text: /*
   ***************************************************************************************
   *  Copyright (C) 2006 EsperTech, Inc. All rights reserved.                            *
   *  http://www.espertech.com/esper                                                     *
   *  http://www.espertech.com                                                           *
   *  ---------------------------------------------------------------------------------- *
   *  The software in this package is published under the terms of the GPL license       *
   *  a copy of which has been included with this distribution in the license.txt file.  *
   ***************************************************************************************
   */
  package com.espertech.esper.common.internal.epl.datetime.interval;
  
  import com.espertech.esper.common.client.EventBean;
  import com.espertech.esper.common.client.type.EPTypeClass;
  import com.espertech.esper.common.internal.bytecodemodel.base.CodegenClassScope;
  import com.espertech.esper.common.internal.bytecodemodel.base.CodegenMethod;
  import com.espertech.esper.common.internal.bytecodemodel.base.CodegenMethodScope;
  import com.espertech.esper.common.internal.bytecodemodel.model.expression.CodegenExpression;
  import com.espertech.esper.common.internal.bytecodemodel.model.expression.CodegenExpressionRef;
  import com.espertech.esper.common.internal.epl.expression.codegen.CodegenLegoCast;
  import com.espertech.esper.common.internal.epl.expression.codegen.ExprForgeCodegenSymbol;
  import com.espertech.esper.common.internal.epl.expression.core.*;
  import com.espertech.esper.common.internal.event.core.EventPropertyGetterSPI;
  
  import java.io.StringWriter;
  
  import static com.espertech.esper.common.internal.bytecodemodel.model.expression.CodegenExpressionBuilder.*;
  
  public class ExprEvaluatorStreamDTProp implements ExprForge, ExprEvaluator, ExprNodeRenderable {
  
      private final int streamId;
      private final EventPropertyGetterSPI getter;
      private final EPTypeClass getterReturnTypeBoxed;
  
      public ExprEvaluatorStreamDTProp(int streamId, EventPropertyGetterSPI getter, EPTypeClass getterReturnTypeBoxed) {
          this.streamId = streamId;
          this.getter = getter;
          this.getterReturnTypeBoxed = getterReturnTypeBoxed;
      }
  
      public Object evaluate(EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext context) {
          EventBean event = eventsPerStream[streamId];
          if (event == null) {
              return null;
          }
          return getter.get(event);
      }
  
      public ExprForgeConstantType getForgeConstantType() {
          return ExprForgeConstantType.NONCONST;
      }
  
      public ExprEvaluator getExprEvaluator() {
          return this;
      }
  
      public CodegenExpression evaluateCodegen(EPTypeClass requiredType, CodegenMethodScope codegenMethodScope, ExprForgeCodegenSymbol exprSymbol, CodegenClassScope codegenClassScope) {
          CodegenMethod methodNode = codegenMethodScope.makeChild(getterReturnTypeBoxed, ExprEvaluatorStreamDTProp.class, codegenClassScope);
  
          CodegenExpressionRef refEPS = exprSymbol.getAddEPS(methodNode);
  
          methodNode.getBlock()
                  .declareVar(EventBean.EPTYPE, "event", arrayAtIndex(refEPS, constant(streamId)))
                  .ifRefNullReturnNull("event")
                  .methodReturn(CodegenLegoCast.castSafeFromObjectType(getterReturnTypeBoxed, getter.eventBeanGetCodegen(ref("event"), methodNode, codegenClassScope)));
          return localMethod(methodNode);
      }
  
      public EPTypeClass getEvaluationType() {
          return getterReturnTypeBoxed;
      }
  
      public ExprNodeRenderable getForgeRenderable() {
          return this;
      }
  
      public void toEPL(StringWriter writer, ExprPrecedenceEnum parentPrecedence, ExprNodeRenderableFlags flags) {
          writer.append(this.getClass().getSimpleName());
      }
  }
  