++) {
            dynamic_macro_buffer[i] = 0;
        }
    }
}