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/*Program Example 9.8: Tests reaction time, and demos use of Timer and Timeout functions
*/
#include "mbed.h"
#include <stdio.h>
#include <stdlib.h> //contains rand() function

void measure ();

Serial pc(USBTX, USBRX);

DigitalOut led1(LED1);
DigitalOut led4(LED4);

DigitalIn responseinput(p5); //the player hits the switch connected here to respond

Timer t; //used to measure the response time

Timeout action; //the Timeout used to initiate the response speed test

int main ()
{
    pc.printf("Reaction Time Test\n\r");
    pc.printf("------------------\n\r");
    while (1) {
        int r_delay; //this will be the “random” delay before the led is blinked
        pc.printf("New Test\n\r");
        led4=1; //warn that test will start
        wait(0.2);
        led4=0;
        r_delay = rand() % 10 + 1; // generates a pseudorandom number range 1-10
        pc.printf("random number is %i\n\r", r_delay); // allows test randomness;
//removed for normal play
        action.attach(&measure,r_delay); // set up Timeout to call measure()
// after random time
        wait(10); //test will start within this time, and we then return to it
    }
}

void measure ()  // called when the led blinks, and measures response time
{
    if (responseinput ==1) { //detect cheating!
        pc.printf("Don’t hold button down!");
    } else {
        t.start(); //start the timer
        led1=1; //blink the led
        wait(0.05);
        led1=0;
        while (responseinput==0) {
//wait here for response
        }
        t.stop(); //stop the timer once response detected
        pc.printf("Your reaction time was %f seconds\n\r", t.read());
        t.reset();
    }
}