Remove old duplicate methods in CalciteLogicalIndexScan

Signed-off-by: Songkan Tang <songkant@amazon.com>

Author: songkant-aws

opensearch/src/main/java/org/opensearch/sql/opensearch/storage/scan/CalciteLogicalIndexScan.java

@@ -5,15 +5,10 @@
 
 package org.opensearch.sql.opensearch.storage.scan;
 
-import static org.opensearch.sql.opensearch.storage.serde.ScriptParameterHelper.MISSING_MAX;
-
 import com.google.common.collect.ImmutableList;
-import java.util.ArrayList;
-import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
-import java.util.function.Supplier;
 import java.util.stream.Collectors;
 import lombok.Getter;
 import org.apache.calcite.plan.Convention;
@@ -26,7 +21,6 @@
 import org.apache.calcite.rel.RelCollation;
 import org.apache.calcite.rel.RelCollations;
 import org.apache.calcite.rel.RelFieldCollation;
-import org.apache.calcite.rel.RelFieldCollation.Direction;
 import org.apache.calcite.rel.core.Aggregate;
 import org.apache.calcite.rel.core.Filter;
 import org.apache.calcite.rel.core.Project;
@@ -37,19 +31,13 @@
 import org.apache.calcite.rel.type.RelDataTypeFactory;
 import org.apache.calcite.rel.type.RelDataTypeField;
 import org.apache.calcite.rex.RexBuilder;
-import org.apache.calcite.rex.RexCall;
 import org.apache.calcite.rex.RexNode;
 import org.apache.calcite.sql.fun.SqlStdOperatorTable;
-import org.apache.calcite.sql.type.SqlTypeName;
 import org.apache.commons.lang3.tuple.Pair;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.opensearch.search.aggregations.AggregationBuilder;
 import org.opensearch.search.aggregations.bucket.composite.CompositeAggregationBuilder;
-import org.opensearch.search.sort.ScriptSortBuilder.ScriptSortType;
-import org.opensearch.search.sort.SortBuilder;
-import org.opensearch.search.sort.SortBuilders;
-import org.opensearch.search.sort.SortOrder;
 import org.opensearch.sql.ast.expression.Argument;
 import org.opensearch.sql.calcite.utils.OpenSearchTypeFactory;
 import org.opensearch.sql.common.setting.Settings;
@@ -60,7 +48,6 @@
 import org.opensearch.sql.opensearch.planner.rules.EnumerableIndexScanRule;
 import org.opensearch.sql.opensearch.planner.rules.OpenSearchIndexRules;
 import org.opensearch.sql.opensearch.request.AggregateAnalyzer;
-import org.opensearch.sql.opensearch.request.OpenSearchRequestBuilder.PushDownUnSupportedException;
 import org.opensearch.sql.opensearch.request.PredicateAnalyzer;
 import org.opensearch.sql.opensearch.request.PredicateAnalyzer.QueryExpression;
 import org.opensearch.sql.opensearch.response.agg.OpenSearchAggregationResponseParser;
@@ -74,7 +61,6 @@
 import org.opensearch.sql.opensearch.storage.scan.context.PushDownContext;
 import org.opensearch.sql.opensearch.storage.scan.context.PushDownType;
 import org.opensearch.sql.opensearch.storage.scan.context.RareTopDigest;
-import org.opensearch.sql.opensearch.storage.scan.context.SortExprDigest;
 
 /** The logical relational operator representing a scan of an OpenSearchIndex type. */
 @Getter
@@ -440,98 +426,4 @@ public AbstractRelNode pushDownLimit(LogicalSort sort, Integer limit, Integer of
     }
     return null;
   }
-
-  /**
-   * Push down sort expressions to OpenSearch level. Supports mixed RexCall and field sort
-   * expressions.
-   *
-   * @param sortExprDigests List of SortExprDigest with expressions and collation information
-   * @return CalciteLogicalIndexScan with sort expressions pushed down, or null if pushdown fails
-   */
-  public CalciteLogicalIndexScan pushdownSortExpr(List<SortExprDigest> sortExprDigests) {
-    try {
-      if (sortExprDigests == null || sortExprDigests.isEmpty()) {
-        return null;
-      }
-
-      CalciteLogicalIndexScan newScan =
-          new CalciteLogicalIndexScan(
-              getCluster(),
-              traitSet,
-              hints,
-              table,
-              osIndex,
-              getRowType(),
-              pushDownContext.cloneWithoutSort());
-
-      List<Supplier<SortBuilder<?>>> sortBuilderSuppliers = new ArrayList<>();
-      for (SortExprDigest digest : sortExprDigests) {
-        SortOrder order =
-            Direction.DESCENDING.equals(digest.getDirection()) ? SortOrder.DESC : SortOrder.ASC;
-
-        if (digest.isSimpleFieldReference()) {
-          String missing =
-              switch (digest.getNullDirection()) {
-                case FIRST -> "_first";
-                case LAST -> "_last";
-                default -> null;
-              };
-          sortBuilderSuppliers.add(
-              () -> SortBuilders.fieldSort(digest.getFieldName()).order(order).missing(missing));
-          continue;
-        }
-        RexNode sortExpr = digest.getExpression();
-        assert sortExpr instanceof RexCall : "sort expression should be RexCall";
-        Map<String, Object> missingValueParams =
-            new LinkedHashMap<>() {
-              {
-                put(MISSING_MAX, digest.isMissingMax());
-              }
-            };
-        // Complex expression - use ScriptQueryExpression to generate script for sort
-        PredicateAnalyzer.ScriptQueryExpression scriptExpr =
-            new PredicateAnalyzer.ScriptQueryExpression(
-                digest.getExpression(),
-                rowType,
-                osIndex.getAllFieldTypes(),
-                getCluster(),
-                missingValueParams);
-        // Determine the correct ScriptSortType based on the expression's return type
-        ScriptSortType sortType = getScriptSortType(sortExpr.getType());
-
-        sortBuilderSuppliers.add(
-            () -> SortBuilders.scriptSort(scriptExpr.getScript(), sortType).order(order));
-      }
-
-      // Create action to push down sort expressions to OpenSearch
-      OSRequestBuilderAction action =
-          requestBuilder -> requestBuilder.pushDownSortSuppliers(sortBuilderSuppliers);
-
-      newScan.pushDownContext.add(PushDownType.SORT_EXPR, sortExprDigests, action);
-      return newScan;
-    } catch (Exception e) {
-      if (LOG.isDebugEnabled()) {
-        LOG.debug("Cannot pushdown sort expressions: {}", sortExprDigests, e);
-      }
-    }
-    return null;
-  }
-
-  /**
-   * Determine the appropriate ScriptSortType based on the expression's return type.
-   *
-   * @param relDataType the return type of the expression
-   * @return the appropriate ScriptSortType
-   */
-  private ScriptSortType getScriptSortType(RelDataType relDataType) {
-    if (SqlTypeName.CHAR_TYPES.contains(relDataType.getSqlTypeName())) {
-      return ScriptSortType.STRING;
-    } else if (SqlTypeName.INT_TYPES.contains(relDataType.getSqlTypeName())
-        || SqlTypeName.APPROX_TYPES.contains(relDataType.getSqlTypeName())) {
-      return ScriptSortType.NUMBER;
-    } else {
-      throw new PushDownUnSupportedException(
-          "Unsupported type for sort expression pushdown: " + relDataType);
-    }
-  }
 }