Smooth download speed and time remaining

web/static/js/app.js

@@ -3,11 +3,12 @@ import { element } from "./dom.js";
 import { destinationSelect, setAutoExtractDefault, setupDownloadForm, updateSubfolderState } from "./download-form.js";
 import { formatBytes } from "./format.js";
 import { recentDestinations, renderHistory } from "./history.js";
-import { isActive, matchesFilter, renderJobs, updateSpeeds } from "./jobs.js";
+import { isActive, matchesFilter, renderJobs } from "./jobs.js";
 import { fillLibrarySelect } from "./libraries.js";
 import { setupLogin } from "./login.js";
 import { collectTransitions, notifyTransitions } from "./notify.js";
 import { loadSettings, openSettings, setupSettings } from "./settings.js";
+import { updateSpeeds } from "./speed.js";
 import { renderTree, topLevelSelection } from "./tree.js";
 
 const pollIntervalMs = 1500;

web/static/js/format.js

@@ -22,14 +22,24 @@ export function formatBytes(bytes) {
   return `${value.toFixed(unitIndex === 0 ? 0 : 1)} ${units[unitIndex]}`;
 }
 
-export function formatDuration(seconds) {
-  const total = Math.max(0, Math.round(seconds));
-  const hours = Math.floor(total / 3600);
-  const minutes = Math.floor((total % 3600) / 60);
-  const remainingSeconds = total % 60;
-  if (hours > 0) return `${hours}h ${minutes}m`;
-  if (minutes > 0) return `${minutes}m ${remainingSeconds}s`;
-  return `${remainingSeconds}s`;
+function roundTo(value, step) {
+  return Math.max(step, Math.round(value / step) * step);
+}
+
+export function formatRemaining(seconds) {
+  if (!Number.isFinite(seconds) || seconds <= 0) return "almost done";
+  if (seconds < 60) return `${roundTo(seconds, 5)}s`;
+  if (seconds < 600) {
+    const rounded = roundTo(seconds, 15);
+    const minutes = Math.floor(rounded / 60);
+    const remainingSeconds = rounded % 60;
+    return remainingSeconds === 0 ? `${minutes}m` : `${minutes}m ${remainingSeconds}s`;
+  }
+  if (seconds < 3600) return `${roundTo(seconds / 60, 1)}m`;
+  const totalMinutes = roundTo(seconds / 60, 5);
+  const hours = Math.floor(totalMinutes / 60);
+  const minutes = totalMinutes % 60;
+  return minutes === 0 ? `${hours}h` : `${hours}h ${minutes}m`;
 }
 
 export function formatDate(value) {

web/static/js/jobs.js

@@ -1,10 +1,9 @@
 import { button, element } from "./dom.js";
-import { formatBytes, formatDuration, percentOf, statusLabels } from "./format.js";
+import { formatBytes, formatRemaining, percentOf, statusLabels } from "./format.js";
+import { speedOf } from "./speed.js";
 
 const activeStatuses = new Set(["queued", "downloading", "extracting", "moving"]);
 const pausableStatuses = new Set(["queued", "downloading"]);
-const speedSmoothing = 0.3;
-const speedSamples = new Map();
 
 export function isActive(job) {
   return activeStatuses.has(job.status);
@@ -16,26 +15,6 @@ export function matchesFilter(job, filter) {
   return job.status === filter;
 }
 
-export function updateSpeeds(jobs) {
-  const now = performance.now();
-  const seenIds = new Set();
-
-  for (const job of jobs) {
-    seenIds.add(job.id);
-    const previous = speedSamples.get(job.id);
-    let speed = 0;
-    if (previous && job.bytesDone >= previous.bytes && now > previous.time) {
-      const instantSpeed = ((job.bytesDone - previous.bytes) * 1000) / (now - previous.time);
-      speed = previous.speed > 0 ? previous.speed + speedSmoothing * (instantSpeed - previous.speed) : instantSpeed;
-    }
-    speedSamples.set(job.id, { bytes: job.bytesDone, time: now, speed });
-  }
-
-  for (const id of speedSamples.keys()) {
-    if (!seenIds.has(id)) speedSamples.delete(id);
-  }
-}
-
 function displayRank(job) {
   if (isActive(job) && !job.queuePosition) return 0;
   if (job.queuePosition) return 1;
@@ -110,11 +89,11 @@ function progressText(job, percent) {
   }
   if (percent !== null) parts.push(`${percent.toFixed(1)}%`);
 
-  const sample = speedSamples.get(job.id);
-  if (isActive(job) && sample && sample.speed > 0) {
-    parts.push(`${formatBytes(sample.speed)}/s`);
+  const speed = speedOf(job.id);
+  if (isActive(job) && speed > 0) {
+    parts.push(`${formatBytes(speed)}/s`);
     if (job.bytesTotal > job.bytesDone) {
-      parts.push(`${formatDuration((job.bytesTotal - job.bytesDone) / sample.speed)} left`);
+      parts.push(`${formatRemaining((job.bytesTotal - job.bytesDone) / speed)} left`);
     }
   }
   return parts.join("  |  ");

web/static/js/speed.js

@@ -0,0 +1,39 @@
+const windowMs = 30000;
+const minimumSpanMs = 4000;
+const samplesByJob = new Map();
+
+export function updateSpeeds(jobs) {
+  const now = performance.now();
+  const seenIds = new Set();
+
+  for (const job of jobs) {
+    seenIds.add(job.id);
+    let samples = samplesByJob.get(job.id) || [];
+    const last = samples[samples.length - 1];
+    const progressWentBack = last && job.bytesDone < last.bytes;
+    const notTransferring = job.status !== "downloading" && job.status !== "extracting" && job.status !== "moving";
+    if (progressWentBack || notTransferring || (last && last.status !== job.status)) {
+      samples = [];
+    }
+
+    samples.push({ bytes: job.bytesDone, time: now, status: job.status });
+    while (samples.length > 2 && now - samples[1].time >= windowMs) {
+      samples.shift();
+    }
+    samplesByJob.set(job.id, samples);
+  }
+
+  for (const id of samplesByJob.keys()) {
+    if (!seenIds.has(id)) samplesByJob.delete(id);
+  }
+}
+
+export function speedOf(jobId) {
+  const samples = samplesByJob.get(jobId);
+  if (!samples || samples.length < 2) return 0;
+  const first = samples[0];
+  const last = samples[samples.length - 1];
+  const spanMs = last.time - first.time;
+  if (spanMs < minimumSpanMs) return 0;
+  return ((last.bytes - first.bytes) * 1000) / spanMs;
+}