#include <iostream>
#include <vector>
#include <chrono>
#include <cstdlib> // rand()
#include <ctime>   // time()
#include <windows.h>

// === Parameters ===
const int BPM_MIN = 55; // Minimum Normal BPM 
const int BPM_MAX = 110; // Maximum Normal BPM 
const int BPM_TACHYCARDIA = 40; // Minimum BPM for Tachycardia
const int BPM_BRADYCARDIA = 140; // Maximum BPM for Bradycardia
const int SAMPLE_INTERVAL_MS = 1000; // Sampling every 1s
const int THRESHOLD_CARDIAC_ARREST = 2;


// === Initialize random generator ===// === Simulate heart signal from sensor ===
int generateRandomHeartRate() {
    int bpm = rand() % BPM_BRADYCARDIA + 1;  //  génère un BPM entre 0 et 140
    return bpm;
}

// === Simulate buzzer activation ===
void activateBuzzer(bool activationBuz) {
    if (activationBuz) {
        std::cout << " Buzzer activated (CARDIAC ALERT)!" << std::endl;
    } else {
        std::cout << " Buzzer desactivated" << std::endl;
    }
}


// === Simulate vibration motor activation ===
void activateVibration(bool activationVib) {
    if (activationVib) {
        std::cout << " Vibration activated (CARDIAC ALERT)!" << std::endl;
    } else {
        std::cout << " Vibration desactivated" << std::endl;
    }
}

// === Simulate Bluetooth transmission ===
void sendMessageBluetooth(bool urgence) {
    if (urgence) {
        std::cout << " Message Bluetooth send : TRUE (urgence)" << std::endl;
    } else {
        std::cout << " Message Bluetooth send : FALSE (normal)" << std::endl;
    }
}

// send avg bvpm of the last minute
void sendAvgBPM(int avg){
    std::cout << " \n [BLUETOOTH MESSAGE] Average BPM over the last minute : " << avg;
    std::cout << "\n\n" <<std::endl;
}

// === Main program ===
int main() {

    bool pulseDetected = false;
    auto lastPulse = std::chrono::steady_clock::now();

    std::cout << " \n STARTING OF CARDIAC SIMULATION ...\n";
    int i=0;
    int lastBPM;
    int j = 0;
    int time = 0;
    int lastTime = 0;
    std::vector<int> heartRateHistory;
    heartRateHistory.reserve(1728000); //20*24*60*60 secondes de data (20 days)
    int avgBPM = 0;

    while (true) {


        // DHeartrate detection
        if (!pulseDetected) { 
            auto now = std::chrono::steady_clock::now();
            auto intervalle = std::chrono::duration_cast<std::chrono::milliseconds>(now - lastPulse).count();
            
            int bpm = generateRandomHeartRate();
            time++;
            std::cout << " \n -------------- \n Time since device turned ON (in seconds) " << time;
            std::cout << " \n BPM measured : " << bpm;

            if (bpm < BPM_MIN && bpm > BPM_TACHYCARDIA){
                std::cout << " [BRADYCARDIA]"  << std::endl;
                activateVibration(true);
                i=0;

            } else if(bpm < BPM_BRADYCARDIA && bpm > BPM_MAX) {
                std::cout << " [TACHYCARDIA]"  << std::endl;
                activateVibration(true);
                i=0;

            }else if(bpm < BPM_MAX && bpm > BPM_MIN){
                std::cout << " [NORMAL]" << std::endl;
                activateBuzzer(false);
                activateVibration(false);
                sendMessageBluetooth(false);
                i=0;

            } else if (bpm < BPM_TACHYCARDIA){
                if (i=THRESHOLD_CARDIAC_ARREST && lastBPM < BPM_TACHYCARDIA){
                    i=0;
                    std::cout << " \n !! Number = 2 [HEART ATTACK]" << std::endl;
                    activateBuzzer(true);
                    activateVibration(true);
                    sendMessageBluetooth(true);
                }else{
                    i+=1;
                    std::cout << " \n !! Low BPM, emergency alert if number gets to 2:  "<<i << std::endl;
                }  
            }   

            std::cout << std::endl;

            lastPulse = now;
            pulseDetected = true;
            heartRateHistory.push_back(bpm);
            lastBPM =bpm;
        }else {
            pulseDetected = false; // Ready to detect new pulse
        }
        

        if (time>(lastTime + 60)){
            for (j = lastTime; j<time; j++){
                avgBPM = avgBPM + heartRateHistory[j];
            }
            avgBPM = avgBPM/j;
            sendAvgBPM(avgBPM);
            lastTime = time;
        }
        Sleep(SAMPLE_INTERVAL_MS);  // expects milliseconds
    }

    return 0;
}