basic multithreading

src/main/java/ProgressMonitor.java

@@ -6,17 +6,21 @@ public class ProgressMonitor implements Runnable {
     private final int totalSizeMB;
     private final List<ChunkStatus> chunks;
     private final long monitorDelayMs;
+    private double previousTotalDownloadedMB;
+    private long previousTimeMs;
+
 
     public ProgressMonitor(DownloadConfig config, List<ChunkStatus> chunks) {
         this.fileName = config.getFileName();
         this.totalSizeMB = config.getTotalSizeMB();
         this.chunks = chunks;
         this.monitorDelayMs = 500;
+        this.previousTotalDownloadedMB = 0.0;
+        this.previousTimeMs = System.currentTimeMillis();
     }
 
     @Override
     public void run() {
-        // TODO:
         // Repeatedly check chunk progress until all chunks are completed.
         // In each loop:
         // 1. Read the downloaded size from every chunk
@@ -24,9 +28,7 @@ public class ProgressMonitor implements Runnable {
         // 3. Count completed chunks
         // 4. Print a progress message
         // 5. If completedChunks == chunks.size(), print a final monitor message and stop
-        // 6. Otherwise sleep for monitorDelayMs and continue
-
-
+        // 6. Otherwise, sleep for monitorDelayMs and continue
         while (true) {
             double totalDownloadedMB = 0.0;
             int completedChunks = 0;
@@ -44,19 +46,56 @@ public class ProgressMonitor implements Runnable {
                 percent = (totalDownloadedMB * 100.0) / totalSizeMB;
             }
 
+            long currentTimeMs = System.currentTimeMillis();
+            long timeDiffMs = currentTimeMs - previousTimeMs;
+            double downloadedDiff = totalDownloadedMB - previousTotalDownloadedMB;
+
+            double speedMBps = 0.0;
+            if (timeDiffMs > 0){
+                speedMBps = (downloadedDiff * 1000.0) / timeDiffMs;
+            }
+
+            double etaSeconds = 0.0;
+            if (speedMBps > 0 && totalDownloadedMB < totalSizeMB){
+                double remainingMB =totalSizeMB - totalDownloadedMB;
+                etaSeconds = remainingMB / speedMBps;
+            }
+
+            previousTotalDownloadedMB = totalDownloadedMB;
+            previousTimeMs = currentTimeMs;
+
+
+            int barWidth = 50;
+            int filledWidth = (int)(barWidth * percent / 100.0);
+
+            System.out.print("[");
+            for (int i = 0; i < barWidth; i++) {
+                if (i < filledWidth){
+                    System.out.print("=");
+                }else if (i == filledWidth && percent< 100){
+                    System.out.print(">");
+                }else {
+                    System.out.print(" ");
+                }
+            }
+            System.out.print("]");
+
             System.out.printf(
-                    "Progress for %s: %.1f/%.1f MB (%.2f%%), completed chunks: %d/%d%n",
+                    "Progress for %s: %.1f/%.1f MB (%.2f%%), completed chunks: %d/%d%n , ETA: %s",
                     fileName,
                     totalDownloadedMB,
                     (double) totalSizeMB,
                     percent,
                     completedChunks,
-                    chunks.size()
+                    chunks.size(),
+                    speedMBps,
+                    formatETA(etaSeconds)
             );
 
-
-            // TODO:
-            // If all chunks are completed, print a final message and exit the loop
+            if (completedChunks == chunks.size()){
+                System.out.println("All chunks have been downloaded successfully!");
+                break;
+            }
 
             try {
                 Thread.sleep(monitorDelayMs);
@@ -66,4 +105,20 @@ public class ProgressMonitor implements Runnable {
             }
         }
     }
+    private String formatETA(double etaSeconds){
+        if (etaSeconds <= 0){
+            return "Calculating ...";
+        }
+        int hours = (int)(etaSeconds/3600);
+        int minutes = (int)((etaSeconds%3600)/60);
+        int secondes = (int)(etaSeconds %60);
+
+        if (hours > 0){
+            return String.format("%dh %dm %ds" , hours, minutes, secondes);
+        }else if(minutes > 0){
+            return String.format("%dm %ds" , minutes, secondes);
+        }else{
+            return String.format("%ds", secondes);
+        }
+    }
 }