timer control

server/timer.js

@@ -1,56 +1,125 @@
 class Timer {
-  constructor(durationInSeconds) {
+  #current = null;
+  #finishAt = null;
+  #startedAt = null;
+  #pausedAt = null;
+  #pausedInterval = null;
+  #pausedTotal = null;
+  state = 'pause';
+
+  constructor() {}
+
+  // call setup separately
+  setupWithSeconds(seconds, autoStart = false) {
+    // aux
     const now = new Date().getTime();
-    this.duration = durationInSeconds;
-    this.current = durationInSeconds;
-    this.finish = new Date().getTime() + durationInSeconds * 1000;
-    this.started = now;
+
+    // populate targets
+    this.#finishAt = now + seconds * 1000;
+
+    // start counting
+    this.#startedAt = now;
+
+    if (autoStart) {
+      this.state = 'start';
+    } else {
+      this.#pausedAt = now;
+      this.#pausedInterval = 0;
+    }
+    this.#pausedTotal = 0;
+    this.update();
   }
 
   // update()
   update() {
-    // doesnt include start time yet
+    // get current time
     const now = new Date().getTime();
-    this.current = (this.finish - now) * 0.001;
+
+    // check playstate
+    switch (this.state) {
+      case 'start':
+        // update current timer
+        this.#current = this.#finishAt + this.#pausedTotal - now;
+        break;
+      case 'pause':
+        // update paused time
+        this.#pausedInterval = now - this.#pausedAt;
+        break;
+      default:
+        console.error('Timer: no playstate on update call', this.state);
+        break;
+    }
+  }
+
+  // helpers
+  static toSeconds(millis) {
+    return Math.floor(Math.max(millis * 0.001), 0);
+  }
+
+  #getExpectedFinish() {
+    return (
+      this.#finishAt +
+      (this.#pausedInterval + this.#pausedTotal)
+    );
   }
 
   // getObject
   getObject() {
     this.update();
     return {
-      duration: this.duration,
-      current: this.current,
-      finish: this.finish,
-      started: this.started,
+      currentSeconds: Timer.toSeconds(this.#current),
+      expectedFinish: this.#getExpectedFinish(),
+      startedAt: this.#startedAt,
     };
   }
 
-  // duration
-  getDuration(durationInSeconds) {
-    return this.duration;
-  }
-  setDuration() {
-    try {
-      this.duration = durationInSeconds;
-      return true;
-    } catch (e) {
-      console.error(e);
-      return false;
-    }
-  }
-
   // current time in seconds
   getCurrentInSeconds() {
     // update timeStamp
     this.update();
-    return this.current;
+    return Timer.toSeconds(this.#current);
   }
 
   // playback
-  start() {}
-  pause() {}
-  // playback
-  stop() {}
+  start() {
+    // do we need to change
+    if (this.state === 'start') return;
+
+    // update start time if needed
+    if (!this.#startedAt) {
+      this.#startedAt = new Date().getTime();
+    }
+
+    // check if there is paused time
+    if (this.#pausedInterval) {
+      this.#pausedTotal += this.#pausedInterval;
+      this.#pausedInterval = null;
+    }
+
+    // change state
+    this.state = 'start';
+    console.log('started');
+  }
+  pause() {
+    // do we need to change
+    if (this.state === 'pause') return;
+
+    // update pause time
+    this.#pausedAt = new Date().getTime();
+
+    // change state
+    this.state = 'pause';
+
+    console.log('paused');
+  }
+  stop() {
+    console.log('stop: not yet implemented');
+    return false;
+  }
+  roll() {
+    console.log('roll: not yet implemented');
+    return false;
+  }
 }
 
 module.exports = Timer;