/*
 * Copyright 2013 Guidewire Software, Inc.
 */

package gw.internal.gosu.ir.transform.expression;

import gw.lang.parser.MemberAccessKind;
import gw.internal.gosu.parser.Symbol;
import gw.internal.gosu.parser.BeanAccess;
import gw.internal.gosu.parser.expressions.Identifier;
import gw.internal.gosu.parser.expressions.MemberAccess;
import gw.internal.gosu.parser.expressions.MemberExpansionAccess;
import gw.internal.gosu.ir.transform.ExpressionTransformer;
import gw.internal.gosu.ir.transform.TopLevelTransformationContext;
import gw.lang.ir.IRExpression;
import gw.lang.parser.StandardSymbolTable;
import gw.lang.parser.exceptions.ParseException;
import gw.lang.reflect.IType;
import gw.lang.reflect.IPropertyInfo;
import gw.lang.reflect.java.IJavaType;
import gw.lang.reflect.java.JavaTypes;
import gw.lang.reflect.java.JavaTypes;

/**
 */
public class MemberExpansionAccessTransformer extends AbstractMemberExpansionTransformer<MemberAccess>
{
  public static IRExpression compile( TopLevelTransformationContext cc, MemberExpansionAccess expr )
  {
    MemberExpansionAccessTransformer compiler = new MemberExpansionAccessTransformer( cc, expr );
    return compiler.compile();
  }

  private MemberExpansionAccessTransformer( TopLevelTransformationContext cc, MemberExpansionAccess expr )
  {
    super( cc, expr );
  }

  @Override
  protected IRExpression createIterationExpr(IType rootComponentType, String irIdentifierSym, IType identifierType, IType compType) {
    // Make MemberAccessExpr for *temp_mae_X.<property>

    MemberAccess ma;
    if( rootComponentType.isArray() || JavaTypes.COLLECTION().isAssignableFrom( rootComponentType ) )
    {
      // The MemberExpansionAccess just chains together, so the return type of the nested one is the same as the
      // return type of the outer one
      ma = new MemberExpansionAccess();
      ma.setType( _expr().getType() );
      ma.setMemberAccessKind( MemberAccessKind.EXPANSION ); // expansion implies null-safety on root
    }
    else
    {
      ma = new MemberAccess();
      // We need to set the type of the MemberAccess to exactly the type of the property in question
      ma.setType( getPropertyOrMethodType(rootComponentType, compType) );
      ma.setMemberAccessKind( MemberAccessKind.NULL_SAFE ); // expansion implies null-safety on elements
    }
    Identifier id = new Identifier();
    id.setType( rootComponentType );
    StandardSymbolTable symTable = new StandardSymbolTable();
    Symbol identifierSym = new Symbol( irIdentifierSym, identifierType, symTable);
    id.setSymbol( identifierSym, symTable );
    ma.setRootExpression( id );
    ma.setMemberName( _expr().getMemberName() );

    return ExpressionTransformer.compile( ma, _cc() );
  }

  @Override
  protected IType getPropertyOrMethodType(IType rootComponentType, IType compType) {
    return getProperty( rootComponentType ).getFeatureType();
  }

  private IPropertyInfo getProperty(IType rootComponentType) {
    try {
      return BeanAccess.getPropertyInfoDirectly(rootComponentType, _expr().getMemberName());
    } catch (ParseException e) {
      throw new RuntimeException(e);
    }
  }
}