Merge branch 'trz/rebase' into trz/rename

Conflicts:
	build.gradle
	src/main/java/de/thedevstack/conversationsplus/crypto/OtrEngine.java
	src/main/java/de/thedevstack/conversationsplus/entities/Account.java
	src/main/java/de/thedevstack/conversationsplus/entities/Contact.java
	src/main/java/de/thedevstack/conversationsplus/entities/Downloadable.java
	src/main/java/de/thedevstack/conversationsplus/entities/DownloadableFile.java
	src/main/java/de/thedevstack/conversationsplus/entities/DownloadablePlaceholder.java
	src/main/java/de/thedevstack/conversationsplus/entities/Message.java
	src/main/java/de/thedevstack/conversationsplus/generator/IqGenerator.java
	src/main/java/de/thedevstack/conversationsplus/http/HttpConnection.java
	src/main/java/de/thedevstack/conversationsplus/http/HttpConnectionManager.java
	src/main/java/de/thedevstack/conversationsplus/parser/AbstractParser.java
	src/main/java/de/thedevstack/conversationsplus/parser/MessageParser.java
	src/main/java/de/thedevstack/conversationsplus/parser/PresenceParser.java
	src/main/java/de/thedevstack/conversationsplus/persistance/DatabaseBackend.java
	src/main/java/de/thedevstack/conversationsplus/persistance/FileBackend.java
	src/main/java/de/thedevstack/conversationsplus/services/NotificationService.java
	src/main/java/de/thedevstack/conversationsplus/services/XmppConnectionService.java
	src/main/java/de/thedevstack/conversationsplus/ui/ConversationActivity.java
	src/main/java/de/thedevstack/conversationsplus/ui/ConversationFragment.java
	src/main/java/de/thedevstack/conversationsplus/ui/SettingsActivity.java
	src/main/java/de/thedevstack/conversationsplus/ui/StartConversationActivity.java
	src/main/java/de/thedevstack/conversationsplus/ui/adapter/AccountAdapter.java
	src/main/java/de/thedevstack/conversationsplus/ui/adapter/ConversationAdapter.java
	src/main/java/de/thedevstack/conversationsplus/ui/adapter/ListItemAdapter.java
	src/main/java/de/thedevstack/conversationsplus/ui/adapter/MessageAdapter.java
	src/main/java/de/thedevstack/conversationsplus/utils/UIHelper.java
	src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleConnection.java
	src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleConnectionManager.java
	src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleInbandTransport.java
	src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleSocks5Transport.java
	src/main/java/de/thedevstack/conversationsplus/xmpp/stanzas/MessagePacket.java
	src/main/java/eu/siacs/conversations/crypto/OtrEngine.java
	src/main/java/eu/siacs/conversations/crypto/OtrService.java
	src/main/java/eu/siacs/conversations/entities/DownloadablePlaceholder.java
	src/main/java/eu/siacs/conversations/entities/TransferablePlaceholder.java
	src/main/java/eu/siacs/conversations/http/HttpConnection.java
	src/main/java/eu/siacs/conversations/http/HttpDownloadConnection.java
	src/main/res/layout/activity_about.xml

11 files changed, 328 insertions, 218 deletions

diff --git a/src/main/java/de/thedevstack/conversationsplus/entities/Account.java b/src/main/java/de/thedevstack/conversationsplus/entities/Account.java
index 1b6539da..530adf06 100644
--- a/src/main/java/de/thedevstack/conversationsplus/entities/Account.java
+++ b/src/main/java/de/thedevstack/conversationsplus/entities/Account.java
@@ -44,6 +44,10 @@ public class Account extends AbstractEntity {
 	public static final int OPTION_REGISTER = 2;
 	public static final int OPTION_USECOMPRESSION = 3;
 
+	public boolean httpUploadAvailable() {
+		return xmppConnection != null && xmppConnection.getFeatures().httpUpload();
+	}
+
 	public static enum State {
 		DISABLED,
 		OFFLINE,
@@ -117,7 +121,7 @@ public class Account extends AbstractEntity {
 	protected JSONObject keys = new JSONObject();
 	protected String avatar;
 	protected boolean online = false;
-	private OtrEngine otrEngine = null;
+	private OtrService mOtrService = null;
 	private XmppConnection xmppConnection = null;
 	private long mEndGracePeriod = 0L;
 	private String otrFingerprint;
@@ -229,11 +233,17 @@ public class Account extends AbstractEntity {
 		return jid.getResourcepart();
 	}
 
-	public void setResource(final String resource) {
-		try {
-			jid = Jid.fromParts(jid.getLocalpart(), jid.getDomainpart(), resource);
-		} catch (final InvalidJidException ignored) {
+	public boolean setResource(final String resource) {
+		final String oldResource = jid.getResourcepart();
+		if (oldResource == null || !oldResource.equals(resource)) {
+			try {
+				jid = Jid.fromParts(jid.getLocalpart(), jid.getDomainpart(), resource);
+				return true;
+			} catch (final InvalidJidException ignored) {
+				return true;
+			}
 		}
+		return false;
 	}
 
 	public Jid getJid() {
@@ -267,12 +277,12 @@ public class Account extends AbstractEntity {
 		return values;
 	}
 
-	public void initOtrEngine(final XmppConnectionService context) {
-		this.otrEngine = new OtrEngine(context, this);
+	public void initAccountServices(final XmppConnectionService context) {
+		this.mOtrService = new OtrService(context, this);
 	}
 
-	public OtrEngine getOtrEngine() {
-		return this.otrEngine;
+	public OtrService getOtrService() {
+		return this.mOtrService;
 	}
 
 	public XmppConnection getXmppConnection() {
@@ -286,10 +296,10 @@ public class Account extends AbstractEntity {
 	public String getOtrFingerprint() {
 		if (this.otrFingerprint == null) {
 			try {
-				if (this.otrEngine == null) {
+				if (this.mOtrService == null) {
 					return null;
 				}
-				final PublicKey publicKey = this.otrEngine.getPublicKey();
+				final PublicKey publicKey = this.mOtrService.getPublicKey();
 				if (publicKey == null || !(publicKey instanceof DSAPublicKey)) {
 					return null;
 				}
diff --git a/src/main/java/de/thedevstack/conversationsplus/entities/Bookmark.java b/src/main/java/de/thedevstack/conversationsplus/entities/Bookmark.java
index 8a6b1405..9e67bf2d 100644
--- a/src/main/java/de/thedevstack/conversationsplus/entities/Bookmark.java
+++ b/src/main/java/de/thedevstack/conversationsplus/entities/Bookmark.java
@@ -2,6 +2,8 @@ package de.thedevstack.conversationsplus.entities;
 
 import android.graphics.Color;
 
+import android.graphics.Color;
+
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Locale;
@@ -82,12 +84,7 @@ public class Bookmark extends Element implements ListItem {
 	}
 
 	public String getNick() {
-		Element nick = this.findChild("nick");
-		if (nick != null) {
-			return nick.getContent();
-		} else {
-			return null;
-		}
+		return this.findChildContent("nick");
 	}
 
 	public void setNick(String nick) {
@@ -103,12 +100,7 @@ public class Bookmark extends Element implements ListItem {
 	}
 
 	public String getPassword() {
-		Element password = this.findChild("password");
-		if (password != null) {
-			return password.getContent();
-		} else {
-			return null;
-		}
+		return this.findChildContent("password");
 	}
 
 	public void setPassword(String password) {
diff --git a/src/main/java/de/thedevstack/conversationsplus/entities/Contact.java b/src/main/java/de/thedevstack/conversationsplus/entities/Contact.java
index c4f1c9eb..d72a1197 100644
--- a/src/main/java/de/thedevstack/conversationsplus/entities/Contact.java
+++ b/src/main/java/de/thedevstack/conversationsplus/entities/Contact.java
@@ -16,6 +16,7 @@ import de.thedevstack.conversationsplus.utils.UIHelper;
 import de.thedevstack.conversationsplus.xml.Element;
 import de.thedevstack.conversationsplus.xmpp.jid.InvalidJidException;
 import de.thedevstack.conversationsplus.xmpp.jid.Jid;
+import de.thedevstack.conversationsplus.xmpp.pep.Avatar;
 
 public class Contact implements ListItem, Blockable {
 	public static final String TABLENAME = "contacts";
@@ -41,11 +42,11 @@ public class Contact implements ListItem, Blockable {
 	protected int subscription = 0;
 	protected String systemAccount;
 	protected String photoUri;
-	protected String avatar;
 	protected JSONObject keys = new JSONObject();
 	protected JSONArray groups = new JSONArray();
 	protected Presences presences = new Presences();
 	protected Account account;
+	protected Avatar avatar;
 
 	public Contact(final String account, final String systemName, final String serverName,
 			final Jid jid, final int subscription, final String photoUri,
@@ -62,7 +63,11 @@ public class Contact implements ListItem, Blockable {
 		} catch (JSONException e) {
 			this.keys = new JSONObject();
 		}
-		this.avatar = avatar;
+		if (avatar != null) {
+			this.avatar = new Avatar();
+			this.avatar.sha1sum = avatar;
+			this.avatar.origin = Avatar.Origin.VCARD; //always assume worst
+		}
 		try {
 			this.groups = (groups == null ? new JSONArray() : new JSONArray(groups));
 		} catch (JSONException e) {
@@ -136,10 +141,10 @@ public class Contact implements ListItem, Blockable {
 				tags.add(new Tag("away", 0xffff9800));
 				break;
 			case Presences.XA:
-				tags.add(new Tag("not available", 0xffe51c23));
+				tags.add(new Tag("not available", 0xfff44336));
 				break;
 			case Presences.DND:
-				tags.add(new Tag("dnd", 0xffe51c23));
+				tags.add(new Tag("dnd", 0xfff44336));
 				break;
 		}
 		if (isBlocked()) {
@@ -193,7 +198,7 @@ public class Contact implements ListItem, Blockable {
 		values.put(SYSTEMACCOUNT, systemAccount);
 		values.put(PHOTOURI, photoUri);
 		values.put(KEYS, keys.toString());
-		values.put(AVATAR, avatar);
+		values.put(AVATAR, avatar == null ? null : avatar.getFilename());
 		values.put(LAST_PRESENCE, lastseen.presence);
 		values.put(LAST_TIME, lastseen.time);
 		values.put(GROUPS, groups.toString());
@@ -238,8 +243,16 @@ public class Contact implements ListItem, Blockable {
 		return this.presences.getMostAvailableStatus();
 	}
 
-	public void setPhotoUri(String uri) {
-		this.photoUri = uri;
+	public boolean setPhotoUri(String uri) {
+		if (uri != null && !uri.equals(this.photoUri)) {
+			this.photoUri = uri;
+			return true;
+		} else if (this.photoUri != null && uri == null) {
+			this.photoUri = null;
+			return true;
+		} else {
+			return false;
+		}
 	}
 
 	public void setServerName(String serverName) {
@@ -417,17 +430,20 @@ public class Contact implements ListItem, Blockable {
 		return getJid().toDomainJid();
 	}
 
-	public boolean setAvatar(String filename) {
-		if (this.avatar != null && this.avatar.equals(filename)) {
+	public boolean setAvatar(Avatar avatar) {
+		if (this.avatar != null && this.avatar.equals(avatar)) {
 			return false;
 		} else {
-			this.avatar = filename;
+			if (this.avatar != null && this.avatar.origin == Avatar.Origin.PEP && avatar.origin == Avatar.Origin.VCARD) {
+				return false;
+			}
+			this.avatar = avatar;
 			return true;
 		}
 	}
 
 	public String getAvatar() {
-		return this.avatar;
+		return avatar == null ? null : avatar.getFilename();
 	}
 
 	public boolean deleteOtrFingerprint(String fingerprint) {
@@ -484,6 +500,10 @@ public class Contact implements ListItem, Blockable {
 		}
 	}
 
+	public boolean isSelf() {
+		return account.getJid().toBareJid().equals(getJid().toBareJid());
+	}
+
 	public static class Lastseen {
 		public long time;
 		public String presence;
diff --git a/src/main/java/de/thedevstack/conversationsplus/entities/Conversation.java b/src/main/java/de/thedevstack/conversationsplus/entities/Conversation.java
index 37cbff46..81c2eb4b 100644
--- a/src/main/java/de/thedevstack/conversationsplus/entities/Conversation.java
+++ b/src/main/java/de/thedevstack/conversationsplus/entities/Conversation.java
@@ -16,6 +16,7 @@ import java.security.interfaces.DSAPublicKey;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Comparator;
+import java.util.Iterator;
 import java.util.List;
 
 import de.thedevstack.conversationsplus.Config;
@@ -218,6 +219,11 @@ public class Conversation extends AbstractEntity implements Blockable {
 			messages.clear();
 			messages.addAll(this.messages);
 		}
+		for(Iterator<Message> iterator = messages.iterator(); iterator.hasNext();) {
+			if (iterator.next().wasMergedIntoPrevious()) {
+				iterator.remove();
+			}
+		}
 	}
 
 	@Override
@@ -243,6 +249,12 @@ public class Conversation extends AbstractEntity implements Blockable {
 		this.mLastReceivedOtrMessageId = id;
 	}
 
+	public int countMessages() {
+		synchronized (this.messages) {
+			return this.messages.size();
+		}
+	}
+
 
 	public interface OnMessageFound {
 		public void onMessageFound(final Message message);
@@ -413,7 +425,7 @@ public class Conversation extends AbstractEntity implements Blockable {
 			final SessionID sessionId = new SessionID(this.getJid().toBareJid().toString(),
 					presence,
 					"xmpp");
-			this.otrSession = new SessionImpl(sessionId, getAccount().getOtrEngine());
+			this.otrSession = new SessionImpl(sessionId, getAccount().getOtrService());
 			try {
 				if (sendStart) {
 					this.otrSession.startSession();
@@ -485,7 +497,7 @@ public class Conversation extends AbstractEntity implements Blockable {
 					return null;
 				}
 				DSAPublicKey remotePubKey = (DSAPublicKey) getOtrSession().getRemotePublicKey();
-				this.otrFingerprint = getAccount().getOtrEngine().getFingerprint(remotePubKey);
+				this.otrFingerprint = getAccount().getOtrService().getFingerprint(remotePubKey);
 			} catch (final OtrCryptoException | UnsupportedOperationException ignored) {
 				return null;
 			}
diff --git a/src/main/java/de/thedevstack/conversationsplus/entities/Downloadable.java b/src/main/java/de/thedevstack/conversationsplus/entities/Downloadable.java
deleted file mode 100644
index 20169dc8..00000000
--- a/src/main/java/de/thedevstack/conversationsplus/entities/Downloadable.java
+++ /dev/null
@@ -1,28 +0,0 @@
-package de.thedevstack.conversationsplus.entities;
-
-public interface Downloadable {
-
-	public final String[] VALID_IMAGE_EXTENSIONS = {"webp", "jpeg", "jpg", "png", "jpe"};
-	public final String[] VALID_CRYPTO_EXTENSIONS = {"pgp", "gpg", "otr"};
-
-	public static final int STATUS_UNKNOWN = 0x200;
-	public static final int STATUS_CHECKING = 0x201;
-	public static final int STATUS_FAILED = 0x202;
-	public static final int STATUS_OFFER = 0x203;
-	public static final int STATUS_DOWNLOADING = 0x204;
-	public static final int STATUS_DELETED = 0x205;
-	public static final int STATUS_OFFER_CHECK_FILESIZE = 0x206;
-	public static final int STATUS_UPLOADING = 0x207;
-
-	public boolean start();
-
-	public int getStatus();
-
-	public long getFileSize();
-
-	public int getProgress();
-
-	public String getMimeType();
-
-	public void cancel();
-}
diff --git a/src/main/java/de/thedevstack/conversationsplus/entities/DownloadableFile.java b/src/main/java/de/thedevstack/conversationsplus/entities/DownloadableFile.java
index 7566c199..9a677cd0 100644
--- a/src/main/java/de/thedevstack/conversationsplus/entities/DownloadableFile.java
+++ b/src/main/java/de/thedevstack/conversationsplus/entities/DownloadableFile.java
@@ -20,6 +20,8 @@ import javax.crypto.spec.IvParameterSpec;
 import javax.crypto.spec.SecretKeySpec;
 
 import de.thedevstack.conversationsplus.Config;
+import de.thedevstack.conversationsplus.utils.MimeUtils;
+
 import android.util.Log;
 
 public class DownloadableFile extends File {
@@ -56,16 +58,11 @@ public class DownloadableFile extends File {
 
 	public String getMimeType() {
 		String path = this.getAbsolutePath();
-		try {
-			String mime = URLConnection.guessContentTypeFromName(path.replace("#",""));
-			if (mime != null) {
-				return mime;
-			} else if (mime == null && path.endsWith(".webp")) {
-				return "image/webp";
-			} else {
-				return "";
-			}
-		} catch (final StringIndexOutOfBoundsException e) {
+		int start = path.lastIndexOf('.') + 1;
+		if (start < path.length()) {
+			String mime = MimeUtils.guessMimeTypeFromExtension(path.substring(start));
+			return mime == null ? "" : mime;
+		} else {
 			return "";
 		}
 	}
diff --git a/src/main/java/de/thedevstack/conversationsplus/entities/Message.java b/src/main/java/de/thedevstack/conversationsplus/entities/Message.java
index cd7556b3..68b47578 100644
--- a/src/main/java/de/thedevstack/conversationsplus/entities/Message.java
+++ b/src/main/java/de/thedevstack/conversationsplus/entities/Message.java
@@ -9,6 +9,8 @@ import java.util.Arrays;
 
 import de.thedevstack.conversationsplus.Config;
 import de.thedevstack.conversationsplus.utils.GeoHelper;
+import de.thedevstack.conversationsplus.utils.MimeUtils;
+import de.thedevstack.conversationsplus.utils.UIHelper;
 import de.thedevstack.conversationsplus.xmpp.jid.InvalidJidException;
 import de.thedevstack.conversationsplus.xmpp.jid.Jid;
 
@@ -16,6 +18,8 @@ public class Message extends AbstractEntity {
 
 	public static final String TABLENAME = "messages";
 
+	public static final String MERGE_SEPARATOR = " \u200B\n\n";
+
 	public static final int STATUS_RECEIVED = 0;
 	public static final int STATUS_UNSEND = 1;
 	public static final int STATUS_SEND = 2;
@@ -66,7 +70,7 @@ public class Message extends AbstractEntity {
 	protected String remoteMsgId = null;
 	protected String serverMsgId = null;
 	protected Conversation conversation = null;
-	protected Downloadable downloadable = null;
+	protected Transferable transferable = null;
 	private Message mNextMessage = null;
 	private Message mPreviousMessage = null;
 
@@ -95,9 +99,9 @@ public class Message extends AbstractEntity {
 	}
 
 	private Message(final String uuid, final String conversationUUid, final Jid counterpart,
-			final Jid trueCounterpart, final String body, final long timeSent,
-			final int encryption, final int status, final int type, final String remoteMsgId,
-			final String relativeFilePath, final String serverMsgId) {
+					final Jid trueCounterpart, final String body, final long timeSent,
+					final int encryption, final int status, final int type, final String remoteMsgId,
+					final String relativeFilePath, final String serverMsgId) {
 		this.uuid = uuid;
 		this.conversationUuid = conversationUUid;
 		this.counterpart = counterpart;
@@ -179,7 +183,7 @@ public class Message extends AbstractEntity {
 		values.put(TYPE, type);
 		values.put(REMOTE_MSG_ID, remoteMsgId);
 		values.put(RELATIVE_FILE_PATH, relativeFilePath);
-		values.put(SERVER_MSG_ID,serverMsgId);
+		values.put(SERVER_MSG_ID, serverMsgId);
 		return values;
 	}
 
@@ -211,7 +215,7 @@ public class Message extends AbstractEntity {
 				return null;
 			} else {
 				return this.conversation.getAccount().getRoster()
-					.getContactFromRoster(this.trueCounterpart);
+						.getContactFromRoster(this.trueCounterpart);
 			}
 		}
 	}
@@ -304,12 +308,12 @@ public class Message extends AbstractEntity {
 		this.trueCounterpart = trueCounterpart;
 	}
 
-	public Downloadable getDownloadable() {
-		return this.downloadable;
+	public Transferable getTransferable() {
+		return this.transferable;
 	}
 
-	public void setDownloadable(Downloadable downloadable) {
-		this.downloadable = downloadable;
+	public void setTransferable(Transferable transferable) {
+		this.transferable = transferable;
 	}
 
 	public boolean equals(Message message) {
@@ -317,15 +321,25 @@ public class Message extends AbstractEntity {
 			return this.serverMsgId.equals(message.getServerMsgId());
 		} else if (this.body == null || this.counterpart == null) {
 			return false;
-		} else if (message.getRemoteMsgId() != null) {
-			return (message.getRemoteMsgId().equals(this.remoteMsgId) || message.getRemoteMsgId().equals(this.uuid))
-					&& this.counterpart.equals(message.getCounterpart())
-					&& this.body.equals(message.getBody());
 		} else {
-			return this.remoteMsgId == null
-					&& this.counterpart.equals(message.getCounterpart())
-					&& this.body.equals(message.getBody())
-					&& Math.abs(this.getTimeSent() - message.getTimeSent()) < Config.PING_TIMEOUT * 500;
+			String body, otherBody;
+			if (this.hasFileOnRemoteHost()) {
+				body = getFileParams().url.toString();
+				otherBody = message.body == null ? null : message.body.trim();
+			} else {
+				body = this.body;
+				otherBody = message.body;
+			}
+			if (message.getRemoteMsgId() != null) {
+				return (message.getRemoteMsgId().equals(this.remoteMsgId) || message.getRemoteMsgId().equals(this.uuid))
+						&& this.counterpart.equals(message.getCounterpart())
+						&& body.equals(otherBody);
+			} else {
+				return this.remoteMsgId == null
+						&& this.counterpart.equals(message.getCounterpart())
+						&& body.equals(otherBody)
+						&& Math.abs(this.getTimeSent() - message.getTimeSent()) < Config.MESSAGE_MERGE_WINDOW * 1000;
+			}
 		}
 	}
 
@@ -359,41 +373,43 @@ public class Message extends AbstractEntity {
 
 	public boolean mergeable(final Message message) {
 		return message != null &&
-			(message.getType() == Message.TYPE_TEXT &&
-			 this.getDownloadable() == null &&
-			 message.getDownloadable() == null &&
-			 message.getEncryption() != Message.ENCRYPTION_PGP &&
-			 this.getType() == message.getType() &&
-			 //this.getStatus() == message.getStatus() &&
-			 isStatusMergeable(this.getStatus(),message.getStatus()) &&
-			 this.getEncryption() == message.getEncryption() &&
-			 this.getCounterpart() != null &&
-			 this.getCounterpart().equals(message.getCounterpart()) &&
-			 (message.getTimeSent() - this.getTimeSent()) <= (Config.MESSAGE_MERGE_WINDOW * 1000) &&
-			 !GeoHelper.isGeoUri(message.getBody()) &&
-			 !GeoHelper.isGeoUri(this.body) &&
-			 !message.bodyContainsDownloadable() &&
-			 !this.bodyContainsDownloadable() &&
-			 !message.getBody().startsWith(ME_COMMAND) &&
-			 !this.getBody().startsWith(ME_COMMAND)
-			);
+				(message.getType() == Message.TYPE_TEXT &&
+						this.getTransferable() == null &&
+						message.getTransferable() == null &&
+						message.getEncryption() != Message.ENCRYPTION_PGP &&
+						this.getType() == message.getType() &&
+						//this.getStatus() == message.getStatus() &&
+						isStatusMergeable(this.getStatus(), message.getStatus()) &&
+						this.getEncryption() == message.getEncryption() &&
+						this.getCounterpart() != null &&
+						this.getCounterpart().equals(message.getCounterpart()) &&
+						(message.getTimeSent() - this.getTimeSent()) <= (Config.MESSAGE_MERGE_WINDOW * 1000) &&
+						!GeoHelper.isGeoUri(message.getBody()) &&
+						!GeoHelper.isGeoUri(this.body) &&
+						message.treatAsDownloadable() == Decision.NEVER &&
+						this.treatAsDownloadable() == Decision.NEVER &&
+						!message.getBody().startsWith(ME_COMMAND) &&
+						!this.getBody().startsWith(ME_COMMAND) &&
+						!this.bodyIsHeart() &&
+						!message.bodyIsHeart()
+				);
 	}
 
 	private static boolean isStatusMergeable(int a, int b) {
 		return a == b || (
-				( a == Message.STATUS_SEND_RECEIVED && b == Message.STATUS_UNSEND)
-				|| (a == Message.STATUS_SEND_RECEIVED && b == Message.STATUS_SEND)
-				|| (a == Message.STATUS_UNSEND && b == Message.STATUS_SEND)
-				|| (a == Message.STATUS_UNSEND && b == Message.STATUS_SEND_RECEIVED)
-				|| (a == Message.STATUS_SEND && b == Message.STATUS_UNSEND)
-				|| (a == Message.STATUS_SEND && b == Message.STATUS_SEND_RECEIVED)
+				(a == Message.STATUS_SEND_RECEIVED && b == Message.STATUS_UNSEND)
+						|| (a == Message.STATUS_SEND_RECEIVED && b == Message.STATUS_SEND)
+						|| (a == Message.STATUS_UNSEND && b == Message.STATUS_SEND)
+						|| (a == Message.STATUS_UNSEND && b == Message.STATUS_SEND_RECEIVED)
+						|| (a == Message.STATUS_SEND && b == Message.STATUS_UNSEND)
+						|| (a == Message.STATUS_SEND && b == Message.STATUS_SEND_RECEIVED)
 		);
 	}
 
 	public String getMergedBody() {
 		final Message next = this.next();
 		if (this.mergeable(next)) {
-			return getBody() + '\n' + next.getMergedBody();
+			return getBody() + MERGE_SEPARATOR + next.getMergedBody();
 		}
 		return getBody();
 	}
@@ -429,119 +445,175 @@ public class Message extends AbstractEntity {
 		return (status > STATUS_RECEIVED || (contact != null && contact.trusted()));
 	}
 
-	public boolean bodyContainsDownloadable() {
-        /**
-         * there are a few cases where spaces result in an unwanted behavior, e.g.
-         * "http://upload.mitsu-freunde-bw.de/uploads/2015/03/i43b4bpr8.png /abc.png"
-         * or more than one image link in one message.
-         */
-        if (body.contains(" ")) {
-            return false;
-        }
-		try {
-			URL url = new URL(body);
-			if (!url.getProtocol().equalsIgnoreCase("http")
-					&& !url.getProtocol().equalsIgnoreCase("https")) {
-				return false;
-					}
-
-            String sUrlPath = url.getPath();
-			if (sUrlPath == null || sUrlPath.isEmpty()) {
+	public boolean fixCounterpart() {
+		Presences presences = conversation.getContact().getPresences();
+		if (counterpart != null && presences.has(counterpart.getResourcepart())) {
+			return true;
+		} else if (presences.size() >= 1) {
+			try {
+				counterpart = Jid.fromParts(conversation.getJid().getLocalpart(),
+						conversation.getJid().getDomainpart(),
+						presences.asStringArray()[0]);
+				return true;
+			} catch (InvalidJidException e) {
+				counterpart = null;
 				return false;
 			}
+		} else {
+			counterpart = null;
+			return false;
+		}
+	}
 
-            int iSlashIndex = sUrlPath.lastIndexOf('/') + 1;
+	public enum Decision {
+		MUST,
+		SHOULD,
+		NEVER,
+	}
 
-            String sLastUrlPath = sUrlPath.substring(iSlashIndex).toLowerCase();
+	private static String extractRelevantExtension(URL url) {
+		String path = url.getPath();
+		if (path == null || path.isEmpty()) {
+			return null;
+		}
+		String filename = path.substring(path.lastIndexOf('/') + 1).toLowerCase();
+		String[] extensionParts = filename.split("\\.");
+		if (extensionParts.length == 2) {
+			return extensionParts[extensionParts.length - 1];
+		} else if (extensionParts.length == 3 && Arrays
+				.asList(Transferable.VALID_CRYPTO_EXTENSIONS)
+				.contains(extensionParts[extensionParts.length - 1])) {
+			return extensionParts[extensionParts.length -2];
+		}
+		return null;
+	}
 
-			String[] extensionParts = sLastUrlPath.split("\\.");
-			if (extensionParts.length == 2
-					&& Arrays.asList(Downloadable.VALID_IMAGE_EXTENSIONS).contains(
-						extensionParts[extensionParts.length - 1])) {
-				return true;
-			} else if (extensionParts.length == 3
-					&& Arrays
-					.asList(Downloadable.VALID_CRYPTO_EXTENSIONS)
-					.contains(extensionParts[extensionParts.length - 1])
-					&& Arrays.asList(Downloadable.VALID_IMAGE_EXTENSIONS).contains(
-						extensionParts[extensionParts.length - 2])) {
-				return true;
+	public String getMimeType() {
+		if (relativeFilePath != null) {
+			int start = relativeFilePath.lastIndexOf('.') + 1;
+			if (start < relativeFilePath.length()) {
+				return MimeUtils.guessMimeTypeFromExtension(relativeFilePath.substring(start));
 			} else {
-				return false;
+				return null;
+			}
+		} else {
+			try {
+				return MimeUtils.guessMimeTypeFromExtension(extractRelevantExtension(new URL(body.trim())));
+			} catch (MalformedURLException e) {
+				return null;
 			}
+		}
+	}
+
+	public Decision treatAsDownloadable() {
+		if (body.trim().contains(" ")) {
+			return Decision.NEVER;
+		}
+		try {
+			URL url = new URL(body);
+			if (!url.getProtocol().equalsIgnoreCase("http") && !url.getProtocol().equalsIgnoreCase("https")) {
+				return Decision.NEVER;
+			}
+			String extension = extractRelevantExtension(url);
+			if (extension == null) {
+				return Decision.NEVER;
+			}
+			String ref = url.getRef();
+			boolean encrypted = ref != null && ref.matches("([A-Fa-f0-9]{2}){48}");
+
+			if (encrypted) {
+				if (MimeUtils.guessMimeTypeFromExtension(extension) != null) {
+					return Decision.MUST;
+				} else {
+					return Decision.NEVER;
+				}
+			} else if (Arrays.asList(Transferable.VALID_IMAGE_EXTENSIONS).contains(extension)
+					|| Arrays.asList(Transferable.WELL_KNOWN_EXTENSIONS).contains(extension)) {
+				return Decision.SHOULD;
+			} else {
+				return Decision.NEVER;
+			}
+
 		} catch (MalformedURLException e) {
-			return false;
+			return Decision.NEVER;
 		}
 	}
 
-	public ImageParams getImageParams() {
-		ImageParams params = getLegacyImageParams();
+	public boolean bodyIsHeart() {
+		return body != null && UIHelper.HEARTS.contains(body.trim());
+	}
+
+	public FileParams getFileParams() {
+		FileParams params = getLegacyFileParams();
 		if (params != null) {
 			return params;
 		}
-		params = new ImageParams();
-		if (this.downloadable != null) {
-			params.size = this.downloadable.getFileSize();
+		params = new FileParams();
+		if (this.transferable != null) {
+			params.size = this.transferable.getFileSize();
 		}
 		if (body == null) {
 			return params;
 		}
 		String parts[] = body.split("\\|");
-		if (parts.length == 1) {
-			try {
-				params.size = Long.parseLong(parts[0]);
-			} catch (NumberFormatException e) {
-				params.origin = parts[0];
+		switch (parts.length) {
+			case 1:
+				try {
+					params.size = Long.parseLong(parts[0]);
+				} catch (NumberFormatException e) {
+					try {
+						params.url = new URL(parts[0]);
+					} catch (MalformedURLException e1) {
+						params.url = null;
+					}
+				}
+				break;
+			case 2:
+			case 4:
 				try {
 					params.url = new URL(parts[0]);
 				} catch (MalformedURLException e1) {
 					params.url = null;
 				}
-			}
-		} else if (parts.length == 3) {
-			try {
-				params.size = Long.parseLong(parts[0]);
-			} catch (NumberFormatException e) {
-				params.size = 0;
-			}
-			try {
-				params.width = Integer.parseInt(parts[1]);
-			} catch (NumberFormatException e) {
-				params.width = 0;
-			}
-			try {
-				params.height = Integer.parseInt(parts[2]);
-			} catch (NumberFormatException e) {
-				params.height = 0;
-			}
-		} else if (parts.length == 4) {
-			params.origin = parts[0];
-			try {
-				params.url = new URL(parts[0]);
-			} catch (MalformedURLException e1) {
-				params.url = null;
-			}
-			try {
-				params.size = Long.parseLong(parts[1]);
-			} catch (NumberFormatException e) {
-				params.size = 0;
-			}
-			try {
-				params.width = Integer.parseInt(parts[2]);
-			} catch (NumberFormatException e) {
-				params.width = 0;
-			}
-			try {
-				params.height = Integer.parseInt(parts[3]);
-			} catch (NumberFormatException e) {
-				params.height = 0;
-			}
+				try {
+					params.size = Long.parseLong(parts[1]);
+				} catch (NumberFormatException e) {
+					params.size = 0;
+				}
+				try {
+					params.width = Integer.parseInt(parts[2]);
+				} catch (NumberFormatException | ArrayIndexOutOfBoundsException e) {
+					params.width = 0;
+				}
+				try {
+					params.height = Integer.parseInt(parts[3]);
+				} catch (NumberFormatException | ArrayIndexOutOfBoundsException e) {
+					params.height = 0;
+				}
+				break;
+			case 3:
+				try {
+					params.size = Long.parseLong(parts[0]);
+				} catch (NumberFormatException e) {
+					params.size = 0;
+				}
+				try {
+					params.width = Integer.parseInt(parts[1]);
+				} catch (NumberFormatException e) {
+					params.width = 0;
+				}
+				try {
+					params.height = Integer.parseInt(parts[2]);
+				} catch (NumberFormatException e) {
+					params.height = 0;
+				}
+				break;
 		}
 		return params;
 	}
 
-	public ImageParams getLegacyImageParams() {
-		ImageParams params = new ImageParams();
+	public FileParams getLegacyFileParams() {
+		FileParams params = new FileParams();
 		if (body == null) {
 			return params;
 		}
@@ -577,11 +649,18 @@ public class Message extends AbstractEntity {
 		return type == TYPE_FILE || type == TYPE_IMAGE;
 	}
 
-	public class ImageParams {
+	public boolean hasFileOnRemoteHost() {
+		return isFileOrImage() && getFileParams().url != null;
+	}
+
+	public boolean needsUploading() {
+		return isFileOrImage() && getFileParams().url == null;
+	}
+
+	public class FileParams {
 		public URL url;
 		public long size = 0;
 		public int width = 0;
 		public int height = 0;
-		public String origin;
 	}
 }
diff --git a/src/main/java/de/thedevstack/conversationsplus/entities/MucOptions.java b/src/main/java/de/thedevstack/conversationsplus/entities/MucOptions.java
index 860643e0..22155f3e 100644
--- a/src/main/java/de/thedevstack/conversationsplus/entities/MucOptions.java
+++ b/src/main/java/de/thedevstack/conversationsplus/entities/MucOptions.java
@@ -343,8 +343,6 @@ public class MucOptions {
 					setError(ERROR_BANNED);
 				} else if (error != null && error.hasChild("registration-required")) {
 					setError(ERROR_MEMBERS_ONLY);
-				} else {
-					setError(ERROR_UNKNOWN);
 				}
 			}
 		}
diff --git a/src/main/java/de/thedevstack/conversationsplus/entities/Roster.java b/src/main/java/de/thedevstack/conversationsplus/entities/Roster.java
index 0c719ed9..b1cb78b4 100644
--- a/src/main/java/de/thedevstack/conversationsplus/entities/Roster.java
+++ b/src/main/java/de/thedevstack/conversationsplus/entities/Roster.java
@@ -2,6 +2,7 @@ package de.thedevstack.conversationsplus.entities;
 
 import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.Iterator;
 import java.util.List;
 
 import de.thedevstack.conversationsplus.xmpp.jid.Jid;
@@ -55,12 +56,15 @@ public class Roster {
 		}
 	}
 
-	public void clearSystemAccounts() {
-		for (Contact contact : getContacts()) {
-			contact.setPhotoUri(null);
-			contact.setSystemName(null);
-			contact.setSystemAccount(null);
+	public List<Contact> getWithSystemAccounts() {
+		List<Contact> with = getContacts();
+		for(Iterator<Contact> iterator = with.iterator(); iterator.hasNext();) {
+			Contact contact = iterator.next();
+			if (contact.getSystemAccount() == null) {
+				iterator.remove();
+			}
 		}
+		return with;
 	}
 
 	public List<Contact> getContacts() {
@@ -70,6 +74,9 @@ public class Roster {
 	}
 
 	public void initContact(final Contact contact) {
+		if (contact == null) {
+			return;
+		}
 		contact.setAccount(account);
 		contact.setOption(Contact.Options.IN_ROSTER);
 		synchronized (this.contacts) {
diff --git a/src/main/java/de/thedevstack/conversationsplus/entities/Transferable.java b/src/main/java/de/thedevstack/conversationsplus/entities/Transferable.java
new file mode 100644
index 00000000..a5bdb5d7
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/entities/Transferable.java
@@ -0,0 +1,28 @@
+package de.thedevstack.conversationsplus.entities;
+
+public interface Transferable {
+
+	String[] VALID_IMAGE_EXTENSIONS = {"webp", "jpeg", "jpg", "png", "jpe"};
+	String[] VALID_CRYPTO_EXTENSIONS = {"pgp", "gpg", "otr"};
+	String[] WELL_KNOWN_EXTENSIONS = {"pdf","m4a"};
+
+	int STATUS_UNKNOWN = 0x200;
+	int STATUS_CHECKING = 0x201;
+	int STATUS_FAILED = 0x202;
+	int STATUS_OFFER = 0x203;
+	int STATUS_DOWNLOADING = 0x204;
+	int STATUS_DELETED = 0x205;
+	int STATUS_OFFER_CHECK_FILESIZE = 0x206;
+	int STATUS_UPLOADING = 0x207;
+
+
+	boolean start();
+
+	int getStatus();
+
+	long getFileSize();
+
+	int getProgress();
+
+	void cancel();
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/entities/DownloadablePlaceholder.java b/src/main/java/de/thedevstack/conversationsplus/entities/TransferablePlaceholder.java
index 741d2990..c51320d1 100644
--- a/src/main/java/de/thedevstack/conversationsplus/entities/DownloadablePlaceholder.java
+++ b/src/main/java/de/thedevstack/conversationsplus/entities/TransferablePlaceholder.java
@@ -1,10 +1,10 @@
 package de.thedevstack.conversationsplus.entities;
 
-public class DownloadablePlaceholder implements Downloadable {
+public class TransferablePlaceholder implements Transferable {
 
 	private int status;
 
-	public DownloadablePlaceholder(int status) {
+	public TransferablePlaceholder(int status) {
 		this.status = status;
 	}
 	@Override
@@ -28,11 +28,6 @@ public class DownloadablePlaceholder implements Downloadable {
 	}
 
 	@Override
-	public String getMimeType() {
-		return "";
-	}
-
-	@Override
 	public void cancel() {
 
 	}