Handling 'onkeydown' event

Question

I've added onkeydown event listener to document, and when the event fires, I play an audio file. This audio file is a gun sound. If you tap the key once, it plays fine, but if you press and hold, the audio repeats incredibly fast. I've solved that with a simple playing condition check, but I have another problem. If I press and hold, only after the first shot, it sounds like the gun is firing repeatedly. For example, it goes like ta-tatatatata.

How can I fix my machine gun? Make it fire like tatatata.

Demo

---

var weapons = {
    aug : {
        audio   : "weapons/aug-1.wav",
        icon    : "e",
        key     : "A"
    }
};

function playAudio(file) {
    if (!playing) {
        var audio = new Audio(file);
        audio.play();
        playing = true;
        setTimeout(function() {
            playing = false;
        }, 100);
    }
}

document.onkeydown = function(e) {
    switch(e.keyCode) {
        case 65:
            playAudio(weapons.aug.audio);
            break;
    }
}

Answer 1

I started to code this before thinking about it, and that was my first mistake. I've solved the problem now. All I had to do was simply mimic the FPS games' fire command. Start an interval with the mousedown and clear the interval with mouseup.

Instead of using mouse click, I had to use key press. So when I press a key (and hold), an interval starts and plays the audio repeatedly. When I release the key, interval is cleared, audio stops.

Demo

var weapons = {
    aug : {
        audio       : "weapons/aug-1.wav",
        icon        : "e",
        key         : "A",
        interval    : null,
        firstShot   : false,
    }
};

function playAudio(file, weapon) {
    if (!weapon.interval) {
        if (!weapon.firstShot) {
            var audio = new Audio(file);
            audio.play();
            weapons.aug.firstShot = true;
        }
        weapon.interval = setInterval(function() {
            var audio = new Audio(file);
            audio.play();
        }, 150);
    }
}

document.onkeydown = function(e) {
    switch (e.keyCode) {
        case 65:
            playAudio(weapons.aug.audio, weapons.aug);
            break;
    }
}
document.onkeyup = function(e) {
    switch (e.keyCode) {
        case 65:
            clearInterval(weapons.aug.interval);
            weapons.aug.interval = null;
            weapons.aug.firstShot = false;
            break;
    }
}