content: /*
   * 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.asterix.lang.sqlpp.visitor.base;
  
  import java.util.Collection;
  import java.util.List;
  
  import org.apache.asterix.common.exceptions.CompilationException;
  import org.apache.asterix.lang.common.base.ILangExpression;
  import org.apache.asterix.lang.common.clause.GroupbyClause;
  import org.apache.asterix.lang.common.clause.LetClause;
  import org.apache.asterix.lang.common.clause.LimitClause;
  import org.apache.asterix.lang.common.clause.OrderbyClause;
  import org.apache.asterix.lang.common.clause.WhereClause;
  import org.apache.asterix.lang.common.expression.CallExpr;
  import org.apache.asterix.lang.common.expression.FieldAccessor;
  import org.apache.asterix.lang.common.expression.FieldBinding;
  import org.apache.asterix.lang.common.expression.GbyVariableExpressionPair;
  import org.apache.asterix.lang.common.expression.IfExpr;
  import org.apache.asterix.lang.common.expression.IndexAccessor;
  import org.apache.asterix.lang.common.expression.ListConstructor;
  import org.apache.asterix.lang.common.expression.ListSliceExpression;
  import org.apache.asterix.lang.common.expression.LiteralExpr;
  import org.apache.asterix.lang.common.expression.OperatorExpr;
  import org.apache.asterix.lang.common.expression.QuantifiedExpression;
  import org.apache.asterix.lang.common.expression.RecordConstructor;
  import org.apache.asterix.lang.common.expression.UnaryExpr;
  import org.apache.asterix.lang.common.expression.VariableExpr;
  import org.apache.asterix.lang.common.statement.CopyToStatement;
  import org.apache.asterix.lang.common.struct.Identifier;
  import org.apache.asterix.lang.common.struct.QuantifiedPair;
  import org.apache.asterix.lang.sqlpp.clause.AbstractBinaryCorrelateClause;
  import org.apache.asterix.lang.sqlpp.clause.FromClause;
  import org.apache.asterix.lang.sqlpp.clause.FromTerm;
  import org.apache.asterix.lang.sqlpp.clause.HavingClause;
  import org.apache.asterix.lang.sqlpp.clause.JoinClause;
  import org.apache.asterix.lang.sqlpp.clause.NestClause;
  import org.apache.asterix.lang.sqlpp.clause.Projection;
  import org.apache.asterix.lang.sqlpp.clause.SelectBlock;
  import org.apache.asterix.lang.sqlpp.clause.SelectClause;
  import org.apache.asterix.lang.sqlpp.clause.SelectElement;
  import org.apache.asterix.lang.sqlpp.clause.SelectRegular;
  import org.apache.asterix.lang.sqlpp.clause.SelectSetOperation;
  import org.apache.asterix.lang.sqlpp.clause.UnnestClause;
  import org.apache.asterix.lang.sqlpp.expression.CaseExpression;
  import org.apache.asterix.lang.sqlpp.expression.SelectExpression;
  import org.apache.asterix.lang.sqlpp.expression.WindowExpression;
  import org.apache.asterix.lang.sqlpp.struct.SetOperationRight;
  import org.apache.hyracks.algebricks.common.utils.Pair;
  
  /**
   * Base class for visitors that search for expressions having certain properties and return a boolean value
   * indicating whether such expressions were found or not, or {@code null} if search could not be performed.
   */
  public abstract class AbstractSqlppContainsExpressionVisitor<T>
          extends AbstractSqlppQueryExpressionVisitor<Boolean, T> {
  
      @Override
      public Boolean visit(FromClause fromClause, T arg) throws CompilationException {
          for (FromTerm fromTerm : fromClause.getFromTerms()) {
              if (fromTerm.accept(this, arg)) {
                  return true;
              }
          }
          return false;
      }
  
      @Override
      public Boolean visit(FromTerm fromTerm, T arg) throws CompilationException {
          if (visit(fromTerm.getLeftExpression(), arg)) {
              return true;
          }
          if (fromTerm.hasCorrelateClauses()) {
              for (AbstractBinaryCorrelateClause correlateClause : fromTerm.getCorrelateClauses()) {
                  if (correlateClause.accept(this, arg)) {
                      return true;
                  }
              }
          }
          return false;
      }
  
      @Override
      public Boolean visit(JoinClause joinClause, T arg) throws CompilationException {
          return visit(joinClause.getRightExpression(), arg) || visit(joinClause.getConditionExpression(), arg);
      }
  
      @Override
      public Boolean visit(NestClause nestClause, T arg) throws CompilationException {
          return nestClause.accept(this, arg);
      }
  
      @Override
      public Boolean visit(Projection projection, T arg) throws CompilationException {
          return visit(projection.getExpression(), arg);
      }
  
      @Override
      public Boolean visit(SelectBlock selectBlock, T arg) throws CompilationException {
          return (selectBlock.hasFromClause() && visit(selectBlock.getFromClause(), arg))
                  || (selectBlock.hasLetWhereClauses() && visitExprList(selectBlock.getLetWhereList(), arg))
                  || (selectBlock.hasGroupbyClause() && visit(selectBlock.getGroupbyClause(), arg))
                  || (selectBlock.hasLetHavingClausesAfterGroupby()
                          && visitExprList(selectBlock.getLetHavingListAfterGroupby(), arg))
                  || visit(selectBlock.getSelectClause(), arg);
      }
  
      @Override
      public Boolean visit(SelectClause selectClause, T arg) throws CompilationException {
          return (selectClause.selectElement() && visit(selectClause.getSelectElement(), arg))
                  || (selectClause.selectRegular() && visit(selectClause.getSelectRegular(), arg));
      }
  
      @Override
      public Boolean visit(SelectElement selectElement, T arg) throws CompilationException {
          return visit(selectElement.getExpression(), arg);
      }
  
      @Override
      public Boolean visit(SelectRegular selectRegular, T arg) throws CompilationException {
          return visitExprList(selectRegular.getProjections(), arg);
      }
  
      @Override
      public Boolean visit(SelectSetOperation selectSetOperation, T arg) throws CompilationException {
          if (selectSetOperation.getLeftInput().accept(this, arg)) {
              return true;
          }
          if (selectSetOperation.hasRightInputs()) {
              for (SetOperationRight right : selectSetOperation.getRightInputs()) {
                  if (right.getSetOperationRightInput().accept(this, arg)) {
                      return true;
                  }
              }
          }
          return false;
      }
  
      @Override
      public Boolean visit(SelectExpression selectStatement, T arg) throws CompilationException {
          return (selectStatement.hasLetClauses() && visitExprList(selectStatement.getLetList(), arg))
                  || visit(selectStatement.getSelectSetOperation(), arg)
                  || (selectStatement.hasOrderby() && visit(selectStatement.getOrderbyClause(), arg))
                  || (selectStatement.hasLimit() && visit(selectStatement.getLimitClause(), arg));
      }
  
      @Override
      public Boolean visit(UnnestClause unnestClause, T arg) throws CompilationException {
          return visit(unnestClause.getRightExpression(), arg);
      }
  
      @Override
      public Boolean visit(HavingClause havingClause, T arg) throws CompilationException {
          return visit(havingClause.getFilterExpression(), arg);
      }
  
      @Override
      public Boolean visit(CaseExpression caseExpression, T arg) throws CompilationException {
          return visit(caseExpression.getConditionExpr(), arg) || visitExprList(caseExpression.getWhenExprs(), arg)
                  || visitExprList(caseExpression.getThenExprs(), arg) || visit(caseExpression.getElseExpr(), arg);
      }
  
      @Override
      public Boolean visit(LiteralExpr l, T arg) throws CompilationException {
          return false;
      }
  
      @Override
      public Boolean visit(VariableExpr v, T arg) throws CompilationException {
          return false;
      }
  
      @Override
      public Boolean visit(ListConstructor lc, T arg) throws CompilationException {
          return visitExprList(lc.getExprList(), arg);
      }
  
      @Override
      public Boolean visit(RecordConstructor rc, T arg) throws CompilationException {
          for (FieldBinding fb : rc.getFbList()) {
              if (visit(fb.getLeftExpr(), arg)) {
                  return true;
              }
              if (visit(fb.getRightExpr(), arg)) {
                  return true;
              }
          }
          return false;
      }
  
      @Override
      public Boolean visit(OperatorExpr operatorExpr, T arg) throws CompilationException {
          return visitExprList(operatorExpr.getExprList(), arg);
      }
  
      @Override
      public Boolean visit(FieldAccessor fa, T arg) throws CompilationException {
          return visit(fa.getExpr(), arg);
      }
  
      @Override
      public Boolean visit(IndexAccessor ia, T arg) throws CompilationException {
          return visit(ia.getExpr(), arg) || visit(ia.getIndexExpr(), arg);
      }
  
      @Override
      public Boolean visit(ListSliceExpression expression, T arg) throws CompilationException {
          return visit(expression.getExpr(), arg) || visit(expression.getStartIndexExpression(), arg)
                  || visit(expression.getEndIndexExpression(), arg);
      }
  
      @Override
      public Boolean visit(IfExpr ifexpr, T arg) throws CompilationException {
          return visit(ifexpr.getCondExpr(), arg) || visit(ifexpr.getThenExpr(), arg) || visit(ifexpr.getElseExpr(), arg);
      }
  
      @Override
      public Boolean visit(QuantifiedExpression qe, T arg) throws CompilationException {
          for (QuantifiedPair qf : qe.getQuantifiedList()) {
              if (visit(qf.getExpr(), arg)) {
                  return true;
              }
          }
          return visit(qe.getSatisfiesExpr(), arg);
      }
  
      @Override
      public Boolean visit(LetClause lc, T arg) throws CompilationException {
          return visit(lc.getBindingExpr(), arg);
      }
  
      @Override
      public Boolean visit(WhereClause wc, T arg) throws CompilationException {
          return visit(wc.getWhereExpr(), arg);
      }
  
      @Override
      public Boolean visit(OrderbyClause oc, T arg) throws CompilationException {
          return visitExprList(oc.getOrderbyList(), arg);
      }
  
      @Override
      public Boolean visit(GroupbyClause gc, T arg) throws CompilationException {
          for (List<GbyVariableExpressionPair> gbyPairList : gc.getGbyPairList()) {
              for (GbyVariableExpressionPair key : gbyPairList) {
                  if (visit(key.getExpr(), arg)) {
                      return true;
                  }
              }
          }
          if (gc.hasDecorList()) {
              for (GbyVariableExpressionPair key : gc.getDecorPairList()) {
                  if (visit(key.getExpr(), arg)) {
                      return true;
                  }
              }
          }
          if (gc.hasGroupFieldList() && visitFieldList(gc.getGroupFieldList(), arg)) {
              return true;
          }
          if (gc.hasWithMap() && visitExprList(gc.getWithVarMap().keySet(), arg)) {
              return true;
          }
          return false;
      }
  
      @Override
      public Boolean visit(LimitClause lc, T arg) throws CompilationException {
          return visit(lc.getLimitExpr(), arg) || visit(lc.getOffset(), arg);
      }
  
      @Override
      public Boolean visit(UnaryExpr u, T arg) throws CompilationException {
          return visit(u.getExpr(), arg);
      }
  
      @Override
      public Boolean visit(WindowExpression winExpr, T arg) throws CompilationException {
          return (winExpr.hasPartitionList() && visitExprList(winExpr.getPartitionList(), arg))
                  || (winExpr.hasOrderByList() && visitExprList(winExpr.getOrderbyList(), arg))
                  || (winExpr.hasFrameStartExpr() && visit(winExpr.getFrameStartExpr(), arg))
                  || (winExpr.hasFrameEndExpr() && visit(winExpr.getFrameEndExpr(), arg))
                  || (winExpr.hasWindowFieldList() && visitFieldList(winExpr.getWindowFieldList(), arg))
                  || (winExpr.hasAggregateFilterExpr() && visit(winExpr.getAggregateFilterExpr(), arg))
                  || visitExprList(winExpr.getExprList(), arg);
      }
  
      @Override
      public Boolean visit(CallExpr callExpr, T arg) throws CompilationException {
          return visitExprList(callExpr.getExprList(), arg)
                  || (callExpr.hasAggregateFilterExpr() && visit(callExpr.getAggregateFilterExpr(), arg));
      }
  
      @Override
      public Boolean visit(CopyToStatement stmtCopy, T arg) throws CompilationException {
          return stmtCopy.accept(this, arg) || visitExprList(stmtCopy.getPathExpressions(), arg)
                  || visitExprList(stmtCopy.getPartitionExpressions(), arg)
                  || visitExprList(stmtCopy.getOrderByList(), arg);
      }
  
      private boolean visit(ILangExpression expr, T arg) throws CompilationException {
          return expr != null && expr.accept(this, arg);
      }
  
      private <E extends ILangExpression> boolean visitExprList(Collection<E> exprList, T arg)
              throws CompilationException {
          for (E langExpr : exprList) {
              if (visit(langExpr, arg)) {
                  return true;
              }
          }
          return false;
      }
  
      private <E extends ILangExpression> boolean visitFieldList(Collection<Pair<E, Identifier>> fieldList, T arg)
              throws CompilationException {
          for (Pair<E, Identifier> p : fieldList) {
              if (visit(p.first, arg)) {
                  return true;
              }
          }
          return false;
      }
  }
  