/*
    Over complicated desk LED dimmer
    2016-01-10 Dobrica Pavlinusic <dpavlin@rot13.org>
*/

#include <EEPROM.h>

const int led_pin = 13;
const int buzzer_pin = 4;
const int mosfet_pins[] = { 9, 10, 6 }; // PWM pins: 3,5,6,9,10,11
const int ldr_pin = A3; // LDR +5 -- A3 -[10K]- GND
const int pir_pin = A2;


#define TOUCHPAD 1 // set this to 0 if debugging without touchpad

int LDR_SIZE = 1;	// 1 number of LDR reading to average
int LDR_NOISE = 6;	// 6 calibrate LDR noise level 
int LDR_CHANGE = 1;	// do we report LDR changes?

#define PIR_TIMEOUT 10 // s

#if TOUCHPAD
#include <ps2.h>
PS2 mouse(8, 7); // PS2 synaptics clock, data
#endif
#define TP_LANDSCAPE 0


int mosfet_pwm[] = { 1, 1, 1 }; // initial and current state of mosfet pwm

void MOSFET_PWM(int i, int pwm) {
        analogWrite(mosfet_pins[i], pwm);
	Serial.print("MOSFET=");
	Serial.print(i);
	Serial.print(":");
	Serial.println(pwm);
}


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

  pinMode(led_pin, OUTPUT);
  digitalWrite(led_pin, HIGH); // signal reset

  pinMode(buzzer_pin, OUTPUT);

  for(int i=0; i<=2; i++) {
    pinMode(mosfet_pins[i], OUTPUT);
    analogWrite(mosfet_pins[i], 0);
  }

  pinMode(ldr_pin, INPUT);

  pinMode(pir_pin, INPUT);

#if TOUCHPAD
  Serial.println("Synaptics touchpad init");

  mouse.write(0xff);  // reset
  mouse.read();  // ack byte
  mouse.read();  // blank */

  mouse.read();  // blank */
  mouse.write(0xf0);  // remote mode -- send motion data only on $EB (read data) command
  mouse.read();  // ack
  delayMicroseconds(100);
  mouse.write(0xe8); // set resolution
  mouse.read();  // ack byte
  mouse.write(0x03); // rr  ( rr * 64  +  ss * 16  +  tt * 4  +  uu  == modebyte )
  mouse.read();  // ack byte
  mouse.write(0xe8);
  mouse.read();  // ack byte
  mouse.write(0x00); // ss
  mouse.read();  // ack byte
  mouse.write(0xe8);
  mouse.read();  // ack byte
  mouse.write(0x01); // tt
  mouse.read();  // ack byte
  mouse.write(0xe8);
  mouse.read();  // ack byte
  mouse.write(0x00); // uu
  mouse.read();  // ack byte
  mouse.write(0xf3); // set samplerate 20 (stores mode) 
  mouse.read();  // ack byte
  mouse.write(0x14);
  mouse.read();  // ack byte
  delayMicroseconds(100); 

#endif

  Serial.print("Commands: b - beep, qwe/asd/zxc - MOSFETs, hjkl - single step fade, ui/op/[/] - LDR size-+/noise-+/read/changes, P - PIR\nLDR = ");
  int ldr = analogRead(ldr_pin);
  Serial.println(ldr);

  for(int i=0; i<=2; i++) {
    analogWrite(mosfet_pins[i], 1);
    delay(100);
    int ldr = analogRead(ldr_pin);
    Serial.println(ldr);
    analogWrite(mosfet_pins[i], 0);
  }

  // recall startup values
  for(int i=0; i<=2; i++) {
    int pwm = EEPROM.read(i);
    mosfet_pwm[i] = pwm;
    analogWrite(mosfet_pins[i], pwm);
  }

  digitalWrite(led_pin, LOW);

}

void mosfet(int nr, int value) {
  int pwm = mosfet_pwm[nr];
  if ( pwm == value ) {
    Serial.println("ignored");
    return;
  }
  int sleep = 200 / abs(pwm - value); // changes bigger than 200 (on/off) will be instant
  int step = pwm < value ? 1 : -1;
  for(int i=pwm + step; i != value; i += step) {
    //MOSFET_PWM(nr, i);
    analogWrite(mosfet_pins[nr], i);
    delay(sleep);
  }
  MOSFET_PWM(nr, value);
  mosfet_pwm[nr] = value;
}


unsigned int last_cx = 0;
unsigned int last_cy = 0;         

int last_ldr = 0;
static int ldr_sum = 0;
static int ldr_count = 0;

int last_pir = 0;
long int pir_millis = millis();

int vi_nr = 0; // mosfet to fade with vi binadings


void loop() {

#if TOUCHPAD
  byte mstat1;
  byte mstat2;
  byte mxy;
  byte mx;                    //x coordinate
  byte my;                    //y coordinate
  byte mz;                    //z pressure value

  unsigned int cx,cy;

  mouse.write(0xeb); // read data
  mouse.read();
  
  mstat1 = mouse.read();
  mxy = mouse.read();
  mz = mouse.read();
  mstat2 = mouse.read();
  mx = mouse.read();
  my = mouse.read();


  // collect the bits for x and y
  cx = (((mstat2 & 0x10) << 8) | ((mxy & 0x0F) << 8) | mx ); // 1100-5800
  cy = (((mstat2 & 0x20) << 7) | ((mxy & 0xF0) << 4) | my ); // 800-5000

  if ( last_cx != cx || last_cy != cy ) {
    last_cx = cx;
    last_cy = cy;
    Serial.print("X=");
    Serial.print(cx, DEC);
    Serial.print("\tY=");
    Serial.print(cy, DEC);
    Serial.print("\tZ=");
    Serial.print(mz, DEC);
    if ( cx > 1100 && cy > 800 ) {
#if TP_LANDSCAPE
      int nr  = ( cx - 1100 ) / (( 5800 - 1100 ) / 3);
      int pwm = ( cy - 800  ) / (( 5000 - 800  ) / 255);
#else
      int pwm = ( cx - 1100 ) / (( 5800 - 1100 ) / 255);
      int nr  = ( cy - 800  ) / (( 5000 - 800  ) / 4);
      if ( nr > 2 ) nr -= 1;  // 0 [ 1 2 ] 3 -> 0 1 2
#endif
      pwm -= 1; // allow off
      Serial.print("\tmosfet = ");
      Serial.print(nr);
      Serial.print("\tpwm = ");
      Serial.print(pwm);
      if ( nr >= 0 && nr <= 2 && pwm >= 0 && pwm <= 255 ) {
        Serial.println("\tOK");
        MOSFET_PWM(nr, pwm);
        mosfet_pwm[nr] = pwm;
      } else {
        Serial.println("\tIGNORED");
      }
    }
  }
#endif


  int ldr = analogRead(ldr_pin);
  ldr_sum += ldr;
  ldr_count++;
  if ( ldr_count > LDR_SIZE ) {
    ldr = ldr_sum / ldr_count;
    ldr_count = 0;
    ldr_sum = 0;

    if ( abs(ldr-last_ldr) > LDR_NOISE && LDR_CHANGE ) {  
      Serial.print("LDR = ");
      Serial.println(ldr);
      last_ldr = ( last_ldr + ldr ) / 2;
    }
  }


  int pir = digitalRead(pir_pin);
  if ( pir != last_pir) {
    last_pir = pir;
    Serial.print("PIR = ");
    Serial.println(pir);
  }

  long int ms = millis();
  if ( pir == 0 ) {
    if (pir_millis > 0 && ms - pir_millis > PIR_TIMEOUT * 1000 ) {
      Serial.println("PIR timeout, fade-out");
      pir_millis = -1; // mark that we are in timeout
      for(int i=0; i<=2; i++) {
        MOSFET_PWM(i, 0);
      }
    }
  } else {
    if (pir_millis < 0) {
      Serial.println("PIR fade-in after timeout");
      for(int i=0; i<=2; i++) {
        MOSFET_PWM(i, mosfet_pwm[i]);
      }
    }
    pir_millis = ms;
  }


  if (Serial.available()) {
    digitalWrite(led_pin, HIGH);
    int in = Serial.read();
    switch (in) {
      case 'b':
        tone(buzzer_pin, 1800, 100);
        delay(200);
        tone(buzzer_pin, 2200, 100);
        delay(500);
        break;
      case 'q': mosfet(0, 255); break;
      case 'a': mosfet(0, 127); break;
      case 'z': mosfet(0, 0); break;
      case 'w': mosfet(1, 255); break;
      case 's': mosfet(1, 127); break;
      case 'x': mosfet(1, 0); break;
      case 'e': mosfet(2, 255); break;
      case 'd': mosfet(2, 127); break;
      case 'c': mosfet(2, 0); break;

      // vi mappings
      case 'h': vi_nr = ( vi_nr - 1 + 3 ) % 3; Serial.println(vi_nr); break;
      case 'j': mosfet(vi_nr, (mosfet_pwm[vi_nr]-1+255)%255 ); break;
      case 'k': mosfet(vi_nr, (mosfet_pwm[vi_nr]+1)%255 ); break;
      case 'l': vi_nr = ( vi_nr + 1 ) % 3; Serial.println(vi_nr); break;

      // LDR
      case 'u': LDR_SIZE -= 1; Serial.println(LDR_SIZE); break;
      case 'i': LDR_SIZE += 1; Serial.println(LDR_SIZE); break;
      case 'o': LDR_NOISE -= 1; Serial.println(LDR_NOISE); break;
      case 'p': LDR_NOISE += 1; Serial.println(LDR_NOISE); break;
      case '[': Serial.println(ldr); break;
      case ']': LDR_CHANGE = ! LDR_CHANGE; break;

      case 'P': Serial.println(pir); break;

      case 'S':
        for(int i=0; i<3; i++) EEPROM.write(i, mosfet_pwm[i]);
        Serial.println("EEPROM store brightness");
	break;

      /*
              m1 = (m1 + 10) % 255;
              analogWrite(mosfet1_pin, m1);
              Serial.print("MOSFET 1 = ");
              Serial.println(m1);
              break;
            case 'a':
              m1 = (m1 - 10) % 255;
              analogWrite(mosfet1_pin, m1);
              Serial.print("MOSFET 1 = ");
              Serial.println(m1);
              break;
      */
      default:
        Serial.print("unknown command ");
        Serial.println(in);
    }
    digitalWrite(led_pin, LOW);
  }

}