init Timer

js/main.js

@@ -0,0 +1,28 @@
+var htmlTimer = document.getElementById("timer");
+
+var timer = setInterval(timerLoop, 1000);
+const queryString = window.location.search;
+const urlParams = new URLSearchParams(queryString);
+let time = parseInt(urlParams.get('time'))
+
+
+function timerLoop() {
+    htmlTimer.innerHTML = convertSecMin(time);
+    time--;
+    if(time < 0) {
+        clearInterval(timer)
+        htmlTimer.style.color = "red";
+    }
+}
+
+function convertSecMin(value) {
+    let seconds = Math.floor(value % 60);
+    let minuts = Math.floor(value / 60);
+    return `${convertDigits(minuts)}:${convertDigits(seconds)}` 
+}
+
+function convertDigits(number) {
+    return number.toLocaleString('en-US', {
+        minimumIntegerDigits : 2,
+        useGrouping : false});
+}

js/timer.js

@@ -0,0 +1,37 @@
+class Timer {
+    
+    /**
+     * Make a timer
+     * @param {int} time in seconds
+     * @throws TypeError if time is not a positive Integer  
+     */
+    constructor(time) {
+        if (!isValid(time)) throw new TypeError(`${time} n'est pas un entier valide`);
+        this.time = time;
+    }
+
+
+    /**
+     * Predicate that show if the value of the timer is correctly set
+     * @param {int} valueTest 
+     * @return True if the predicate is verified
+     *         False else
+     */
+    isValid(valueTest) {
+        return Number.isInteger(valueTest) && valueTest > 0
+    }
+
+    /**
+     * @return the current time
+     */
+    getTime() {
+        return this.time
+    }
+
+    /**
+     * Make start the timer
+     */
+    startTimer() {
+        setTimeout(this.time--, 1000)
+    }
+}