/*
    * 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.binder.context.statement.dml;
  
  import lombok.Getter;
  import org.apache.shardingsphere.infra.binder.context.segment.table.TablesContext;
  import org.apache.shardingsphere.infra.binder.context.statement.CommonSQLStatementContext;
  import org.apache.shardingsphere.infra.binder.context.type.TableAvailable;
  import org.apache.shardingsphere.infra.binder.context.type.WhereAvailable;
  import org.apache.shardingsphere.sql.parser.sql.common.extractor.TableExtractor;
  import org.apache.shardingsphere.sql.parser.sql.common.segment.dml.column.ColumnSegment;
  import org.apache.shardingsphere.sql.parser.sql.common.segment.dml.expr.BinaryOperationExpression;
  import org.apache.shardingsphere.sql.parser.sql.common.segment.dml.predicate.WhereSegment;
  import org.apache.shardingsphere.sql.parser.sql.common.segment.generic.table.SimpleTableSegment;
  import org.apache.shardingsphere.sql.parser.sql.common.statement.dml.UpdateStatement;
  import org.apache.shardingsphere.sql.parser.sql.common.util.ColumnExtractor;
  import org.apache.shardingsphere.sql.parser.sql.common.util.ExpressionExtractUtils;
  
  import java.util.Collection;
  import java.util.LinkedList;
  
  /**
   * Update SQL statement context.
   */
  @Getter
  public final class UpdateStatementContext extends CommonSQLStatementContext implements TableAvailable, WhereAvailable {
      
      private final TablesContext tablesContext;
      
      private final Collection<WhereSegment> whereSegments = new LinkedList<>();
      
      private final Collection<ColumnSegment> columnSegments = new LinkedList<>();
      
      private final Collection<BinaryOperationExpression> joinConditions = new LinkedList<>();
      
      public UpdateStatementContext(final UpdateStatement sqlStatement) {
          super(sqlStatement);
          tablesContext = new TablesContext(getAllSimpleTableSegments(), getDatabaseType());
          getSqlStatement().getWhere().ifPresent(whereSegments::add);
          ColumnExtractor.extractColumnSegments(columnSegments, whereSegments);
          ExpressionExtractUtils.extractJoinConditions(joinConditions, whereSegments);
      }
      
      private Collection<SimpleTableSegment> getAllSimpleTableSegments() {
          TableExtractor tableExtractor = new TableExtractor();
          tableExtractor.extractTablesFromUpdate(getSqlStatement());
          return tableExtractor.getRewriteTables();
      }
      
      @Override
      public UpdateStatement getSqlStatement() {
          return (UpdateStatement) super.getSqlStatement();
      }
      
      @Override
      public Collection<SimpleTableSegment> getAllTables() {
          return tablesContext.getSimpleTableSegments();
      }
      
      @Override
      public Collection<WhereSegment> getWhereSegments() {
          return whereSegments;
      }
      
      @Override
      public Collection<ColumnSegment> getColumnSegments() {
          return columnSegments;
      }
  }