12 files changed, 624 insertions, 1 deletions
diff --git a/src/com/isode/stroke/avatars/AvatarManager.java b/src/com/isode/stroke/avatars/AvatarManager.java
new file mode 100755
index 0000000..8bb8e71
--- /dev/null
+++ b/src/com/isode/stroke/avatars/AvatarManager.java
@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2010 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+/*
+ * Copyright (c) 2015 Tarun Gupta.
+ * Licensed under the simplified BSD license.
+ * See Documentation/Licenses/BSD-simplified.txt for more information.
+ */
+
+package com.isode.stroke.avatars;
+
+import java.nio.file.Path;
+import com.isode.stroke.jid.JID;
+import com.isode.stroke.base.ByteArray;
+import com.isode.stroke.signals.Signal1;
+
+public interface AvatarManager {
+
+	public ByteArray getAvatar(JID jid);
+	public Path getAvatarPath(JID jid);
+	public Signal1<JID> onAvatarChanged = new Signal1<JID>();
+}
+\ No newline at end of file
diff --git a/src/com/isode/stroke/avatars/AvatarManagerImpl.java b/src/com/isode/stroke/avatars/AvatarManagerImpl.java
new file mode 100755
index 0000000..b324b3e
--- /dev/null
+++ b/src/com/isode/stroke/avatars/AvatarManagerImpl.java
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2010-2013 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+/*
+ * Copyright (c) 2015 Tarun Gupta.
+ * Licensed under the simplified BSD license.
+ * See Documentation/Licenses/BSD-simplified.txt for more information.
+ */
+
+package com.isode.stroke.avatars;
+
+import com.isode.stroke.avatars.AvatarManager;
+import com.isode.stroke.avatars.CombinedAvatarProvider;
+import com.isode.stroke.muc.MUCRegistry;
+import com.isode.stroke.avatars.AvatarStorage;
+import com.isode.stroke.client.StanzaChannel;
+import com.isode.stroke.vcards.VCardManager;
+import com.isode.stroke.avatars.VCardUpdateAvatarManager;
+import com.isode.stroke.avatars.VCardAvatarManager;
+import com.isode.stroke.avatars.OfflineAvatarManager;
+import com.isode.stroke.crypto.CryptoProvider;
+import com.isode.stroke.base.ByteArray;
+import com.isode.stroke.jid.JID;
+import com.isode.stroke.signals.Slot1;
+import java.nio.file.*;
+import com.isode.stroke.signals.SignalConnection;
+
+public class AvatarManagerImpl implements AvatarManager {
+
+	private CombinedAvatarProvider combinedAvatarProvider = new CombinedAvatarProvider();
+	private AvatarStorage avatarStorage;
+	private VCardUpdateAvatarManager vcardUpdateAvatarManager;
+	private VCardAvatarManager vcardAvatarManager;
+	private OfflineAvatarManager offlineAvatarManager;
+	private SignalConnection onAvatarChangedConnection;
+
+	public AvatarManagerImpl(VCardManager vcardManager, StanzaChannel stanzaChannel, AvatarStorage avatarStorage, CryptoProvider crypto) {
+		this(vcardManager, stanzaChannel, avatarStorage, crypto, null);
+	}
+
+	public AvatarManagerImpl(VCardManager vcardManager, StanzaChannel stanzaChannel, AvatarStorage avatarStorage, CryptoProvider crypto, MUCRegistry mucRegistry) {
+		this.avatarStorage = avatarStorage;
+		vcardUpdateAvatarManager = new VCardUpdateAvatarManager(vcardManager, stanzaChannel, avatarStorage, crypto, mucRegistry);
+		combinedAvatarProvider.addProvider(vcardUpdateAvatarManager);
+
+		vcardAvatarManager = new VCardAvatarManager(vcardManager, avatarStorage, crypto, mucRegistry);
+		combinedAvatarProvider.addProvider(vcardAvatarManager);
+
+		offlineAvatarManager = new OfflineAvatarManager(avatarStorage);
+		combinedAvatarProvider.addProvider(offlineAvatarManager);
+
+		onAvatarChangedConnection = combinedAvatarProvider.onAvatarChanged.connect(new Slot1<JID>() {
+
+			public void call(JID p1) {
+				handleCombinedAvatarChanged(p1);
+			}
+		});
+	}
+
+	public Path getAvatarPath(JID jid) {
+		String hash = combinedAvatarProvider.getAvatarHash(jid);
+		if (hash != null && hash.length() != 0) {
+			return avatarStorage.getAvatarPath(hash);
+		}
+		return Paths.get("");
+	}
+
+	public ByteArray getAvatar(JID jid) {
+		String hash = combinedAvatarProvider.getAvatarHash(jid);
+		if (hash != null && hash.length() != 0) {
+			return avatarStorage.getAvatar(hash);
+		}
+		return new ByteArray();
+	}
+
+	private void handleCombinedAvatarChanged(JID jid) {
+		String hash = combinedAvatarProvider.getAvatarHash(jid);
+		assert(hash != null);
+		offlineAvatarManager.setAvatar(jid, hash);
+		onAvatarChanged.emit(jid);
+	}
+}
+\ No newline at end of file
diff --git a/src/com/isode/stroke/avatars/AvatarMemoryStorage.java b/src/com/isode/stroke/avatars/AvatarMemoryStorage.java
new file mode 100755
index 0000000..a3ad6f0
--- /dev/null
+++ b/src/com/isode/stroke/avatars/AvatarMemoryStorage.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2010 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+/*
+ * Copyright (c) 2015 Tarun Gupta.
+ * Licensed under the simplified BSD license.
+ * See Documentation/Licenses/BSD-simplified.txt for more information.
+ */
+
+package com.isode.stroke.avatars;
+
+import com.isode.stroke.avatars.AvatarStorage;
+import com.isode.stroke.base.ByteArray;
+import com.isode.stroke.jid.JID;
+import java.nio.file.*;
+import java.io.File;
+import java.util.*;
+
+public class AvatarMemoryStorage implements AvatarStorage {
+
+	private Map<String, ByteArray> avatars = new HashMap<String, ByteArray>();
+	private Map<JID, String> jidAvatars = new HashMap<JID, String>();
+
+	public boolean hasAvatar(String hash) {
+		return avatars.containsKey(hash);
+	}
+
+	public void addAvatar(String hash, ByteArray avatar) {
+		avatars.put(hash, avatar);
+	}
+
+	public ByteArray getAvatar(String hash) {
+		if(avatars.containsKey(hash)) {
+			return avatars.get(hash);
+		} else {
+			return new ByteArray();
+		}
+	}
+
+	public Path getAvatarPath(String hash) {
+		return (Paths.get("/avatars" + File.separator + hash)).toAbsolutePath();
+	}
+
+	public void setAvatarForJID(JID jid, String hash) {
+		jidAvatars.put(jid, hash);
+	}
+
+	public String getAvatarForJID(JID jid) {
+		if(jidAvatars.containsKey(jid)) {
+			return jidAvatars.get(jid);
+		} else {
+			return "";
+		}
+	}
+}
+\ No newline at end of file
diff --git a/src/com/isode/stroke/avatars/AvatarProvider.java b/src/com/isode/stroke/avatars/AvatarProvider.java
new file mode 100755
index 0000000..31fabb4
--- /dev/null
+++ b/src/com/isode/stroke/avatars/AvatarProvider.java
@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2010 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+/*
+ * Copyright (c) 2015 Tarun Gupta.
+ * Licensed under the simplified BSD license.
+ * See Documentation/Licenses/BSD-simplified.txt for more information.
+ */
+
+package com.isode.stroke.avatars;
+
+import com.isode.stroke.signals.Signal1;
+import com.isode.stroke.jid.JID;
+
+public interface AvatarProvider {
+
+	public String getAvatarHash(JID jid);
+	public Signal1<JID> onAvatarChanged = new Signal1<JID>();
+}
+\ No newline at end of file
diff --git a/src/com/isode/stroke/avatars/AvatarStorage.java b/src/com/isode/stroke/avatars/AvatarStorage.java
new file mode 100755
index 0000000..98f7e6f
--- /dev/null
+++ b/src/com/isode/stroke/avatars/AvatarStorage.java
@@ -0,0 +1,27 @@
+/*
+ * Copyright (c) 2010 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+/*
+ * Copyright (c) 2015 Tarun Gupta.
+ * Licensed under the simplified BSD license.
+ * See Documentation/Licenses/BSD-simplified.txt for more information.
+ */
+
+package com.isode.stroke.avatars;
+
+import com.isode.stroke.base.ByteArray;
+import com.isode.stroke.jid.JID;
+import java.nio.file.Path;
+
+public interface AvatarStorage {
+
+	public boolean hasAvatar(String hash);
+	public void addAvatar(String hash, ByteArray avatar);
+	public ByteArray getAvatar(String hash);
+	public Path getAvatarPath(String hash);
+
+	public void setAvatarForJID(JID jid, String hash);
+	public String getAvatarForJID(JID jid);
+}
+\ No newline at end of file
diff --git a/src/com/isode/stroke/avatars/CombinedAvatarProvider.java b/src/com/isode/stroke/avatars/CombinedAvatarProvider.java
new file mode 100755
index 0000000..0426bd6
--- /dev/null
+++ b/src/com/isode/stroke/avatars/CombinedAvatarProvider.java
@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2010 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+/*
+ * Copyright (c) 2015 Tarun Gupta.
+ * Licensed under the simplified BSD license.
+ * See Documentation/Licenses/BSD-simplified.txt for more information.
+ */
+
+package com.isode.stroke.avatars;
+
+import com.isode.stroke.avatars.AvatarProvider;
+import com.isode.stroke.signals.SignalConnection;
+import com.isode.stroke.signals.Slot1;
+import com.isode.stroke.jid.JID;
+import java.util.logging.Logger;
+import java.util.*;
+
+public class CombinedAvatarProvider implements AvatarProvider {
+
+	private Vector<AvatarProvider> providers = new Vector<AvatarProvider>();
+	private Map<JID, String> avatars = new HashMap<JID, String>();
+	private SignalConnection onAvatarChangedConnection_;
+	private Logger logger_ = Logger.getLogger(this.getClass().getName());
+
+	public String getAvatarHash(JID jid) {
+		return getCombinedAvatarAndCache(jid);
+	}
+
+	public void addProvider(AvatarProvider provider) {
+		onAvatarChangedConnection_ = provider.onAvatarChanged.connect(new Slot1<JID>() {
+
+			public void call(JID p1) {
+				handleAvatarChanged(p1);
+			}
+		});
+		providers.add(provider);
+	}
+
+	public void removeProvider(AvatarProvider provider) {
+		while(providers.contains(provider)) {
+			providers.remove(provider);
+			onAvatarChangedConnection_.disconnect();
+		}
+	}
+
+	private void handleAvatarChanged(JID jid) {
+		String oldHash = new String();
+		if(avatars.containsKey(jid)) {
+			oldHash = avatars.get(jid);
+		}
+		String newHash = getCombinedAvatarAndCache(jid);
+		if (newHash != null && !newHash.equals(oldHash)) {
+			logger_.fine("Avatar changed: " + jid + ": " + oldHash + " -> " + ((newHash != null) ? newHash : "NULL") + "\n");
+			onAvatarChanged.emit(jid);
+		}
+	}
+
+	private String getCombinedAvatarAndCache(JID jid) {
+		logger_.fine("JID: " + jid + "\n");
+		String hash = null;
+		for (int i = 0; i < providers.size() && (hash==null); ++i) {
+			hash = providers.get(i).getAvatarHash(jid);
+			logger_.fine("Provider " + providers.get(i) + ": " + ((hash != null) ? hash : "NULL") + "\n");
+		}
+		if (hash != null) {
+			avatars.put(jid, hash);
+		} else {
+			avatars.put(jid, "");
+		}
+		return hash;
+	}
+}
+\ No newline at end of file
diff --git a/src/com/isode/stroke/avatars/DummyAvatarManager.java b/src/com/isode/stroke/avatars/DummyAvatarManager.java
new file mode 100755
index 0000000..f1dfe41
--- /dev/null
+++ b/src/com/isode/stroke/avatars/DummyAvatarManager.java
@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2010 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+/*
+ * Copyright (c) 2015 Tarun Gupta.
+ * Licensed under the simplified BSD license.
+ * See Documentation/Licenses/BSD-simplified.txt for more information.
+ */
+
+package com.isode.stroke.avatars;
+
+import com.isode.stroke.avatars.AvatarManager;
+import com.isode.stroke.base.ByteArray;
+import com.isode.stroke.jid.JID;
+import java.nio.file.*;
+import java.io.File;
+import java.util.*;
+
+public class DummyAvatarManager implements AvatarManager {
+
+	private Map<JID, ByteArray> avatars = new HashMap<JID, ByteArray>();
+
+	public Path getAvatarPath(JID j) {
+		return (Paths.get("/avatars" + File.separator + j.toString())).toAbsolutePath();
+	}
+
+	public ByteArray getAvatar(JID jid) {
+		if(avatars.containsKey(jid)) {
+			return avatars.get(jid);
+		} else {
+			return new ByteArray();
+		}
+	}
+}
+\ No newline at end of file
diff --git a/src/com/isode/stroke/avatars/NullAvatarManager.java b/src/com/isode/stroke/avatars/NullAvatarManager.java
new file mode 100755
index 0000000..e69ed46
--- /dev/null
+++ b/src/com/isode/stroke/avatars/NullAvatarManager.java
@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2010 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+/*
+ * Copyright (c) 2015 Tarun Gupta.
+ * Licensed under the simplified BSD license.
+ * See Documentation/Licenses/BSD-simplified.txt for more information.
+ */
+
+package com.isode.stroke.avatars;
+
+import com.isode.stroke.avatars.AvatarManager;
+import com.isode.stroke.base.ByteArray;
+import com.isode.stroke.jid.JID;
+import java.nio.file.*;
+
+public class NullAvatarManager implements AvatarManager {
+
+	public Path getAvatarPath(JID j) {
+		return Paths.get("");
+	}
+
+	public ByteArray getAvatar(JID jid) {
+		return new ByteArray();
+	}
+}
+\ No newline at end of file
diff --git a/src/com/isode/stroke/avatars/OfflineAvatarManager.java b/src/com/isode/stroke/avatars/OfflineAvatarManager.java
new file mode 100755
index 0000000..fe5de08
--- /dev/null
+++ b/src/com/isode/stroke/avatars/OfflineAvatarManager.java
@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2010 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+/*
+ * Copyright (c) 2015 Tarun Gupta.
+ * Licensed under the simplified BSD license.
+ * See Documentation/Licenses/BSD-simplified.txt for more information.
+ */
+
+package com.isode.stroke.avatars;
+
+import com.isode.stroke.avatars.AvatarProvider;
+import com.isode.stroke.avatars.AvatarStorage;
+import com.isode.stroke.jid.JID;
+
+public class OfflineAvatarManager implements AvatarProvider {
+
+	private AvatarStorage avatarStorage;
+
+	public OfflineAvatarManager(AvatarStorage avatarStorage) {
+		this.avatarStorage = avatarStorage;
+	}
+
+	public String getAvatarHash(JID jid) {
+		return avatarStorage.getAvatarForJID(jid);
+	}
+
+	public void setAvatar(JID jid, String hash) {
+		if (!getAvatarHash(jid).equals(hash)) {
+			avatarStorage.setAvatarForJID(jid, hash);
+			onAvatarChanged.emit(jid);
+		}
+	}
+}
+\ No newline at end of file
diff --git a/src/com/isode/stroke/avatars/VCardAvatarManager.java b/src/com/isode/stroke/avatars/VCardAvatarManager.java
new file mode 100755
index 0000000..b2efcf2
--- /dev/null
+++ b/src/com/isode/stroke/avatars/VCardAvatarManager.java
@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2010-2013 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+/*
+ * Copyright (c) 2015 Tarun Gupta.
+ * Licensed under the simplified BSD license.
+ * See Documentation/Licenses/BSD-simplified.txt for more information.
+ */
+
+package com.isode.stroke.avatars;
+
+import com.isode.stroke.avatars.AvatarProvider;
+import com.isode.stroke.jid.JID;
+import com.isode.stroke.elements.VCard;
+import com.isode.stroke.crypto.CryptoProvider;
+import com.isode.stroke.stringcodecs.Hexify;
+import com.isode.stroke.avatars.AvatarStorage;
+import com.isode.stroke.muc.MUCRegistry;
+import com.isode.stroke.vcards.VCardManager;
+import com.isode.stroke.signals.Slot2;
+import java.util.logging.Logger;
+import com.isode.stroke.signals.SignalConnection;
+
+public class VCardAvatarManager implements AvatarProvider {
+
+	private VCardManager vcardManager_;
+	private AvatarStorage avatarStorage_;
+	private CryptoProvider crypto_;
+	private MUCRegistry mucRegistry_;
+	private SignalConnection onVCardChangedConnection_;
+	private Logger logger_ = Logger.getLogger(this.getClass().getName());
+
+	public VCardAvatarManager(VCardManager vcardManager, AvatarStorage avatarStorage, CryptoProvider crypto) {
+		this(vcardManager, avatarStorage, crypto, null);
+	}
+
+	public VCardAvatarManager(VCardManager vcardManager, AvatarStorage avatarStorage, CryptoProvider crypto, MUCRegistry mucRegistry) {
+		this.vcardManager_ = vcardManager;
+		this.avatarStorage_ = avatarStorage;
+		this.crypto_ = crypto;
+		this.mucRegistry_ = mucRegistry;
+		onVCardChangedConnection_ = vcardManager.onVCardChanged.connect(new Slot2<JID, VCard>() {
+
+			public void call(JID p1, VCard vcard) {
+				handleVCardChanged(p1);
+			}	
+		});
+	}
+
+	public String getAvatarHash(JID jid) {
+		JID avatarJID = getAvatarJID(jid);
+		String hash = vcardManager_.getPhotoHash(avatarJID);
+		if(hash.length() != 0) {
+			if (!avatarStorage_.hasAvatar(hash)) {
+				VCard vCard = vcardManager_.getVCard(avatarJID);
+				if (vCard != null) {
+					String newHash = Hexify.hexify(crypto_.getSHA1Hash(vCard.getPhoto()));
+					if (!newHash.equals(hash)) {
+						// Shouldn't happen, but sometimes seem to. Might be fixed if we
+						// move to a safer backend.
+						logger_.warning("Inconsistent vCard photo hash cache");
+						hash = newHash;
+					}
+					avatarStorage_.addAvatar(hash, vCard.getPhoto());
+				}
+				else {
+					// Can happen if the cache is inconsistent.
+					hash = "";
+				}
+			}
+		}
+		return hash;
+	}
+
+	private void handleVCardChanged(JID from) {
+		// We don't check whether the avatar actually changed. Direct use of this
+		// manager could cause unnecessary updates, but in practice, this will be
+		// caught by the wrapping CombinedAvatarManager anyway.
+		onAvatarChanged.emit(from);
+	}
+
+	private JID getAvatarJID(JID jid) {
+		JID bareFrom = jid.toBare();
+		return (mucRegistry_ != null && mucRegistry_.isMUC(bareFrom)) ? jid : bareFrom;
+	}
+}
diff --git a/src/com/isode/stroke/avatars/VCardUpdateAvatarManager.java b/src/com/isode/stroke/avatars/VCardUpdateAvatarManager.java
new file mode 100755
index 0000000..ce61892
--- /dev/null
+++ b/src/com/isode/stroke/avatars/VCardUpdateAvatarManager.java
@@ -0,0 +1,140 @@
+/*
+ * Copyright (c) 2010-2014 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+/*
+ * Copyright (c) 2015 Tarun Gupta.
+ * Licensed under the simplified BSD license.
+ * See Documentation/Licenses/BSD-simplified.txt for more information.
+ */
+
+package com.isode.stroke.avatars;
+
+import java.util.Map;
+import java.util.HashMap;
+import com.isode.stroke.avatars.AvatarProvider;
+import com.isode.stroke.jid.JID;
+import com.isode.stroke.elements.VCard;
+import com.isode.stroke.elements.Presence;
+import com.isode.stroke.elements.ErrorPayload;
+import com.isode.stroke.elements.VCardUpdate;
+import com.isode.stroke.client.StanzaChannel;
+import com.isode.stroke.vcards.GetVCardRequest;
+import com.isode.stroke.crypto.CryptoProvider;
+import com.isode.stroke.stringcodecs.Hexify;
+import com.isode.stroke.avatars.AvatarStorage;
+import com.isode.stroke.muc.MUCRegistry;
+import com.isode.stroke.vcards.VCardManager;
+import com.isode.stroke.signals.Slot2;
+import com.isode.stroke.signals.Slot1;
+import java.util.logging.Logger;
+import com.isode.stroke.signals.SignalConnection;
+
+public class VCardUpdateAvatarManager implements AvatarProvider {
+
+	private VCardManager vcardManager_;
+	private AvatarStorage avatarStorage_;
+	private CryptoProvider crypto_;
+	private MUCRegistry mucRegistry_;
+	private Map<JID, String> avatarHashes_ = new HashMap<JID, String>();
+	private SignalConnection onPresenceReceivedConnection;
+	private SignalConnection onAvailableChangedConnection;
+	private SignalConnection onVCardChangedConnection;
+	private Logger logger_ = Logger.getLogger(this.getClass().getName());
+
+	public VCardUpdateAvatarManager(VCardManager vcardManager, StanzaChannel stanzaChannel, AvatarStorage avatarStorage, CryptoProvider crypto) {
+		this(vcardManager, stanzaChannel, avatarStorage, crypto, null);
+	}
+
+	public VCardUpdateAvatarManager(VCardManager vcardManager, StanzaChannel stanzaChannel, AvatarStorage avatarStorage, CryptoProvider crypto, MUCRegistry mucRegistry) {
+		this.vcardManager_ = vcardManager;
+		this.avatarStorage_ = avatarStorage;
+		this.crypto_ = crypto;
+		this.mucRegistry_ = mucRegistry;
+		onPresenceReceivedConnection = stanzaChannel.onPresenceReceived.connect(new Slot1<Presence>() {
+
+			public void call(Presence p1) {
+				handlePresenceReceived(p1);
+			}
+		});
+		onAvailableChangedConnection = stanzaChannel.onAvailableChanged.connect(new Slot1<Boolean>() {
+
+			public void call(Boolean b) {
+				handleStanzaChannelAvailableChanged(b);
+			}
+		});
+		onVCardChangedConnection = vcardManager_.onVCardChanged.connect(new Slot2<JID, VCard>() {
+
+			public void call(JID p1, VCard vcard) {
+				handleVCardChanged(p1, vcard);
+			}
+		});
+	}
+
+	public String getAvatarHash(JID jid) {
+		if(avatarHashes_.containsKey(jid)) {
+			return avatarHashes_.get(jid);
+		} else {
+			return null;
+		}
+	}
+
+	private void handlePresenceReceived(Presence presence) {
+		VCardUpdate update = presence.getPayload(new VCardUpdate());
+		if (update == null || presence.getPayload(new ErrorPayload()) != null) {
+			return;
+		}
+		JID from = getAvatarJID(presence.getFrom());
+		if (update.getPhotoHash().equals(getAvatarHash(from))) {
+			return;
+		}
+		logger_.fine("Updated hash: " + from + "-> " + update.getPhotoHash() + "\n");
+		if (avatarStorage_.hasAvatar(update.getPhotoHash())) {
+			setAvatarHash(from, update.getPhotoHash());
+		}
+		else {
+			vcardManager_.requestVCard(from);
+		}
+	}
+
+	private void handleStanzaChannelAvailableChanged(boolean available) {
+		if (available) {
+			Map<JID, String> oldAvatarHashes = new HashMap<JID, String>();
+			oldAvatarHashes.putAll(avatarHashes_);
+			avatarHashes_.clear();
+			for (Map.Entry<JID, String> entry : oldAvatarHashes.entrySet()) {
+				onAvatarChanged.emit(entry.getKey());
+			}
+		}
+	}
+
+	private void handleVCardChanged(JID from, VCard vCard) {
+		if (vCard == null) {
+			logger_.fine("Missing element: " + from + ": null vcard payload\n");
+			return;
+		}
+
+		if (vCard.getPhoto().isEmpty()) {
+			setAvatarHash(from, "");
+		}
+		else {
+			String hash = Hexify.hexify(crypto_.getSHA1Hash(vCard.getPhoto()));
+			if (!avatarStorage_.hasAvatar(hash)) {
+				avatarStorage_.addAvatar(hash, vCard.getPhoto());
+			}
+			setAvatarHash(from, hash);
+		}
+	}
+
+	private void setAvatarHash(JID from, String hash) {
+		logger_.fine("Updating hash: " + from + " -> " + hash + "\n");
+		avatarHashes_.put(from, hash);
+		onAvatarChanged.emit(from);
+	}
+
+	private JID getAvatarJID(JID jid) {
+		JID bareFrom = jid.toBare();
+		return (mucRegistry_ != null && mucRegistry_.isMUC(bareFrom)) ? jid : bareFrom;
+	}
+}
diff --git a/src/com/isode/stroke/elements/VCard.java b/src/com/isode/stroke/elements/VCard.java
index f9b294b..91a9093 100644
--- a/src/com/isode/stroke/elements/VCard.java
+++ b/src/com/isode/stroke/elements/VCard.java
@@ -132,7 +132,14 @@ public class VCard extends Payload implements Serializable {
     public final String getNickname() { return nick_; }
 
     public void setPhoto(final ByteArray photo) { photo_ = photo; }
-    public final ByteArray getPhoto() { return photo_; }
+    public final ByteArray getPhoto() {
+    	if(this.photo_ != null) {
+    		return photo_;
+    	}
+    	else {
+    		return new ByteArray();
+    	}
+    }
 
     public void setPhotoType(final String photoType) { photoType_ = photoType; }
     public final String getPhotoType() { return photoType_; }