// Shane Williams
// July 16, 2017
// Parking Lot Program


#include <Servo.h>  // Arduino Servo Library

Servo exitBar;     // create servo object to control a servo

int ServoM = 12;        // connected to the servo motor
int Bright = 11;        // servo library disable PWM on pins 9 and 10
int Exit = 9;           // pin connected to the Exit button
int In = 8;             // pin connected to the motion detector to update the display

int BarLow = 177;       // lowered position of the bar
int BarUp = 95;         // raised position of the bar
int INTEN = 80;         // led display brightness
int pirState = LOW;     // motion detector starts with no motion detected
int pirVal = 0;         // motion detector pin status
int buttonVal = 0;      // exit button pin status

// Pins conections to segments (cathodes).
int segA = 0;
int segB = 1;
int segC = 2;
int segD = 3;
int segE = 4;
int segF = 5;
int segG = 6;

// Array with the segments to represent the decimal numbers (0-9)
byte segments[10] = {
// each set represents a number on the 7 segment display
  B00111111, // number 0
  B00000110, // number 1
  B01011011, // number 2
  B01001111, // number 3
  B01100110, // number 4
  B01101101, // number 5
  B01111101, // number 6
  B00000111, // number 7
  B01111111, // number 8
  B01101111  // number 9
};

void setup(){
  exitBar.attach(ServoM);       // attaches the servo.

  pinMode(Exit, INPUT);         // set Exit connection to Input
  pinMode(In, INPUT);           // set In connection to Input
  digitalWrite(Exit, HIGH);     // Connect Pull-Up resistor
  digitalWrite(In, HIGH);       // Connect Pull-Up resistor
  pinMode(segA,OUTPUT);
  pinMode(segB,OUTPUT);
  pinMode(segC,OUTPUT);
  pinMode(segD,OUTPUT);
  pinMode(segE,OUTPUT);
  pinMode(segF,OUTPUT);
  pinMode(segG,OUTPUT);
  pinMode(Bright,OUTPUT);
  analogWrite(Bright,255*INTEN/100);
  exitBar.write(BarLow);        // Start with the bar in the low position
//  delay(1000);
}

int  Available = 9;                 // Number of parking spots available

void loop(){
    pirVal = digitalRead(In);   // reads motion detector status
    Display(Available);         // displays number of parking spaces available
    if(pirVal == HIGH) {        // if motion detector status is high(if motion has been triggered)...
        if(Available != 0) {    // if there are still spots available...
        Available--;            // decrease the amount of available spots by 1
        delay(2000);            // wait 2 seconds
        }
     }
    buttonVal = digitalRead(Exit);  // reads exit button status
    if(buttonVal = HIGH) {          // if exit button has been pressed...
        if(Available != 9) {        // if there are less than 9 spots available(9 would mean there is no one in the parking lot to press the button)...
        Available++;                // increase the amount of available spots by 1
        exitBar.write(BarUp);       // raise the flow bar
        delay(3000);                // wait 3 seconds
        exitBar.write(BarLow);      // lower the flow bar
        }
    }
}

// writes a number to the display
void Display(int number){
    byte segs =  ~segments[number];

    digitalWrite(segA, bitRead(segs, 0));
    digitalWrite(segB, bitRead(segs, 1));
    digitalWrite(segC, bitRead(segs, 2));
    digitalWrite(segD, bitRead(segs, 3));
    digitalWrite(segE, bitRead(segs, 4));
    digitalWrite(segF, bitRead(segs, 5));
    digitalWrite(segG, bitRead(segs, 6));
}