/*
    * 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.data.pipeline.core.sqlbuilder.sql;
  
  import org.apache.shardingsphere.data.pipeline.core.sqlbuilder.dialect.DialectPipelineSQLBuilder;
  import org.apache.shardingsphere.data.pipeline.core.sqlbuilder.segment.PipelineSQLSegmentBuilder;
  import org.apache.shardingsphere.database.connector.core.spi.DatabaseTypedSPILoader;
  import org.apache.shardingsphere.database.connector.core.type.DatabaseType;
  
  import java.util.Optional;
  
  /**
   * Pipeline prepare SQL builder.
   */
  public final class PipelinePrepareSQLBuilder {
      
      private final DialectPipelineSQLBuilder dialectSQLBuilder;
      
      private final PipelineSQLSegmentBuilder sqlSegmentBuilder;
      
      public PipelinePrepareSQLBuilder(final DatabaseType databaseType) {
          dialectSQLBuilder = DatabaseTypedSPILoader.getService(DialectPipelineSQLBuilder.class, databaseType);
          sqlSegmentBuilder = new PipelineSQLSegmentBuilder(databaseType);
      }
      
      /**
       * Build create schema SQL.
       *
       * @param schemaName schema name
       * @return create schema SQL
       */
      public Optional<String> buildCreateSchemaSQL(final String schemaName) {
          return dialectSQLBuilder.buildCreateSchemaSQL(sqlSegmentBuilder.getEscapedIdentifier(schemaName));
      }
      
      /**
       * Build drop SQL.
       *
       * @param schemaName schema name
       * @param tableName table name
       * @return drop SQL
       */
      public String buildDropSQL(final String schemaName, final String tableName) {
          return String.format("DROP TABLE IF EXISTS %s", sqlSegmentBuilder.getQualifiedTableName(schemaName, tableName));
      }
      
      /**
       * Build count SQL.
       *
       * @param schemaName schema name
       * @param tableName table name
       * @return count SQL
       */
      public String buildCountSQL(final String schemaName, final String tableName) {
          return String.format("SELECT COUNT(*) FROM %s", sqlSegmentBuilder.getQualifiedTableName(schemaName, tableName));
      }
      
      /**
       * Build estimated count SQL.
       *
       * @param catalogName catalog name
       * @param schemaName schema name
       * @param tableName table name
       * @return estimated count SQL
       */
      public Optional<String> buildEstimatedCountSQL(final String catalogName, final String schemaName, final String tableName) {
          return dialectSQLBuilder.buildEstimatedCountSQL(catalogName, sqlSegmentBuilder.getQualifiedTableName(schemaName, tableName));
      }
      
      /**
       * Build unique key minimum maximum values SQL.
       *
       * @param schemaName schema name
       * @param tableName table name
       * @param uniqueKey unique key
       * @return min max unique key SQL
       */
      public String buildUniqueKeyMinMaxValuesSQL(final String schemaName, final String tableName, final String uniqueKey) {
          String escapedUniqueKey = sqlSegmentBuilder.getEscapedIdentifier(uniqueKey);
          return String.format("SELECT MIN(%s), MAX(%s) FROM %s", escapedUniqueKey, escapedUniqueKey, sqlSegmentBuilder.getQualifiedTableName(schemaName, tableName));
      }
      
      /**
       * Build check empty table SQL.
      *
      * @param schemaName schema name
      * @param tableName table name
      * @return check SQL
      */
     public String buildCheckEmptyTableSQL(final String schemaName, final String tableName) {
         return dialectSQLBuilder.buildCheckEmptyTableSQL(sqlSegmentBuilder.getQualifiedTableName(schemaName, tableName));
     }
     
     /**
      * Build split by unique key ranged SQL.
      *
      * @param schemaName schema name
      * @param tableName table name
      * @param uniqueKey unique key
      * @param hasLowerBound has lower bound
      * @return split SQL
      */
     public String buildSplitByUniqueKeyRangedSQL(final String schemaName, final String tableName, final String uniqueKey, final boolean hasLowerBound) {
         String escapedUniqueKey = sqlSegmentBuilder.getEscapedIdentifier(uniqueKey);
         String subQueryClause = dialectSQLBuilder.buildSplitByUniqueKeyRangedSubqueryClause(sqlSegmentBuilder.getQualifiedTableName(schemaName, tableName), escapedUniqueKey, hasLowerBound);
         return String.format("SELECT MAX(%s), COUNT(1), MIN(%s) FROM (%s) t", escapedUniqueKey, escapedUniqueKey, subQueryClause);
     }
 }