#include <WiFi.h>
#include <ThingSpeak.h>
#define SECRET_SSID "Wokwi-GUEST"
#define SECRET_PASS ""
#define SECRET_CH_ID 2030257
#define SECRET_WRITE_APIKEY "E5BXT8Y4KK8J9LC1"
char ssid[] = SECRET_SSID;
char pass[] = SECRET_PASS;
int keyIndex = 0;
WiFiClient client;
unsigned long myChannelNumber = SECRET_CH_ID;
const char * myWriteAPIKey = SECRET_WRITE_APIKEY;

#define blue 18
#define BPM 35
#define SPO 32
#define buzzer 23

int BPMval;
int SPOval;

void setup(){
  Serial.begin(115200);
  while (!Serial) {
    ;
  }
    WiFi.mode(WIFI_STA);
  ThingSpeak.begin(client);
  pinMode(blue, OUTPUT);  
  pinMode(buzzer, OUTPUT);
}

void loop(){
  if (WiFi.status() !=WL_CONNECTED)
  {
    Serial.print("Attempting to connect to SSID: ");
    Serial.println(SECRET_SSID);
    while(WiFi.status() !=WL_CONNECTED)
    {
      WiFi.begin(ssid, pass);
      Serial.print(".");
      delay(5000);
    }
    Serial.println("\nConnected.");
  }

  BPMval = analogRead(BPM);
  BPMval= map(BPMval, 0, 4095, 0, 140);
  BPMval= constrain(BPMval,0,140);

  SPOval = analogRead(SPO);
  SPOval = map(SPOval, 0, 4095, 0, 100);

  Serial.println("BPM =");
  Serial.println(BPMval);
  Serial.println("SPo2 =" + String(SPOval,1) + "%");
  Serial.println(SPOval);
  Serial.println("---");

  if (BPMval<51){
    digitalWrite(blue, HIGH); // turn on LED
    delay(100);
    digitalWrite(blue, LOW);
    delay(100);
    digitalWrite(buzzer,HIGH);
    }
  else
    digitalWrite(blue, LOW);


  if (BPMval>100) {
    digitalWrite(blue, HIGH);
    delay(100);
    digitalWrite(blue, LOW);
    delay(100); // turn on LED
    digitalWrite(buzzer, HIGH);
    }
  else 
    digitalWrite(blue, LOW);
    
  ThingSpeak.setField(1, BPMval);
  ThingSpeak.setField(2, SPOval);
  int x = ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);
  if(x == 200)
  {
    Serial.println("Channel Update successful.");
  }
  else
  {
    Serial.println("Problem updating channel. HTTP error code" + String(x));
  }
  delay(15000);
}