Prevent computer dump command sending too much information

src/main/java/dan200/computercraft/shared/command/CommandComputerCraft.java

@@ -10,11 +10,13 @@ import net.minecraft.command.CommandException;
 import net.minecraft.command.ICommandSender;
 import net.minecraft.entity.Entity;
 import net.minecraft.entity.player.EntityPlayerMP;
+import net.minecraft.server.MinecraftServer;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.text.ITextComponent;
 import net.minecraft.world.World;
 
 import javax.annotation.Nonnull;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
@@ -48,8 +50,35 @@ public final class CommandComputerCraft extends CommandDelegate
                 {
                     TextTable table = new TextTable( "Instance", "Id", "On", "Position" );
 
-                    int max = 50;
+                    List<ServerComputer> computers = new ArrayList<>( ComputerCraft.serverComputerRegistry.getComputers() );
-                    for( ServerComputer computer : ComputerCraft.serverComputerRegistry.getComputers() )
+
+                    // Unless we're on a server, limit the number of rows we can send.
+                    if( !(context.getSender() instanceof MinecraftServer) )
+                    {
+                        World world = context.getSender().getEntityWorld();
+                        BlockPos pos = context.getSender().getPosition();
+
+                        computers.sort( ( a, b ) -> {
+                            if( a.getWorld() == b.getWorld() && a.getWorld() == world )
+                            {
+                                return Double.compare( a.getPosition().distanceSq( pos ), b.getPosition().distanceSq( pos ) );
+                            }
+                            else if( a.getWorld() == world )
+                            {
+                                return -1;
+                            }
+                            else if( b.getWorld() == world )
+                            {
+                                return 1;
+                            }
+                            else
+                            {
+                                return Integer.compare( a.getInstanceID(), b.getInstanceID() );
+                            }
+                        } );
+                    }
+
+                    for( ServerComputer computer : computers )
                     {
                         table.addRow(
                             linkComputer( computer ),
@@ -57,8 +86,6 @@ public final class CommandComputerCraft extends CommandDelegate
                             bool( computer.isOn() ),
                             linkPosition( context, computer )
                         );
-
-                        if( max-- < 0 ) break;
                     }
 
                     table.displayTo( context.getSender() );
@@ -202,13 +229,16 @@ public final class CommandComputerCraft extends CommandDelegate
             "view", "<id>", "View the terminal of a computer.", UserLevel.OP,
             "Open the terminal of a computer, allowing remote control of a computer. This does not provide access to " +
                 "turtle's inventories. You can either specify the computer's instance id (e.g. 123) or computer id (e.g #123)."
-        ) {
+        )
+        {
             @Override
-            public void execute(@Nonnull CommandContext context, @Nonnull List<String> arguments) throws CommandException {
+            public void execute( @Nonnull CommandContext context, @Nonnull List<String> arguments ) throws CommandException
+            {
                 if( arguments.size() != 1 ) throw new CommandException( context.getFullUsage() );
 
                 ICommandSender sender = context.getSender();
-                if (!(sender instanceof EntityPlayerMP)) {
+                if( !(sender instanceof EntityPlayerMP) )
+                {
                     throw new CommandException( "Cannot open terminal for non-player" );
                 }
 
@@ -218,7 +248,8 @@ public final class CommandComputerCraft extends CommandDelegate
 
             @Nonnull
             @Override
-            public List<String> getCompletion(@Nonnull CommandContext context, @Nonnull List<String> arguments) {
+            public List<String> getCompletion( @Nonnull CommandContext context, @Nonnull List<String> arguments )
+            {
                 return arguments.size() == 1
                     ? ComputerSelector.completeComputer( arguments.get( 0 ) )
                     : Collections.emptyList();

src/main/java/dan200/computercraft/shared/command/ComputerSelector.java

@@ -3,44 +3,28 @@ package dan200.computercraft.shared.command;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Sets;
 import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.core.ServerComputer;
 import net.minecraft.command.CommandException;
 
-import java.util.List;
+import java.util.*;
-import java.util.Set;
+import java.util.function.Predicate;
 
 public final class ComputerSelector
 {
-    public static ServerComputer getComputer( String selector ) throws CommandException
+    private static ServerComputer getComputer( Predicate<ServerComputer> predicate, String kind ) throws CommandException
     {
-        if( selector.length() > 0 && selector.charAt( 0 ) == '#' )
-        {
-            selector = selector.substring( 1 );
-
-            int id;
-            try
-            {
-                id = Integer.parseInt( selector );
-            }
-            catch( NumberFormatException e )
-            {
-                throw new CommandException( "'" + selector + "' is not a valid number" );
-            }
-
         // We copy it to prevent concurrent modifications.
         List<ServerComputer> computers = Lists.newArrayList( ComputerCraft.serverComputerRegistry.getComputers() );
         List<ServerComputer> candidates = Lists.newArrayList();
         for( ServerComputer searchComputer : computers )
         {
-                if( searchComputer.getID() == id )
+            if( predicate.test( searchComputer ) ) candidates.add( searchComputer );
-                {
-                    candidates.add( searchComputer );
-                }
         }
 
         if( candidates.size() == 0 )
         {
-                throw new CommandException( "No such computer for id " + id );
+            throw new CommandException( "No such computer for " + kind );
         }
         else if( candidates.size() == 1 )
         {
@@ -48,8 +32,8 @@ public final class ComputerSelector
         }
         else
         {
-                StringBuilder builder = new StringBuilder( "Multiple computers with id " )
+            StringBuilder builder = new StringBuilder( "Multiple computers with " )
-                    .append( id ).append( " (instances " );
+                .append( kind ).append( " (instances " );
 
             boolean first = true;
             for( ServerComputer computer : candidates )
@@ -71,6 +55,35 @@ public final class ComputerSelector
             throw new CommandException( builder.toString() );
         }
     }
+
+    public static ServerComputer getComputer( String selector ) throws CommandException
+    {
+        if( selector.length() > 0 && selector.charAt( 0 ) == '#' )
+        {
+            selector = selector.substring( 1 );
+
+            int id;
+            try
+            {
+                id = Integer.parseInt( selector );
+            }
+            catch( NumberFormatException e )
+            {
+                throw new CommandException( "'" + selector + "' is not a valid number" );
+            }
+
+            return getComputer( x -> x.getID() == id, "id " + id );
+        }
+        else if( selector.length() > 0 && selector.charAt( 0 ) == '@' )
+        {
+            String label = selector.substring( 1 );
+            return getComputer( x -> Objects.equals( label, x.getLabel() ), "label '" + label + "'" );
+        }
+        else if( selector.length() > 0 && selector.charAt( 0 ) == '~' )
+        {
+            String familyName = selector.substring( 1 );
+            return getComputer( x -> x.getFamily().name().equalsIgnoreCase( familyName ), "family '" + familyName + "'" );
+        }
         else
         {
             int instance;
@@ -97,7 +110,7 @@ public final class ComputerSelector
 
     public static List<String> completeComputer( String selector )
     {
-        Set<String> options = Sets.newHashSet();
+        TreeSet<String> options = Sets.newTreeSet();
 
         // We copy it to prevent concurrent modifications.
         List<ServerComputer> computers = Lists.newArrayList( ComputerCraft.serverComputerRegistry.getComputers() );
@@ -112,6 +125,26 @@ public final class ComputerSelector
                 if( id.startsWith( selector ) ) options.add( "#" + id );
             }
         }
+        else if( selector.length() > 0 && selector.charAt( 0 ) == '@' )
+        {
+            String label = selector.substring( 1 );
+            for( ServerComputer computer : computers )
+            {
+                String thisLabel = computer.getLabel();
+                if( thisLabel != null && thisLabel.startsWith( label ) ) options.add( "@" + thisLabel );
+            }
+        }
+        else if( selector.length() > 0 && selector.charAt( 0 ) == '~' )
+        {
+            String familyName = selector.substring( 1 ).toLowerCase( Locale.ENGLISH );
+            for( ComputerFamily family : ComputerFamily.values() )
+            {
+                if( family.name().toLowerCase( Locale.ENGLISH ).startsWith( familyName ) )
+                {
+                    options.add( "~" + family.name() );
+                }
+            }
+        }
         else
         {
             for( ServerComputer computer : computers )
@@ -121,6 +154,20 @@ public final class ComputerSelector
             }
         }
 
+        if( options.size() > 100 )
+        {
+            ArrayList<String> result = Lists.newArrayListWithCapacity( 100 );
+            for( String element : options )
+            {
+                if( result.size() > 100 ) break;
+                result.add( element );
+            }
+
+            return result;
+        }
+        else
+        {
             return Lists.newArrayList( options );
         }
     }
+}

src/main/java/dan200/computercraft/shared/command/framework/TextTable.java

@@ -148,8 +148,13 @@ public class TextTable
             }
         }
 
-        for( ITextComponent[] row : rows )
+        // Limit the number of rows to something sensible.
+        int limit = isPlayer( sender ) ? 30 : 100;
+        if( limit > rows.size() ) limit = rows.size();
+
+        for( int y = 0; y < limit; y++ )
         {
+            ITextComponent[] row = rows.get( y );
             for( int i = 0; i < row.length; i++ )
             {
                 int width = getWidth( row[i], sender );
@@ -190,7 +195,7 @@ public class TextTable
             out.appendSibling( LINE );
         }
 
-        for( int i = 0; i < rows.size(); i++ )
+        for( int i = 0; i < limit; i++ )
         {
             ITextComponent[] row = rows.get( i );
             if( i != 0 ) out.appendSibling( LINE );
@@ -201,6 +206,12 @@ public class TextTable
             }
         }
 
+        if( limit != rows.size() )
+        {
+            out.appendSibling( LINE );
+            out.appendSibling( coloured( (rows.size() - limit) + " additional rows...", TextFormatting.AQUA ) );
+        }
+
         sender.sendMessage( out );
     }