/*
    * 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.sharding.algorithm.sharding.inline;
  
  import groovy.lang.MissingMethodException;
  import org.apache.shardingsphere.infra.algorithm.core.exception.AlgorithmInitializationException;
  import org.apache.shardingsphere.infra.exception.core.ShardingSpherePreconditions;
  import org.apache.shardingsphere.infra.exception.generic.UnsupportedSQLOperationException;
  import org.apache.shardingsphere.infra.expr.core.InlineExpressionParserFactory;
  import org.apache.shardingsphere.sharding.api.sharding.standard.PreciseShardingValue;
  import org.apache.shardingsphere.sharding.api.sharding.standard.RangeShardingValue;
  import org.apache.shardingsphere.sharding.api.sharding.standard.StandardShardingAlgorithm;
  import org.apache.shardingsphere.sharding.exception.algorithm.MismatchedInlineShardingAlgorithmExpressionAndColumnException;
  import org.apache.shardingsphere.sharding.exception.data.NullShardingValueException;
  
  import java.util.Collection;
  import java.util.Collections;
  import java.util.Optional;
  import java.util.Properties;
  
  /**
   * Inline sharding algorithm.
   */
  public final class InlineShardingAlgorithm implements StandardShardingAlgorithm<Comparable<?>> {
      
      private static final String ALGORITHM_EXPRESSION_KEY = "algorithm-expression";
      
      private static final String ALLOW_RANGE_QUERY_KEY = "allow-range-query-with-inline-sharding";
      
      private String algorithmExpression;
      
      private boolean allowRangeQuery;
      
      @Override
      public void init(final Properties props) {
          algorithmExpression = getAlgorithmExpression(props);
          allowRangeQuery = isAllowRangeQuery(props);
      }
      
      private String getAlgorithmExpression(final Properties props) {
          String expression = props.getProperty(ALGORITHM_EXPRESSION_KEY);
          ShardingSpherePreconditions.checkNotEmpty(expression, () -> new AlgorithmInitializationException(this, "Inline sharding algorithm expression cannot be null or empty"));
          return InlineExpressionParserFactory.newInstance(expression.trim()).handlePlaceHolder();
      }
      
      private boolean isAllowRangeQuery(final Properties props) {
          return Boolean.parseBoolean(props.getOrDefault(ALLOW_RANGE_QUERY_KEY, Boolean.FALSE.toString()).toString());
      }
      
      @Override
      public String doSharding(final Collection<String> availableTargetNames, final PreciseShardingValue<Comparable<?>> shardingValue) {
          ShardingSpherePreconditions.checkNotNull(shardingValue.getValue(), NullShardingValueException::new);
          String columnName = shardingValue.getColumnName();
          ShardingSpherePreconditions.checkState(algorithmExpression.contains(columnName), () -> new MismatchedInlineShardingAlgorithmExpressionAndColumnException(algorithmExpression, columnName));
          try {
              return InlineExpressionParserFactory.newInstance(algorithmExpression).evaluateWithArgs(Collections.singletonMap(columnName, shardingValue.getValue()));
          } catch (final MissingMethodException ignored) {
              throw new MismatchedInlineShardingAlgorithmExpressionAndColumnException(algorithmExpression, columnName);
          }
      }
      
      @Override
      public Collection<String> doSharding(final Collection<String> availableTargetNames, final RangeShardingValue<Comparable<?>> shardingValue) {
          ShardingSpherePreconditions.checkState(allowRangeQuery,
                  () -> new UnsupportedSQLOperationException(String.format("Since the property of `%s` is false, inline sharding algorithm can not tackle with range query", ALLOW_RANGE_QUERY_KEY)));
          return availableTargetNames;
      }
      
      @Override
      public Optional<String> getAlgorithmStructure(final String dataNodePrefix, final String shardingColumn) {
          return Optional.of(algorithmExpression.replaceFirst(dataNodePrefix, "").replaceFirst(shardingColumn, "").replaceAll(" ", ""));
      }
      
      @Override
      public String getType() {
          return "INLINE";
      }
  }