/*
    * 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;
  
  import lombok.Getter;
  import org.apache.shardingsphere.infra.config.database.DatabaseConfiguration;
  import org.apache.shardingsphere.infra.config.database.impl.DataSourceProvidedDatabaseConfiguration;
  import org.apache.shardingsphere.infra.config.props.ConfigurationProperties;
  import org.apache.shardingsphere.infra.config.rule.RuleConfiguration;
  import org.apache.shardingsphere.infra.database.core.type.DatabaseType;
  import org.apache.shardingsphere.infra.database.core.type.DatabaseTypeRegistry;
  import org.apache.shardingsphere.infra.instance.InstanceContext;
  import org.apache.shardingsphere.infra.metadata.database.resource.ResourceMetaData;
  import org.apache.shardingsphere.infra.metadata.database.resource.node.StorageNode;
  import org.apache.shardingsphere.infra.metadata.database.resource.unit.StorageUnit;
  import org.apache.shardingsphere.infra.metadata.database.rule.RuleMetaData;
  import org.apache.shardingsphere.infra.metadata.database.schema.builder.GenericSchemaBuilder;
  import org.apache.shardingsphere.infra.metadata.database.schema.builder.GenericSchemaBuilderMaterial;
  import org.apache.shardingsphere.infra.metadata.database.schema.builder.SystemSchemaBuilder;
  import org.apache.shardingsphere.infra.metadata.database.schema.model.ShardingSphereSchema;
  import org.apache.shardingsphere.infra.rule.ShardingSphereRule;
  import org.apache.shardingsphere.infra.rule.builder.database.DatabaseRulesBuilder;
  import org.apache.shardingsphere.infra.rule.attribute.datanode.MutableDataNodeRuleAttribute;
  import org.apache.shardingsphere.infra.state.datasource.DataSourceStateManager;
  
  import javax.sql.DataSource;
  import java.sql.SQLException;
  import java.util.Collection;
  import java.util.LinkedHashMap;
  import java.util.LinkedList;
  import java.util.Map;
  import java.util.Map.Entry;
  import java.util.concurrent.ConcurrentHashMap;
  import java.util.stream.Collectors;
  
  /**
   * ShardingSphere database.
   */
  @Getter
  public final class ShardingSphereDatabase {
      
      private final String name;
      
      private final DatabaseType protocolType;
      
      private final ResourceMetaData resourceMetaData;
      
      private final RuleMetaData ruleMetaData;
      
      private final Map<String, ShardingSphereSchema> schemas;
      
      public ShardingSphereDatabase(final String name, final DatabaseType protocolType, final ResourceMetaData resourceMetaData,
                                    final RuleMetaData ruleMetaData, final Map<String, ShardingSphereSchema> schemas) {
          this.name = name;
          this.protocolType = protocolType;
          this.resourceMetaData = resourceMetaData;
          this.ruleMetaData = ruleMetaData;
          this.schemas = new ConcurrentHashMap<>(schemas.size(), 1F);
          schemas.forEach((key, value) -> this.schemas.put(key.toLowerCase(), value));
      }
      
      /**
       * Create database meta data.
       * 
       * @param name database name
       * @param protocolType database protocol type
       * @param storageTypes storage types
       * @param databaseConfig database configuration
       * @param props configuration properties
       * @param instanceContext instance context
       * @return database meta data
       * @throws SQLException SQL exception
       */
      public static ShardingSphereDatabase create(final String name, final DatabaseType protocolType, final Map<String, DatabaseType> storageTypes,
                                                  final DatabaseConfiguration databaseConfig, final ConfigurationProperties props, final InstanceContext instanceContext) throws SQLException {
          Collection<ShardingSphereRule> databaseRules = DatabaseRulesBuilder.build(name, protocolType, databaseConfig, instanceContext);
          Map<String, ShardingSphereSchema> schemas = new ConcurrentHashMap<>(GenericSchemaBuilder
                  .build(new GenericSchemaBuilderMaterial(protocolType, storageTypes, DataSourceStateManager.getInstance().getEnabledDataSources(name, databaseConfig), databaseRules,
                          props, new DatabaseTypeRegistry(protocolType).getDefaultSchemaName(name))));
          SystemSchemaBuilder.build(name, protocolType, props).forEach(schemas::putIfAbsent);
          return create(name, protocolType, databaseConfig, databaseRules, schemas);
      }
      
      /**
      * Create system database meta data.
      * 
      * @param name system database name
      * @param protocolType protocol database type
      * @param props configuration properties
      * @return system database meta data
      */
     public static ShardingSphereDatabase create(final String name, final DatabaseType protocolType, final ConfigurationProperties props) {
         DatabaseConfiguration databaseConfig = new DataSourceProvidedDatabaseConfiguration(new LinkedHashMap<>(), new LinkedList<>());
         return create(name, protocolType, databaseConfig, new LinkedList<>(), SystemSchemaBuilder.build(name, protocolType, props));
     }
     
     /**
      * Create database meta data.
      *
      * @param name database name
      * @param protocolType database protocol type
      * @param databaseConfig database configuration
      * @param rules rules
      * @param schemas schemas
      * @return database meta data
      */
     public static ShardingSphereDatabase create(final String name, final DatabaseType protocolType, final DatabaseConfiguration databaseConfig,
                                                 final Collection<ShardingSphereRule> rules, final Map<String, ShardingSphereSchema> schemas) {
         ResourceMetaData resourceMetaData = createResourceMetaData(databaseConfig.getDataSources(), databaseConfig.getStorageUnits());
         RuleMetaData ruleMetaData = new RuleMetaData(rules);
         return new ShardingSphereDatabase(name, protocolType, resourceMetaData, ruleMetaData, schemas);
     }
     
     private static ResourceMetaData createResourceMetaData(final Map<StorageNode, DataSource> dataSources, final Map<String, StorageUnit> storageUnits) {
         return new ResourceMetaData(dataSources, storageUnits);
     }
     
     /**
      * Judge contains schema from database or not.
      *
      * @param schemaName schema name
      * @return contains schema from database or not
      */
     public boolean containsSchema(final String schemaName) {
         return schemas.containsKey(schemaName.toLowerCase());
     }
     
     /**
      * Get schema.
      *
      * @param schemaName schema name
      * @return schema
      */
     public ShardingSphereSchema getSchema(final String schemaName) {
         return schemas.get(schemaName.toLowerCase());
     }
     
     /**
      * Add schema.
      *
      * @param schemaName schema name
      * @param schema schema
      */
     public void addSchema(final String schemaName, final ShardingSphereSchema schema) {
         schemas.put(schemaName.toLowerCase(), schema);
     }
     
     /**
      * Drop schema.
      *
      * @param schemaName schema name
      */
     public void dropSchema(final String schemaName) {
         schemas.remove(schemaName.toLowerCase());
     }
     
     /**
      * Judge whether is completed.
      *
      * @return is completed or not
      */
     public boolean isComplete() {
         return !ruleMetaData.getRules().isEmpty() && !resourceMetaData.getStorageUnits().isEmpty();
     }
     
     /**
      * Judge whether contains data source.
      *
      * @return contains data source or not
      */
     public boolean containsDataSource() {
         return !resourceMetaData.getStorageUnits().isEmpty();
     }
     
     /**
      * Reload rules.
      */
     public synchronized void reloadRules() {
         Collection<ShardingSphereRule> toBeReloadedRules = ruleMetaData.getRules().stream()
                 .filter(each -> each.getAttributes().findAttribute(MutableDataNodeRuleAttribute.class).isPresent()).collect(Collectors.toList());
         RuleConfiguration ruleConfig = toBeReloadedRules.stream().map(ShardingSphereRule::getConfiguration).findFirst().orElse(null);
         Collection<ShardingSphereRule> rules = new LinkedList<>(ruleMetaData.getRules());
         toBeReloadedRules.stream().findFirst().ifPresent(optional -> {
             rules.removeAll(toBeReloadedRules);
             Map<String, DataSource> dataSources = resourceMetaData.getStorageUnits().entrySet().stream()
                     .collect(Collectors.toMap(Entry::getKey, entry -> entry.getValue().getDataSource(), (oldValue, currentValue) -> oldValue, LinkedHashMap::new));
             rules.add(optional.getAttributes().getAttribute(MutableDataNodeRuleAttribute.class).reloadRule(ruleConfig, name, dataSources, rules));
         });
         ruleMetaData.getRules().clear();
         ruleMetaData.getRules().addAll(rules);
     }
 }