//includes
#include "mbed.h"
#include <bitset>

//global variables
int check = 3;

// A class for the key with timer
class Key {
public:
    Key(PinName, unsigned int, PinName);        //constructor
    
private:
    InterruptIn intrpt;                         //interrupt inputpin
    
    DigitalOut led;                             //led for testing Key class
    DigitalOut ledUpdate;                       //led for testing ticker
    
    Ticker t;                                   //timer for sending the code each 100msec
    volatile bool isFirst;                      //bool for checking just pushed or held pushed
    bitset<9> code;                             //9bit code to send status of key
    
    void isPushed(void);                        //function for what to do when key is pushed
    void isReleased(void);                      //function for what to do when key is released
    bool chatRejection(int);                    //function to check if the key is really pushed and no noise
};

Key::Key(PinName pin, unsigned int x, PinName pLed) : intrpt(pin), isFirst(1), code(x), led(pLed), ledUpdate(LED4) {
    intrpt.rise(this, &Key::isPushed);          //add rising edge interrupt
    intrpt.fall(this, &Key::isReleased);        //add falling edge interrupt
}

bool Key::chatRejection(int j) {                //check at least 'j' times pin input to know it's not noise
    for (int i = 0; i < j; ++i) {
        wait(0.01);                             //wait 10ms between each check
        //if (pin != high) return 0;   
    }
    return 1;
}

void Key::isPushed(void) {          
    if (isFirst) {                              //checking if it's just pushed in
        if (chatRejection(check)) {             //checking if it's no noise
            led = 1;                            //sent code
            isFirst = 0;                        //key is being pushed down
        }
    } else {
        ledUpdate = 1;                          //sent other code
        wait(0.2);
        ledUpdate = 0;
    }
    t.attach(this, &Key::isPushed, 0.1);       //set timer to send code each 100msec
}
    
void Key::isReleased(void) {
    isFirst = 1;                                //key is released
    led = 0;                                    //sent code
    t.detach();                                 //kill 100msec timer
}
    

Key left(p36, 2, LED1);                         //make left key at p36
Key center(p35, 1, LED2);                       //make center key at p35
Key right(p34, 3, LED3);                        //make right key at p34

int main() {
    while(1) {
    }
}