#include <SPI.h>
#include <LoRa.h>
#include <stdlib.h>     /* strtoll */

#define ss 5
#define rst 14
#define dio0 2

const int csPin = 7;          // LoRa radio chip select
const int resetPin = 6;       // LoRa radio reset
const int irqPin = 1;         // change for your board; must be a hardware interrupt pin

byte msgCount = 0;            // count of outgoing messages
int interval = 2000;          // interval between sends
long lastSendTime = 0;        // time of last packet send


// Define LoRa parameters
#define BAND 433E6 // Adjust based on your region

// Definisi Nilai Pin untuk ESP32
#define LED_PIN LED_BUILTIN
#define BUTTON_PIN 4

String SerialData;

void InitializeLoRa(){
  Serial.println("Initializing LoRa...");

  //setup LoRa transceiver module
  LoRa.setPins(csPin, resetPin, irqPin);

  LoRa.setFrequency(BAND);


  // Initialize LoRa
  while (!LoRa.begin(BAND)) {
    Serial.print(".");
    delay(500);
  }

  // register the receive callback
  LoRa.onReceive(onReceive);

  // put the radio into receive mode
  LoRa.receive();
  
}

 void onReceive(int packetSize) {
  if (packetSize == 0) {
    Serial.println("Received 0 packet"); // received a packet
    return;
  }

  // Read packet
  String incoming = "";
  for (int i = 0; i < packetSize; i++) {
    incoming += (char)LoRa.read();
  }

  // Display information
  Serial.print("Message: "); 
  Serial.println(incoming);
  Serial.print("RSSI: "); 
  Serial.println(LoRa.packetRssi());
  Serial.print("SNR: "); 
  Serial.println(LoRa.packetSnr());
  Serial.print("Frequency Error: "); 
  Serial.println(LoRa.packetFrequencyError());
}

void sendMessage(String outgoing){
  LoRa.beginPacket();                   // start packet
  LoRa.print(outgoing);                 // add payload
  LoRa.endPacket();                     // finish packet and send it
  msgCount++;                           // increment message ID
}

String getInputStringLoRa (String desc){
    Serial.print(desc);
    while(!Serial.available());
    String data = Serial.readStringUntil('\n');
    Serial.printf("%s\n",data);
    return data;
}


void handleCommand(String command){
  long sw;
  int level, outputPin;
  int sf;
  long sbw;
  int denominator;
  long length;
  int active;
  uint8_t gain;
  String outgoing;

  String serialData;

  if(command == "a") InitializeLoRa();
  else if (command == "b"){
    sw = getInputStringLoRa("Set Sync Word : ").toInt();

    LoRa.setSyncWord(sw); 
    Serial.printf("Sync Word has been set to %d\n", sw);
  } 
  else if (command == "c"){
    Serial.println("Set TX Power");
    level = getInputStringLoRa("Level : ").toInt();

    outputPin = getInputStringLoRa("Output Pin : ").toInt();

    LoRa.setTxPower(level, outputPin);
    Serial.printf("TX Power has been set to %d Level at Pin %d\n", level, outputPin);
  } 
  else if (command == "d"){
    sf = getInputStringLoRa("Spreading Factor : ").toInt();
    LoRa.setSpreadingFactor(sf); 
    Serial.printf("Spreading Factor has been set to %d\n", sf);
  }
  else if (command == "e"){
    sbw = getInputStringLoRa("Signal Bandwidth : ").toInt();
    LoRa.setSignalBandwidth(sbw);
    Serial.printf("Signal Bandwidth has been set to %d\n", sbw);
  } 
  else if (command == "f"){
    denominator = getInputStringLoRa("Coding Rate : ").toInt();
    LoRa.setCodingRate4(denominator); 
    Serial.printf("Coding Rate has been set to %d\n", denominator);
  } 
  else if (command == "g"){
    length = getInputStringLoRa("Preamble Length : ").toInt();
    LoRa.setPreambleLength(length);
    Serial.printf("Preamble Length has been set to %d\n", length);
  } 
  else if (command == "h"){{
    active = getInputStringLoRa("Enable/Disable CRC (1/0) : ").toInt();
    
    if(active){
      LoRa.enableCrc();
      Serial.println("CRC has been set to active");
    } 
    else{
      LoRa.disableCrc();
      Serial.println("CRC has been set to disable");
    }
  }
    
  }
  else if (command == "i")
  {
    active = getInputStringLoRa("Enable/Disable Invert IQ (1/0) : ").toInt();

    if(active){
      LoRa.enableInvertIQ();
      Serial.println("Invert IQ has been set to active");
    } 
    else{
      LoRa.disableInvertIQ();
      Serial.println("Invet IQ has been set to disable");
    }
  }
  else if (command == "j") LoRa.setGain(gain);
  else if (command == "k") LoRa.idle();
  else if (command == "l") LoRa.sleep();
  else if (command == "m") sendMessage(outgoing);
  else{
    Serial.println("Invalid Input");
    Serial.print("Input : ");
  }
  
}


// Fungsi Input Serial monitor untuk membaca input dari Serial Monitoor
void vTaskSerial(void *parameter) {
  Serial.println("LoRa Duplex Communication");
  Serial.println("a. Initialize LoRa");
  Serial.println("b. Set Sync Word");
  Serial.println("c. Set TX Power");
  Serial.println("d. Set Spreading Factor");
  Serial.println("e. Set Signal Bandwidth");
  Serial.println("f. Set Coding Rate");
  Serial.println("g. Set Preamble Length");
  Serial.println("h. CRC Configuration");
  Serial.println("i. InvertIQ Configuration");
  Serial.println("j. Set Gain");
  Serial.println("k. Set to Idle");
  Serial.println("l. Set to Sleep");
  Serial.println("m. Send a Message");
  Serial.println("Please input the characters only like 'a', 'b', 'c'");
  Serial.print("Input : ");

  while (1) { // Looping
  
    // See if there are things in the input serial buffer
    if (Serial.available() > 0) {

      SerialData = Serial.readStringUntil('\n');
      SerialData.trim();
      Serial.println(SerialData); 
      handleCommand(SerialData);
      SerialData = "";
    }
   // Delay kecil untuk menghindar busy-wait
    vTaskDelay(pdMS_TO_TICKS(10)); // Delay 10 ms
  }
}



void setup() {

  Serial.begin(115200); // Set Baud Rate ke 9600
  while (!Serial);

  
  
  // Membuat Task Serial
  xTaskCreatePinnedToCore(
    vTaskSerial,
    "Input Serial Monitor Task ",
    100000, /* Stack size in words */
    NULL, /* Task input parameter */
    2, /* Priority of the task */
    NULL, /* Task handle. */
    0 /* Core where the task should run */
  );

  vTaskDelete(NULL); 
}

void loop() {
  // if (millis() - lastSendTime > interval) {
  //   String message = "HeLoRa World! ";   // send a message
  //   message += msgCount;
  //   sendMessage(message);
  //   Serial.println("Sending " + message);
  //   lastSendTime = millis();            // timestamp the message
  //   interval = random(2000) + 1000;    // 2-3 seconds
  //   msgCount++;
  // }
}