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// Plotclock
// cc - by Johannes Heberlein 2014 ported by Chris Dick
// v 1.0
// thingiverse.com/joo   wiki.fablab-nuernberg.de

// units: mm; microseconds; radians
// origin: bottom left of drawing surface (see sketchUp file)

// todo detail m3, info grafik winkel, kalibr 

#include "mbed.h"

// #define CALIBRATION

#define SERVOFAKTOR 650

// length of arms
#define L1 35
#define L2 55.1
#define L3 13.2

// origin points of left and right servo 
#define O1X 22
#define O1Y -25
#define O2X 47
#define O2Y -25
// When in calibration mode, adjust the NULL-values so that the servo arms are at all times parallel
// either to the X or Y axis
// Zero-position of left and right servo
#define SERVOLEFTNULL 1890
#define SERVORIGHTNULL 960

// lift positions of lifting servo
#define LIFT0 1080// on drawing surface
#define LIFT1 925// between numbers
#define LIFT2 725
/* going towards sweeper */

/* speed of liftimg arm, higher is slower */
#define LIFTSPEED 1500

/*
    servo width:
        Servo1: Write: 1080ms; Lift Sweep: 724; Lift Number: 924 
        Servo2: 0.65-1.98
        Servo3: 1.1-1.8ms 
*/
/*
    Arduino defines
*/
#define delay(x)                  (wait_ms(x))
#define delayMicroseconds(x)      (wait_us(x))
#define M_PI                      3.141592653589793238462643  //line 70 math.h
//#include <Time.h>   don't need this RTC clock does it
//#include <Servo.h>  only using one function, writeMicroseconds(), can be done using period_us() on a PwmOut pin


void number( float bx, float by, int num, float scale ) ;
void lift( char lift ) ;
void bogenUZS( float bx, float by, float radius, int start, int ende, float sqee );
void bogenGZS( float bx, float by, float radius, int start, int ende, float sqee );
void drawTo(double pX, double pY);
double return_angle( double a, double b, double c );
void set_XY( double Tx, double Ty );
int minute( void );
int hour( void );

int servoLift = 1500;

PwmOut servo1(p21);  //   lifting servo
PwmOut servo2(p22);  //  left servo
PwmOut servo3(p23);  //  right servo

int val;    // variable to read the value from the analog pin 

volatile double lastX = 75;
volatile double lastY = 47.5;

int last_min = 0;


void setup() 
{ 
  // Set current time
  set_time( (( 2014/*year*/ - 1970) * 31556926 ) 
             + (  3/*month*/ * 2629743 ) 
             + (  6/*day*/ * 86400 )
             + ( 17/*hour*/ * 3600 )
             + (  0/*minute*/ * 60 )
             +    0/*second*/ );  
  drawTo(75, 44);
  lift(0);
  /* replace pin assignments with PWM period  */
 
    servo1.period(0.002);  // this is the PWM period used by the Arduino servo library
    delay(1000);
} 

void loop() 
{  
    //servo2.period_us(M_PI *SERVOFAKTOR + SERVOLEFTNULL); // was writeMicroseconds 
#ifdef CALIBRATION

    // Servohorns will have 90° between movements, parallel to x and y axis
    drawTo(-3, 29.2);
    delay(500);
    drawTo(74.1, 28);
    delay(500);

#else 

  
    int i = 0;
    if (last_min != minute()) {
    /* Assuming these are to save power - removed for first run of port */
    //if (!servo1.attached()) servo1.attach(SERVOPINLIFT);
    //if (!servo2.attached()) servo2.attach(SERVOPINLEFT);
    //if (!servo3.attached()) servo3.attach(SERVOPINRIGHT);
    
    lift(0);

   // hour();
    while ((i+1)*10 <= hour())
    {
      i++;
    }

    number(3, 3, 111, 1);
    number(5, 25, i, 0.9);
    number(19, 25, (hour()-i*10), 0.9);
    number(28, 25, 11, 0.9);

    i=0;
    while ((i+1)*10 <= minute())
    {
      i++;
    }
    number(34, 25, i, 0.9);
    number(48, 25, (minute()-i*10), 0.9);
    lift(2);
    drawTo(75, 47.5);
    lift(1);
    last_min = minute();
    
    //servo1.detach();
    //servo2.detach();
    //servo3.detach();
  }
#endif
} 

int minute( void )
{
    int minutes = 0;
    time_t seconds = time(NULL)+ 19800; 
    minutes = seconds / 60;
    return ( minutes % 60 );
}

int hour( void )
{
    int hour = 0;
    time_t seconds = time(NULL)+ 19800; 
    hour = seconds / 3600;
    return ( hour % 24 );
}


// Writing numeral with bx by being the bottom left originpoint. Scale 1 equals a 20 mm high font.
// The structure follows this principle: move to first startpoint of the numeral, lift down, draw numeral, lift up
void number(float bx, float by, int num, float scale) {

  switch (num) {

  case 0:
    drawTo(bx + 12 * scale, by + 6 * scale);
    lift(0);
    bogenGZS(bx + 7 * scale, by + 10 * scale, 10 * scale, -0.8, 6.7, 0.5);
    lift(1);
    break;
  case 1:

    drawTo(bx + 3 * scale, by + 15 * scale);
    lift(0);
    drawTo(bx + 10 * scale, by + 20 * scale);
    drawTo(bx + 10 * scale, by + 0 * scale);
    lift(1);
    break;
  case 2:
    drawTo(bx + 2 * scale, by + 12 * scale);
    lift(0);
    bogenUZS(bx + 8 * scale, by + 14 * scale, 6 * scale, 3, -0.8, 1);
    drawTo(bx + 1 * scale, by + 0 * scale);
    drawTo(bx + 12 * scale, by + 0 * scale);
    lift(1);
    break;
  case 3:
    drawTo(bx + 2 * scale, by + 17 * scale);
    lift(0);
    bogenUZS(bx + 5 * scale, by + 15 * scale, 5 * scale, 3, -2, 1);
    bogenUZS(bx + 5 * scale, by + 5 * scale, 5 * scale, 1.57, -3, 1);
    lift(1);
    break;
  case 4:
    drawTo(bx + 10 * scale, by + 0 * scale);
    lift(0);
    drawTo(bx + 10 * scale, by + 20 * scale);
    drawTo(bx + 2 * scale, by + 6 * scale);
    drawTo(bx + 12 * scale, by + 6 * scale);
    lift(1);
    break;
  case 5:
    drawTo(bx + 2 * scale, by + 5 * scale);
    lift(0);
    bogenGZS(bx + 5 * scale, by + 6 * scale, 6 * scale, -2.5, 2, 1);
    drawTo(bx + 5 * scale, by + 20 * scale);
    drawTo(bx + 12 * scale, by + 20 * scale);
    lift(1);
    break;
  case 6:
    drawTo(bx + 2 * scale, by + 10 * scale);
    lift(0);
    bogenUZS(bx + 7 * scale, by + 6 * scale, 6 * scale, 2, -4.4, 1);
    drawTo(bx + 11 * scale, by + 20 * scale);
    lift(1);
    break;
  case 7:
    drawTo(bx + 2 * scale, by + 20 * scale);
    lift(0);
    drawTo(bx + 12 * scale, by + 20 * scale);
    drawTo(bx + 2 * scale, by + 0);
    lift(1);
    break;
  case 8:
    drawTo(bx + 5 * scale, by + 10 * scale);
    lift(0);
    bogenUZS(bx + 5 * scale, by + 15 * scale, 5 * scale, 4.7, -1.6, 1);
    bogenGZS(bx + 5 * scale, by + 5 * scale, 5 * scale, -4.7, 2, 1);
    lift(1);
    break;

  case 9:
    drawTo(bx + 9 * scale, by + 11 * scale);
    lift(0);
    bogenUZS(bx + 7 * scale, by + 15 * scale, 5 * scale, 4, -0.5, 1);
    drawTo(bx + 5 * scale, by + 0);
    lift(1);
    break;

  case 111:
    lift(0);
    drawTo(70, 46);
    drawTo(65, 43);

    drawTo(65, 49);
    drawTo(5, 49);
    drawTo(5, 45);
    drawTo(65, 45);
    drawTo(65, 40);

    drawTo(5, 40);
    drawTo(5, 35);
    drawTo(65, 35);
    drawTo(65, 30);

    drawTo(5, 30);
    drawTo(5, 25);
    drawTo(65, 25);
    drawTo(65, 20);

    drawTo(5, 20);
    drawTo(60, 44);
    drawTo(77, 44);
    drawTo(75.2, 47);
    lift(2);

    break;

  case 11:
    drawTo(bx + 5 * scale, by + 15 * scale);
    lift(0);
    bogenGZS(bx + 5 * scale, by + 15 * scale, 0.1 * scale, 1, -1, 1);
    lift(1);
    drawTo(bx + 5 * scale, by + 5 * scale);
    lift(0);
    bogenGZS(bx + 5 * scale, by + 5 * scale, 0.1 * scale, 1, -1, 1);
    lift(1);
    break;

  }
}



void lift(char lift) {
  switch (lift) {
        // room to optimise  !

  case 0: //850

      if (servoLift >= LIFT0) {
      while (servoLift >= LIFT0) 
      {
        servoLift--;
        servo1.period_us(servoLift);                
        delayMicroseconds(LIFTSPEED);
      }
    } 
    else {
      while (servoLift <= LIFT0) {
        servoLift++;
        servo1.period_us(servoLift);
        delayMicroseconds(LIFTSPEED);

      }

    }

    break;

  case 1: //150

    if (servoLift >= LIFT1) {
      while (servoLift >= LIFT1) {
        servoLift--;
        servo1.period_us(servoLift);
        delayMicroseconds(LIFTSPEED);

      }
    } 
    else {
      while (servoLift <= LIFT1) {
        servoLift++;
        servo1.period_us(servoLift);
        delayMicroseconds(LIFTSPEED);
      }

    }

    break;

  case 2:

    if (servoLift >= LIFT2) {
      while (servoLift >= LIFT2) {
        servoLift--;
        servo1.period_us(servoLift);
        delayMicroseconds(LIFTSPEED);
      }
    } 
    else {
      while (servoLift <= LIFT2) {
        servoLift++;
        servo1.period_us(servoLift);                
        delayMicroseconds(LIFTSPEED);
      }
    }
    break;
  }
}


void bogenUZS(float bx, float by, float radius, int start, int ende, float sqee) {
  float inkr = -0.05;
  float count = 0;

  do {
    drawTo(sqee * radius * cos(start + count) + bx,
    radius * sin(start + count) + by);
    count += inkr;
  } 
  while ((start + count) > ende);

}

void bogenGZS(float bx, float by, float radius, int start, int ende, float sqee) {
  float inkr = 0.05;
  float count = 0;

  do {
    drawTo(sqee * radius * cos(start + count) + bx,
    radius * sin(start + count) + by);
    count += inkr;
  } 
  while ((start + count) <= ende);
}


void drawTo(double pX, double pY) {
  double dx, dy, c;
  int i;

  // dx dy of new point
  dx = pX - lastX;
  dy = pY - lastY;
  //path lenght in mm, times 4 equals 4 steps per mm
  c = floor(4 * sqrt(dx * dx + dy * dy));

  if (c < 1) c = 1;

  for (i = 0; i <= c; i++) {
    // draw line point by point
    set_XY(lastX + (i * dx / c), lastY + (i * dy / c));

  }

  lastX = pX;
  lastY = pY;
}

double return_angle(double a, double b, double c) {
  // cosine rule for angle between c and a
  return acos((a * a + c * c - b * b) / (2 * a * c));
}

void set_XY(double Tx, double Ty) 
{
  delay(1);
  double dx, dy, c, a1, a2, Hx, Hy;

  // calculate triangle between pen, servoLeft and arm joint
  // cartesian dx/dy
  dx = Tx - O1X;
  dy = Ty - O1Y;

  // polar lemgth (c) and angle (a1)
  c = sqrt(dx * dx + dy * dy); // 
  a1 = atan2(dy, dx); //
  a2 = return_angle(L1, L2, c);

  servo2.period_us(floor(((a2 + a1 - M_PI) * SERVOFAKTOR) + SERVOLEFTNULL));

  // calculate joinr arm point for triangle of the right servo arm
  a2 = return_angle(L2, L1, c);
  Hx = Tx + L3 * cos((a1 - a2 + 0.621) + M_PI); //36,5°
  Hy = Ty + L3 * sin((a1 - a2 + 0.621) + M_PI);

  // calculate triangle between pen joint, servoRight and arm joint
  dx = Hx - O2X;
  dy = Hy - O2Y;

  c = sqrt(dx * dx + dy * dy);
  a1 = atan2(dy, dx);
  a2 = return_angle(L1, (L2 - L3), c);

  servo3.period_us(floor(((a1 - a2) * SERVOFAKTOR) + SERVORIGHTNULL));
}



int main() {
    setup();
    while(1) {
        loop();
    }
}