Check storage before download image

app/src/main/java/com/hippo/ehviewer/spider/SpiderDen.java

@@ -76,6 +76,11 @@ public final class SpiderDen {
         if (dir != null) {
             // Read from DB
             String dirname = EhDB.getDownloadDirname(galleryInfo.gid);
+            if (null != dirname) {
+                // Some dirname may be invalid in some version
+                dirname = FileUtils.sanitizeFilename(dirname);
+                EhDB.putDownloadDirname(galleryInfo.gid, dirname);
+            }
 
             // Find it
             if (null == dirname) {
@@ -128,6 +133,17 @@ public final class SpiderDen {
         return mDownloadDir != null && mDownloadDir.ensureDir();
     }
 
+    public boolean isReady() {
+        switch (mMode) {
+            case SpiderQueen.MODE_READ:
+                return sCache != null;
+            case SpiderQueen.MODE_DOWNLOAD:
+                return mDownloadDir != null && mDownloadDir.isDirectory();
+            default:
+                return false;
+        }
+    }
+
     @Nullable
     public UniFile getDownloadDir() {
         return mDownloadDir != null && mDownloadDir.isDirectory() ? mDownloadDir : null;

app/src/main/java/com/hippo/ehviewer/spider/SpiderQueen.java

@@ -1238,7 +1238,7 @@ public class SpiderQueen implements Runnable {
                 Log.i(TAG, Thread.currentThread().getName() + ": start");
             }
 
-            while (!Thread.currentThread().isInterrupted() && runInternal());
+            while (mSpiderDen.isReady() && !Thread.currentThread().isInterrupted() && runInternal());
 
             boolean finish;
             // Clear in spider worker array