New model manager implementation pt. 2

Author: niedev

app/src/main/java/nie/translator/rtranslator/Global.java

@@ -111,10 +111,6 @@ public void onCreate() {
         super.onCreate();
         mainHandler = new Handler(Looper.getMainLooper());
         recentPeersDataManager = new RecentPeersDataManager(this);
-        PRDownloaderConfig config = PRDownloaderConfig.newBuilder()
-                .setDatabaseEnabled(false)
-                .build();
-        PRDownloader.initialize(getApplicationContext(), config);
         //initializeBluetoothCommunicator();
         getMicSensitivity();
         createNotificationChannel();
@@ -742,25 +738,59 @@ private void createNotificationChannel(){
     /**
      * Returns the total RAM size of the device in MB
      */
-    public long getTotalRamSize(){
+    public int getTotalRamSize(){
         ActivityManager actManager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
         ActivityManager.MemoryInfo memInfo = new ActivityManager.MemoryInfo();
         actManager.getMemoryInfo(memInfo);
         long totalMemory = memInfo.totalMem / 1000000L;
         android.util.Log.i("memory", "Total memory: " + totalMemory);
-        return totalMemory;
+        return (int) totalMemory;
     }
 
     /**
      * Returns the available RAM size of the device in MB
      */
-    public long getAvailableRamSize(){
+    public int getAvailableRamSize(){
         ActivityManager actManager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
         ActivityManager.MemoryInfo memInfo = new ActivityManager.MemoryInfo();
         actManager.getMemoryInfo(memInfo);
-        long totalMemory = memInfo.availMem;
-        android.util.Log.i("memory", "Total memory: " + totalMemory);
-        return totalMemory / 1000000L;
+        long availableMemory = memInfo.availMem;
+        android.util.Log.i("memory", "Total memory: " + availableMemory);
+        return (int) (availableMemory / 1000000);
+    }
+
+    /**
+     * Returns (in MB) the absolute maximum native RAM allocatable by forcing the OS
+     * to kill all other killable processes.
+     */
+    public int getMaxAllocatableRAM() {
+        ActivityManager activityManager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
+        if (activityManager == null) return 0;
+
+        ActivityManager.MemoryInfo memoryInfo = new ActivityManager.MemoryInfo();
+        activityManager.getMemoryInfo(memoryInfo);
+
+        // Total physical RAM available to the OS (already excludes GPU-reserved RAM)
+        long totalRam = memoryInfo.totalMem;
+
+        // Android doesn't have an API that shows the max amount of RAM available for native allocations before a crash occurs,
+        // so the best way (also hinted here https://developer.android.com/games/optimize/memory-allocation#conservative-memory-budgets)
+        // is to use a percentage of the total RAM between 50% and 25% as a hard limit of native RAM usage for a single app.
+        double maxPercentage = 0.45;
+
+        // The absolute theoretical maximum you can allocate before the OS targets YOU
+        long maxAllocatable = (long) (totalRam - (totalRam*maxPercentage)) / 1000000L;
+
+        // Return the result, ensuring we don't return a negative number on heavily constrained devices
+        return (int) Math.max(0, maxAllocatable);
+    }
+
+    public int getRamThreshold(){
+        ActivityManager actManager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
+        ActivityManager.MemoryInfo memInfo = new ActivityManager.MemoryInfo();
+        actManager.getMemoryInfo(memInfo);
+        long threshold = memInfo.threshold;
+        return (int) (threshold / 1000000);
     }
 
     /**

app/src/main/java/nie/translator/rtranslator/access/DownloadFragment.java

@@ -32,7 +32,6 @@
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.ImageButton;
-import android.widget.ProgressBar;
 import android.widget.TextView;
 
 import com.google.android.material.progressindicator.LinearProgressIndicator;
@@ -122,7 +121,7 @@ public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceStat
         downloadErrorText = view.findViewById(R.id.text_error_download);
         transferErrorText = view.findViewById(R.id.text_error_transfer);
         storageWarningText = view.findViewById(R.id.text_error_storage);
-        progressBar = view.findViewById(R.id.progressBar);
+        progressBar = view.findViewById(R.id.barRam);
         progressDescriptionText = view.findViewById(R.id.progress_description);
         pauseButton = view.findViewById(R.id.pauseButton);
         pauseButton.setTag("iconCancel");

app/src/main/java/nie/translator/rtranslator/access/DownloadFragment2.java

@@ -87,7 +87,7 @@ public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceStat
         downloadErrorText = view.findViewById(R.id.text_error_download);
         transferErrorText = view.findViewById(R.id.text_error_transfer);
         storageWarningText = view.findViewById(R.id.text_error_storage);
-        progressBar = view.findViewById(R.id.progressBar);
+        progressBar = view.findViewById(R.id.barRam);
         progressDescriptionText = view.findViewById(R.id.progress_description);
         pauseButton = view.findViewById(R.id.pauseButton);
         pauseButton.setTag("iconCancel");
@@ -205,7 +205,7 @@ public void onClick(View v) {
             public void onClick(View v) {
                 if(pauseButton.getTag().equals("iconCancel")){
                     //we pause the download
-                    boolean success = downloader.stopAllDownloads();
+                    boolean success = downloader.pauseAllDownloads();
                     if(success) {
                         //we change the icon and tag
                         pauseButton.setImageResource(R.drawable.play_icon);
@@ -242,9 +242,6 @@ public void onStart() {
             final DownloadManager.Callback callback = new DownloadManager.Callback() {
                 public void onServiceConnected(){
                     ArrayList<DownloadGroupInfo> downloadStatus = downloader.getDownloadsStatus();
-                    // we eventually start the download if it is the first time
-                    DownloadGroupInfo downloadGroupInfo = new DownloadGroupInfo(DOWNLOAD_INFOS);
-                    if(downloadStatus == null || !downloadStatus.contains(downloadGroupInfo)) downloader.startDownload(downloadGroupInfo);
                     // we change the GUI based on current download status
                     if(downloadStatus != null){
                         int index = downloadStatus.indexOf(DOWNLOAD_INFOS);
@@ -306,6 +303,11 @@ public void onError(DownloadGroupInfo downloadGroup, DownloadInfo download, int
             };
 
             downloader.subscribeAndResumeDownload(callback);
+            ArrayList<DownloadGroupInfo> downloadStatus = downloader.getSavedDownloadStatus();
+            // we eventually start the download if it is the first time
+            DownloadGroupInfo downloadGroupInfo = new DownloadGroupInfo(DOWNLOAD_INFOS);
+            if(downloadStatus == null || !downloadStatus.contains(downloadGroupInfo)) downloader.startDownload(downloadGroupInfo);
+
         }
     }
 

app/src/main/java/nie/translator/rtranslator/downloader2/DownloadGroupInfo.java

@@ -14,7 +14,8 @@
 import nie.translator.rtranslator.bluetooth.Peer;
 
 public class DownloadGroupInfo implements Parcelable{
-    public DownloadInfoExtended[] downloadsInfo;
+    @NonNull
+    public final DownloadInfoExtended[] downloadsInfo;
     public int runningDownloadIndex = -1;
     private int currentProgress = -1;
     private boolean allDownloadCompleted = false;

app/src/main/java/nie/translator/rtranslator/downloader2/DownloadManager.java

@@ -67,7 +67,7 @@ public void onError(DownloadGroupInfo downloadGroup, DownloadInfo download, int
     public void subscribeAndResumeDownload(@Nullable Callback callback) {
         if(this.callback == null) {
             this.callback = callback;
-            boolean shouldStartService = areDownloadsRunning(false);
+            boolean shouldStartService = areDownloadsRunning(true);
             if(shouldStartService) {
                 startAndBindService();
             }
@@ -79,7 +79,10 @@ public void unsubscribe() {
             if (downloaderService != null) {
                 downloaderService.unregisterClient(serviceCallback);
             }
-            context.unbindService(this);
+            boolean shouldStopService = !areDownloadsRunning(false);
+            if(shouldStopService) {
+                stopAndUnbindService();
+            }
             this.callback = null;
         }
     }
@@ -95,7 +98,7 @@ public void startDownload(DownloadGroupInfo downloadGroup){
         }
     }
 
-    public boolean stopDownload(DownloadGroupInfo downloadGroup){
+    public boolean pauseDownload(DownloadGroupInfo downloadGroup){
         if(downloaderService != null) {
             downloaderService.pauseDownload(downloadGroup);
             return true;
@@ -124,7 +127,7 @@ public boolean startAllDownloads() {
         return false;
     }
 
-    public boolean stopAllDownloads() {
+    public boolean pauseAllDownloads() {
         if(downloaderService != null) {
             downloaderService.pauseAllDownloads();
             return true;
@@ -156,6 +159,14 @@ private void startAndBindService(){
         Log.d("bind download", result ? "success" : "failed");
     }
 
+    private void stopAndUnbindService(){
+        //we unbind from the service
+        context.unbindService(this);
+        // stop the service
+        final Intent intent = new Intent(context, DownloaderService.class);
+        context.stopService(intent);
+    }
+
     private boolean areDownloadsRunning(boolean includePaused){
         SharedPreferences sharedPreferences = context.getSharedPreferences("default", Context.MODE_PRIVATE);
         String downloadsStatusString = sharedPreferences.getString("downloadsStatus", "");
@@ -174,6 +185,17 @@ private boolean areDownloadsRunning(boolean includePaused){
         return false;
     }
 
+    public ArrayList<DownloadGroupInfo> getSavedDownloadStatus(){
+        SharedPreferences sharedPreferences = context.getSharedPreferences("default", Context.MODE_PRIVATE);
+        String downloadsStatusString = sharedPreferences.getString("downloadsStatus", "");
+        if (!downloadsStatusString.isEmpty()) {
+            //we check if there are unfinished downloads that are not paused (or also paused ones if includePaused is true)
+            Gson gson = new Gson();
+            return gson.fromJson(downloadsStatusString, new TypeToken<ArrayList<DownloadGroupInfo>>() {}.getType());
+        }
+        return new ArrayList<>();
+    }
+
     @Override
     public void onServiceConnected(ComponentName componentName, IBinder iBinder) {
         this.downloaderService = ((DownloaderService.LocalBinder) iBinder).getService();

app/src/main/java/nie/translator/rtranslator/downloader2/Downloader2.java

@@ -13,6 +13,7 @@
 import com.downloader.OnStartOrResumeListener;
 import com.downloader.PRDownloader;
 import com.downloader.Progress;
+import com.downloader.Status;
 
 import java.io.BufferedInputStream;
 import java.io.File;
@@ -35,7 +36,6 @@ public class Downloader2 {
     private final DownloadGroupInfo downloadGroupInfo;
     private ClientCallback callback;
     private int lastDownloadSuccessIndex = -1;
-    private boolean allCompleted = false;
 
     public Downloader2(DownloadGroupInfo downloadGroupInfo, Context context, ClientCallback callback) {
         this.downloadGroupInfo = downloadGroupInfo;
@@ -76,8 +76,7 @@ public void startDownloads(){
     public void pauseDownloads(){
         int currentDownloadIndex = downloadGroupInfo.getRunningDownloadIndex();
         if(currentDownloadIndex != -1) {
-            // we cancel the current download (for now this is the best option, it is difficult, if not impossible, to pause without having access to the server)
-            PRDownloader.cancel(downloadGroupInfo.downloadsInfo[currentDownloadIndex].getDownloadId());
+            PRDownloader.pause(downloadGroupInfo.downloadsInfo[currentDownloadIndex].getDownloadId());
             downloadGroupInfo.setRunningDownloadIndex(-1);
         }
     }
@@ -89,7 +88,7 @@ public void cancelDownloads(){
             PRDownloader.cancel(downloadGroupInfo.downloadsInfo[currentDownloadIndex].getDownloadId());
         }
         // we delete the already downloaded files of this group of download
-        for (int i = 0; i <= downloadGroupInfo.downloadsInfo.length; i++){
+        for (int i = 0; i < downloadGroupInfo.downloadsInfo.length; i++){
             File file = new File(downloadGroupInfo.downloadsInfo[i].getDestinationCompletePath());
             if (file.exists()) {
                 file.delete();
@@ -104,7 +103,15 @@ public DownloadGroupInfo getDownloadGroupInfo() {
 
     private void startDownload(int index){
         downloadGroupInfo.setRunningDownloadIndex(index);
-        int downloadId = PRDownloader.download(downloadGroupInfo.downloadsInfo[index].getUrl(), downloadGroupInfo.downloadsInfo[index].getDestinationPath(), downloadGroupInfo.downloadsInfo[index].getName())
+        int downloadId = downloadGroupInfo.downloadsInfo[index].getDownloadId();
+        if(downloadId != -1){
+            if(PRDownloader.getStatus(downloadId) == Status.PAUSED){
+                PRDownloader.resume(downloadId);  //resume if the download was paused during this lifetime of the app
+                return;
+            }
+        }
+        //start the download from scratch or resume it after the app has been restarted
+        downloadId = PRDownloader.download(downloadGroupInfo.downloadsInfo[index].getUrl(), downloadGroupInfo.downloadsInfo[index].getDestinationPath(), downloadGroupInfo.downloadsInfo[index].getName())
                 .build()
                 .setOnStartOrResumeListener(new OnStartOrResumeListener() {
                     @Override
@@ -134,8 +141,8 @@ public void onProgress(Progress progress) {
                         downloadGroupInfo.setCurrentProgress(percentageTotalProgress);
                         if(runningDownloadIndex >= 0) {
                             downloadGroupInfo.downloadsInfo[runningDownloadIndex].setCurrentProgress(percentageProgress);
+                            callback.onProgress(downloadGroupInfo, downloadGroupInfo.downloadsInfo[runningDownloadIndex], percentageTotalProgress, percentageProgress, false, false);
                         }
-                        callback.onProgress(downloadGroupInfo, downloadGroupInfo.downloadsInfo[runningDownloadIndex], percentageTotalProgress, percentageProgress, false, false);
                     }
                 })
                 .start(new OnDownloadListener() {
@@ -226,7 +233,7 @@ private void startNextDownload(){
             startDownload(runningDownloadIndex+1);
         } else {
             //we notify the end of all downloads
-            allCompleted = true;
+            downloadGroupInfo.setAllDownloadCompleted(true);
             callback.onAllCompleted(downloadGroupInfo);
         }
     }
@@ -267,7 +274,7 @@ public boolean equals(@Nullable Object obj) {
         return super.equals(obj);
     }
 
-    private int findFirstIncompletedDownload(){
+    public int findFirstIncompletedDownload(){
         int index = 0;
         for(int i=0; i<downloadGroupInfo.downloadsInfo.length; i++){
             if(downloadGroupInfo.downloadsInfo[i].isAllCompleted()){