/*
 * Created by ArduinoGetStarted.com
 *
 * This example code is in the public domain
 *
 * Tutorial page: https://arduinogetstarted.com/tutorials/arduino-potentiometer
 */

float floatMap(float x, float in_min, float in_max, float out_min, float out_max) {
  return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
}

// the setup routine runs once when you press reset:
void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
}

// the loop routine runs over and over again forever:
void loop() {
  // read the input on analog pin A0:
  int analogValue = analogRead(A0);
  // Rescale to potentiometer's voltage (from 0V to 5V):
  float voltage = floatMap(analogValue, 0, 1023, 0, 5);

  // print out the value you read:
  Serial.print("Analog: ");
  Serial.print(analogValue);
  Serial.print(", Voltage: ");
  Serial.println(voltage);
  delay(1000);
}

#include <BLEDevice.h>
#include <BLEUtils.h>
#include <BLEServer.h>

const int buttonPin = D6;  // Button pin, ESP32-C3 pin D6
int buttonState = 0;       // Initial state of the button
int lastButtonState = LOW; // Previous state of the button
bool stateChanged = false; // Flag to track if the button state has changed

#define SERVICE_UUID        "4fafc201-1fb5-459e-8fcc-c5c9c331914b"
#define CHARACTERISTIC_UUID "beb5483e-36e1-4688-b7f5-ea07361b26a8"

BLEServer *pServer;
BLEService *pService;
BLECharacteristic *pCharacteristic;

void setup() {
  pinMode(buttonPin, INPUT);
  Serial.begin(115200);
  Serial.println("Starting BLE Server!");

  BLEDevice::init("ESP32-BLE-Server");
  pServer = BLEDevice::createServer();
  pService = pServer->createService(SERVICE_UUID);
  pCharacteristic = pService->createCharacteristic(
                                         CHARACTERISTIC_UUID,
                                         BLECharacteristic::PROPERTY_READ |
                                         BLECharacteristic::PROPERTY_NOTIFY
                                       );
  pCharacteristic->setValue("Button Not Pressed");
  pService->start();

  BLEAdvertising *pAdvertising = BLEDevice::getAdvertising();
  pAdvertising->addServiceUUID(SERVICE_UUID);
  pAdvertising->setScanResponse(true);
  pAdvertising->setMinPreferred(0x06);  // Functions that help with iPhone connections issue
  pAdvertising->setMinPreferred(0x12);
  BLEDevice::startAdvertising();
}

void loop() {
  buttonState = digitalRead(buttonPin); // Read the state of the button

  if (buttonState != lastButtonState) { // If button state has changed
    stateChanged = true;
    lastButtonState = buttonState; // Update lastButtonState
  }

  if (stateChanged) {
    if (buttonState == HIGH) { // If the button is pressed
      pCharacteristic->setValue("Button Pressed");
      Serial.println("Button is pressed"); 
    } else {
      pCharacteristic->setValue("Button Not Pressed");
      Serial.println("Button is not pressed");
    }

    pCharacteristic->notify(); // Notify clients about the changed value
    stateChanged = false; // Reset stateChanged flag
  }

  delay(100); // Add a small delay to debounce the button and prevent flickering
}

#include "BLEDevice.h"

/* Specify the Service UUID of Server */
static BLEUUID serviceUUID("4fafc201-1fb5-459e-8fcc-c5c9c331914b");
/* Specify the Characteristic UUID of Server */
static BLEUUID    charUUID("beb5483e-36e1-4688-b7f5-ea07361b26a8");

static boolean doConnect = false;
static boolean connected = false;
static boolean doScan = false;
static BLERemoteCharacteristic* pRemoteCharacteristic;
static BLEAdvertisedDevice* myDevice;

static void notifyCallback(BLERemoteCharacteristic* pBLERemoteCharacteristic,
                            uint8_t* pData, size_t length, bool isNotify)
{
  Serial.print("Notify callback for characteristic ");
  Serial.print(pBLERemoteCharacteristic->getUUID().toString().c_str());
  Serial.print(" of data length ");
  Serial.println(length);
  Serial.print("data: ");
  Serial.println((char*)pData);
}

class MyClientCallback : public BLEClientCallbacks
{
  void onConnect(BLEClient* pclient)
  {
    
  }

  void onDisconnect(BLEClient* pclient)
  {
    connected = false;
    Serial.println("onDisconnect");
  }
};

/* Start connection to the BLE Server */
bool connectToServer()
{
  Serial.print("Forming a connection to ");
  Serial.println(myDevice->getAddress().toString().c_str());
    
  BLEClient*  pClient  = BLEDevice::createClient();
  Serial.println(" - Created client");

  pClient->setClientCallbacks(new MyClientCallback());

    /* Connect to the remote BLE Server */
  pClient->connect(myDevice);  // if you pass BLEAdvertisedDevice instead of address, it will be recognized type of peer device address (public or private)
  Serial.println(" - Connected to server");

    /* Obtain a reference to the service we are after in the remote BLE server */
  BLERemoteService* pRemoteService = pClient->getService(serviceUUID);
  if (pRemoteService == nullptr)
  {
    Serial.print("Failed to find our service UUID: ");
    Serial.println(serviceUUID.toString().c_str());
    pClient->disconnect();
    return false;
  }
  Serial.println(" - Found our service");


  /* Obtain a reference to the characteristic in the service of the remote BLE server */
  pRemoteCharacteristic = pRemoteService->getCharacteristic(charUUID);
  if (pRemoteCharacteristic == nullptr)
  {
    Serial.print("Failed to find our characteristic UUID: ");
    Serial.println(charUUID.toString().c_str());
    pClient->disconnect();
    return false;
  }
  Serial.println(" - Found our characteristic");

  /* Read the value of the characteristic */
  /* Initial value is 'Hello, World!' */
  if(pRemoteCharacteristic->canRead())
  {
    std::string value = pRemoteCharacteristic->readValue();
    Serial.print("The characteristic value was: ");
    Serial.println(value.c_str());
  }

  if(pRemoteCharacteristic->canNotify())
  {
    pRemoteCharacteristic->registerForNotify(notifyCallback);

  }

    connected = true;
    return true;
}
/* Scan for BLE servers and find the first one that advertises the service we are looking for. */
class MyAdvertisedDeviceCallbacks: public BLEAdvertisedDeviceCallbacks
{
 /* Called for each advertising BLE server. */
  void onResult(BLEAdvertisedDevice advertisedDevice)
  {
    Serial.print("BLE Advertised Device found: ");
    Serial.println(advertisedDevice.toString().c_str());

    /* We have found a device, let us now see if it contains the service we are looking for. */
    if (advertisedDevice.haveServiceUUID() && advertisedDevice.isAdvertisingService(serviceUUID))
    {
      BLEDevice::getScan()->stop();
      myDevice = new BLEAdvertisedDevice(advertisedDevice);
      doConnect = true;
      doScan = true;

    }
  }
};


void setup()
{
  Serial.begin(115200);
  Serial.println("Starting Arduino BLE Client application...");
  BLEDevice::init("ESP32-BLE-Client");

  /* Retrieve a Scanner and set the callback we want to use to be informed when we
     have detected a new device.  Specify that we want active scanning and start the
     scan to run for 5 seconds. */
  BLEScan* pBLEScan = BLEDevice::getScan();
  pBLEScan->setAdvertisedDeviceCallbacks(new MyAdvertisedDeviceCallbacks());
  pBLEScan->setInterval(1349);
  pBLEScan->setWindow(449);
  pBLEScan->setActiveScan(true);
  pBLEScan->start(5, false);
}


void loop()
{

  /* If the flag "doConnect" is true, then we have scanned for and found the desired
     BLE Server with which we wish to connect.  Now we connect to it.  Once we are 
     connected we set the connected flag to be true. */
  if (doConnect == true)
  {
    if (connectToServer())
    {
      Serial.println("We are now connected to the BLE Server.");
    } 
    else
    {
      Serial.println("We have failed to connect to the server; there is nothin more we will do.");
    }
    doConnect = false;
  }

  /* If we are connected to a peer BLE Server, update the characteristic each time we are reached
     with the current time since boot */
  if (connected)
  {
    String newValue = "Time since boot: " + String(millis()/2000);
    Serial.println("Setting new characteristic value to \"" + newValue + "\"");
    
    /* Set the characteristic's value to be the array of bytes that is actually a string */
    pRemoteCharacteristic->writeValue(newValue.c_str(), newValue.length());
    /* You can see this value updated in the Server's Characteristic */
  }
  else if(doScan)
  {
    BLEDevice::getScan()->start(0);  // this is just example to start scan after disconnect, most likely there is better way to do it in arduino
  }
  
  delay(2000); /* Delay a second between loops */
}

//Sensor sending device
#include <BLEDevice.h>
#include <BLEUtils.h>
#include <BLEServer.h>
const int buttonPin = D6;   // Button pin, ESP32-C3 pin D6
int buttonState = 0;        // Initial state of the button
int lastButtonState = LOW;  // Previous state of the button
bool stateChanged = false;  // Flag to track if the button state has changed
uint64_t prevMillis = 0;

#define SERVICE_UUID "4fafc201-1fb5-459e-8fcc-c5c9c331914b"
#define CHARACTERISTIC_UUID "beb5483e-36e1-4688-b7f5-ea07361b26a8"


BLEServer *pServer;
BLEService *pService;
BLECharacteristic *pCharacteristic;

long result;          //variable for the result of the tx_rx measurement.
int analog_pin = A0;  //  GPIO 27 of the XIA0 RP2040 or ESP32-C3 pin A1
int tx_pin = D1;      //     GPIO 28 of the XIAO RP2040 or ESP32-C3 pin D2

long tx_rx() {  //Function to execute rx_tx algorithm and return a value
                //that depends on coupling of two electrodes.
                //Value returned is a long integer.
  int read_high;
  int read_low;
  int diff;
  long int sum;
  int N_samples = 100;  //Number of samples to take.  Larger number slows it down, but reduces scatter.

  sum = 0;

  for (int i = 0; i < N_samples; i++) {
    digitalWrite(tx_pin, HIGH);          //Step the voltage high on conductor 1.
    read_high = analogRead(analog_pin);  //Measure response of conductor 2.
    delayMicroseconds(100);              //Delay to reach steady state.
    digitalWrite(tx_pin, LOW);           //Step the voltage to zero on conductor 1.
    read_low = analogRead(analog_pin);   //Measure response of conductor 2.
    diff = read_high - read_low;         //desired answer is the difference between high and low.
    sum += diff;                         //Sums up N_samples of these measurements.
  }
  return sum;
}  //End of tx_rx function.

void setup() {
  pinMode(buttonPin, INPUT);
  pinMode(tx_pin, OUTPUT);  //Pin 2 provides the voltage step

  Serial.begin(115200);
  Serial.println("Starting BLE Server!");


  BLEDevice::init("ESP32-BLE-Server");
  pServer = BLEDevice::createServer();
  pService = pServer->createService(SERVICE_UUID);
  pCharacteristic = pService->createCharacteristic(
    CHARACTERISTIC_UUID,
    BLECharacteristic::PROPERTY_READ | BLECharacteristic::PROPERTY_NOTIFY);
  pCharacteristic->setValue("Button Not Pressed");
  pService->start();


  BLEAdvertising *pAdvertising = BLEDevice::getAdvertising();
  pAdvertising->addServiceUUID(SERVICE_UUID);
  pAdvertising->setScanResponse(true);
  pAdvertising->setMinPreferred(0x06);  // Functions that help with iPhone connections issue
  pAdvertising->setMinPreferred(0x12);
  BLEDevice::startAdvertising();
}


void loop() {
 
  buttonState = digitalRead(buttonPin);  // Read the state of the button
  result = tx_rx();
  result = map(result, 1000, 50000, 0, 1024);  //I recommend mapping the values of the two copper plates, it will depend on their size


  if (buttonState != lastButtonState) {  // If button state has changed
    stateChanged = true;
    lastButtonState = buttonState;  // Update lastButtonState
  }

  String sensorValueString(result);

   //if (buttonState == HIGH) {  // If the button is pressed
      pCharacteristic->setValue(sensorValueString.c_str());
      Serial.println(sensorValueString);
   // } else {
    //  pCharacteristic->setValue("Button Not Pressed");
   //   Serial.println("Button is not pressed");
 //   }


    pCharacteristic->notify();  // Notify clients about the changed value
  // stateChanged = false;       // Reset stateChanged flag
  //}

  //delay(100);  // Add a small delay to debounce the button and prevent flickering
}

#include "BLEDevice.h"

/* Specify the Service UUID of Server */
static BLEUUID serviceUUID("4fafc201-1fb5-459e-8fcc-c5c9c331914b");
/* Specify the Characteristic UUID of Server */
static BLEUUID charUUID("beb5483e-36e1-4688-b7f5-ea07361b26a8");

static boolean doConnect = false;
static boolean connected = false;
static boolean doScan = false;
static BLERemoteCharacteristic* pRemoteCharacteristic;
static BLEAdvertisedDevice* myDevice;

static void notifyCallback(BLERemoteCharacteristic* pBLERemoteCharacteristic,
                           uint8_t* pData, size_t length, bool isNotify) {
 // Serial.print("Notify callback for characteristic ");
 // Serial.print(pBLERemoteCharacteristic->getUUID().toString().c_str());
 /// Serial.print(" of data length ");
 // Serial.println(length);
// Serial.print("data: ");
  Serial.println((char*)pData);
  String sensorValueString(pData);
  int sensorValue = sensorValueString.toInt();
}

class MyClientCallback : public BLEClientCallbacks {
  void onConnect(BLEClient* pclient) {
  }

  void onDisconnect(BLEClient* pclient) {
    connected = false;
    Serial.println("onDisconnect");
  }
};

/* Start connection to the BLE Server */
bool connectToServer() {
  Serial.print("Forming a connection to ");
  Serial.println(myDevice->getAddress().toString().c_str());

  BLEClient* pClient = BLEDevice::createClient();
  Serial.println(" - Created client");

  pClient->setClientCallbacks(new MyClientCallback());

  /* Connect to the remote BLE Server */
  pClient->connect(myDevice);  // if you pass BLEAdvertisedDevice instead of address, it will be recognized type of peer device address (public or private)
  Serial.println(" - Connected to server");

  /* Obtain a reference to the service we are after in the remote BLE server */
  BLERemoteService* pRemoteService = pClient->getService(serviceUUID);
  if (pRemoteService == nullptr) {
    Serial.print("Failed to find our service UUID: ");
    Serial.println(serviceUUID.toString().c_str());
    pClient->disconnect();
    return false;
  }
  Serial.println(" - Found our service");


  /* Obtain a reference to the characteristic in the service of the remote BLE server */
  pRemoteCharacteristic = pRemoteService->getCharacteristic(charUUID);
  if (pRemoteCharacteristic == nullptr) {
    Serial.print("Failed to find our characteristic UUID: ");
    Serial.println(charUUID.toString().c_str());
    pClient->disconnect();
    return false;
  }
  Serial.println(" - Found our characteristic");

  /* Read the value of the characteristic */
  /* Initial value is 'Hello, World!' */
  if (pRemoteCharacteristic->canRead()) {
    std::string value = pRemoteCharacteristic->readValue();
    Serial.print("The characteristic value was: ");
    Serial.println(value.c_str());
  }

  if (pRemoteCharacteristic->canNotify()) {
    pRemoteCharacteristic->registerForNotify(notifyCallback);
  }

  connected = true;
  return true;
}
/* Scan for BLE servers and find the first one that advertises the service we are looking for. */
class MyAdvertisedDeviceCallbacks : public BLEAdvertisedDeviceCallbacks {
  /* Called for each advertising BLE server. */
  void onResult(BLEAdvertisedDevice advertisedDevice) {
    Serial.print("BLE Advertised Device found: ");
    Serial.println(advertisedDevice.toString().c_str());

    /* We have found a device, let us now see if it contains the service we are looking for. */
    if (advertisedDevice.haveServiceUUID() && advertisedDevice.isAdvertisingService(serviceUUID)) {
      BLEDevice::getScan()->stop();
      myDevice = new BLEAdvertisedDevice(advertisedDevice);
      doConnect = true;
      doScan = true;
    }
  }
};


void setup() {
  Serial.begin(115200);
  Serial.println("Starting Arduino BLE Client application...");
  BLEDevice::init("ESP32-BLE-Client");

  /* Retrieve a Scanner and set the callback we want to use to be informed when we
     have detected a new device.  Specify that we want active scanning and start the
     scan to run for 5 seconds. */
  BLEScan* pBLEScan = BLEDevice::getScan();
  pBLEScan->setAdvertisedDeviceCallbacks(new MyAdvertisedDeviceCallbacks());
  pBLEScan->setInterval(1349);
  pBLEScan->setWindow(449);
  pBLEScan->setActiveScan(true);
  pBLEScan->start(5, false);
}


void loop() {

  /* If the flag "doConnect" is true, then we have scanned for and found the desired
     BLE Server with which we wish to connect.  Now we connect to it.  Once we are 
     connected we set the connected flag to be true. */
  if (doConnect == true) {
    if (connectToServer()) {
      Serial.println("We are now connected to the BLE Server.");
    } else {
      Serial.println("We have failed to connect to the server; there is nothin more we will do.");
    }
    doConnect = false;
  }

  /* If we are connected to a peer BLE Server, update the characteristic each time we are reached
     with the current time since boot */
  if (connected) {
    String newValue = "Time since boot: " + String(millis() / 2000);
  //  Serial.println("Setting new characteristic value to \"" + newValue + "\"");

    /* Set the characteristic's value to be the array of bytes that is actually a string */
    pRemoteCharacteristic->writeValue(newValue.c_str(), newValue.length());
    /* You can see this value updated in the Server's Characteristic */
  } else if (doScan) {
    BLEDevice::getScan()->start(0);  // this is just example to start scan after disconnect, most likely there is better way to do it in arduino
  }

  delay(2000); /* Delay a second between loops */
}