Fix disk LRU cache key formatting error

We check and modify all the alphabetic ascii to lowercase, and then we
replace not permitted char with "_"

We also add a checksum to the key to avoid collisions in some cases.

Fix the issue related to:
Failed to get Bitmap from DiskLruCache:keys must match regex [a-z0-9_-]{1,64}:
"https://igalia.github.io/wolvic-3D-environments/spring/spring.png"
-> "585e57a6_https___igalia_github_io_wolvic-3d-environments_spring_"

Now we can access the external environments bitmap offline after
they have been loaded once.

Signed-off-by: Songlin Jiang <[email protected]>

app/src/common/shared/com/igalia/wolvic/utils/BitmapCache.java

@@ -18,6 +18,7 @@
 import java.io.IOException;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.Executor;
+import java.util.zip.CRC32;
 
 public class BitmapCache {
     private Context mContext;
@@ -32,6 +33,16 @@ public class BitmapCache {
     private Surface mCaptureSurface;
     private boolean mCapturedAcquired;
 
+    private String normalizeKey(@NonNull String input) {
+        // DiskLruCache keys must match the regex [a-z0-9_-]{1,64}
+        final int MAX_LENGTH = 64;
+        CRC32 crc = new CRC32();
+        crc.update(input.getBytes());
+
+        String key = Long.toHexString(crc.getValue()) + '_' + input.toLowerCase().replaceAll("[^a-z0-9_-]", "_");
+        return key.substring(0, Math.min(key.length(), MAX_LENGTH));
+    }
+
     public static BitmapCache getInstance(Context aContext) {
         return ((VRBrowserApplication)aContext.getApplicationContext()).getBitmapCache();
     }
@@ -75,11 +86,13 @@ void initDiskCache() {
     }
 
     public void addBitmap(@NonNull String aKey, @NonNull Bitmap aBitmap) {
+        aKey = normalizeKey(aKey);
         mMemoryCache.put(aKey, aBitmap);
+        String finalAKey = aKey;
         runIO(() -> {
             DiskLruCache.Editor editor = null;
             try {
-                editor = mDiskCache.edit(aKey);
+                editor = mDiskCache.edit(finalAKey);
                 if (editor != null) {
                     aBitmap.compress(Bitmap.CompressFormat.PNG, 80, editor.newOutputStream(0));
                     editor.commit();
@@ -100,21 +113,23 @@ public void addBitmap(@NonNull String aKey, @NonNull Bitmap aBitmap) {
     }
 
     public @NonNull CompletableFuture<Bitmap> getBitmap(@NonNull String aKey) {
+        aKey = normalizeKey(aKey);
         Bitmap cached = mMemoryCache.get(aKey);
         if (cached != null) {
             return CompletableFuture.completedFuture(cached);
         } else {
             CompletableFuture<Bitmap> result = new CompletableFuture<>();
+            String finalAKey = aKey;
             runIO(() -> {
-                try (DiskLruCache.Snapshot snapshot = mDiskCache.get(aKey)){
+                try (DiskLruCache.Snapshot snapshot = mDiskCache.get(finalAKey)){
                     if (snapshot != null) {
                         Bitmap bitmap = BitmapFactory.decodeStream(snapshot.getInputStream(0));
                         if (bitmap != null) {
                             mMainThreadExecutor.execute(() -> {
-                                if (mMemoryCache.get(aKey) == null) {
+                                if (mMemoryCache.get(finalAKey) == null) {
                                     // Do not update cache if it already contains a value
                                     // A tab could have saved a new image while we were loading the cached disk image.
-                                    mMemoryCache.put(aKey, bitmap);
+                                    mMemoryCache.put(finalAKey, bitmap);
                                 }
                                 result.complete(bitmap);
                             });
@@ -135,17 +150,20 @@ public void addBitmap(@NonNull String aKey, @NonNull Bitmap aBitmap) {
     }
 
     public void removeBitmap(@NonNull String aKey) {
+        aKey = normalizeKey(aKey);
         mMemoryCache.remove(aKey);
+        String finalAKey = aKey;
         runIO(() -> {
             try {
-                mDiskCache.remove(aKey);
+                mDiskCache.remove(finalAKey);
             } catch (Exception ex) {
                 Log.e(LOGTAG, "Failed to remove Bitmap from DiskLruCache:" + ex.getMessage());
             }
         });
     }
 
     public boolean hasBitmap(@NonNull String aKey) {
+        aKey = normalizeKey(aKey);
         return mMemoryCache.get(aKey) != null;
     }