/*
  support_switch.ino - switch support for Tasmota

  Copyright (C) 2021  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/>.
*/

#define SWITCH_V3
#ifdef SWITCH_V3
/*********************************************************************************************\
 * Switch support with input filter
 *
 * Inspired by (https://github.com/OLIMEX/olimex-iot-firmware-esp8266/blob/master/olimex/user/user_switch2.c)
\*********************************************************************************************/

const uint8_t SWITCH_PROBE_INTERVAL = 10;      // Time in milliseconds between switch input probe
const uint8_t SWITCH_FAST_PROBE_INTERVAL = 2;  // Time in milliseconds between switch input probe for AC detection
const uint8_t AC_PERIOD = (20 + SWITCH_FAST_PROBE_INTERVAL - 1) / SWITCH_FAST_PROBE_INTERVAL;   // Duration of an AC wave in probe intervals

// Switch Mode definietions
#define SM_TIMER_MASK         0x3F
#define SM_NO_TIMER_MASK      0xFF
#define SM_FIRST_PRESS        0x40
#define SM_SECOND_PRESS       0x80
#define POWER_NONE            99

const char kSwitchPressStates[] PROGMEM =
  "||||POWER_INCREMENT|POWER_INV|POWER_CLEAR|POWER_RELEASE|POWER_100|";

#include <Ticker.h>

Ticker TickerSwitch;

struct SWITCH {
  uint32_t debounce = 0;                     // Switch debounce timer
  uint16_t no_pullup_mask = 0;               // Switch pull-up bitmask flags
  uint8_t state[MAX_SWITCHES] = { 0 };
  uint8_t last_state[MAX_SWITCHES];          // Last wall switch states
  uint8_t hold_timer[MAX_SWITCHES] = { 0 };  // Timer for wallswitch push button hold
  uint8_t virtual_state[MAX_SWITCHES];       // Virtual switch states
  uint8_t first_change = 0;
  uint8_t present = 0;
} Switch;

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

void SwitchPullupFlag(uint32 switch_bit) {
  bitSet(Switch.no_pullup_mask, switch_bit);
}

void SwitchSetVirtual(uint32_t index, uint32_t state) {
  Switch.virtual_state[index] = state;
}

uint8_t SwitchGetVirtual(uint32_t index) {
  return Switch.virtual_state[index];
}

uint8_t SwitchLastState(uint32_t index) {
  return Switch.last_state[index];
}

bool SwitchState(uint32_t index) {
  uint32_t switchmode = Settings.switchmode[index];
  return ((FOLLOW_INV == switchmode) ||
          (PUSHBUTTON_INV == switchmode) ||
          (PUSHBUTTONHOLD_INV == switchmode) ||
          (FOLLOWMULTI_INV == switchmode) ||
          (PUSHHOLDMULTI_INV == switchmode) ||
          (PUSHON_INV == switchmode)
         ) ^ Switch.last_state[index];
}

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

void SwitchProbe(void) {
  if (TasmotaGlobal.uptime < 4) { return; }                  // Block GPIO for 4 seconds after poweron to workaround Wemos D1 / Obi RTS circuit

  uint32_t state_filter;
  uint32_t first_change = Switch.first_change;
  uint32_t debounce_flags = Settings.switch_debounce % 10;
  bool force_high = (debounce_flags &1);                     // 51, 101, 151 etc
  bool force_low = (debounce_flags &2);                      // 52, 102, 152 etc
  bool ac_detect = (debounce_flags == 9);

  if (ac_detect) {
    if (Settings.switch_debounce < 2 * AC_PERIOD * SWITCH_FAST_PROBE_INTERVAL + 9) {
      state_filter = 2 * AC_PERIOD;
    } else if (Settings.switch_debounce > (0x7f - 2 * AC_PERIOD) * SWITCH_FAST_PROBE_INTERVAL) {
      state_filter = 0x7f;
    } else {
      state_filter = (Settings.switch_debounce - 9) / SWITCH_FAST_PROBE_INTERVAL;
    }
  } else {
    state_filter = Settings.switch_debounce / SWITCH_PROBE_INTERVAL;	// 5, 10, 15
  }

  for (uint32_t i = 0; i < MAX_SWITCHES; i++) {
    if (!PinUsed(GPIO_SWT1, i)) { continue; }

    // Olimex user_switch2.c code to fix 50Hz induced pulses
    if (1 == digitalRead(Pin(GPIO_SWT1, i))) {

      if (ac_detect) {                                     // Enabled with SwitchDebounce x9
        Switch.state[i] |= 0x80;
        if (Switch.state[i] > 0x80) {
          Switch.state[i]--;
          if (0x80 == Switch.state[i]) {
            Switch.virtual_state[i] = 0;
            Switch.first_change = false;
          }
        }
      } else {

        if (force_high) {                                  // Enabled with SwitchDebounce x1
          if (1 == Switch.virtual_state[i]) {
            Switch.state[i] = state_filter;                // With noisy input keep current state 1 unless constant 0
          }
        }

        if (Switch.state[i] < state_filter) {
          Switch.state[i]++;
          if (state_filter == Switch.state[i]) {
            Switch.virtual_state[i] = 1;
          }
        }
      }
    } else {

      if (ac_detect) {                                     // Enabled with SwitchDebounce x9
        /*
          * Moes MS-104B and similar devices using an AC detection circuitry
          * on their switch inputs generating an ~4 ms long low pulse every
          * AC wave. We start the time measurement on the falling edge.
          *
          * state: bit7: previous state, bit6..0: counter
          */
        if (Switch.state[i] & 0x80) {
          Switch.state[i] &= 0x7f;
          if (Switch.state[i] < state_filter - 2 * AC_PERIOD) {
            Switch.state[i] += 2 * AC_PERIOD;
          } else {
            Switch.state[i] = state_filter;
            Switch.virtual_state[i] = 1;
            if (first_change) {
              Switch.last_state[i] = 1;
              Switch.first_change = false;
            }
          }
        } else {
          if (Switch.state[i] > 0x00) {
            Switch.state[i]--;
            if (0x00 == Switch.state[i]) {
              Switch.virtual_state[i] = 0;
              Switch.first_change = false;
            }
          }
        }
      } else {

        if (force_low) {                                   // Enabled with SwitchDebounce x2
          if (0 == Switch.virtual_state[i]) {
            Switch.state[i] = 0;                           // With noisy input keep current state 0 unless constant 1
          }
        }

        if (Switch.state[i] > 0) {
          Switch.state[i]--;
          if (0 == Switch.state[i]) {
            Switch.virtual_state[i] = 0;
          }
        }
      }
    }
  }
}

void SwitchInit(void) {
  bool ac_detect = (Settings.switch_debounce % 10 == 9);

  Switch.present = 0;
  for (uint32_t i = 0; i < MAX_SWITCHES; i++) {
    Switch.last_state[i] = 1;  // Init global to virtual switch state;
    if (PinUsed(GPIO_SWT1, i)) {
      Switch.present++;
#ifdef ESP8266
      pinMode(Pin(GPIO_SWT1, i), bitRead(Switch.no_pullup_mask, i) ? INPUT : ((16 == Pin(GPIO_SWT1, i)) ? INPUT_PULLDOWN_16 : INPUT_PULLUP));
#endif  // ESP8266
#ifdef ESP32
      pinMode(Pin(GPIO_SWT1, i), bitRead(Switch.no_pullup_mask, i) ? INPUT : INPUT_PULLUP);
#endif  // ESP32
      if (ac_detect) {
        Switch.state[i] = 0x80 + 2 * AC_PERIOD;
        Switch.last_state[i] = 0;				// Will set later in the debouncing code
      } else {
        Switch.last_state[i] = digitalRead(Pin(GPIO_SWT1, i));  // Set global now so doesn't change the saved power state on first switch check
      }
    }
    Switch.virtual_state[i] = Switch.last_state[i];
  }
  if (Switch.present) {
    Switch.first_change = true;
    TickerSwitch.attach_ms((ac_detect) ? SWITCH_FAST_PROBE_INTERVAL : SWITCH_PROBE_INTERVAL, SwitchProbe);
  }
}

/*********************************************************************************************\
 * Switch handler
\*********************************************************************************************/

void SwitchHandler(uint32_t mode) {
  if (TasmotaGlobal.uptime < 4) { return; }                  // Block GPIO for 4 seconds after poweron to workaround Wemos D1 / Obi RTS circuit

  uint32_t loops_per_second = 1000 / Settings.switch_debounce;

  for (uint32_t i = 0; i < MAX_SWITCHES; i++) {
    if (PinUsed(GPIO_SWT1, i) || (mode)) {
      uint32_t button = Switch.virtual_state[i];
      uint32_t switchflag = POWER_TOGGLE +1;
      uint32_t mqtt_action = POWER_NONE;

      if (Switch.hold_timer[i] & (((Settings.switchmode[i] == PUSHHOLDMULTI) | (Settings.switchmode[i] == PUSHHOLDMULTI_INV)) ? SM_TIMER_MASK: SM_NO_TIMER_MASK)) {
        Switch.hold_timer[i]--;
        if ((Switch.hold_timer[i] & SM_TIMER_MASK) == loops_per_second * Settings.param[P_HOLD_TIME] / 25) {
          if ((Settings.switchmode[i] == PUSHHOLDMULTI) & (NOT_PRESSED == Switch.last_state[i])) {
            SendKey(KEY_SWITCH, i +1, POWER_INCREMENT);      // Execute command via MQTT
          }
          if ((Settings.switchmode[i] == PUSHHOLDMULTI_INV) & (PRESSED == Switch.last_state[i])) {
            SendKey(KEY_SWITCH, i +1, POWER_INCREMENT);      // Execute command via MQTT
          }
        }
        if (0 == (Switch.hold_timer[i] & (((Settings.switchmode[i] == PUSHHOLDMULTI) | (Settings.switchmode[i] == PUSHHOLDMULTI_INV)) ? SM_TIMER_MASK: SM_NO_TIMER_MASK))) {
          switch (Settings.switchmode[i]) {
            case TOGGLEMULTI:
              switchflag = POWER_TOGGLE;                     // Toggle after hold
              break;
            case FOLLOWMULTI:
              switchflag = button &1;                        // Follow wall switch state after hold
              break;
            case FOLLOWMULTI_INV:
              switchflag = ~button &1;                       // Follow inverted wall switch state after hold
              break;
            case PUSHHOLDMULTI:
              if (NOT_PRESSED == button) {
                Switch.hold_timer[i] = loops_per_second * Settings.param[P_HOLD_TIME] / 25;
                SendKey(KEY_SWITCH, i +1, POWER_INCREMENT);  // Execute command via MQTT
                mqtt_action = POWER_INCREMENT;
              } else {
                Switch.hold_timer[i]= 0;
                SendKey(KEY_SWITCH, i +1, POWER_CLEAR);      // Execute command via MQTT
                mqtt_action = POWER_CLEAR;
              }
              break;
            case PUSHHOLDMULTI_INV:
              if (PRESSED == button) {
                Switch.hold_timer[i] = loops_per_second * Settings.param[P_HOLD_TIME] / 25;
                SendKey(KEY_SWITCH, i +1, POWER_INCREMENT);  // Execute command via MQTT
                mqtt_action = POWER_INCREMENT;

              } else {
                Switch.hold_timer[i]= 0;
                SendKey(KEY_SWITCH, i +1, POWER_CLEAR);      // Execute command via MQTT
                mqtt_action = POWER_CLEAR;
              }
              break;
          default:
            SendKey(KEY_SWITCH, i +1, POWER_HOLD);           // Execute command via MQTT
            mqtt_action = POWER_HOLD;
            break;
          }
        }
      }

      if (button != Switch.last_state[i]) {  // This implies if ((PRESSED == button) then (NOT_PRESSED == Switch.last_state[i]))
        switch (Settings.switchmode[i]) {
        case TOGGLE:
        case PUSHBUTTON_TOGGLE:
          switchflag = POWER_TOGGLE;         // Toggle
          break;
        case FOLLOW:
          switchflag = button &1;            // Follow wall switch state
          break;
        case FOLLOW_INV:
          switchflag = ~button &1;           // Follow inverted wall switch state
          break;
        case PUSHBUTTON:
          if (PRESSED == button) {
            switchflag = POWER_TOGGLE;       // Toggle with pushbutton to Gnd
          }
          break;
        case PUSHBUTTON_INV:
          if (NOT_PRESSED == button) {
            switchflag = POWER_TOGGLE;       // Toggle with releasing pushbutton from Gnd
          }
          break;
        case PUSHBUTTONHOLD:
          if (PRESSED == button) {
            Switch.hold_timer[i] = loops_per_second * Settings.param[P_HOLD_TIME] / 10;  // Start timer on button press
          }
          if ((NOT_PRESSED == button) && (Switch.hold_timer[i])) {
            Switch.hold_timer[i] = 0;        // Button released and hold timer not expired : stop timer...
            switchflag = POWER_TOGGLE;       // ...and Toggle
          }
          break;
        case PUSHBUTTONHOLD_INV:
          if (NOT_PRESSED == button) {
            Switch.hold_timer[i] = loops_per_second * Settings.param[P_HOLD_TIME] / 10;  // Start timer on button press...
          }
          if ((PRESSED == button) && (Switch.hold_timer[i])) {
            Switch.hold_timer[i] = 0;        // Button released and hold timer not expired : stop timer.
            switchflag = POWER_TOGGLE;       // ...and Toggle
          }
          break;
        case TOGGLEMULTI:
        case FOLLOWMULTI:
        case FOLLOWMULTI_INV:
          if (Switch.hold_timer[i]) {
            Switch.hold_timer[i] = 0;
            SendKey(KEY_SWITCH, i +1, POWER_HOLD);              // Execute command via MQTT
            mqtt_action = POWER_HOLD;
          } else {
            Switch.hold_timer[i] = loops_per_second / 2;        // 0.5 second multi press window
          }
          break;
        case PUSHHOLDMULTI:
          if (NOT_PRESSED == button) {
            if ((Switch.hold_timer[i] & SM_TIMER_MASK) != 0) {
              Switch.hold_timer[i] = ((Switch.hold_timer[i] & ~SM_TIMER_MASK) == SM_FIRST_PRESS) ? SM_SECOND_PRESS : 0;
              SendKey(KEY_SWITCH, i +1, POWER_INV);             // Execute command via MQTT
              mqtt_action = POWER_INV;
            }
          } else {
            if ((Switch.hold_timer[i] & SM_TIMER_MASK) > loops_per_second * Settings.param[P_HOLD_TIME] / 25) {
              if((Switch.hold_timer[i] & ~SM_TIMER_MASK) != SM_SECOND_PRESS) {
                Switch.hold_timer[i]= SM_FIRST_PRESS;
                switchflag = POWER_TOGGLE;                      // Toggle with pushbutton
              }
              else{
                SendKey(KEY_SWITCH, i +1, POWER_100);           // Execute command via MQTT
                mqtt_action = POWER_100;
                Switch.hold_timer[i]= 0;
              }
            } else {
              Switch.hold_timer[i]= 0;
              SendKey(KEY_SWITCH, i +1, POWER_RELEASE);         // Execute command via MQTT
              mqtt_action = POWER_RELEASE;
            }
          }
          Switch.hold_timer[i] = (Switch.hold_timer[i] & ~SM_TIMER_MASK) | loops_per_second * Settings.param[P_HOLD_TIME] / 10;
          break;
        case PUSHHOLDMULTI_INV:
          if (PRESSED == button) {
            if ((Switch.hold_timer[i] & SM_TIMER_MASK) != 0) {
              Switch.hold_timer[i] = ((Switch.hold_timer[i] & ~SM_TIMER_MASK) == SM_FIRST_PRESS) ? SM_SECOND_PRESS : 0;
              SendKey(KEY_SWITCH, i +1, POWER_INV);             // Execute command via MQTT
              mqtt_action = POWER_INV;
            }
          } else {
            if ((Switch.hold_timer[i] & SM_TIMER_MASK)> loops_per_second * Settings.param[P_HOLD_TIME] / 25) {
              if((Switch.hold_timer[i] & ~SM_TIMER_MASK) != SM_SECOND_PRESS) {
                Switch.hold_timer[i]= SM_FIRST_PRESS;
                switchflag = POWER_TOGGLE;                      // Toggle with pushbutton
              }
              else{
                SendKey(KEY_SWITCH, i +1, POWER_100);           // Execute command via MQTT
                mqtt_action = POWER_100;
                Switch.hold_timer[i]= 0;
              }
            } else {
              Switch.hold_timer[i]= 0;
              SendKey(KEY_SWITCH, i +1, POWER_RELEASE);         // Execute command via MQTT
              mqtt_action = POWER_RELEASE;
            }
          }
          Switch.hold_timer[i] = (Switch.hold_timer[i] & ~SM_TIMER_MASK) | loops_per_second * Settings.param[P_HOLD_TIME] / 10;
          break;
        case PUSHON:
          if (PRESSED == button) {
            switchflag = POWER_ON;                              // Power ON with pushbutton to Gnd
          }
          break;
        case PUSHON_INV:
          if (NOT_PRESSED == button) {
            switchflag = POWER_ON;                              // Power ON with releasing pushbutton from Gnd
          }
          break;
        case PUSH_IGNORE:
          Switch.last_state[i] = button;                        // Update switch state before publishing
          MqttPublishSensor();
          break;
        }
        Switch.last_state[i] = button;
      }
      if (switchflag <= POWER_TOGGLE) {
        if (!Settings.flag5.mqtt_switches) {                    // SetOption114 (0) - Detach Switches from relays and enable MQTT action state for all the SwitchModes
          if (!SendKey(KEY_SWITCH, i +1, switchflag)) {         // Execute command via MQTT
            ExecuteCommandPower(i +1, switchflag, SRC_SWITCH);  // Execute command internally (if i < TasmotaGlobal.devices_present)
          }
        } else { mqtt_action = switchflag; }
      }
      if ((mqtt_action != POWER_NONE) && Settings.flag5.mqtt_switches) {  // SetOption114 (0) - Detach Switches from relays and enable MQTT action state for all the SwitchModes
        if (!Settings.flag.hass_discovery) {                    // SetOption19 - Control Home Assistant automatic discovery (See SetOption59)
          char mqtt_state_str[16];
          char *mqtt_state = mqtt_state_str;
          if (mqtt_action <= 3) {
            if (mqtt_action != 3) { SendKey(KEY_SWITCH, i +1, mqtt_action); }
            mqtt_state = SettingsText(SET_STATE_TXT1 + mqtt_action);
          } else {
            GetTextIndexed(mqtt_state_str, sizeof(mqtt_state_str), mqtt_action, kSwitchPressStates);
          }
          Response_P(S_JSON_SVALUE_ACTION_SVALUE, GetSwitchText(i).c_str(), mqtt_state);
          char scommand[10];
          snprintf_P(scommand, sizeof(scommand), PSTR(D_JSON_SWITCH "%d"), i +1);
          MqttPublishPrefixTopicRulesProcess_P(RESULT_OR_STAT, scommand);
        }
        mqtt_action = POWER_NONE;
      }
    }
  }
}

void SwitchLoop(void) {
  if (Switch.present) {
    if (TimeReached(Switch.debounce)) {
      SetNextTimeInterval(Switch.debounce, Settings.switch_debounce);
      SwitchHandler(0);
    }
  }
}

#endif  // SWITCH_V3