/*
  xsns_01_counter.ino - Counter sensors (water meters, electricity meters etc.) sensor support for Tasmota

  Copyright (C) 2020  Maarten Damen and Theo Arends

  This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifdef USE_COUNTER
/*********************************************************************************************\
 * Counter sensors (water meters, electricity meters etc.)
\*********************************************************************************************/

#define XSNS_01             1

#define D_PRFX_COUNTER "Counter"
#define D_CMND_COUNTERTYPE "Type"
#define D_CMND_COUNTERDEBOUNCE "Debounce"
#define D_CMND_COUNTERDEBOUNCELOW "DebounceLow"
#define D_CMND_COUNTERDEBOUNCEHIGH "DebounceHigh"

const char kCounterCommands[] PROGMEM = D_PRFX_COUNTER "|"  // Prefix
  "|" D_CMND_COUNTERTYPE "|" D_CMND_COUNTERDEBOUNCE  "|" D_CMND_COUNTERDEBOUNCELOW "|" D_CMND_COUNTERDEBOUNCEHIGH ;

void (* const CounterCommand[])(void) PROGMEM = {
  &CmndCounter, &CmndCounterType, &CmndCounterDebounce, &CmndCounterDebounceLow, &CmndCounterDebounceHigh };

uint8_t ctr_index[MAX_COUNTERS] =  { 0, 1, 2, 3 };

struct COUNTER {
  uint32_t timer[MAX_COUNTERS];  // Last counter time in micro seconds
  uint32_t timer_low_high[MAX_COUNTERS];  // Last low/high counter time in micro seconds
  uint8_t no_pullup = 0;         // Counter input pullup flag (1 = No pullup)
  uint8_t pin_state = 0;         // LSB0..3 Last state of counter pin; LSB7==0 IRQ is FALLING, LSB7==1 IRQ is CHANGE
  bool any_counter = false;
} Counter;

uint32_t last_cycle;
uint32_t cycle_time;

void ICACHE_RAM_ATTR CounterIsrArg(void *arg) {
  uint32_t index = *static_cast<uint8_t*>(arg);

  uint32_t time = micros();
  uint32_t debounce_time;

  if (Counter.pin_state) {
    // handle low and high debounce times when configured
    if (digitalRead(Pin(GPIO_CNTR1, index)) == bitRead(Counter.pin_state, index)) {
      // new pin state to be ignored because debounce time was not met during last IRQ
      return;
    }
    debounce_time = time - Counter.timer_low_high[index];
    if bitRead(Counter.pin_state, index) {
      // last valid pin state was high, current pin state is low
      if (debounce_time <= Settings.pulse_counter_debounce_high * 1000) return;
    } else {
      // last valid pin state was low, current pin state is high
      if (debounce_time <= Settings.pulse_counter_debounce_low * 1000) return;
    }
    // passed debounce check, save pin state and timing
    Counter.timer_low_high[index] = time;
    Counter.pin_state ^= (1<<index);
    // do not count on rising edge
    if bitRead(Counter.pin_state, index) {
      // PWMfrequency 100
      // restart PWM each second (german 50Hz has to up to 0.01% deviation)
      // Zero-HIGH is typical 2ms
      if (RtcSettings.pulse_counter[index]%100 == 0 && PinUsed(GPIO_PWM1, index) && Settings.flag4.zerocross_dimmer) {
        const uint32_t current_cycle = ESP.getCycleCount();
        // stop pwm on PIN to start in Sync with rising edge
        // calculate timeoffset to fire PWM
        uint16_t cur_col = Light.fade_start_10[0 + Light.pwm_offset];
        uint32_t dimm_time= 1000000 / Settings.pwm_frequency * (1024 - cur_col) / 1024;
        digitalWrite(Pin(GPIO_PWM1, index), LOW);
        // 1000µs to ensure not to fire on the next sinus wave
        if (dimm_time < (1000000 / Settings.pwm_frequency)-1000) {
          delayMicroseconds(dimm_time);
          // fire small PWM signal to start TRIAC/SSR. Kill on next
          // zero phase automatic.
          // calculate actual cycle time and adapt frequency im milli Hz steps
          // add 100.000 cpu ticks to ensure right step calculation
          uint32_t steps = (current_cycle-last_cycle+100000)/(clockCyclesPerMicrosecond() * 10000);
          cycle_time = (current_cycle-last_cycle)/steps;
#ifdef ESP8266
            pinMode(Pin(GPIO_PWM1, index), OUTPUT);
            uint32_t high = (cycle_time * 5) / 1023;
            uint32_t low = cycle_time - high;
            // Find the first GPIO being generated by checking GCC's find-first-set (returns 1 + the bit of the first 1 in an int32_t
            startWaveformClockCycles(Pin(GPIO_PWM1, index), high, low, 0, -1, 0, true);
#else  // ESP32
            analogWrite(Pin(GPIO_PWM1, index), 5);
#endif  // ESP8266 - ESP32
        }
        last_cycle = current_cycle;
      }
      return;
    }
  }

  debounce_time = time - Counter.timer[index];
  if (debounce_time > Settings.pulse_counter_debounce * 1000) {
    Counter.timer[index] = time;
    if (bitRead(Settings.pulse_counter_type, index)) {
      RtcSettings.pulse_counter[index] = debounce_time;
    } else {
      RtcSettings.pulse_counter[index]++;
    }
  }
}

/********************************************************************************************/

void CounterInterruptDisable(bool state) {
  if (state) {   // Disable interrupts
    if (Counter.any_counter) {
      for (uint32_t i = 0; i < MAX_COUNTERS; i++) {
        if (PinUsed(GPIO_CNTR1, i)) {
          detachInterrupt(Pin(GPIO_CNTR1, i));
        }
      }
      Counter.any_counter = false;
    }
  } else {       // Enable interrupts
    if (!Counter.any_counter) {
      CounterInit();
    }
  }
}

bool CounterPinState(void)
{
  if ((XdrvMailbox.index >= AGPIO(GPIO_CNTR1_NP)) && (XdrvMailbox.index < (AGPIO(GPIO_CNTR1_NP) + MAX_COUNTERS))) {
    bitSet(Counter.no_pullup, XdrvMailbox.index - AGPIO(GPIO_CNTR1_NP));
    XdrvMailbox.index -= (AGPIO(GPIO_CNTR1_NP) - AGPIO(GPIO_CNTR1));
    return true;
  }
  return false;
}

void CounterInit(void)
{
  for (uint32_t i = 0; i < MAX_COUNTERS; i++) {
    if (PinUsed(GPIO_CNTR1, i)) {
      Counter.any_counter = true;
      pinMode(Pin(GPIO_CNTR1, i), bitRead(Counter.no_pullup, i) ? INPUT : INPUT_PULLUP);
      if ((0 == Settings.pulse_counter_debounce_low) && (0 == Settings.pulse_counter_debounce_high) && !Settings.flag4.zerocross_dimmer) {
        Counter.pin_state = 0;
        attachInterruptArg(Pin(GPIO_CNTR1, i), CounterIsrArg, &ctr_index[i], FALLING);
      } else {
        Counter.pin_state = 0x8f;
        attachInterruptArg(Pin(GPIO_CNTR1, i), CounterIsrArg, &ctr_index[i], CHANGE);
      }
    }
  }
}

void CounterEverySecond(void)
{
  for (uint32_t i = 0; i < MAX_COUNTERS; i++) {
    if (PinUsed(GPIO_CNTR1, i)) {
      if (bitRead(Settings.pulse_counter_type, i)) {
        uint32_t time = micros() - Counter.timer[i];
        if (time > 4200000000) {  // 70 minutes
          RtcSettings.pulse_counter[i] = 4200000000;  // Set Timer to max in case of no more interrupts due to stall of measured device
        }
      }
    }
  }
}

void CounterSaveState(void)
{
  for (uint32_t i = 0; i < MAX_COUNTERS; i++) {
    if (PinUsed(GPIO_CNTR1, i)) {
      Settings.pulse_counter[i] = RtcSettings.pulse_counter[i];
    }
  }
}

void CounterShow(bool json)
{
  bool header = false;
  uint8_t dsxflg = 0;
  for (uint32_t i = 0; i < MAX_COUNTERS; i++) {
    if (PinUsed(GPIO_CNTR1, i)) {
      char counter[33];
      if (bitRead(Settings.pulse_counter_type, i)) {
        dtostrfd((double)RtcSettings.pulse_counter[i] / 1000000, 6, counter);
      } else {
        dsxflg++;
        snprintf_P(counter, sizeof(counter), PSTR("%lu"), RtcSettings.pulse_counter[i]);
      }

      if (json) {
        if (!header) {
          ResponseAppend_P(PSTR(",\"COUNTER\":{"));
        }
        ResponseAppend_P(PSTR("%s\"C%d\":%s"), (header)?",":"", i +1, counter);
        header = true;
#ifdef USE_DOMOTICZ
        if ((0 == tele_period) && (1 == dsxflg)) {
          DomoticzSensor(DZ_COUNT, RtcSettings.pulse_counter[i]);
          dsxflg++;
        }
#endif  // USE_DOMOTICZ
        if ((0 == tele_period ) && (Settings.flag3.counter_reset_on_tele)) {
          RtcSettings.pulse_counter[i] = 0;
        }
#ifdef USE_WEBSERVER
      } else {
        WSContentSend_PD(PSTR("{s}" D_COUNTER "%d{m}%s%s{e}"),
          i +1, counter, (bitRead(Settings.pulse_counter_type, i)) ? " " D_UNIT_SECOND : "");
#endif  // USE_WEBSERVER
      }
    }
  }
  if (header) {
    ResponseJsonEnd();
  }
}

/*********************************************************************************************\
 * Commands
\*********************************************************************************************/

void CmndCounter(void)
{
  if ((XdrvMailbox.index > 0) && (XdrvMailbox.index <= MAX_COUNTERS)) {
    if ((XdrvMailbox.data_len > 0) && PinUsed(GPIO_CNTR1, XdrvMailbox.index -1)) {
      if ((XdrvMailbox.data[0] == '-') || (XdrvMailbox.data[0] == '+')) {
        RtcSettings.pulse_counter[XdrvMailbox.index -1] += XdrvMailbox.payload;
        Settings.pulse_counter[XdrvMailbox.index -1] += XdrvMailbox.payload;
      } else {
        RtcSettings.pulse_counter[XdrvMailbox.index -1] = XdrvMailbox.payload;
        Settings.pulse_counter[XdrvMailbox.index -1] = XdrvMailbox.payload;
      }
    }
    ResponseCmndIdxNumber(RtcSettings.pulse_counter[XdrvMailbox.index -1]);
  }
}

void CmndCounterType(void)
{
  if ((XdrvMailbox.index > 0) && (XdrvMailbox.index <= MAX_COUNTERS)) {
    if ((XdrvMailbox.payload >= 0) && (XdrvMailbox.payload <= 1) && PinUsed(GPIO_CNTR1, XdrvMailbox.index -1)) {
      bitWrite(Settings.pulse_counter_type, XdrvMailbox.index -1, XdrvMailbox.payload &1);
      RtcSettings.pulse_counter[XdrvMailbox.index -1] = 0;
      Settings.pulse_counter[XdrvMailbox.index -1] = 0;
    }
    ResponseCmndIdxNumber(bitRead(Settings.pulse_counter_type, XdrvMailbox.index -1));
  }
}

void CmndCounterDebounce(void)
{
  if ((XdrvMailbox.payload >= 0) && (XdrvMailbox.payload < 32001)) {
    Settings.pulse_counter_debounce = XdrvMailbox.payload;
  }
  ResponseCmndNumber(Settings.pulse_counter_debounce);
}

void CmndCounterDebounceLow(void)
{
  if ((XdrvMailbox.payload >= 0) && (XdrvMailbox.payload < 32001)) {
    Settings.pulse_counter_debounce_low = XdrvMailbox.payload;
    CounterInit();
  }
  ResponseCmndNumber(Settings.pulse_counter_debounce_low);
}

void CmndCounterDebounceHigh(void)
{
  if ((XdrvMailbox.payload >= 0) && (XdrvMailbox.payload < 32001)) {
    Settings.pulse_counter_debounce_high = XdrvMailbox.payload;
    CounterInit();
  }
  ResponseCmndNumber(Settings.pulse_counter_debounce_high);
}

/*********************************************************************************************\
 * Interface
\*********************************************************************************************/

bool Xsns01(uint8_t function)
{
  bool result = false;

  if (Counter.any_counter) {
    switch (function) {
      case FUNC_EVERY_SECOND:
        CounterEverySecond();
        break;
      case FUNC_JSON_APPEND:
        CounterShow(1);
        break;
#ifdef USE_WEBSERVER
      case FUNC_WEB_SENSOR:
        CounterShow(0);
        break;
#endif  // USE_WEBSERVER
      case FUNC_SAVE_BEFORE_RESTART:
      case FUNC_SAVE_AT_MIDNIGHT:
        CounterSaveState();
        break;
      case FUNC_COMMAND:
        result = DecodeCommand(kCounterCommands, CounterCommand);
        break;
    }
  } else {
    switch (function) {
      case FUNC_INIT:
        CounterInit();
        break;
      case FUNC_PIN_STATE:
        result = CounterPinState();
        break;
    }
  }
  return result;
}

#endif  // USE_COUNTER