/*
    * 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.shardingsphere.infra.metadata.database.schema.reviser;
  
  import lombok.RequiredArgsConstructor;
  import org.apache.shardingsphere.infra.database.core.metadata.data.model.ColumnMetaData;
  import org.apache.shardingsphere.infra.database.core.metadata.data.model.ConstraintMetaData;
  import org.apache.shardingsphere.infra.database.core.metadata.data.model.IndexMetaData;
  import org.apache.shardingsphere.infra.database.core.metadata.data.model.SchemaMetaData;
  import org.apache.shardingsphere.infra.database.core.metadata.data.model.TableMetaData;
  import org.apache.shardingsphere.infra.metadata.database.schema.builder.GenericSchemaBuilderMaterial;
  import org.apache.shardingsphere.infra.metadata.database.schema.model.ShardingSphereColumn;
  import org.apache.shardingsphere.infra.metadata.database.schema.model.ShardingSphereConstraint;
  import org.apache.shardingsphere.infra.metadata.database.schema.model.ShardingSphereIndex;
  import org.apache.shardingsphere.infra.metadata.database.schema.model.ShardingSphereSchema;
  import org.apache.shardingsphere.infra.metadata.database.schema.model.ShardingSphereTable;
  import org.apache.shardingsphere.infra.metadata.database.schema.reviser.schema.SchemaMetaDataReviseEngine;
  import org.apache.shardingsphere.infra.rule.ShardingSphereRule;
  
  import java.util.Collection;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.LinkedList;
  import java.util.Map;
  import java.util.Map.Entry;
  import java.util.stream.Collectors;
  
  /**
   * Meta data revise engine.
   */
  @RequiredArgsConstructor
  public final class MetaDataReviseEngine {
      
      private final Collection<ShardingSphereRule> rules;
      
      /**
       * Revise meta data.
       *
       * @param schemaMetaDataMap schema meta data map
       * @param material generic schema builder material
       * @return ShardingSphere schema map
       */
      public Map<String, ShardingSphereSchema> revise(final Map<String, SchemaMetaData> schemaMetaDataMap, final GenericSchemaBuilderMaterial material) {
          if (schemaMetaDataMap.isEmpty()) {
              return Collections.singletonMap(material.getDefaultSchemaName(), new ShardingSphereSchema(material.getDefaultSchemaName()));
          }
          Map<String, ShardingSphereSchema> result = new HashMap<>(schemaMetaDataMap.size(), 1F);
          for (Entry<String, SchemaMetaData> entry : schemaMetaDataMap.entrySet()) {
              SchemaMetaData schemaMetaData = new SchemaMetaDataReviseEngine(rules, material.getProps()).revise(entry.getValue());
              result.put(entry.getKey(), new ShardingSphereSchema(entry.getKey(), convertToTables(schemaMetaData.getTables()), new LinkedList<>()));
          }
          return result;
      }
      
      private Collection<ShardingSphereTable> convertToTables(final Collection<TableMetaData> tableMetaDataList) {
          return tableMetaDataList.stream().map(each -> new ShardingSphereTable(
                  each.getName(), convertToColumns(each.getColumns()), convertToIndexes(each.getIndexes()), convertToConstraints(each.getConstraints()), each.getType())).collect(Collectors.toList());
      }
      
      private Collection<ShardingSphereColumn> convertToColumns(final Collection<ColumnMetaData> columnMetaDataList) {
          return columnMetaDataList.stream().map(ShardingSphereColumn::new).collect(Collectors.toList());
      }
      
      private Collection<ShardingSphereIndex> convertToIndexes(final Collection<IndexMetaData> indexMetaDataList) {
          return indexMetaDataList.stream().map(ShardingSphereIndex::new).collect(Collectors.toList());
      }
      
      private Collection<ShardingSphereConstraint> convertToConstraints(final Collection<ConstraintMetaData> constraintMetaDataList) {
          return constraintMetaDataList.stream().map(ShardingSphereConstraint::new).collect(Collectors.toList());
      }
  }