content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.cassandra.schema;
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.Map;
  import java.util.Optional;
  import java.util.function.Predicate;
  import java.util.stream.Stream;
  import java.util.stream.StreamSupport;
  
  import javax.annotation.Nullable;
  
  import com.google.common.collect.*;
  
  import org.apache.cassandra.db.TypeSizes;
  import org.apache.cassandra.db.marshal.UserType;
  import org.apache.cassandra.index.internal.CassandraIndex;
  import org.apache.cassandra.io.util.DataInputPlus;
  import org.apache.cassandra.io.util.DataOutputPlus;
  import org.apache.cassandra.tcm.serialization.UDTAndFunctionsAwareMetadataSerializer;
  import org.apache.cassandra.tcm.serialization.Version;
  
  import static com.google.common.collect.Iterables.any;
  import static com.google.common.collect.Iterables.transform;
  
  /**
   * An immutable container for a keyspace's Tables.
   */
  public final class Tables implements Iterable<TableMetadata>
  {
      public static final Serializer serializer = new Serializer();
  
      private static final Tables NONE = builder().build();
  
      private final ImmutableMap<String, TableMetadata> tables;
      private final ImmutableMap<TableId, TableMetadata> tablesById;
      private final ImmutableMap<String, TableMetadata> indexTables;
  
      private Tables(Builder builder)
      {
          tables = builder.tables.build();
          tablesById = builder.tablesById.build();
          indexTables = builder.indexTables.build();
      }
  
      public static Builder builder()
      {
          return new Builder();
      }
  
      public static Tables none()
      {
          return NONE;
      }
  
      public static Tables of(TableMetadata... tables)
      {
          return builder().add(tables).build();
      }
  
      public static Tables of(Iterable<TableMetadata> tables)
      {
          return builder().add(tables).build();
      }
  
      public Iterator<TableMetadata> iterator()
      {
          return tables.values().iterator();
      }
  
      public Stream<TableMetadata> stream()
      {
          return StreamSupport.stream(spliterator(), false);
      }
  
      public Iterable<TableMetadata> referencingUserType(ByteBuffer name)
      {
          return Iterables.filter(tables.values(), t -> t.referencesUserType(name));
      }
  
      ImmutableMap<String, TableMetadata> indexTables()
      {
          return indexTables;
      }
  
      public int size()
      {
          return tables.size();
      }
  
      /**
       * Get the table with the specified name
       *
       * @param name a non-qualified table name
       * @return an empty {@link Optional} if the table name is not found; a non-empty optional of {@link TableMetadataRef} otherwise
       */
      public Optional<TableMetadata> get(String name)
      {
          return Optional.ofNullable(tables.get(name));
      }
  
      /**
       * Get the table with the specified name
       *
       * @param name a non-qualified table name
       * @return null if the table name is not found; the found {@link TableMetadataRef} otherwise
       */
      @Nullable
      public TableMetadata getNullable(String name)
      {
          return tables.get(name);
      }
  
      @Nullable
      public TableMetadata getNullable(TableId id)
      {
          return tablesById.get(id);
      }
  
      boolean containsTable(TableId id)
      {
          return tablesById.containsKey(id);
      }
  
      public Tables filter(Predicate<TableMetadata> predicate)
      {
          Builder builder = builder();
          tables.values().stream().filter(predicate).forEach(builder::add);
          return builder.build();
      }
  
      /**
       * Create a Tables instance with the provided table added
       */
      public Tables with(TableMetadata table)
      {
          if (get(table.name).isPresent())
              throw new IllegalStateException(String.format("Table %s already exists", table.name));
  
          return builder().add(this).add(table).build();
      }
  
      public Tables withSwapped(TableMetadata table)
      {
          return without(table.name).with(table);
      }
  
      /**
       * Creates a Tables instance with the table with the provided name removed
       */
      public Tables without(String name)
      {
          TableMetadata table =
              get(name).orElseThrow(() -> new IllegalStateException(String.format("Table %s doesn't exists", name)));
  
          return without(table);
      }
  
      public Tables without(TableMetadata table)
      {
          return filter(t -> t != table);
      }
  
      public Tables withUpdatedUserType(UserType udt)
      {
          return any(this, t -> t.referencesUserType(udt.name))
               ? builder().add(transform(this, t -> t.withUpdatedUserType(udt))).build()
               : this;
      }
  
      MapDifference<String, TableMetadata> indexesDiff(Tables other)
      {
          Map<String, TableMetadata> thisIndexTables = new HashMap<>();
          this.indexTables.values().forEach(t -> thisIndexTables.put(t.indexName().get(), t));
  
          Map<String, TableMetadata> otherIndexTables = new HashMap<>();
          other.indexTables.values().forEach(t -> otherIndexTables.put(t.indexName().get(), t));
  
          return Maps.difference(thisIndexTables, otherIndexTables);
      }
  
      @Override
      public boolean equals(Object o)
      {
          return this == o || (o instanceof Tables && tables.equals(((Tables) o).tables));
      }
  
      @Override
      public int hashCode()
      {
          return tables.hashCode();
      }
  
      @Override
      public String toString()
      {
          return tables.values().toString();
      }
  
      public static final class Builder
      {
          final ImmutableMap.Builder<String, TableMetadata> tables = new ImmutableMap.Builder<>();
          final ImmutableMap.Builder<TableId, TableMetadata> tablesById = new ImmutableMap.Builder<>();
          final ImmutableMap.Builder<String, TableMetadata> indexTables = new ImmutableMap.Builder<>();
  
          private Builder()
          {
          }
  
          public Tables build()
          {
              return new Tables(this);
          }
  
          public Builder add(TableMetadata table)
          {
              tables.put(table.name, table);
  
              tablesById.put(table.id, table);
  
              table.indexes
                   .stream()
                   .filter(i -> !i.isCustom())
                   .map(i -> CassandraIndex.indexCfsMetadata(table, i))
                   .forEach(i -> indexTables.put(i.indexName().get(), i));
  
              return this;
          }
  
          public Builder add(TableMetadata... tables)
          {
              for (TableMetadata table : tables)
                  add(table);
              return this;
          }
  
          public Builder add(Iterable<TableMetadata> tables)
          {
              tables.forEach(this::add);
              return this;
          }
      }
  
      static TablesDiff diff(Tables before, Tables after)
      {
          return TablesDiff.diff(before, after);
      }
  
      public static final class TablesDiff extends Diff<Tables, TableMetadata>
      {
          private final static TablesDiff NONE = new TablesDiff(Tables.none(), Tables.none(), ImmutableList.of());
  
          private TablesDiff(Tables created, Tables dropped, ImmutableCollection<Altered<TableMetadata>> altered)
          {
              super(created, dropped, altered);
          }
  
          private static TablesDiff diff(Tables before, Tables after)
          {
              if (before == after)
                  return NONE;
  
              Tables created = after.filter(t -> !before.containsTable(t.id));
              Tables dropped = before.filter(t -> !after.containsTable(t.id));
  
              ImmutableList.Builder<Altered<TableMetadata>> altered = ImmutableList.builder();
              before.forEach(tableBefore ->
              {
                  TableMetadata tableAfter = after.getNullable(tableBefore.id);
                  if (null != tableAfter)
                      tableBefore.compare(tableAfter).ifPresent(kind -> altered.add(new Altered<>(tableBefore, tableAfter, kind)));
              });
  
              return new TablesDiff(created, dropped, altered.build());
          }
      }
  
      public static class Serializer implements UDTAndFunctionsAwareMetadataSerializer<Tables>
      {
          public void serialize(Tables t, DataOutputPlus out, Version version) throws IOException
          {
              out.writeInt(t.tables.size());
              for (TableMetadata tm : t.tables.values())
                  TableMetadata.serializer.serialize(tm, out, version);
          }
  
          public Tables deserialize(DataInputPlus in, Types types, UserFunctions functions, Version version) throws IOException
          {
              int count = in.readInt();
              Tables.Builder builder = Tables.builder();
              for (int i = 0; i < count; i++)
              {
                  TableMetadata tm = TableMetadata.serializer.deserialize(in, types, functions, version);
                  builder.add(tm);
              }
              return builder.build();
          }
  
          public long serializedSize(Tables t, Version version)
          {
              int size = TypeSizes.sizeof(t.tables.size());
              for (TableMetadata tm : t.tables.values())
                  size += TableMetadata.serializer.serializedSize(tm, version);
              return size;
          }
      }
  }
  