feat: Implement caching of SHA1's and fall back to old loading bar when offline (#13)

app_pojavlauncher/src/main/java/com/kdt/mcgui/mcAccountSpinner.java

@@ -9,6 +9,7 @@ import android.graphics.Color;
 import android.graphics.Paint;
 import android.graphics.drawable.BitmapDrawable;
 import android.graphics.drawable.Drawable;
+import android.net.NetworkInfo;
 import android.net.Uri;
 import android.util.AttributeSet;
 import android.util.Log;
@@ -276,6 +277,10 @@ public class mcAccountSpinner extends AppCompatSpinner implements AdapterView.On
     }
 
     private void performLogin(MinecraftAccount minecraftAccount){
+        // Logging in when there's no internet is useless. This should really be turned into a network callback though.
+        if(!Tools.isOnline(getContext())){
+            return;
+        }
         if(minecraftAccount.isLocal()) return;
 
         mLoginBarPaint.setColor(getResources().getColor(R.color.minebutton_color));

app_pojavlauncher/src/main/java/net/kdt/pojavlaunch/Tools.java

@@ -21,6 +21,8 @@ import android.content.res.Resources;
 import android.database.Cursor;
 import android.hardware.Sensor;
 import android.hardware.SensorManager;
+import android.net.ConnectivityManager;
+import android.net.NetworkInfo;
 import android.net.Uri;
 import android.os.Build;
 import android.os.Bundle;
@@ -1429,6 +1431,18 @@ public final class Tools {
         OBSOLETE_RESOURCES_PATH = DIR_GAME_NEW + "/resources";
     }
 
+    private static NetworkInfo getActiveNetworkInfo(Context ctx) {
+        ConnectivityManager connMgr = (ConnectivityManager) ctx.getSystemService(Context.CONNECTIVITY_SERVICE);
+        NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
+        return networkInfo; // This can return null when there is no wifi or data connected
+    }
+
+    public static boolean isOnline(Context ctx) {
+        NetworkInfo info = getActiveNetworkInfo(ctx);
+        if(info == null) return false;
+        return (info.isConnected());
+    }
+
     public static boolean isDemoProfile(Context ctx){
         MinecraftAccount currentProfile = PojavProfile.getCurrentProfileContent(ctx, null);
         return currentProfile != null && currentProfile.isDemo();

app_pojavlauncher/src/main/java/net/kdt/pojavlaunch/mirrors/DownloadMirror.java

@@ -76,7 +76,8 @@ public class DownloadMirror {
      * @param urlInput The original (Mojang) URL for the download
      * @return the length of the file denoted by the URL in bytes, or -1 if not available
      */
-    public static long getContentLengthMirrored(int downloadClass, String urlInput) throws IOException {
+    public static long getContentLengthMirrored(int downloadClass, String urlInput){
+        try {
             long length = DownloadUtils.getContentLength(getMirrorMapping(downloadClass, urlInput));
             if (length < 1) {
                 Log.w("DownloadMirror", "Unable to get content length from mirror");
@@ -85,6 +86,9 @@ public class DownloadMirror {
             } else {
                 return length;
             }
+        } catch (IOException ignored) { // If error happens, fallback to old file counter instead of size. This shouldn't really happen unless offline though.
+            return -1L;
+        }
     }
 
     /**

app_pojavlauncher/src/main/java/net/kdt/pojavlaunch/tasks/MinecraftDownloader.java

@@ -3,6 +3,9 @@ package net.kdt.pojavlaunch.tasks;
 import static net.kdt.pojavlaunch.PojavApplication.sExecutorService;
 
 import android.app.Activity;
+import android.content.Context;
+import android.net.ConnectivityManager;
+import android.net.NetworkInfo;
 import android.util.Log;
 
 import androidx.annotation.NonNull;
@@ -25,9 +28,12 @@ import net.kdt.pojavlaunch.value.DependentLibrary;
 import net.kdt.pojavlaunch.value.MinecraftClientInfo;
 import net.kdt.pojavlaunch.value.MinecraftLibraryArtifact;
 
+import java.io.BufferedReader;
 import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileReader;
+import java.io.FileWriter;
 import java.io.IOException;
-import java.net.UnknownHostException;
 import java.util.ArrayList;
 import java.util.Map;
 import java.util.Set;
@@ -56,6 +62,7 @@ public class MinecraftDownloader {
     private static final ThreadLocal<byte[]> sThreadLocalDownloadBuffer = new ThreadLocal<>();
 
     private boolean isLocalProfile = false;
+    private boolean isOnline;
 
     /**
      * Start the game version download process on the global executor service.
@@ -65,11 +72,13 @@ public class MinecraftDownloader {
      * @param listener The download status listener
      */
     public void start(@Nullable Activity activity, @Nullable JMinecraftVersionList.Version version,
-                      @NonNull String realVersion, // this was there for a reason
+                      @NonNull String realVersion,
                       @NonNull AsyncMinecraftDownloader.DoneListener listener) {
         if(activity != null){
             isLocalProfile = Tools.isLocalProfile(activity);
+            isOnline = Tools.isOnline(activity);
             Tools.switchDemo(Tools.isDemoProfile(activity));
+
         } else {
             isLocalProfile = true;
             Tools.switchDemo(true);
@@ -77,14 +86,32 @@ public class MinecraftDownloader {
 
         sExecutorService.execute(() -> {
             try {
-                if(isLocalProfile){
+                if(isLocalProfile || !isOnline) {
-                    throw new RuntimeException("Download failed. Please make sure you are logged in with a Microsoft Account.");
+                    String versionMessage = realVersion; // Use provided version unless we find its a modded instance
+
+                    // See if provided version is a modded version and if that version depends on another jar, check for presence of both jar's .json.
+                    try {
+                        // This reads the .json associated with the provided version. If it fails, we can assume it's not installed.
+                        File providedJsonFile = new File(Tools.DIR_HOME_VERSION + "/" + realVersion + "/" + realVersion + ".json");
+                        JMinecraftVersionList.Version providedJson = Tools.GLOBAL_GSON.fromJson(Tools.read(providedJsonFile.getAbsolutePath()), JMinecraftVersionList.Version.class);
+
+                        // This checks if running modded version that depends on other jars, so we use that for the error message.
+                        File vanillaJsonFile = new File(Tools.DIR_HOME_VERSION + "/" + providedJson.inheritsFrom + "/" + providedJson.inheritsFrom + ".json");
+                        versionMessage = providedJson.inheritsFrom != null ? providedJson.inheritsFrom : versionMessage;
+
+                        // Ensure they're both not some 0 byte corrupted json
+                        if (providedJsonFile.length() == 0 || vanillaJsonFile.exists() && vanillaJsonFile.length() == 0){
+                            throw new RuntimeException("Minecraft "+versionMessage+ " is needed by " +realVersion); }
+
+                        listener.onDownloadDone();
+                    } catch (Exception e) {
+                        String tryagain = !isOnline ? "Please ensure you have an internet connection" : "Please try again on your Microsoft Account";
+                        Tools.showErrorRemote(versionMessage + " is not currently installed. "+ tryagain, e);
                     }
+                }else {
                 downloadGame(activity, version, realVersion);
                 listener.onDownloadDone();
-            }catch (UnknownHostException e){
+                }
-                Log.i("DownloadMirror", e.toString());
-                Tools.showErrorRemote("Can't download Minecraft, no internet connection found", e);
             }catch (Exception e) {
                 listener.onDownloadFailed(e);
             }
@@ -473,7 +500,27 @@ public class MinecraftDownloader {
          * Since Minecraft libraries are stored in maven repositories, try to use
          * this when downloading libraries without hashes in the json.
          */
-        private void tryGetLibrarySha1() {
+        private void tryGetLibrarySha1() throws IOException {
+            File sha1CacheDir = new File(Tools.DIR_CACHE + "/sha1hashes");
+            File cacheFile = new File(sha1CacheDir.getAbsolutePath() + FileUtils.getFileName(mTargetUrl) + ".sha");
+
+            // Only use cache when its offline. No point in having cache invalidation now!
+            if (!isOnline || !LauncherPreferences.PREF_CHECK_LIBRARY_SHA) { // Well not only offlines..this setting speeds up launch times at least!
+                try (BufferedReader cacheFileReader = new BufferedReader(new FileReader(cacheFile))) {
+                    mTargetSha1 = cacheFileReader.readLine();
+                    if (mTargetSha1 != null) {
+                        Log.i("MinecraftDownloader", "Reading Hash from cache: " + mTargetSha1 + " from " + cacheFile);
+                    } else if (cacheFile.exists()) {
+                        Log.i("MinecraftDownloader", "Deleting invalid hash from cache: " + cacheFile);
+                        cacheFile.delete();
+                    }
+                } catch (FileNotFoundException ignored) {
+                    mTargetSha1 = null;
+                    Log.w("MinecraftDownloader", "Failed to read hash for " + cacheFile);
+                }
+                return;
+            }
+
             String resultHash = null;
             try {
                 resultHash = downloadSha1();
@@ -481,10 +528,21 @@ public class MinecraftDownloader {
                 mInternetUsageCounter.getAndAdd(40);
             } catch (IOException e) {
                 Log.i("MinecraftDownloader", "Failed to download hash", e);
+                if (cacheFile.exists() && new BufferedReader(new FileReader(cacheFile)).readLine() == null) {
+                    Log.i("MinecraftDownloader", "Deleting failed hash download from cache: " + cacheFile);
+                    cacheFile.delete();
+                }
             }
             if (resultHash != null) {
                 Log.i("MinecraftDownloader", "Got hash: " + resultHash + " for " + FileUtils.getFileName(mTargetUrl));
                 mTargetSha1 = resultHash;
+                if (!sha1CacheDir.exists()) {
+                    sha1CacheDir.mkdir(); // If mkdir() fails, something went wrong with initializing /data/data/. mkdirs() isn't used on purpose
+                }
+                try (FileWriter writeHash = new FileWriter(cacheFile)) {
+                    Log.i("MinecraftDownloader", "Saving hash: " + resultHash + " for " + FileUtils.getFileName(mTargetUrl) + " to " + cacheFile);
+                    writeHash.write(resultHash);
+                }
             }
         }
 

app_pojavlauncher/src/main/java/net/kdt/pojavlaunch/utils/DownloadUtils.java

@@ -61,6 +61,12 @@ public class DownloadUtils {
         FileUtils.ensureParentDirectory(out);
         try (FileOutputStream fileOutputStream = new FileOutputStream(out)) {
             download(url, fileOutputStream);
+        } catch (IOException e) {
+            if (out.length() < 1) { // Only delete it if file is 0 bytes cause this file might already be downloaded and something else went wrong.
+                Log.i("DownloadUtils", "Cleaning up failed download: " + out.getAbsolutePath());
+                out.delete();
+                throw e;
+            }
         }
     }