#include <Arduino.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define LED_PIN 25
#define SDA_PIN 21  // 0 wemosLolin32 I2C1
#define SCL_PIN 22  // 4 wemoslolin32 I2C1

// Setup Oled display 128x64
#define OLED_RESET -1        // Reset pin # (or -1 if sharing Arduino reset pin)
#define SCREEN_ADDRESS 0x3C  //< See datasheet for Address; 0x3D for 128x64, 0x3C for 128x32
#define SCREEN_WIDTH 128     // OLED display width, in pixels
#define SCREEN_HEIGHT 64     // OLED display height, in pixels
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

float BaroPres = 1010.12;
float Humidity = 56.10;
float Temperature = 23.32;

String TrendDisp = "langzaam ";
int TrendUp = 24; //arrow up
int TrendDown = 25; //arrow down


bool displayState = false;

unsigned long lastTime10sec = 0;
unsigned long timerDelay10sec = 10 * 1000;  //10 sec delay

void initDisplay() {
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  // Clear the buffer.
  display.clearDisplay();
  display.setRotation(0);  //0= no rotation,1=90deg clockwise,2=180deg upside down,3=90(270)deg anti-clockwise
  display.display();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(20, 30);  //horz, vert
  display.println("weerstation");
  display.display();
  delay(1000);
  //display.clearDisplay();
  //display.display();
}

void setupTime() {
  const char *ntpServer = "pool.ntp.org";
  const long gmtOffset_sec = 3600;      // 1h offset with GMT
  const int daylightOffset_sec = 3600;  //3600 = summertime, 0 = wintertime

  // Init and get the time
  //configTime(timezone, dst, "pool.ntp.org","time.nist.gov");
  configTime(gmtOffset_sec, daylightOffset_sec, ntpServer);
  display.println("\nWaiting for NTP...");
}

void displayTime() {

  time_t now = time(nullptr);
  struct tm *p_tm = localtime(&now);
  int r = 35;

  // Now draw the clock face
  display.drawCircle(display.width() / 2, display.height() / 2, 2, WHITE);
  //
  //hour ticks
  for (int z = 0; z < 360; z = z + 30) {
    //Begin at 0° and stop at 360°
    float angle = z;

    angle = (angle / 57.29577951);  //Convert degrees to radians
    int x2 = (64 + (sin(angle) * r));
    int y2 = (32 - (cos(angle) * r));
    int x3 = (64 + (sin(angle) * (r - 5)));
    int y3 = (32 - (cos(angle) * (r - 5)));
    display.drawLine(x2, y2, x3, y3, WHITE);
  }
  // display second hand
  float angle = p_tm->tm_sec * 6;
  angle = (angle / 57.29577951);  //Convert degrees to radians
  int x3 = (64 + (sin(angle) * (r)));
  int y3 = (32 - (cos(angle) * (r)));
  display.drawLine(64, 32, x3, y3, WHITE);
  //
  // display minute hand
  angle = p_tm->tm_min * 6;
  angle = (angle / 57.29577951);  //Convert degrees to radians
  x3 = (64 + (sin(angle) * (r - 3)));
  y3 = (32 - (cos(angle) * (r - 3)));
  display.drawLine(64, 32, x3, y3, WHITE);
  //
  // display hour hand
  angle = p_tm->tm_hour * 30 + int((p_tm->tm_min / 12) * 6);
  angle = (angle / 57.29577951);  //Convert degrees to radians
  x3 = (64 + (sin(angle) * (r - 11)));
  y3 = (32 - (cos(angle) * (r - 11)));
  display.drawLine(64, 32, x3, y3, WHITE);

  display.setTextSize(1);
  display.setCursor((display.width() / 2) + 10, (display.height() / 2) - 3);
  display.print(p_tm->tm_mday);

  // update display with all data
  display.display();
  display.clearDisplay();
}

void displayData(){
  display.clearDisplay();
  
  //display.display();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0,0);  //horz, vert
  display.print("Temperatuur ");
  display.print(Temperature);
  display.print(" C");
  display.setCursor(0,14);  //horz, vert
  display.print("Vochtigheid ");
  display.print(Humidity);
  display.print(" %");
  display.setCursor(0,28);  //horz, vert
  display.print("Barometer ");
  display.print(BaroPres);
  display.print(" hPa");
  display.setCursor(0,42);  //horz, vert
  display.print("Comfort ");
  //display.print(BaroPres);
  display.print("prima");
  display.setCursor(0,56);  //horz, vert
  display.print("Trend ");
  display.print(TrendDisp);
  display.print((char)TrendDown);
  display.display();
 
}

void setup() {
  Serial.begin(115200);

  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C))
  {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;); // Don't proceed, loop forever
  }
  display.clearDisplay();
  initDisplay();
  setupTime();
  

  // configure Arduino LED pin for output
  pinMode(LED_PIN, OUTPUT);
}

void loop() {
  //displayTime();
  
  
if (displayState == false) {
    displayTime();
    digitalWrite(18, HIGH);  // activity led
  }

  if (displayState == true) {
    displayData();
    digitalWrite(18, LOW);
  }


  if ((millis() - lastTime10sec) > timerDelay10sec) {
    display.clearDisplay();
    display.display();
    displayState = !displayState;
    lastTime10sec = millis();
  }
 
}