/***
 *       ____ ___ ____       _                         _
 *      / ___/ _ \___ \     / \   _ __ ___  _ __   ___| |
 *     | |  | | | |__) |   / _ \ | '_ ` _ \| '_ \ / _ \ |
 *     | |__| |_| / __/   / ___ \| | | | | | |_) |  __/ |
 *      \____\___/_____| /_/__ \_\_| |_| |_| .__/ \___|_|         _
 *     | | | |/ _|_   _| / ___|| |_ _   _| |_| |_ __ _  __ _ _ __| |_
 *     | |_| | |_  | |   \___ \| __| | | | __| __/ _` |/ _` | '__| __|
 *     |  _  |  _| | |    ___) | |_| |_| | |_| || (_| | (_| | |  | |_
 *     |_| |_|_|   |_|   |____/ \__|\__,_|\__|\__\__, |\__,_|_|   \__|
 *                                               |___/
 */

#include "ampel-firmware.h"

/*****************************************************************
 * GPL License                                                   *
 *****************************************************************/
/*
 * This file is part of the "CO2 Ampel" project ( https://transfer.hft-stuttgart.de/gitlab/co2ampel and
 * https://transfer.hft-stuttgart.de/gitlab/co2ampel/ampel-firmware )
 * Copyright (c) 2020 HfT Stuttgart.
 *
 * 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, version 3.
 *
 * 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/>.
 */

/*****************************************************************
 * Authors                                                       *
 *****************************************************************/
/*
 * Eric Duminil
 * Robert Otto
 * Myriam Guedey
 * Tobias Gabriel Erhart
 * Jonas Stave
 * Michael Käppler
 */

/*****************************************************************
 * Configuration                                                 *
 *****************************************************************/
/*
 * Please define settings in 'config.h'.
 * There's an example config file called 'config.example.h'.
 * You can copy 'config.public.h' (stored in Git) to 'config.h' (not stored in Git),
 * and define your credentials and parameters in 'config.h'.
 */

/*****************************************************************
 * Setup                                                         *
 *****************************************************************/
void setup() {
  led_effects::setupOnBoardLED();
  led_effects::onBoardLEDOff();

  Serial.begin(config::bauds);

  web_config::initialize();

  web_config::setWifiConnectionCallback(wifiConnected);

  web_config::setWifiFailCallback(wifiFailed);

  pinMode(0, INPUT); // Flash button (used for forced calibration)

  Serial.println();
  Serial.print(F("Sensor ID: "));
  Serial.println(ampel.sensorId);
  Serial.print(F("Name     : "));
  Serial.println(config::ampel_name());
  Serial.print(F("MAC      : "));
  Serial.println(ampel.macAddress);
  Serial.print(F("Board    : "));
  Serial.println(ampel.board);
  Serial.print(F("Firmware : "));
  Serial.println(ampel.version);

  led_effects::setupRing();

  sensor::initialize();

  csv_writer::initialize(config::ampel_name());

  ntp::initialize();

  if (config::is_wifi_on) {
    wifi::defineCommands();
    web_server::definePages();
    wifi::tryConnection();
  }

#if defined(ESP32)
  if (config::is_lorawan_active()) {
    lorawan::initialize();
  }
#endif
}

/*****************************************************************
 * Main loop                                                     *
 *****************************************************************/
void loop() {
#if defined(ESP32)
  if (config::is_lorawan_active()) {
    //LMIC Library seems to be very sensitive to timing issues, so run it first.
    lorawan::process();

    if (lorawan::waiting_for_confirmation) {
      // If node is waiting for join confirmation from Gateway, nothing else should run.
      return;
    }
  }
#endif
  //NOTE: Loop should never take more than 1000ms. Split in smaller methods and logic if needed.
  //NOTE: Only use millis() for duration comparison, not timestamps comparison. Otherwise, problems happen when millis roll over.
  uint32_t t0 = millis();

  keepServicesAlive();

  // Short press for night mode, Long press for calibration.
  checkFlashButton();

  sensor_console::checkSerialInput();

  if (sensor::processData()) {
    if (config::is_csv_active()) {
      csv_writer::logIfTimeHasCome(sensor::timestamp, sensor::co2, sensor::temperature, sensor::humidity);
    }

    if (config::is_wifi_on && config::is_mqtt_active()) {
      mqtt::publishIfTimeHasCome(sensor::timestamp, sensor::co2, sensor::temperature, sensor::humidity);
    }

#if defined(ESP32)
    if (config::is_lorawan_active()) {
      lorawan::preparePayloadIfTimeHasCome(sensor::co2, sensor::temperature, sensor::humidity);
    }
#endif
  }

  uint32_t duration = millis() - t0;
  if (duration > ampel.max_loop_duration) {
    ampel.max_loop_duration = duration;
    Serial.print(F("Debug - Max loop duration : "));
    Serial.print(ampel.max_loop_duration);
    Serial.println(F(" ms."));
  }
}

/*****************************************************************
 * Callbacks                                                     *
 *****************************************************************/
void wifiConnected() {
  led_effects::showKITTWheel(color::green);
  Serial.println();
  Serial.print(F("WiFi - Connected to "));
  Serial.print(WiFi.SSID());
  Serial.print(F(", IP address: "));
  IPAddress address = WiFi.localIP();
  snprintf(wifi::local_ip, sizeof(wifi::local_ip), "%d.%d.%d.%d", address[0], address[1], address[2], address[3]);
  Serial.println(wifi::local_ip);

  ntp::connect();

  if (config::is_mqtt_active()) {
    mqtt::initialize(ampel.sensorId);
  }

  Serial.print(F("You can access this sensor via http://"));
  Serial.print(config::ampel_name());
  Serial.print(F(".local (might be unstable) or http://"));
  Serial.println(WiFi.localIP());
}

void wifiFailed() {
  // Ampel will go back to Access Point mode for AP_TIMEOUT seconds, and try connection again after
  Serial.print(F("WiFi - Could not connect to "));
  Serial.println(config::selected_ssid());
  led_effects::showKITTWheel(color::red);
}

/*****************************************************************
 * Helper functions                                              *
 *****************************************************************/

/**
 * Checks if flash button has been pressed:
 *   If not, do nothing.
 *   If short press, toggle LED display.
 *   If long press, start calibration process.
 */
void checkFlashButton() {
  if (!digitalRead(0)) { // Button has been pressed
    led_effects::onBoardLEDOn();
    delay(300);
    if (digitalRead(0)) {
      Serial.println(F("Flash has been pressed for a short time. Should toggle night mode."));
      led_effects::toggleNightMode();
      //NOTE: Start Access Point instead?
    } else {
      Serial.println(F("Flash has been pressed for a long time. Keep it pressed for calibration."));
      if (led_effects::countdownToZero()) {
        Serial.println(F("You can now release the button."));
        sensor::startCalibrationProcess();
        led_effects::showKITTWheel(color::red, 2);
      }
    }
    led_effects::onBoardLEDOff();
  }
}

void keepServicesAlive() {
  if (config::is_wifi_on) {
    web_config::update();
    if (wifi::connected()) {
      ntp::update(); // NTP client has its own timer. It will connect to NTP server every 60s.
      if (config::is_mqtt_active()) {
        mqtt::keepConnection(); // MQTT client has its own timer. It will keep alive every 15s.
      }
    }
  }
}