Added automatic checks for missing messages in the database complete with download of these mesages.

src/main/java/de/fabianonline/telegram_backup/CommandLineDownloadProgress.java

@@ -31,7 +31,7 @@ class CommandLineDownloadProgress implements DownloadProgressInterface {
 	public void onMediaDownloadedEmpty(boolean n) { show(true, 'e'); }
 	public void onMediaDownloadFinished() { showNewLine(); System.out.println("Done."); }
 	
-	private void show(boolean n, char letter) { System.out.print(n ? letter : '.'); i++; if (i % 50 == 0) showNewLine();}
+	private void show(boolean n, char letter) { System.out.print(n ? letter : '.'); i++; if (i % 100 == 0) showNewLine();}
 	private void showNewLine() { System.out.println(" - " + i + "/" + mediaCount); }
 }
 	

src/main/java/de/fabianonline/telegram_backup/Database.java

@@ -14,6 +14,7 @@ import java.io.File;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.util.LinkedList;
+import java.sql.Array;
 
 import de.fabianonline.telegram_backup.UserManager;
 import de.fabianonline.telegram_backup.StickerConverter;
@@ -115,6 +116,42 @@ class Database {
 		}
 	}
 	
+	public int getMessageCount() {
+		try {
+			ResultSet rs = stmt.executeQuery("SELECT COUNT(*) FROM messages");
+			rs.next();
+			return rs.getInt(1);
+		} catch (SQLException e) {
+			throw new RuntimeException("Could not get count of messages.");
+		}
+	}
+	
+	public LinkedList<Integer> getMissingIDs() {
+		try {
+			LinkedList<Integer> missing = new LinkedList<Integer>();
+			int max = getTopMessageID();
+			ResultSet rs = stmt.executeQuery("SELECT id FROM messages ORDER BY id");
+			rs.next();
+			int id=rs.getInt(1);
+			for (int i=1; i<=max; i++) {
+				if (i==id) {
+					rs.next();
+					if (rs.isClosed()) {
+						id = Integer.MAX_VALUE;
+					} else {
+						id=rs.getInt(1);
+					}
+				} else if (i<id) {
+					missing.add(i);
+				}
+			}
+			return missing;
+		} catch(SQLException e) {
+			e.printStackTrace();
+			throw new RuntimeException("Could not get list of ids.");
+		}
+	}
+	
 	public void saveMessages(TLVector<TLAbsMessage> all) {
 		try {
 			PreparedStatement ps = conn.prepareStatement(

src/main/java/de/fabianonline/telegram_backup/DownloadManager.java

@@ -50,13 +50,14 @@ class DownloadManager {
 			System.out.println("New top message id 'in database' is " + max_database_id);
 		}
 		
+		if (max_database_id == max_message_id) {
+			System.out.println("No new messages to download.");
+		} else if (max_database_id > max_message_id) {
+			throw new RuntimeException("max_database_id is bigger then max_message_id. This shouldn't be aple to happen. Ever.");
+		} else {
 			int start_id = max_database_id + 1;
 			int current_start_id = start_id;
 			int end_id = max_message_id;
-		if (start_id > end_id) {
-			System.out.println("No new messages to download.");
-			return;
-		}
 			
 			prog.onMessageDownloadStart(end_id - current_start_id + 1);
 			
@@ -81,6 +82,28 @@ class DownloadManager {
 			prog.onMessageDownloadFinished();
 		}
 		
+		System.out.println("Checking message database for completeness...");
+		if (db.getMessageCount() != db.getTopMessageID()) {
+			LinkedList<Integer> ids = db.getMissingIDs();
+			System.out.println("Downloading " + ids.size() + " messages that are missing in your database.");
+			prog.onMessageDownloadStart(ids.size());
+			while (ids.size()>0) {
+				TLIntVector vector = new TLIntVector();
+				for (int i=0; i<100; i++) {
+					if (ids.size()==0) break;
+					vector.add(ids.remove());
+				}
+				TLAbsMessages response = client.messagesGetMessages(vector);
+				prog.onMessageDownloaded(response.getMessages().size());
+				db.saveMessages(response.getMessages());
+				db.saveChats(response.getChats());
+				db.saveUsers(response.getUsers());
+				try { Thread.sleep(Config.DELAY_AFTER_GET_MESSAGES); } catch (InterruptedException e) {}
+			}
+			prog.onMessageDownloadFinished();
+		}
+	}
+	
 	public void downloadMedia() throws RpcErrorException, IOException {
 		LinkedList<TLMessage> messages = this.db.getMessagesWithMedia();
 		prog.onMediaDownloadStart(messages.size());