#include <TM1637.h>
//
// This is just some mish-mash of a bunch of things but it's posted for the video over here:
// https://youtu.be/JN4j-aCagH0
//
// How you set the date:
// exec 3<> /dev/ttyUSB0 
// printf "$(date "+obase=16;4096+(%H*60+%M)" | bc | sed -E s'/(..)/\\x\1/g')" > /dev/ttyUSB0
// exec 3<&-

// The wire protocol is 3 bytes
//
// |----|---- ... ---|
//  cmd       args
//
// 0x0 is brightness (4 bits) + clock set (minutes from midnight lsb, 2 bytes)
// 0x1 is time to display message in 100ms chunks (4bits) + 4 digits display

int CLK = 3;
int DIO = 2;
int offset = 0;
int cycle = 0;
int synctime = 0;
int ix = 0;
uint8_t inbuf[3];
TM1637 tm(CLK,DIO);

void setup() {
  tm.init();
  Serial.begin(9600);
  tm.set(7);
}

void displayTime(int minute) {
  displayNumber(100*(minute/60) + minute % 60);
}
static int8_t alphie[] = {
  0x3f,0x06,0x5b,0x4f,
  0x66,0x6d,0x7d,0x07,
  0x7f,0x6f,                         
  //  a     b     c     d     e
      0x77, 0x7C, 0x39, 0x5e, 0x79,
  //  f     g     h     i     j
      0x71, 0x7d, 0x76, 0x30, 0x1e,
  //  k     l     m     n     o
      0x72, 0x38, 0x33, 0x54, 0x5c,
  //  p     q     r     s     t
      0x73, 0x67, 0x50, 0x6d, 0x78,
  //  u     v     w     x     y
      0x3e, 0x2a, 0x62, 0x52, 0x66,
  //  z
      0x1b
};

int8_t shift(int8_t in, int dir) {
  int8_t out = 0;
  static int8_t map[] = {
    0x02, 0x04,
    0x01, 0x40,
    0x20, 0x10,
    0x40, 0x08,    
  };

  int8_t off_1 = dir >= 0 ? 0 : 1;
  int8_t off_2 = dir >= 0 ? 1 : 0;

  for(int s = 0; s < 8; s += 2) {
    out |= ((in & map[s + off_1]) > 0) ? map[s + off_2] : 0;
  }
  return out;
}

void segdo(uint8_t BitAddr,int8_t SegData)
{
  tm.start();          //start signal sent to TM1637 from MCU
  tm.writeByte(ADDR_FIXED);//
  tm.stop();           //
  tm.start();          //
  tm.writeByte(BitAddr|0xc0);//
  tm.writeByte(SegData);//
  tm.stop();            //
  tm.start();          //
  tm.writeByte(tm.Cmd_DispCtrl);//
  tm.stop();           //
}
void word(char toshow[]) {
  for(int ix = 0; ix < 4 && ix < strlen(toshow); ix++) {
    segdo(ix, alphie[toshow[ix] - 'a']);
  }
}


int cycles = 0;
void show(int8_t seg, int8_t what, int dur) {
  for(int iy=dur/5; iy > 0; iy--) {
    segdo(seg, what);        delay(1);
    segdo(seg, 0);  delay(4);
  }
}

void loop() {
/*  for(int i = 0; i < 4; i++) {
    segdo(i,alphie[(i + ix)%26]);
  }*/
  int8_t up1, up2, down1, down2, tens;
  for(int ix = 49; ix > 0; ix--) {
    int8_t ones = ix % 10;
    if(ones == 9) {
      tens = ix / 10 % 10;
    } 
    
    up1 = shift(alphie[ones], -1);
    up2 = shift(up1, -1);
    down1 = shift(alphie[ones], 1);
    down2 = shift(down1, 1);

    cycles ++;
    if(ones == 9) { 
      segdo(0, shift(shift(alphie[tens], -1), -1));
    } 
    segdo(1, up2); delay(150);
    if(ones == 9) {
      segdo(0, shift(alphie[tens], -1));
    }
    segdo(1, up1); delay(200);

    if(ones == 9) {
      segdo(0, alphie[tens]);
    }

    segdo(1, alphie[ones]); delay(300);
    if(ones == 0) {
      segdo(0, shift(alphie[tens], 1));      
    }

    segdo(1, down1);      delay(200);
    if(ones == 0) {
      segdo(0, shift(shift(alphie[tens], 1), 1));      
    }

    segdo(1, down2);      delay(150);//max(1,cycles * 1000 - millis()) );
  }
  /*
  if (Serial.available() > 0){
    Serial.readBytes(inbuf, 10);

    segdo(0, inbuf[0]);
    segdo(1, shift(inbuf[0], 1));
    segdo(2, shift(inbuf[0], -1));
  }    
  
  delay(200);
  ix++;
  /*
  tm.point((ix++)&1);
  displayTime( ((millis()-synctime) / 60000 + offset) % 1440);
  delay(500);
  if (Serial.available() > 0){
    Serial.readBytes(inbuf, 3);
      
    switch(inbuf[0]&0xF0) {
      case 0x00:
        offset = inbuf[2] + (inbuf[1]&0xf)*256;    
        synctime = millis();
        tm.set(inbuf[0]&0xf);
        break;

      case 0x10:
        int duration = (inbuf[0]&0x0f) * 250;
        displayNumber(inbuf[2] + (inbuf[1]&0xf)*256);
        delay(duration);
        break;        
    }

  }
  */
;}

void displayNumber(int num){   
    tm.display(3, num % 10);   
    tm.display(2, num / 10 % 10);   
    tm.display(1, num / 100 % 10);   
    tm.display(0, num / 1000 % 10);
}