[android] Create attachments before showing previews

briar-android/src/main/java/org/briarproject/briar/android/blog/ReblogFragment.java

 package org.briarproject.briar.android.blog;
 
-import android.net.Uri;
 import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -21,6 +20,7 @@ import org.briarproject.briar.android.fragment.BaseFragment;
 import org.briarproject.briar.android.view.TextInputView;
 import org.briarproject.briar.android.view.TextSendController;
 import org.briarproject.briar.android.view.TextSendController.SendListener;
+import org.briarproject.briar.api.messaging.AttachmentHeader;
 
 import java.util.List;
 
@@ -121,7 +121,8 @@ public class ReblogFragment extends BaseFragment implements SendListener {
 	}
 
 	@Override
-	public void onSendClick(@Nullable String text, List<Uri> imageUris) {
+	public void onSendClick(@Nullable String text,
+			List<AttachmentHeader> headers) {
 		ui.input.hideSoftKeyboard();
 		feedController.repeatPost(item, text,
 				new UiExceptionHandler<DbException>(this) {

briar-android/src/main/java/org/briarproject/briar/android/blog/WriteBlogPostActivity.java

 package org.briarproject.briar.android.blog;
 
 import android.content.Intent;
-import android.net.Uri;
 import android.os.Bundle;
 import android.support.annotation.Nullable;
 import android.view.KeyEvent;
@@ -27,6 +26,7 @@ import org.briarproject.briar.api.android.AndroidNotificationManager;
 import org.briarproject.briar.api.blog.BlogManager;
 import org.briarproject.briar.api.blog.BlogPost;
 import org.briarproject.briar.api.blog.BlogPostFactory;
+import org.briarproject.briar.api.messaging.AttachmentHeader;
 
 import java.security.GeneralSecurityException;
 import java.util.List;
@@ -120,7 +120,8 @@ public class WriteBlogPostActivity extends BriarActivity
 	}
 
 	@Override
-	public void onSendClick(@Nullable String text, List<Uri> imageUris) {
+	public void onSendClick(@Nullable String text,
+			List<AttachmentHeader> headers) {
 		if (isNullOrEmpty(text)) throw new AssertionError();
 
 		// hide publish button, show progress bar

briar-android/src/main/java/org/briarproject/briar/android/conversation/AttachmentController.java

 package org.briarproject.briar.android.conversation;
 
+import android.content.ContentResolver;
 import android.graphics.BitmapFactory;
 import android.graphics.BitmapFactory.Options;
+import android.net.Uri;
 import android.support.annotation.Nullable;
+import android.support.annotation.VisibleForTesting;
 import android.support.media.ExifInterface;
 import android.webkit.MimeTypeMap;
 
@@ -12,6 +15,7 @@ import org.briarproject.bramble.api.Pair;
 import org.briarproject.bramble.api.db.DatabaseExecutor;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.sync.GroupId;
 import org.briarproject.bramble.api.sync.MessageId;
 import org.briarproject.briar.android.conversation.ImageHelper.DecodeResult;
 import org.briarproject.briar.api.messaging.Attachment;
@@ -25,6 +29,7 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.logging.Logger;
 
 import static android.support.media.ExifInterface.ORIENTATION_ROTATE_270;
@@ -54,6 +59,7 @@ class AttachmentController {
 	private final int minWidth, maxWidth;
 	private final int minHeight, maxHeight;
 
+	private final List<AttachmentHeader> unsent = new CopyOnWriteArrayList<>();
 	private final Map<MessageId, List<AttachmentItem>> attachmentCache =
 			new ConcurrentHashMap<>();
 
@@ -114,6 +120,54 @@ class AttachmentController {
 		return attachments;
 	}
 
+	@DatabaseExecutor
+	AttachmentHeader createAttachmentHeader(ContentResolver contentResolver,
+			GroupId groupId, Uri uri)
+			throws IOException, DbException {
+		InputStream is = contentResolver.openInputStream(uri);
+		if (is == null) throw new IOException();
+		String contentType = contentResolver.getType(uri);
+		if (contentType == null) throw new IOException("null content type");
+		long timestamp = System.currentTimeMillis();
+		AttachmentHeader h = messagingManager
+				.addLocalAttachment(groupId, timestamp, contentType, is);
+		tryToClose(is, LOG, WARNING);
+		unsent.add(h);
+		return h;
+	}
+
+	@DatabaseExecutor
+	void deleteUnsentAttachments() {
+		for (AttachmentHeader h : unsent) {
+			try {
+				messagingManager.removeAttachment(h);
+			} catch (DbException e) {
+				logException(LOG, WARNING, e);
+			}
+		}
+	}
+
+	List<AttachmentHeader> getUnsentAttachments() {
+		return new ArrayList<>(unsent);
+	}
+
+	void markAttachmentsSent() {
+		unsent.clear();
+	}
+
+	@DatabaseExecutor
+	AttachmentItem getAttachmentItem(ContentResolver contentResolver, Uri uri,
+			AttachmentHeader h, boolean needsSize) throws IOException {
+		InputStream is = null;
+		try {
+			is = contentResolver.openInputStream(uri);
+			if (is == null) throw new IOException();
+			return getAttachmentItem(h, new Attachment(is), needsSize);
+		} finally {
+			if (is != null) tryToClose(is, LOG, WARNING);
+		}
+	}
+
 	/**
 	 * Creates {@link AttachmentItem}s from the passed headers and Attachments.
 	 * <p>
@@ -135,6 +189,7 @@ class AttachmentController {
 	 * Creates an {@link AttachmentItem} from the {@link Attachment}'s
 	 * {@link InputStream} which will be closed when this method returns.
 	 */
+	@VisibleForTesting
 	AttachmentItem getAttachmentItem(AttachmentHeader h, Attachment a,
 			boolean needsSize) {
 		MessageId messageId = h.getMessageId();

briar-android/src/main/java/org/briarproject/briar/android/conversation/ConversationActivity.java

@@ -6,7 +6,6 @@ import android.arch.lifecycle.ViewModelProvider;
 import android.arch.lifecycle.ViewModelProviders;
 import android.content.DialogInterface;
 import android.content.Intent;
-import android.net.Uri;
 import android.os.Bundle;
 import android.os.Parcelable;
 import android.support.annotation.Nullable;
@@ -264,7 +263,7 @@ public class ConversationActivity extends BriarActivity
 		if (FEATURE_FLAG_IMAGE_ATTACHMENTS) {
 			ImagePreview imagePreview = findViewById(R.id.imagePreview);
 			sendController = new TextAttachmentController(textInputView,
-					imagePreview, this, this);
+					imagePreview, this, this, viewModel);
 			observeOnce(viewModel.hasImageSupport(), this, hasSupport -> {
 				if (hasSupport != null && hasSupport) {
 					// remove cast when removing FEATURE_FLAG_IMAGE_ATTACHMENTS
@@ -658,12 +657,13 @@ public class ConversationActivity extends BriarActivity
 	}
 
 	@Override
-	public void onSendClick(@Nullable String text, List<Uri> imageUris) {
-		if (isNullOrEmpty(text) && imageUris.isEmpty())
+	public void onSendClick(@Nullable String text,
+			List<AttachmentHeader> attachmentHeaders) {
+		if (isNullOrEmpty(text) && attachmentHeaders.isEmpty())
 			throw new AssertionError();
 		long timestamp = System.currentTimeMillis();
 		timestamp = Math.max(timestamp, getMinTimestampForNewMessage());
-		viewModel.sendMessage(text, imageUris, timestamp);
+		viewModel.sendMessage(text, attachmentHeaders, timestamp);
 		textInputView.clearText();
 	}
 

briar-android/src/main/java/org/briarproject/briar/android/conversation/ConversationViewModel.java

@@ -11,7 +11,6 @@ import android.support.annotation.Nullable;
 import android.support.annotation.UiThread;
 
 import org.briarproject.bramble.api.FormatException;
-import org.briarproject.bramble.api.Pair;
 import org.briarproject.bramble.api.contact.Contact;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.contact.ContactManager;
@@ -27,10 +26,11 @@ import org.briarproject.bramble.api.settings.SettingsManager;
 import org.briarproject.bramble.api.sync.GroupId;
 import org.briarproject.bramble.api.sync.Message;
 import org.briarproject.bramble.api.sync.MessageId;
+import org.briarproject.bramble.api.system.AndroidExecutor;
 import org.briarproject.briar.android.util.UiUtils;
+import org.briarproject.briar.android.view.TextAttachmentController.AttachmentManager;
 import org.briarproject.briar.android.viewmodel.LiveEvent;
 import org.briarproject.briar.android.viewmodel.MutableLiveEvent;
-import org.briarproject.briar.api.messaging.Attachment;
 import org.briarproject.briar.api.messaging.AttachmentHeader;
 import org.briarproject.briar.api.messaging.MessagingManager;
 import org.briarproject.briar.api.messaging.PrivateMessage;
@@ -38,10 +38,11 @@ import org.briarproject.briar.api.messaging.PrivateMessageFactory;
 import org.briarproject.briar.api.messaging.PrivateMessageHeader;
 
 import java.io.IOException;
-import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.concurrent.Executor;
 import java.util.logging.Logger;
 
@@ -50,7 +51,6 @@ import javax.inject.Inject;
 import static java.util.Objects.requireNonNull;
 import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
-import static org.briarproject.bramble.util.IoUtils.tryToClose;
 import static org.briarproject.bramble.util.LogUtils.logDuration;
 import static org.briarproject.bramble.util.LogUtils.logException;
 import static org.briarproject.bramble.util.LogUtils.now;
@@ -59,7 +59,8 @@ import static org.briarproject.briar.android.settings.SettingsFragment.SETTINGS_
 import static org.briarproject.briar.android.util.UiUtils.observeForeverOnce;
 
 @NotNullByDefault
-public class ConversationViewModel extends AndroidViewModel {
+public class ConversationViewModel extends AndroidViewModel implements
+		AttachmentManager {
 
 	private static Logger LOG =
 			getLogger(ConversationViewModel.class.getName());
@@ -73,6 +74,7 @@ public class ConversationViewModel extends AndroidViewModel {
 	@CryptoExecutor
 	private final Executor cryptoExecutor;
 	private final TransactionManager db;
+	private final AndroidExecutor androidExecutor;
 	private final MessagingManager messagingManager;
 	private final ContactManager contactManager;
 	private final SettingsManager settingsManager;
@@ -100,17 +102,20 @@ public class ConversationViewModel extends AndroidViewModel {
 			new MutableLiveData<>();
 	private final MutableLiveData<PrivateMessageHeader> addedHeader =
 			new MutableLiveData<>();
+	// TODO move to AttachmentController
+	private final Map<Uri, AttachmentItem> unsentItems = new HashMap<>();
 
 	@Inject
 	ConversationViewModel(Application application,
 			@DatabaseExecutor Executor dbExecutor,
 			@CryptoExecutor Executor cryptoExecutor, TransactionManager db,
-			MessagingManager messagingManager, ContactManager contactManager,
-			SettingsManager settingsManager,
+			AndroidExecutor androidExecutor, MessagingManager messagingManager,
+			ContactManager contactManager, SettingsManager settingsManager,
 			PrivateMessageFactory privateMessageFactory) {
 		super(application);
 		this.dbExecutor = dbExecutor;
 		this.cryptoExecutor = cryptoExecutor;
+		this.androidExecutor = androidExecutor;
 		this.db = db;
 		this.messagingManager = messagingManager;
 		this.contactManager = contactManager;
@@ -121,6 +126,12 @@ public class ConversationViewModel extends AndroidViewModel {
 		contactDeleted.setValue(false);
 	}
 
+	@Override
+	protected void onCleared() {
+		super.onCleared();
+		attachmentController.deleteUnsentAttachments();
+	}
+
 	/**
 	 * Setting the {@link ContactId} automatically triggers loading of other
 	 * data.
@@ -176,15 +187,56 @@ public class ConversationViewModel extends AndroidViewModel {
 		});
 	}
 
-	void sendMessage(@Nullable String text, List<Uri> uris, long timestamp) {
+	void sendMessage(@Nullable String text,
+			List<AttachmentHeader> attachmentHeaders, long timestamp) {
 		if (messagingGroupId.getValue() == null) loadGroupId();
 		observeForeverOnce(messagingGroupId, groupId -> {
 			if (groupId == null) return;
-			// calls through to creating and storing the message
-			storeAttachments(groupId, text, uris, timestamp);
+			createMessage(groupId, text, attachmentHeaders, timestamp);
 		});
 	}
 
+	@Override
+	public void storeAttachment(Uri uri, boolean needsSize, Runnable onSuccess,
+			Runnable onError) {
+		if (unsentItems.containsKey(uri)) {
+			// This can happen due to configuration (screen orientation) change.
+			// So don't create a new attachment, if we have one already.
+			androidExecutor.runOnUiThread(onSuccess);
+			return;
+		}
+		if (messagingGroupId.getValue() == null) loadGroupId();
+		observeForeverOnce(messagingGroupId, groupId -> dbExecutor.execute(()
+				-> {
+			if (groupId == null) throw new IllegalStateException();
+			long start = now();
+			try {
+				ContentResolver contentResolver =
+						getApplication().getContentResolver();
+				AttachmentHeader h = attachmentController
+						.createAttachmentHeader(contentResolver, groupId, uri);
+				unsentItems.put(uri, attachmentController
+						.getAttachmentItem(contentResolver, uri, h, needsSize));
+				androidExecutor.runOnUiThread(onSuccess);
+			} catch (DbException | IOException e) {
+				logException(LOG, WARNING, e);
+				androidExecutor.runOnUiThread(onError);
+			}
+			logDuration(LOG, "Storing attachment", start);
+		}));
+	}
+
+	@Override
+	public List<AttachmentHeader> getAttachments() {
+		return attachmentController.getUnsentAttachments();
+	}
+
+	@Override
+	public void removeAttachments() {
+		unsentItems.clear();
+		dbExecutor.execute(attachmentController::deleteUnsentAttachments);
+	}
+
 	private void loadGroupId() {
 		if (contactId == null) throw new IllegalStateException();
 		dbExecutor.execute(() -> {
@@ -252,58 +304,8 @@ public class ConversationViewModel extends AndroidViewModel {
 		});
 	}
 
-	private void storeAttachments(GroupId groupId, @Nullable String text,
-			List<Uri> uris, long timestamp) {
-		dbExecutor.execute(() -> {
-			long start = now();
-			List<AttachmentHeader> attachments = new ArrayList<>();
-			List<AttachmentItem> items = new ArrayList<>();
-			boolean needsSize = uris.size() == 1;
-			for (Uri uri : uris) {
-				Pair<AttachmentHeader, AttachmentItem> pair =
-						createAttachmentHeader(groupId, uri, timestamp,
-								needsSize);
-				if (pair == null) continue;
-				attachments.add(pair.getFirst());
-				items.add(pair.getSecond());
-			}
-			logDuration(LOG, "Storing attachments", start);
-			createMessage(groupId, text, attachments, items, timestamp);
-		});
-	}
-
-	@Nullable
-	@DatabaseExecutor
-	private Pair<AttachmentHeader, AttachmentItem> createAttachmentHeader(
-			GroupId groupId, Uri uri, long timestamp, boolean needsSize) {
-		InputStream is = null;
-		try {
-			ContentResolver contentResolver =
-					getApplication().getContentResolver();
-			is = contentResolver.openInputStream(uri);
-			if (is == null) throw new IOException();
-			String contentType = contentResolver.getType(uri);
-			if (contentType == null) throw new IOException("null content type");
-			AttachmentHeader h = messagingManager
-					.addLocalAttachment(groupId, timestamp, contentType, is);
-			is.close();
-			// re-open stream to get AttachmentItem
-			is = contentResolver.openInputStream(uri);
-			if (is == null) throw new IOException();
-			AttachmentItem item = attachmentController
-					.getAttachmentItem(h, new Attachment(is), needsSize);
-			return new Pair<>(h, item);
-		} catch (DbException | IOException e) {
-			logException(LOG, WARNING, e);
-			return null;
-		} finally {
-			if (is != null) tryToClose(is, LOG, WARNING);
-		}
-	}
-
 	private void createMessage(GroupId groupId, @Nullable String text,
-			List<AttachmentHeader> attachments, List<AttachmentItem> aItems,
-			long timestamp) {
+			List<AttachmentHeader> attachments, long timestamp) {
 		cryptoExecutor.execute(() -> {
 			try {
 				// TODO remove when text can be null in the backend
@@ -311,7 +313,6 @@ public class ConversationViewModel extends AndroidViewModel {
 				PrivateMessage pm = privateMessageFactory
 						.createPrivateMessage(groupId, timestamp, msgText,
 								attachments);
-				attachmentController.put(pm.getMessage().getId(), aItems);
 				storeMessage(pm, msgText, attachments);
 			} catch (FormatException e) {
 				throw new RuntimeException(e);
@@ -331,6 +332,10 @@ public class ConversationViewModel extends AndroidViewModel {
 						message.getId(), message.getGroupId(),
 						message.getTimestamp(), true, true, false, false,
 						text != null, attachments);
+				attachmentController.put(m.getMessage().getId(),
+						new ArrayList<>(unsentItems.values()));
+				unsentItems.clear();
+				attachmentController.markAttachmentsSent();
 				// TODO add text to cache when available here
 				addedHeader.postValue(h);
 			} catch (DbException e) {

briar-android/src/main/java/org/briarproject/briar/android/introduction/IntroductionMessageFragment.java

 package org.briarproject.briar.android.introduction;
 
 import android.content.Context;
-import android.net.Uri;
 import android.os.Bundle;
 import android.support.annotation.Nullable;
 import android.support.v7.app.ActionBar;
@@ -26,6 +25,7 @@ import org.briarproject.briar.android.view.TextInputView;
 import org.briarproject.briar.android.view.TextSendController;
 import org.briarproject.briar.android.view.TextSendController.SendListener;
 import org.briarproject.briar.api.introduction.IntroductionManager;
+import org.briarproject.briar.api.messaging.AttachmentHeader;