/**
* Computes the java String object hash code (32 bit) as the disaster ID of the message TODO: For
* security reasons (to prevent intentional hash collisions), this should be a cryptographic hash
* function instead of the string hash.
*
* @param cv
* @return
*/
private int getDisasterID(ContentValues cv) {
String text = cv.getAsString(DirectMessages.COL_TEXT);
String senderId;
if (!cv.containsKey(DirectMessages.COL_SENDER)
|| (cv.getAsString(DirectMessages.COL_SENDER) == null)) {
senderId = LoginActivity.getTwitterId(getContext()).toString();
} else {
senderId = cv.getAsString(DirectMessages.COL_SENDER);
}
return (new String(text + senderId)).hashCode();
}
/** Insert a direct message into the DB */
@Override
public synchronized Uri insert(Uri uri, ContentValues values) {
int disasterId;
Cursor c = null;
Uri insertUri = null; // the return value;
switch (dmUriMatcher.match(uri)) {
case LIST_NORMAL:
Log.d(TAG, "Insert LIST_NORMAL");
/*
* First, we check if we already have a direct messages with the
* same disaster ID. If yes, two cases are possible 1 If the
* existing message is a message of our own which was flagged to
* insert, the insert operation may have been successful but the
* success was not registered locally. In this case we update the
* new message with the new information 2 It may be a hash function
* collision (two different messages have the same hash code)
* Probability of this should be small.
*/
disasterId = getDisasterID(values);
c =
database.query(
DBOpenHelper.TABLE_DMS,
null,
DirectMessages.COL_DISASTERID + "=" + disasterId,
null,
null,
null,
null);
if (c.getCount() > 0) {
c.moveToFirst();
while (!c.isAfterLast()) {
boolean isOurs =
Long.toString(c.getLong(c.getColumnIndex(DirectMessages.COL_SENDER)))
.equals(LoginActivity.getTwitterId(getContext()));
boolean isForUs =
Long.toString(c.getLong(c.getColumnIndex(DirectMessages.COL_RECEIVER)))
.equals(LoginActivity.getTwitterId(getContext()));
if (isOurs || isForUs) {
// clear the to insert flag
int flags = c.getInt(c.getColumnIndex(DirectMessages.COL_FLAGS));
values.put(DirectMessages.COL_FLAGS, flags & (~DirectMessages.FLAG_TO_INSERT));
Uri updateUri =
Uri.parse(
"content://"
+ DirectMessages.DM_AUTHORITY
+ "/"
+ DirectMessages.DMS
+ "/"
+ Integer.toString(c.getInt(c.getColumnIndex("_id"))));
update(updateUri, values, null, null);
return updateUri;
}
c.moveToNext();
}
}
c.close();
// if none of the before was true, this is a proper new tweet which
// we now insert
insertUri = insertDM(values);
// delete everything that now falls out of the buffer
purgeDMs(values);
break;
case LIST_DISASTER:
Log.d(TAG, "Insert LIST_DISASTER");
// in disaster mode, we set the is disaster flag, encrypt and sign
// the message
// and sign the tweet (if we have a certificate for our key pair)
values.put(DirectMessages.COL_ISDISASTER, 1);
// if we already have a disaster tweet with the same disaster ID,
// we discard the new one
disasterId = getDisasterID(values);
c =
database.query(
DBOpenHelper.TABLE_DMS,
null,
DirectMessages.COL_DISASTERID
+ "="
+ disasterId
+ " AND "
+ DirectMessages.COL_ISDISASTER
+ ">0",
null,
null,
null,
null);
if (c.getCount() > 0) {
c.moveToFirst();
Uri oldUri =
Uri.parse(
"content://"
+ DirectMessages.DM_AUTHORITY
+ "/"
+ DirectMessages.DMS
+ "/"
+ Long.toString(c.getLong(c.getColumnIndex("_id"))));
c.close();
return oldUri;
}
CertificateManager cm = new CertificateManager(getContext());
KeyManager km = new KeyManager(getContext().getApplicationContext());
// verify whether I was the author or not
if (LoginActivity.getTwitterId(getContext())
.equals(values.getAsInteger(DirectMessages.COL_SENDER).toString())) {
if (cm.hasCertificate()) {
// we put the signature
String text = values.getAsString(DirectMessages.COL_TEXT);
String userId = LoginActivity.getTwitterId(getContext()).toString();
String signature = km.getSignature(new String(text + userId));
values.put(DirectMessages.COL_SIGNATURE, signature);
// and the certificate
values.put(DirectMessages.COL_CERTIFICATE, cm.getCertificate());
// and set the is_verified flag to show that the tweet is
// signed
values.put(DirectMessages.COL_ISVERIFIED, 1);
// Long twitterId =
// getIdFromScreenName(values.getAsString(DirectMessages.COL_RECEIVER_SCREENNAME));
// TODO: obtain peers public keys and encrypt
values.put(DirectMessages.COL_CRYPTEXT, text);
/*
* if (twitterId != null) { String cipherText =
* km.encrypt(text,twitterId ); Log.i(TAG, "ciphertext: " +
* cipherText ); if (cipherText != null) {
* values.put(DirectMessages.COL_CRYPTEXT,cipherText );
*
* } }
*/
} else values.put(DirectMessages.COL_ISVERIFIED, 0);
} else {
// Is it for me?
if (values
.getAsLong(DirectMessages.COL_RECEIVER)
.toString()
.equals(LoginActivity.getTwitterId(getContext()))) {
values.put(
DirectMessages.COL_BUFFER,
DirectMessages.BUFFER_DISASTER_ME | DirectMessages.BUFFER_MESSAGES);
// TODO: DECRYPT THE MESSAGE
// String plainText =
// km.decrypt(values.getAsString(DirectMessages.COL_CRYPTEXT));
String plainText = values.getAsString(DirectMessages.COL_CRYPTEXT);
// values.remove(DirectMessages.COL_CRYPTEXT);
values.put(DirectMessages.COL_TEXT, plainText);
// check signature
String signature = values.getAsString(DirectMessages.COL_SIGNATURE);
String certificate = values.getAsString(DirectMessages.COL_CERTIFICATE);
String textForSignatureCheck =
plainText + values.getAsString(DirectMessages.COL_SENDER);
if (km.checkSignature(cm.parsePem(certificate), signature, textForSignatureCheck)) {
values.put(DirectMessages.COL_ISVERIFIED, 1);
} else values.put(DirectMessages.COL_ISVERIFIED, 0);
} else values.put(DirectMessages.COL_BUFFER, DirectMessages.BUFFER_DISASTER_OTHERS);
}
c.close();
insertUri = insertDM(values);
// purgeTweets(values);
break;
default:
throw new IllegalArgumentException("Unsupported URI: " + uri);
}
return insertUri;
}
/** Query the direct messages table TODO: Create the queries more elegantly.. */
@Override
public synchronized Cursor query(
Uri uri, String[] projection, String where, String[] whereArgs, String sortOrder) {
if (TextUtils.isEmpty(sortOrder)) sortOrder = Tweets.DEFAULT_SORT_ORDER;
Cursor c = null;
String sql = null;
Intent i = null;
switch (dmUriMatcher.match(uri)) {
case DMS:
Log.d(TAG, "Query DMS");
c =
database.query(
DBOpenHelper.TABLE_DMS, projection, where, whereArgs, null, null, sortOrder);
c.setNotificationUri(getContext().getContentResolver(), DirectMessages.CONTENT_URI);
break;
case DM_ID:
Log.d(TAG, "Query DM_ID");
sql =
"SELECT * "
+ "FROM "
+ DBOpenHelper.TABLE_DMS
+ " "
+ "WHERE "
+ DBOpenHelper.TABLE_DMS
+ "._id="
+ uri.getLastPathSegment()
+ ";";
c = database.rawQuery(sql, null);
c.setNotificationUri(getContext().getContentResolver(), uri);
break;
case USER:
Log.d(TAG, "Query USER");
// get the twitter user id
sql =
"SELECT "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_TWITTER_USER_ID
+ " "
+ "FROM "
+ DBOpenHelper.TABLE_USERS
+ " "
+ "WHERE "
+ TwitterUsers.COL_ROW_ID
+ "="
+ uri.getLastPathSegment()
+ ";";
c = database.rawQuery(sql, null);
if (c.getCount() == 0) return null; // this should not happen
c.moveToFirst();
long twitterUserId = c.getLong(c.getColumnIndex(TwitterUsers.COL_TWITTER_USER_ID));
c.close();
// get the direct messages
sql =
"SELECT "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_ROW_ID
+ ", "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_TEXT
+ ", "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_SENDER
+ ", "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_CREATED
+ ", "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_ISDISASTER
+ ", "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_FLAGS
+ ", "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_DMID
+ ", "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_ROW_ID
+ " AS "
+ COL_USER_ROW_ID
+ ", "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_SCREEN_NAME
+ ", "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_NAME
+ ", "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_PROFILE_IMAGE_URI
+ " FROM "
+ DBOpenHelper.TABLE_DMS
+ " "
+ "JOIN "
+ DBOpenHelper.TABLE_USERS
+ " "
+ "ON "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_SENDER
+ "="
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_TWITTER_USER_ID
+ " "
+ "WHERE "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_RECEIVER
+ "="
+ twitterUserId
+ " "
+ "OR "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_SENDER
+ "="
+ twitterUserId
+ " "
+ "ORDER BY "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_CREATED
+ " DESC "
+ "LIMIT 100";
c = database.rawQuery(sql, null);
// TODO: Correct notification URI
c.setNotificationUri(getContext().getContentResolver(), DirectMessages.CONTENT_URI);
break;
case USERS:
Log.d(TAG, "Query USERS");
// selects the last DM of which the given user is either a sender or
// recepient
String subQuery1 =
"SELECT "
+ DirectMessages.COL_TEXT
+ " "
+ "FROM "
+ DBOpenHelper.TABLE_DMS
+ " "
+ "WHERE "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_RECEIVER
+ "="
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_TWITTER_USER_ID
+ " "
+ "OR "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_SENDER
+ "="
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_TWITTER_USER_ID
+ " "
+ "ORDER BY "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_CREATED
+ " DESC "
+ "LIMIT 1";
// selects the timestamp of the last DM of which the given user is
// either a sender or recepient
String subQuery2 =
"SELECT "
+ DirectMessages.COL_CREATED
+ " "
+ "FROM "
+ DBOpenHelper.TABLE_DMS
+ " "
+ "WHERE "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_RECEIVER
+ "="
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_TWITTER_USER_ID
+ " "
+ "OR "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_SENDER
+ "="
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_TWITTER_USER_ID
+ " "
+ "ORDER BY "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_CREATED
+ " DESC "
+ "LIMIT 1";
// selects all users who have sent or received at least one DM
sql =
"select "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_ROW_ID
+ ", "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_TWITTER_USER_ID
+ ", "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_SCREEN_NAME
+ ", "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_NAME
+ ", "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_PROFILE_IMAGE_URI
+ ", "
+ "("
+ subQuery1
+ ") AS text, "
+ "("
+ subQuery2
+ ") AS created "
+ "FROM "
+ DBOpenHelper.TABLE_USERS
+ " "
+ "LEFT JOIN "
+ DBOpenHelper.TABLE_DMS
+ " AS sent ON "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_TWITTER_USER_ID
+ "=sent."
+ DirectMessages.COL_SENDER
+ " "
+ "LEFT JOIN "
+ DBOpenHelper.TABLE_DMS
+ " AS received ON "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_TWITTER_USER_ID
+ "=received."
+ DirectMessages.COL_RECEIVER
+ " "
+ "WHERE "
+ "(sent."
+ DirectMessages.COL_TEXT
+ " IS NOT NULL OR "
+ "received."
+ DirectMessages.COL_TEXT
+ " IS NOT NULL) "
+ "AND "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_TWITTER_USER_ID
+ "<>"
+ LoginActivity.getTwitterId(getContext())
+ " "
+ "GROUP BY "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_TWITTER_USER_ID
+ " "
+ "ORDER BY created DESC LIMIT 100;";
Log.e(TAG, sql);
c = database.rawQuery(sql, null);
// TODO: Correct notification URI
c.setNotificationUri(getContext().getContentResolver(), DirectMessages.CONTENT_URI);
// start synch service with a synch DMs request
i = new Intent(getContext(), TwitterSyncService.class);
i.putExtra(
TwitterSyncService.EXTRA_KEY_ACTION, TwitterSyncService.EXTRA_ACTION_SYNC_MESSAGES);
getContext().startService(i);
break;
case LIST_ALL:
// TODO
break;
case LIST_DISASTER:
Log.i(TAG, "Query DMS Disaster");
c =
database.query(
DBOpenHelper.TABLE_DMS,
projection,
DirectMessages.COL_BUFFER
+ "&"
+ DirectMessages.BUFFER_MYDISASTER
+ "!=0"
+ " OR "
+ DirectMessages.COL_BUFFER
+ "&"
+ DirectMessages.BUFFER_DISASTER_OTHERS
+ "!=0",
whereArgs,
null,
null,
sortOrder);
c.setNotificationUri(getContext().getContentResolver(), DirectMessages.CONTENT_URI);
break;
case LIST_NORMAL:
// TODO
break;
case INCOMING_RECEIVED_AFTER:
Log.d(TAG, "Query INCOMING_RECEIVED_AFTER");
sql =
"SELECT "
+ DBOpenHelper.TABLE_DMS
+ "._id, "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_TEXT
+ ", "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_SENDER
+ ", "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_CREATED
+ ", "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_ISDISASTER
+ ", "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_FLAGS
+ ", "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_DMID
+ ", "
+ DBOpenHelper.TABLE_USERS
+ "._id AS "
+ COL_USER_ROW_ID
+ ", "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_SCREEN_NAME
+ ", "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_NAME
+ ", "
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_PROFILE_IMAGE_URI
+ " "
+ "FROM "
+ DBOpenHelper.TABLE_DMS
+ " "
+ "JOIN "
+ DBOpenHelper.TABLE_USERS
+ " "
+ "ON "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_SENDER
+ "="
+ DBOpenHelper.TABLE_USERS
+ "."
+ TwitterUsers.COL_TWITTER_USER_ID
+ " "
+ "WHERE "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_RECEIVER
+ "=="
+ LoginActivity.getTwitterId(getContext())
+ " AND "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_RECEIVED
+ ">"
+ uri.getLastPathSegment()
+ " "
+ "ORDER BY "
+ DBOpenHelper.TABLE_DMS
+ "."
+ DirectMessages.COL_CREATED
+ " DESC "
+ "LIMIT 100";
c = database.rawQuery(sql, null);
// TODO: Correct notification URI
c.setNotificationUri(getContext().getContentResolver(), DirectMessages.CONTENT_URI);
break;
default:
throw new IllegalArgumentException("Unsupported URI: " + uri);
}
return c;
}
