/* Program: Remote Car Start
*/

//EQUATES
//Inputs
int signal_on = 2;  //"ON" signal inputed to pin 2
int oil_sens = 3;   //Vehicle RPM sensor inputted to pin 3
int parking_brake = 4;
int braking_ped = 5;  //Vehicle Brake Pedal inputted to pin 5

//Outputs
int on_ctrl = 11;     //Ignition Control Relay controlled by pin 8
int start_ctrl = 10;  //Start Control Relay controlled by pin 9
int acc_ctrl = 12;   //Accessory Control Relay controlled by pin 11
int flashlights = 9;
unsigned long start_time;  //Variable used to store the time at which the starter is engaged
char data = 0;             //Variable used to store data received via the serial port

int buttonState;
unsigned long timePress = 0;
unsigned long timePressLimit = 0;
int clicks = 0;

//DEFINITIONS
void setup() {
  pinMode(oil_sens, INPUT);
  pinMode(signal_on, INPUT);  //Define pin inputs and outputs
  pinMode(parking_brake, INPUT_PULLUP);
  pinMode(braking_ped, INPUT);
  pinMode(on_ctrl, OUTPUT);
  pinMode(start_ctrl, OUTPUT);
  pinMode(acc_ctrl, OUTPUT);
  pinMode(flashlights, OUTPUT);
  interrupts();
  Serial.begin(9600);  //Initialize the serial port with a baud rate of 9600
}

//PROGRAM

//Loop function: Wait for a START command to be received (command via serial port or
//voltage applied to signal_on pin)
void loop() {
  buttonState = digitalRead(signal_on);
  if (buttonState == HIGH) {
    delay(500);
    Serial.print("Button Pressed: ");
    clicks++;
    Serial.println(clicks);
    if (clicks == 1) {
      timePress = millis();
      timePressLimit = timePress + 3000;
    } else if (clicks == 3 && millis() < timePressLimit) {
      Serial.println("Button Pressed 3 Times: Starting");
      begin();
      timePress = 0;
      timePressLimit = 0;
      clicks = 0;
    }
  }
  if (clicks <= 2 && timePressLimit != 0 && millis() > timePressLimit) {
    Serial.println("Button Pressed 1 or 2 Times");
    timePress = 0;
    timePressLimit = 0;
    clicks = 0;
  } else if (Serial.available() > 0)  //Check if any serial data is available
  {
    data = Serial.read();  //Set "data" variable to currently available serial data
    check();               //Go to "check" funtion if serial data is available
  }
}


//Check function: Test for proper character set from BT
void check() {
  if (data == 's')  //Check if an "s" has been sent
  {
    begin();  //Begin start sequence if "s" has been sent
  } else {
    Serial.println("Invalid Command");  //If anything other than an "s" has been sent, send "Invalid Command" error message
    loop();                             //Return to beginning of program
  }
}

//Begin function: Turn on accessory and ignition
void begin() {
  digitalWrite(flashlights, HIGH);
  delay(300);
  digitalWrite(flashlights, LOW);
  p_brake();  //Go to "p_brake" funciton
}

//parking_brake function: Check if the vehicle is on the parking break position.
// Continue if vehicle is on parking breake. Exit start sequence if vehicle is not on the parking break.
void p_brake() {
  if (digitalRead(parking_brake) == LOW)  //Continue only if vehicle is on parking breake
  {
    start();  //Start vehicle if on parking breake
  } else {
    Serial.println("Vehicle Not on Parking Brake");  //If in gear, send "Vehicle Not on Parking Brake" error message
    vehicle_off();                                   //Exit start sequence if not on the parking break
  }
}

//Start function: Engage starter only if engine is not already running.
void start() {
  digitalWrite(acc_ctrl, HIGH);  //Turn accessory OFF
  delay(1000);
  digitalWrite(on_ctrl, HIGH);
  delay(2000);                     //2 second delay
  if (digitalRead(oil_sens) == HIGH)
  {
    disengage_starter();    //Go to Starter_engaged function
  }
  else
  {
    Serial.println("Oil Light is OFF");
    vehicle_off();
  }
}


//Disengage_starter function: Disengage the starter.
void disengage_starter() {
  digitalWrite(start_ctrl, HIGH);
  delay(500);
  if (digitalRead(oil_sens) == LOW)
  {
    digitalWrite(start_ctrl, LOW);    //Disengage the starter
    Serial.println("Engine Running");
    digitalWrite(flashlights, HIGH);  //Turn flashlights ON
    start_time = millis();
    vehicle_off_sense();  //Go to vehicle_off_sense function
  }
  else {
    vehicle_off();
  }

}



//Vehicle_off_sense function: Waits for an "off" signal to be sent while the engine is running.
//If no "off" signal is received, turns off the vehicle after 10 minutes has elapsed since the engine start.
void vehicle_off_sense() {
  if (digitalRead(braking_ped) == HIGH)  //Check if braking pedal is pushed
  {
    Serial.println("Vehicle OFF -- Braking Pedal Pushed");  //Send "Vehicle OFF -- Braking Pedal Pushed" message if braking pedal pushed
    vehicle_off();                                          //Turn vehicle off if braking pedal pushed
  } else if (start_time + 600000 < millis())                //Check if 10 minutes has elapsed since engine start
  {
    Serial.println("Vehicle OFF -- Automatic Timeout");  //Send "Vehicle OFF -- Automatic Timeout" message if engine has been
    //running for 10 minutes
    vehicle_off();                    //Turn vehicle off if engine is running for 10 minutes
  } else if (Serial.available() > 0)  //Check if a signal has been sent via serial data
  {
    data = Serial.read();  //Store serial sent serial data
    if (data == 'o')       //Check if signal sent is an OFF command ("o")
    {
      Serial.println("Vehicle OFF -- User Commanded");  //Send "Vehicle OFF -- User Commanded" message if serial data is the OFF
      //command ("o")
      vehicle_off();  //Turn vehicle off if OFF command is sent via serial data
    }
  } else if (digitalRead(signal_on) == HIGH)  //Check if OFF command has been sent via BT module
  {
    Serial.println("Vehicle OFF -- User Commanded");  //Send "Vehicle OFF -- User Commanded" message if OFF
    //command was sent
    vehicle_off();  //Turn vehicle off if OFF command was sent via BT module
  } else {
    vehicle_off_sense();  //Repeat this function if none of the above conditions have been met
  }
}

//Vehicle_off function: Turns the vechile off and starts the whole program over
void vehicle_off() {
  Serial.println("Vehicle OFF");
  digitalWrite(on_ctrl, LOW);      //Turn ignition OFF
  digitalWrite(acc_ctrl, LOW);     //Turn accessory OFF
  digitalWrite(start_ctrl, LOW);
  digitalWrite(flashlights, LOW);  //Turn flashlights OFF
  loop();                          //Repeat program (look for start command)\

}