// Standard ESP8266 libs
#include <ESP8266mDNS.h>
#include <ESP8266HTTPUpdateServer.h>
#include <ESP8266WiFi.h>
#include <DNSServer.h>
#include <ESP8266WebServer.h>

// External libs
// We decided to put these libs inside the project folder, because we have a lot
// of issues with finding the right libs (some libs need a specific version, some
// libs have no unique name, some libs are broken, ...). This is not a fine
// software engineering practice, but it was too much of a hassle to get this right,
// so we decided to put everything in version control. This way, we also can control
// the version of the lib, which makes the build process of this project more
// robust to changes.
// IMPORTANT: You need to set the sketch location of your Arduino IDE to the firmware
// folder in order to use the libs. (File -> Preferences -> Sketchbook Location)
#include <WiFiClient.h>          // WiFiClient
#include <WiFiManager.h>         // WiFiManager

// Project includes
#include "config.h"

// IMPORTANT: If you compile the sourcecode and it can't find this file, this is
// intentional :) You need to create a config_user.h with your own settings. Use the
// config_user.h.example as a starting point.
#include "config_user.h"

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

/**
 * Whishlist:
 * - Webserver for /metrics endpoint (Prometheus)
 * - Show current sensor values over simple webpage
 * - Push sensor values to various 3rd party services (https://openweathermap.org/)
 * - MQTT?
 *
 * - Buffer sensor values if there is no WIFI connection
 * - Configure weather station over http webinterface
 * - OTA firmware update
 *
 * TODO:
 * - https://sminghub.github.io/Sming/about/
 * - https://github.com/marvinroger/homie-esp8266
 */

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

const uint8_t VALUES = 8;
float currentSensorData[VALUES] = {0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0};
float (*sensors[VALUES])() = {};

uint16_t update_sensor_cnt      = 0;
uint16_t update_webserver_cnt   = 0;

WiFiManager wifiManager;

#ifdef WEBUPDATER_FEATURE
String localIP = "127.0.0.1";
#endif
//*************************************************************************//

void debug(String x) {
#ifdef DEBUG
  Serial.println(x);
#endif
}


void setup() {

  // Erase WiFi Credentials (maybe this will work ...)
  //WiFi.disconnect(true);
  //delay(2000);
  //ESP.reset();

#if defined(DEBUG) || defined(SERIAL_FEATURE)
  Serial.begin(115200);
#endif

  // Pin settings
  pinMode(BAT_CHARGED_PIN, INPUT_PULLUP);
  pinMode(BAT_CHARGING_PIN, INPUT_PULLUP);
  pinMode(STATUS_LED_PIN, OUTPUT);
  pinMode(ANEMOMETER_PIN, INPUT_PULLUP);
  pinMode(A0, INPUT);

  digitalWrite(STATUS_LED_PIN, LOW);

#ifdef BATTERY_POWERED
  criticalBatCheck();
#endif
  // Establish WiFi connection
  String wifiName = "oko-weather-" + DEVICE_NAME;

  wifiManager.setMinimumSignalQuality(16);
  wifiManager.setConnectTimeout(WIFI_AUTOCONNECT_TIMEOUT_S); // the time in seconds to wait for the known wifi connection
  wifiManager.setTimeout(WIFI_CONFIG_PORTAL_TIMEOUT_S); // the time in seconds to wait for the user to configure the device

  if (!wifiManager.autoConnect(wifiName.c_str(), "DEADBEEF")) {
    debug("WiFi connection failed, going into deep sleep ...");
    // If autoconnect to WLAN failed and no client connected, go to deep sleep
    ESP.deepSleep(POWERSAVING_SLEEP_S * 1000000, WAKE_RF_DEFAULT);
    delay(100);
  }

  debug("Connected!");

#ifdef INFLUXDB_FEATURE
  influxdb_begin();
#endif

  // Initialize and configure the sensors
#ifdef SENSOR_APDS9930
  if (sensor_apds9930_begin()) {
    sensors[SENSOR_LIGHT] = &apds9930_light;
  }
#endif

#ifdef SENSOR_APDS9960
  if (sensor_apds9960_begin()) {
    sensors[SENSOR_LIGHT] = &apds9930_light;
  }
#endif

#ifdef SENSOR_BME280
  //Temperature + pressure
  if (sensor_bme280_begin(BME_ADDRESS)) {
    sensors[SENSOR_TEMPERATURE] = &bme280_temperature;
    sensors[SENSOR_HUMIDITY] = &bme280_humidity;
    sensors[SENSOR_PRESSURE] = &bme280_pressure;
  }
#endif

#ifdef SENSOR_WIND
  sensors[SENSOR_WINDSPEED] = &wind_speed;
#endif

#ifdef SENSOR_BATTERY
  sensors[SENSOR_BAT_VOLTAGE] = &battery_voltage;
  sensors[SENSOR_BATCHARGESTATE] = &battery_charging;
  sensors[SENSOR_ESAVEMODE] = &isEnergySavingMode;
#endif

#ifdef WEBUPDATER_FEATURE
#ifndef BATTERY_POWERED
  setupWebUpdater();
  localIP = WiFi.localIP().toString();
#endif
#endif

  //It's magic! leave in
  delay(100);

#ifdef BATTERY_POWERED
  debug("battery powered");
  _loop();

  digitalWrite(STATUS_LED_PIN, LOW);

  criticalBatCheck();

  WiFi.mode(WIFI_OFF);
  WiFi.forceSleepBegin();

  debug("deep sleep");

  // the ESP.deepSleep requires microseconds as input, after the sleep the system will run into the setup routine
  ESP.deepSleep(POWERSAVING_SLEEP_S * 1000000, WAKE_RF_DEFAULT);
  delay(100);
#endif
}

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

#ifdef BATTERY_POWERED
void criticalBatCheck() {
  float volt = battery_voltage();
  if (volt <= BAT_EMERGENCY_DEEPSLEEP_VOLTAGE) {
    debug("Bat Voltage: " + String(volt) + " V");
    debug("Low battery, going into deep sleep.");
    // Casting to an unsigned int, so it fits into the integer range
    ESP.deepSleep(1U * EMERGENCY_SLEEP_S * 1000000); // battery low, shutting down
    delay(100);
  }
}
#endif


void loop() {
#ifdef BATTERY_POWERED
  delay(50);
  return;
#endif

#ifdef WEBUPDATER_FEATURE
  if (UPDATE_WEBSERVER_INTVERVAL_S * 1000 / DELAY_LOOP_MS <= update_webserver_cnt) {
    update_webserver_cnt = 0;
    doWebUpdater();
  }
#endif


  _loop();

  //Needed to give WIFI time to function properly
  delay(DELAY_LOOP_MS);

  update_sensor_cnt++;

#ifdef WEBUPDATER_FEATURE
  update_webserver_cnt++;
#endif
}

void _loop() {

#ifndef BATTERY_POWERED
  if (UPDATE_SENSOR_INTERVAL_S * 1000 / DELAY_LOOP_MS > update_sensor_cnt) {
    return;
  }
#endif


#ifdef defined(BATTERY_POWERED) && defined(SENSOR_WIND)
  if (energySavingMode() == 1) {
    // Disable expensive tasks
    sensors[SENSOR_WINDSPEED] = 0;
  } else {
    sensors[SENSOR_WINDSPEED] = &wind_speed;
  }
#endif

  update_sensor_cnt = 0;

  for (uint8_t i = 0; i < VALUES; i++) {
    if (sensors[i]) {
      currentSensorData[i] = sensors[i]();
    } else {
      currentSensorData[i] = 0xFFFFFFFF;
    }
  }

#ifdef SERIAL_FEATURE
  logToSerial(currentSensorData);
#endif

  delay(100);

#ifdef INFLUXDB_FEATURE
  pushToInfluxDB(DEVICE_NAME, currentSensorData);
#endif

#ifdef WEBUPDATER_FEATURE
  setSensorData(DEVICE_NAME, localIP, currentSensorData);
#endif
}

void logToSerial(float sensorValues[]) {
  Serial.println("");
  Serial.println("Current readings:");
  Serial.println("Temperature: " + String(sensorValues[SENSOR_TEMPERATURE]) + " °C");
  Serial.println("Humidity: " + String(sensorValues[SENSOR_HUMIDITY]) + " %");
  Serial.println("Light: " + String(sensorValues[SENSOR_LIGHT]) + " Lux");
  Serial.println("Windspeed: " + String(sensorValues[SENSOR_WINDSPEED]) + " km/h");
  Serial.println("Pressure: " + String(sensorValues[SENSOR_PRESSURE]) + " hPa");
  Serial.println("Bat Voltage: " + String(sensorValues[SENSOR_BAT_VOLTAGE]) + " V");
  Serial.println("Bat charge state: " + String(sensorValues[SENSOR_BATCHARGESTATE]));
  Serial.println("Energy saving: " + String(sensorValues[SENSOR_ESAVEMODE]));
}