//#define DEBUGF LogTextMessage
#define DEBUGF(...)                                                            \
  {}

enum {
  CLOCK_SOURCE_internal = 0,
  CLOCK_SOURCE_external = 1,
  CLOCK_SOURCE_midi = 2,
  CLOCK_SOURCE_midi_omni = 3
} CLOCK_SOURCE;

int32_t start_sequence;
int32_t clock_source;
int32_t clock_multiplier;
int32_t clock_divider;
uint32_t sync_count; // At least N clocks before deriving synced time
uint32_t sync_time;  // Synced time expressed in fractional delay length
uint32_t ktimer;     // 3kHz timer
uint32_t last_ktime;
float delay_length_cpl; // cache result of  1.0 / lenght of delay line
uint32_t old_24ppq;

__attribute__((always_inline)) __STATIC_INLINE float Q27ToF(int32_t op1) {
  float fop1 = *(float *)(&op1);
  __ASM volatile("VCVT.F32.S32 %0, %0, 27" : "+w"(fop1));
  return (fop1);
}

__attribute__((always_inline)) __STATIC_INLINE int32_t FToQ27(float fop1) {
  __ASM volatile("VCVT.S32.F32 %0, %0, 27" : "+w"(fop1));
  int32_t r = *(int32_t *)(&fop1);
  return (r);
}

__attribute__((always_inline)) __STATIC_INLINE int
midi_device_test(midi_device_t dev, uint8_t port, int selected_dev,
                 uint8_t selected_port) {
  if ((selected_dev == MIDI_DEVICE_OMNI) ||
      (selected_dev == dev && selected_port == port))
    return 1;
  return 0;
}

#if attr_smooth > 0
#define FIFO_EXP attr_smooth
#define FIFO_LEN (1 << FIFO_EXP)
#define FIFO_MASK (FIFO_LEN - 1)
typedef struct _AveragerContext {
  int32_t fifo[FIFO_LEN];
  int32_t fifo_i;
  int32_t acc;
} AveragerContext;
AveragerContext avg;
__attribute__((always_inline)) __STATIC_INLINE int32_t
moving_average(AveragerContext *avg, int32_t new_value) {
  avg->fifo_i = (avg->fifo_i + 1) & FIFO_MASK;
  avg->acc -= avg->fifo[avg->fifo_i];
  avg->acc += new_value;
  avg->fifo[avg->fifo_i] = new_value;
  return avg->acc >> FIFO_EXP;
}
#endif

void on_clock(void) {
  float period;
  int32_t kperiod;
#if attr_smooth > 0
  kperiod = moving_average(&avg, ktimer - last_ktime);
#else
  kperiod = ktimer - last_ktime;
#endif
  last_ktime = ktimer;
  period = kperiod * 16 * clock_divider;
  period = period / clock_multiplier;

  if (period < 1.0f) {
    period = 1.0f;
  }

  if (sync_count < 1) {
    sync_count++;
  } else {
    sync_time = FToQ27(period * delay_length_cpl);
  }
}

#if attr_smooth > 0
for (avg.fifo_i = 0; avg.fifo_i < FIFO_LEN; avg.fifo_i++) {
  avg.fifo[avg.fifo_i] = 0;
}
avg.fifo_i = 0;
avg.acc = 0;
#endif
start_sequence = 0;
clock_source = CLOCK_SOURCE_internal;
clock_multiplier = 1;
clock_divider = 12;
sync_count = 0;
sync_time = 0;
ktimer = 0;
last_ktime = 0;
delay_length_cpl = 1.0f / attr_delayname.LENGTH;
old_24ppq = 0;

// Use preset time until synced
if (start_sequence == 0 && clock_source != CLOCK_SOURCE_internal) {
  sync_time = param_time;
  start_sequence++;
}

#ifdef USE_SYNC_HOLDOFF
// If too long between clocks (likely absence of clock), require two successive
// clocks to resync. Use max delay time as the minimum clock interval (using 5
// seconds for now)?
if (ktimer - last_ktime > (5 * 3000)) {
  sync_count = 0;
}
#endif

// Live overrides for the clock source and clock divider and multiplier
// parameters. Allow clock selection without restarting the patch is good :)
// (The int32 spinbox is not CC assignable...(bug?))
if (inlet_clkoverride > 0) {
  clock_source = inlet_clkoverride - 1;
  if (clock_source > CLOCK_SOURCE_midi_omni) {
    clock_source = CLOCK_SOURCE_midi_omni;
  } else if (clock_source < CLOCK_SOURCE_internal) {
    clock_source = CLOCK_SOURCE_internal;
  }
} else {
  clock_source = attr_clocksource;
}

if (inlet_divoverride > 0) {
  clock_divider = inlet_divoverride;
  if (clock_divider < 1) {
    clock_divider = 1;
  }
} else {
  clock_divider = param_clockdiv;
}

if (inlet_muloverride > 0) {
  clock_multiplier = inlet_muloverride;
  if (clock_multiplier < 1) {
    clock_multiplier = 1;
  }
} else {
  clock_multiplier = param_clockmul;
}

if (clock_source == CLOCK_SOURCE_external && inlet_24ppq && !old_24ppq) {
  on_clock();
}

int32_t tmp_time;
if (clock_source != CLOCK_SOURCE_internal) {
  tmp_time = sync_time;
} else {
  tmp_time = param_time;
}

// tmod is scaled to cover the delay range
int32_t time_mod = ___SMMUL((tmp_time + inlet_time) << 3, inlet_tmod << 2);
int32_t total_time = __USAT(tmp_time + inlet_time + time_mod, 27);
uint32_t length = total_time >> (27 - attr_delayname.LENGTHPOW);

if (length > attr_delayname.LENGTHMASK - BUFSIZE) {
  length = attr_delayname.LENGTHMASK - BUFSIZE;
}

uint32_t delay = attr_delayname.writepos - length - BUFSIZE;

outlet_time = total_time;
old_24ppq = inlet_24ppq;
ktimer++;

outlet_out = attr_delayname.array[(delay++) & attr_delayname.LENGTHMASK];

if (clock_source == CLOCK_SOURCE_midi_omni ||
    (clock_source == CLOCK_SOURCE_midi &&
     midi_device_test(dev, port, attr_device) == 1)) {
  if (status == MIDI_TIMING_CLOCK) {
    on_clock();
  }
}