qmk_firmware/keyboards/gboards/engine/engine.c

/*  This is a stripped down version of the Georgi engine meant for use with
 *  Ginni. As such serial-Steno features are disabled, chords are 16bits and
 *  crap is removed where possible
 *
 *  Do not use this on anything other then Ginny if you want to be sane
 */
#include "engine.h"

// Chord state
C_SIZE cChord     = 0;  // Current Chord
int    chordIndex = 0;  // Keys in previousachord
C_SIZE pressed    = 0;  // number of held keys
C_SIZE chordState[32];  // Full Chord history
#define QWERBUF 24      // Size of chords to buffer for output

bool   repeatFlag  = false;  // Should we repeat?
C_SIZE pChord      = 0;      // Previous Chord
C_SIZE stickyBits  = 0;      // Or'd with every incoming press
int    pChordIndex = 0;      // Keys in previousachord
C_SIZE pChordState[32];      // Previous chord sate

// Key Dicts
extern const struct keyEntry     keyDict[];
extern const struct comboEntry   cmbDict[];
extern const struct funcEntry    funDict[];
extern const struct stringEntry  strDict[];
extern const struct specialEntry spcDict[];
extern size_t                    specialLen;
extern size_t                    stringLen;
extern size_t                    funcsLen;
extern size_t                    keyLen;
extern size_t                    comboLen;

// Mode state
enum MODE { STENO = 0, QWERTY, COMMAND };
enum MODE pMode;
enum MODE cMode = QWERTY;

// Command State
#define MAX_CMD_BUF 20
uint8_t CMDLEN = 0;
uint8_t CMDBUF[MAX_CMD_BUF];

// Key Repeat state
bool     inChord    = false;
bool     repEngaged = false;
uint16_t repTimer   = 0;
#define REP_INIT_DELAY 750
#define REP_DELAY 25

// Mousekeys state
bool   inMouse = false;
int8_t mousePress;

// All processing done at chordUp goes through here
void processKeysUp() {
    // Check for mousekeys, this is release
#ifdef MOUSEKEY_ENABLE
    if (inMouse) {
        inMouse = false;
        mousekey_off(mousePress);
        mousekey_send();
    }
#endif

    // handle command mode
    if (cChord == COMMAND_MODE) {
#ifndef NO_DEBUG
        uprintf("COMMAND Toggle\n");
#endif
        if (cMode != COMMAND) {  // Entering Command Mode
            CMDLEN = 0;
            pMode  = cMode;
            cMode  = COMMAND;
        } else {  // Exiting Command Mode
            cMode = pMode;

            // Press all and release all
            for (int i = 0; i < CMDLEN; i++) {
                register_code(CMDBUF[i]);
            }
            clear_keyboard();
        }
    }

    // Process and reset state
    processChord();
    cChord     = pressed;
    inChord    = false;
    chordIndex = 0;
    clear_keyboard();
    repEngaged = false;
    for (int i = 0; i < 32; i++) chordState[i] = 0xFFFF;
}

// Update Chord State
bool process_record_kb(uint16_t keycode, keyrecord_t *record) {
    // Everything happens in here when steno keys come in.
    // Bail on keyup

    // Update key repeat timers
    repTimer = timer_read();
    bool pr  = record->event.pressed;
    // Switch on the press adding to chord
    switch (keycode) {
        ENGINE_CONFIG
        default:
            return true;
    }

    // Handle any postprocessing

    // All keys up, send it!
    if (inChord && !pr && (pressed & IN_CHORD_MASK) == 0) {
        processKeysUp();
        return false;
    }
    if (pressed == 0 && !pr) {
        processKeysUp();
        return false;
    }

    cChord |= pressed;
    cChord  = process_engine_post(cChord, keycode, record);
    inChord = (cChord & IN_CHORD_MASK) != 0;

    // Store previous state for fastQWER
    if (pr) {
        chordState[chordIndex] = cChord;
        chordIndex++;
    }

#ifndef NO_DEBUG
    uprintf("Chord: %u\n", cChord);
#endif
    return false;
}
void matrix_scan_user(void) {
    // We abuse this for early sending of key
    // Key repeat only on QWER/SYMB layers
    if (cMode != QWERTY || !inChord) return;

        // Check timers
#ifndef NO_HOLD
    if (!repEngaged && timer_elapsed(repTimer) > REP_INIT_DELAY) {
        // Process Key for report
        processChord();

        // Send report to host
        send_keyboard_report();
        repEngaged = true;
    }
#endif
};

// Try and match cChord
C_SIZE mapKeys(C_SIZE chord, bool lookup) {
    lookup = lookup || repEngaged;
#ifndef NO_DEBUG
    if (!lookup) uprint("SENT!\n");
#endif
    // Single key chords
    for (int i = 0; i < keyLen; i++) {
        if (keyDict[i].chord == chord) {
            if (!lookup) SEND(keyDict[i].key);
            return chord;
        }
    }

    // strings
    for (int i = 0; i < stringLen; i++) {
        struct stringEntry fromPgm;
        memcpy_P(&fromPgm, &strDict[i], sizeof(stringEntry_t));
        if (fromPgm.chord == chord) {
            if (!lookup) {
                if (get_mods() & (MOD_LSFT | MOD_RSFT)) {
                    set_mods(get_mods() & ~(MOD_LSFT | MOD_RSFT));
                    set_oneshot_mods(MOD_LSFT);
                }
                send_string_P((PGM_P)(fromPgm.str));
            }
            return chord;
        }
    }

    // combos
    for (int i = 0; i < comboLen; i++) {
        struct comboEntry fromPgm;
        memcpy_P(&fromPgm, &cmbDict[i], sizeof(comboEntry_t));
        if (fromPgm.chord == chord) {
#ifndef NO_DEBUG
            uprintf("%d found combo\n", i);
#endif

            if (!lookup) {
                uint8_t comboKeys[COMBO_MAX];
                memcpy_P(&comboKeys, fromPgm.keys, sizeof(uint8_t) * COMBO_MAX);
                for (int j = 0; j < COMBO_MAX; j++)
#ifndef NO_DEBUG
                    uprintf("Combo [%u]: %u\n", j, comboKeys[j]);
#endif

                for (int j = 0; (j < COMBO_MAX) && (comboKeys[j] != COMBO_END); j++) {
#ifndef NO_DEBUG
                    uprintf("Combo [%u]: %u\n", j, comboKeys[j]);
#endif
                    SEND(comboKeys[j]);
                }
            }
            return chord;
        }
    }

    // functions
    for (int i = 0; i < funcsLen; i++) {
        if (funDict[i].chord == chord) {
            if (!lookup) funDict[i].act();
            return chord;
        }
    }

    // Special handling
    for (int i = 0; i < specialLen; i++) {
        if (spcDict[i].chord == chord) {
            if (!lookup) {
                uint16_t arg = spcDict[i].arg;
                switch (spcDict[i].action) {
                    case SPEC_STICKY:
                        SET_STICKY(arg);
                        break;
                    case SPEC_REPEAT:
                        REPEAT();
                        break;
                    case SPEC_CLICK:
                        CLICK_MOUSE((uint8_t)arg);
                        break;
                    case SPEC_SWITCH:
                        SWITCH_LAYER(arg);
                        break;
                    default:
                        SEND_STRING("Invalid Special in Keymap");
                }
            }
            return chord;
        }
    }

    if ((chord & IN_CHORD_MASK) && (chord & IN_CHORD_MASK) != chord && mapKeys((chord & IN_CHORD_MASK), true) == (chord & IN_CHORD_MASK)) {
#ifndef NO_DEBUG
        uprintf("Try with ignore mask:%u\n", (chord & IN_CHORD_MASK));
#endif
        mapKeys((chord & ~IN_CHORD_MASK), lookup);
        mapKeys((chord & IN_CHORD_MASK), lookup);
        return chord;
    }
#ifndef NO_DEBUG
    uprintf("Reached end\n");
#endif
    return 0;
}
// Traverse the chord history to a given point
// Returns the mask to use
void processChord(void) {
    // Save the clean chord state
    C_SIZE savedChord = cChord;

    // Apply Stick Bits if needed
    if (stickyBits != 0) {
        cChord |= stickyBits;
        for (int i = 0; i <= chordIndex; i++) chordState[i] |= stickyBits;
    }

    // First we test if a whole chord was passsed
    // If so we just run it handling repeat logic
    if (mapKeys(cChord, true) == cChord) {
        mapKeys(cChord, false);
        // Repeat logic
        if (repeatFlag) {
#ifndef NO_DEBUG
            uprintf("repeating?\n");
#endif
            restoreState();
            repeatFlag = false;
            processChord();
        } else {
            saveState(cChord);
        }
        return;
    }

    C_SIZE next = process_chord_getnext(cChord);
    if (next && next != cChord) {
#ifndef NO_DEBUG
        uprintf("Trying next candidate: %u\n", next);
#endif
        if (mapKeys(next, true) == next) {
            mapKeys(next, false);
            // Repeat logic
            if (repeatFlag) {
#ifndef NO_DEBUG
                uprintf("repeating?\n");
#endif
                restoreState();
                repeatFlag = false;
                processChord();
            } else {
                saveState(cChord);
            }
            return;
        }
    }

#ifndef NO_DEBUG
    uprintf("made it past the maw\n");
#endif

    // Iterate through chord picking out the individual
    // and longest chords
    C_SIZE bufChords[QWERBUF];
    int    bufLen = 0;
    C_SIZE mask   = 0;

    // We iterate over it multiple times to catch the longest
    // chord. Then that gets addded to the mask and re run.
    while (savedChord != mask) {
        C_SIZE test         = 0;
        C_SIZE longestChord = 0;

        for (int i = 0; i <= chordIndex; i++) {
            cChord = chordState[i] & ~mask;
            if (cChord == 0) continue;

            test = mapKeys(cChord, true);
            if (test != 0) {
                longestChord = test;
            }
        }

        mask |= longestChord;
        bufChords[bufLen] = longestChord;
        bufLen++;

        // That's a loop of sorts, halt processing
        if (bufLen >= QWERBUF) {
#ifndef NO_DEBUG
            uprintf("looped. exiting");
#endif
            return;
        }
    }

    // Now that the buffer is populated, we run it
    for (int i = 0; i < bufLen; i++) {
        cChord = bufChords[i];
#ifndef NO_DEBUG
        uprintf("sending: %u\n", cChord);
#endif
        mapKeys(cChord, false);
    }

    // Save state in case of repeat
    if (!repeatFlag) {
        saveState(savedChord);
    }

    // Restore cChord for held repeat
    cChord = savedChord;
    return;
}
void saveState(C_SIZE cleanChord) {
    pChord      = cleanChord;
    pChordIndex = chordIndex;
    for (int i = 0; i < 32; i++) pChordState[i] = chordState[i];
}
void restoreState() {
    cChord     = pChord;
    chordIndex = pChordIndex;
    for (int i = 0; i < 32; i++) chordState[i] = pChordState[i];
}

// Macros for calling from keymap.c
void SEND(uint8_t kc) {
    // Send Keycode, Does not work for Quantum Codes
    if (cMode == COMMAND && CMDLEN < MAX_CMD_BUF) {
#ifndef NO_DEBUG
        uprintf("CMD LEN: %d BUF: %d\n", CMDLEN, MAX_CMD_BUF);
#endif
        CMDBUF[CMDLEN] = kc;
        CMDLEN++;
    }

    if (cMode != COMMAND) register_code(kc);
    return;
}
void REPEAT(void) {
    if (cMode != QWERTY) return;

    repeatFlag = true;
    return;
}
void SET_STICKY(C_SIZE stick) {
    stickyBits ^= stick;
    return;
}
void CLICK_MOUSE(uint8_t kc) {
#ifdef MOUSEKEY_ENABLE
    mousekey_on(kc);
    mousekey_send();

    // Store state for later use
    inMouse    = true;
    mousePress = kc;
#endif
}
void SWITCH_LAYER(int layer) {
#ifndef NO_ACTION_LAYER
    if (keymapsCount >= layer) layer_on(layer);
#endif
}
uint8_t bitpop_v(C_SIZE val) {
#if C_SIZE == uint8_t
    return bitpop(val);
#elif C_SIZE == uint16_t
    return bitpop16(val);
#elif C_SIZE == uint32_t
    return bitpop32(val);
#elif C_SIZE == uint64_t
    uint8_t n = 0;
    if (bits >> 32) {
        bits >>= 32;
        n += 32;
    }
    if (bits >> 16) {
        bits >>= 16;
        n += 16;
    }
    if (bits >> 8) {
        bits >>= 8;
        n += 8;
    }
    if (bits >> 4) {
        bits >>= 4;
        n += 4;
    }
    if (bits >> 2) {
        bits >>= 2;
        n += 2;
    }
    if (bits >> 1) {
        bits >>= 1;
        n += 1;
    }
    return n;
#else
#    error unsupported C_SIZE
#endif
}
__attribute__((weak)) C_SIZE process_engine_post(C_SIZE cur_chord, uint16_t keycode, keyrecord_t *record) { return cur_chord; }