#include <U8glib.h>
#include <Wire.h>


U8GLIB_SSD1306_128X64 u8g(U8G_I2C_OPT_DEV_0|U8G_I2C_OPT_NO_ACK|U8G_I2C_OPT_FAST);	


int hours = 9;              //initial starting time at 9:30:00
int minutes = 30;
int seconds = 0;
char *number[12] = {"6","5","4","3","2","1","12","11","10","9","8","7"};

const int screen_width = 128;
const int screen_height = 64;
float radius = min(screen_height, screen_width)/2-1;

const int x_center = screen_width / 2;
const int y_center = screen_height / 2;

int x1, y1, x2, y2;
double angle;

void draw(void)
{
     u8g.setFont(u8g_font_4x6);
     u8g.drawStr( 0, 10, "Lhai168");
   
     //u8g.drawCircle(x_center, y_center, radius); 
     u8g.drawCircle(x_center, y_center, 1);        // dot at center of the clock 
     
     for(int i =1; i<=60; i++)                     
     {
        //*****draw tick mark 60 seconds **********
         angle = i*6;                              // 360/60 = 6 degree
         angle = angle * 0.01745233;               // π/180 = 0.0174533  pi to radian
     
         x1 = x_center + (sin(angle) * radius);
         y1 = y_center + (cos(angle) * radius);
      // x2 = x_center + (sin(angle) * (radius-1));
      // y2 = y_center + (cos(angle) * (radius-1));
         x2 = x_center + (sin(angle) * (radius)); // x1 and x2 same position appears as dot
         y2 = y_center + (cos(angle) * (radius)); // y1 and y2 same position appears as dot
    
         u8g.drawLine(x1,y1,x2,y2);
     }


    for(int i =0; i<12; i++)                    
    { 
        //*****draw tick mark 12 hours************   
        angle = i*30;                             // 360/12 = 30 degree
        angle = angle * 0.01745233;               // π/180 = 0.0174533  pi to radian
      
        x1 = x_center + (sin(angle) * radius);
        y1 = y_center + (cos(angle) * radius);
        x2 = x_center + (sin(angle) * (radius - 4));  
        y2 = y_center + (cos(angle) * (radius - 4));  
  
        u8g.drawLine(x1,y1,x2,y2);
  
  
       //*****draw 12-hour Text*******************
  
        x2 = x_center + (sin(angle) * (radius - 8));   
        y2 = y_center + (cos(angle) * (radius - 8)); 

        u8g.setFont(u8g_font_chikita);
        u8g.drawStr(x2-2,y2+3, String(number[i]).c_str()); 
    }

       
    //******Animate moving clock hands (minute/hour)
    //****** Second ********************************
    angle = seconds*6;                                
    angle = angle * 0.01745233;                     
    x2 = x_center + (sin(angle) * (radius - 1));  
    y2 = y_center - (cos(angle) * (radius - 1));      // - minus  for moving clockwise  + for moving anti-clockwise
    u8g.drawLine(x_center, y_center,x2,y2); 

    //***** Minute*****************************
    angle = minutes*6;                              
    angle = angle * 0.01745233;                     
    x2 = x_center + (sin(angle) * (radius - 9));  
    y2 = y_center - (cos(angle) * (radius - 9));  
    u8g.drawLine(x_center, y_center,x2,y2); 

    //***** Hour ******************************
    angle = hours*30 + ((minutes/12) * 6);                              
    angle = angle * 0.01745233;                     
    x2 = x_center + (sin(angle) * (radius /2));  
    y2 = y_center - (cos(angle) * (radius /2));  
    u8g.drawLine(x_center, y_center,x2,y2);

}

void setup() 
{
  
}

void loop() 
{
     seconds +=1;

     if(seconds==60)
     { 
        seconds=seconds-60; minutes +=1;
     }
     if(minutes==60)
     { 
        minutes=0; hours +=1;
     }
     if(hours==24)
     {
        hours=1;
     }
   

     u8g.firstPage();
     do{
         draw();
     }while(u8g.nextPage());

     delay(500);
}