#include <Arduino.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <WiFi.h>
#include <HTTPClient.h>
#include <ArduinoJson.h>
#include <freeRTOS.h>

#define TIME_SERVER_API "http://worldtimeapi.org/api/timezone/Europe/Prague"

struct Task {
  void (*taskFunction)();
  unsigned long interval; // Interval between task executions in milliseconds
  bool immediateStart;    // Flag for immediate start
  unsigned long nextExecution; // Time of last execution
  bool run = false;
};

Task *tasks = NULL; // Define a pointer for tasks
int numTasks = 0; // Variable to keep track of the number of tasks added
LiquidCrystal_I2C lcd(0x27, 16, 2);
unsigned int uTime;
unsigned int timeDelay;
bool update = false;
String updateLink = "";
bool restart = false;
bool loadLog = false;

void restartBoard()
{
  //Serial.println("turning board off");
  ESP.restart();

}

void taskFunction()
{
  Serial.println("wait");
}

void loadTime()
{
  Serial.println("loading Time");
}

void loadSettings()
{
     Serial.println("loading settings");
    HTTPClient http;
  http.begin("http://script.google.com/macros/s/AKfycbxWBMwXW1kBWtNlN-kGqeoTNL52ckDwrbCG9uWzyMwddqpzwoX2E29mQOHsJ3Pdqw/exec?route=settings");


  int httpCode = http.GET();
  if (httpCode > 0) {
    
    String payload = http.getString();
    DynamicJsonDocument doc(1024);
    deserializeJson(doc, payload);

    JsonArray root = doc.as<JsonArray>();
    update = root[0];
    updateLink = root[1].as<String>();
    restart = root[2];
    loadLog = root [3];

    Serial.println(update);
    Serial.println(updateLink);
    Serial.println(restart);
    Serial.println(loadLog);



  } else {
    Serial.println("Error when loading settings." + http.errorToString(httpCode));

  }

  http.end();
}


void connectToWiFi() {
  WiFi.begin("Wokwi-GUEST", "",6);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");
}


void updateTime()
{
    Serial.println("fetchigTime");
 HTTPClient http;
 timeDelay = millis();
  http.begin(TIME_SERVER_API);


  int httpCode = http.GET();
  if (httpCode > 0) {
    
    String payload = http.getString();
    DynamicJsonDocument doc(1024);
    deserializeJson(doc, payload);

    uTime = doc["unixtime"].as<unsigned int>(); // Store the formatted time
  } else {
    Serial.println("Error fetching time and date: " + http.errorToString(httpCode));
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Date: N/A");
    lcd.setCursor(0, 1);
    lcd.print("Time: N/A");
  }

  http.end();
}


void displayTime()
{
  Serial.println("updatingTime");
  // Calculate time components
  unsigned int accDelay = millis() - timeDelay;
  uTime = uTime + (accDelay/1000) + 3600;
  unsigned long seconds = uTime % 60;
  unsigned long minutes = (uTime / 60) % 60;
  unsigned long hours = (uTime / 3600) % 24;
  unsigned long days = uTime / 86400;

  // Calculate year, month, and day
  unsigned long year = 1970;
  unsigned long daysInYear = 365;
  while (days >= daysInYear) {
    if (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)) {
      if (days >= 366) {
        days -= 366;
      } else {
        break;
      }
    } else {
      days -= 365;
    }
    year++;
    daysInYear = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)) ? 366 : 365;
  }

  unsigned long daysInMonth;
  int month;
  for (month = 1; month <= 12; ++month) {
    daysInMonth = 31;
    if (month == 4 || month == 6 || month == 9 || month == 11) {
      daysInMonth = 30;
    } else if (month == 2) {
      daysInMonth = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)) ? 29 : 28;
    }
    if (days < daysInMonth) {
      break;
    }
    days -= daysInMonth;
  }

  // Construct the date and time strings
  String sseconds = String(seconds);
  if(seconds < 10)
  {
  sseconds = "0" + sseconds;
  }

  String sminutes = String(minutes);
  if(minutes < 10)
  {
  sminutes = "0" + sminutes;
  }
  String dateString = String(year) + "-" + String(month) + "-" + String(days + 1); // Adding 1 because day is 0-indexed
  String timeString = String(hours) + ":" + sminutes + ":" + sseconds;
  
  // Display the date and time on the LCD
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print(dateString);
  lcd.setCursor(0, 1);
  lcd.print(timeString);
}




void setup() {
   lcd.init();
  lcd.backlight();
  Serial.begin(115200);
  Serial.println("Setup done.");
  connectToWiFi();



  // Add tasks to the tasks array
  //addTask(restartBoard, 5000, false); // Task 1 with interval of 0ms (infinite) and immediate start
  addTask(taskFunction, 100, true, true); // Task 2 with interval of 1000ms (1 second) and immediate start
  addTask(updateTime, 10000, false, true); // Task 3 with interval of 10000ms (10 seconds) and immediate start
  addTask(displayTime, 1000,false, true);
  addTask(restartBoard, 0, true, false);;
  addTask(loadSettings, 5000, false, true);
}

void loop() {
  scheduler();  // Execute the scheduler function in a loop
}

void scheduler() {
  

  // Loop through the tasks
  for (int i = 0; i < numTasks; i++) {
    unsigned long currentTime = micros(); // Get the current time
    tasks[i]; // Reference to the current task
    if(tasks[i].run)
    {
      if(tasks[i].nextExecution <= currentTime){
      unsigned long newNextExecution = currentTime + (tasks[i].interval * 1000);
      tasks[i].nextExecution = newNextExecution;
      tasks[i].taskFunction();
      }
    }
  }
}

void addTask(void (*task)(), unsigned long interval, bool immediateStart,bool run) {
  // Allocate memory for a new task
  Task *newTasks = (Task *)realloc(tasks, (numTasks + 1) * sizeof(Task));
  if (newTasks != NULL) {
    tasks = newTasks;
    tasks[numTasks].taskFunction = task;
    tasks[numTasks].interval = interval;
    tasks[numTasks].run = run;
    tasks[numTasks].immediateStart = immediateStart;
    tasks[numTasks].nextExecution = 0; // Initialize lastExecution to 0
    numTasks++; // Increment the number of tasks
  } else {
    //Serial.println("Error: Memory allocation failed.");
  }
  initTask(numTasks - 1);
}

void initTask(int index)
{
  if(tasks[index].immediateStart == true)
  {
    tasks[index].nextExecution = micros();
  }
  else{
    tasks[index].nextExecution = micros() + (tasks[index].interval * 1000);
  }
}