#region Copyright(c) Alexey Sadomov, Vladimir Timashkov. All Rights Reserved.
// -----------------------------------------------------------------------------
// Copyright(c) 2010 Alexey Sadomov, Vladimir Timashkov. All Rights Reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. No Trademark License - Microsoft Public License (Ms-PL) does not grant you rights to use
// authors names, logos, or trademarks.
// 2. If you distribute any portion of the software, you must retain all copyright,
// patent, trademark, and attribution notices that are present in the software.
// 3. If you distribute any portion of the software in source code form, you may do
// so only under this license by including a complete copy of Microsoft Public License (Ms-PL)
// with your distribution. If you distribute any portion of the software in compiled
// or object code form, you may only do so under a license that complies with
// Microsoft Public License (Ms-PL).
// 4. The names of the authors may not be used to endorse or promote products
// derived from this software without specific prior written permission.
//
// The software is licensed "as-is." You bear the risk of using it. The authors
// give no express warranties, guarantees or conditions. You may have additional consumer
// rights under your local laws which this license cannot change. To the extent permitted
// under your local laws, the authors exclude the implied warranties of merchantability,
// fitness for a particular purpose and non-infringement.
// -----------------------------------------------------------------------------
#endregion
using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Reflection;
using System.Text;
using CamlexNET.Impl.Operands;
using CamlexNET.Interfaces;
namespace CamlexNET.Impl.Factories
{
internal class OperandBuilder : IOperandBuilder
{
// ----- Field Ref Operand -----
public IOperand CreateFieldRefOperand(Expression expr, IOperand valueOperand)
{
if (expr is UnaryExpression)
{
expr = ((UnaryExpression)expr).Operand;
}
var methodCallExpression = expr as MethodCallExpression;
var argumentExpression = methodCallExpression.Arguments[0];
if (argumentExpression is ConstantExpression)
{
return this.createFieldRefOperandFromConstantExpression(argumentExpression as ConstantExpression,
valueOperand);
}
return this.createFieldRefOperandFromNonConstantExpression(argumentExpression, valueOperand);
}
private IOperand createFieldRefOperandFromNonConstantExpression(Expression expr, IOperand valueOperand)
{
object value = this.evaluateExpression(expr);
if (value == null || (value.GetType() != typeof(string) && value.GetType() != typeof(Guid)))
{
throw new InvalidValueForFieldRefException(value);
}
if (value.GetType() == typeof(Guid))
{
return this.createFieldRefOperand((Guid)value, valueOperand);
}
return this.createFieldRefOperandByNameOrId((string)value, valueOperand);
}
private IOperand createFieldRefOperandFromConstantExpression(ConstantExpression expr, IOperand valueOperand)
{
var val = expr.Value as string;
return this.createFieldRefOperandByNameOrId(val, valueOperand);
}
private IOperand createFieldRefOperandByNameOrId(string val, IOperand valueOperand)
{
// if string represents guid, then FieldRef with ID should be created
try
{
var guid = new Guid(val);
return this.createFieldRefOperand(guid, valueOperand);
}
catch
{
return this.createFieldRefOperand(val, valueOperand);
}
}
private IOperand createFieldRefOperand(string fieldName, IOperand valueOperand)
{
var attrs = this.getAdditionalAttributesForFieldRefOperands(valueOperand);
return new FieldRefOperand(fieldName, attrs);
}
private List<KeyValuePair<string, string>> getAdditionalAttributesForFieldRefOperands(IOperand valueOperand)
{
if (valueOperand is LookupIdValueOperand)
{
var attrs = new List<KeyValuePair<string, string>>();
attrs.Add(new KeyValuePair<string, string>(Attributes.LookupId, true.ToString()));
return attrs;
}
return new List<KeyValuePair<string, string>>();
}
private IOperand createFieldRefOperand(Guid id, IOperand valueOperand)
{
var attrs = this.getAdditionalAttributesForFieldRefOperands(valueOperand);
return new FieldRefOperand(id, attrs);
}
public IOperand CreateFieldRefOperandWithOrdering(Expression expr, Camlex.OrderDirection orderDirection)
{
var fieldRefOperand = (FieldRefOperand)CreateFieldRefOperand(expr, null);
return new FieldRefOperandWithOrdering(fieldRefOperand, orderDirection);
}
// ----- Value Operand -----
public IOperand CreateValueOperandForNativeSyntax(Expression expr)
{
// determine operand type from expression result (specify null as explicitOperandType)
return CreateValueOperandForNativeSyntax(expr, null);
}
public IOperand CreateValueOperandForNativeSyntax(Expression expr, Type explicitOperandType)
{
return CreateValueOperandForNativeSyntax(expr, explicitOperandType, expr);
}
private IOperand CreateValueOperandForNativeSyntax(Expression expr, Type explicitOperandType, Expression sourceExpr)
{
if (expr is ConstantExpression)
{
return this.createValueOperandFromConstantExpression(expr as ConstantExpression, explicitOperandType, sourceExpr);
}
return this.createValueOperandFromNonConstantExpression(expr, explicitOperandType, sourceExpr);
}
public IOperand CreateValueOperandForStringBasedSyntax(Expression expr)
{
var newExpr = ExpressionHelper.RemoveIncludeTimeValueMethodCallIfAny(expr);
// retrieve internal native expression from string based syntax
var internalExpression = ((UnaryExpression)((UnaryExpression)newExpr).Operand).Operand;
// use conversion type as operand type (subclass of BaseFieldType should be used here)
// because conversion operand has always string type for string based syntax
return this.CreateValueOperandForNativeSyntax(internalExpression, newExpr.Type, expr);
}
private IOperand createValueOperandFromNonConstantExpression(Expression expr, Type explicitOperandType, Expression sourceExpr)
{
object value = this.evaluateExpression(expr);
// if operand type is not specified explicitly try to determine operand type from expression result
var operandType = explicitOperandType;
if (operandType == null)
{
// value can be null
operandType = value != null ? value.GetType() : null;
}
return this.createValueOperand(operandType, value, sourceExpr);
}
private object evaluateExpression(Expression expr)
{
// need to add Expression.Convert(..) in order to define Func<object>
var lambda = Expression.Lambda<Func<object>>(Expression.Convert(expr, typeof(object)));
return lambda.Compile().Invoke();
}
private IOperand createValueOperandFromConstantExpression(ConstantExpression expr, Type explicitOperandType, Expression sourceExpr)
{
// if operand type is not specified explicitly try to determine operand type from expression type
var operandType = explicitOperandType;
if (operandType == null)
{
operandType = expr.Type;
}
return this.createValueOperand(operandType, expr.Value, sourceExpr);
}
private IOperand createValueOperand(Type type, object value, Expression expr)
{
// it is important to have check on NullValueOperand on 1st place
if (value == null)
{
return new NullValueOperand();
}
// string operand can be native or string based
if (type == typeof(string) || type == typeof(DataTypes.Text))
{
return new TextValueOperand((string)value);
}
// integer operand can be native or string based
if (type == typeof(int) || type == typeof(DataTypes.Integer))
{
if (value.GetType() == typeof(int))
{
return new IntegerValueOperand((int) value);
}
if (value.GetType() == typeof(string))
{
return new IntegerValueOperand((string)value);
}
}
// boolean operand can be native or string based
if (type == typeof(bool) || type == typeof(DataTypes.Boolean))
{
if (value.GetType() == typeof(bool))
{
return new BooleanValueOperand((bool)value);
}
if (value.GetType() == typeof(string))
{
return new BooleanValueOperand((string)value);
}
}
// DateTime operand can be native or string based
if (type == typeof(DateTime) || type == typeof(DataTypes.DateTime))
{
var includeTimeValue = ExpressionHelper.IncludeTimeValue(expr);
if (value.GetType() == typeof(DateTime))
{
return new DateTimeValueOperand((DateTime)value, includeTimeValue);
}
if (value.GetType() == typeof(string))
{
return new DateTimeValueOperand((string)value, includeTimeValue);
}
}
// guid operand can be native or string based
if (type == typeof(Guid) || type == typeof(DataTypes.Guid))
{
if (value.GetType() == typeof(Guid))
{
return new GuidValueOperand((Guid)value);
}
if (value.GetType() == typeof(string))
{
return new GuidValueOperand((string)value);
}
}
// for rest of generic types create generic string based operand
if (type.IsSubclassOf(typeof(BaseFieldType)))
{
// there is no LookupId and LookupValue datatypes in CAML. There is only
// Lookup datatype. We introduced different lookup datatypes in order
// to simplify distinguish between lookup values and lookup ids search.
// See http://camlex.codeplex.com/Thread/View.aspx?ThreadId=203560 for details
if (type == typeof(DataTypes.LookupId))
{
return new LookupIdValueOperand((string)value);
}
else if (type == typeof(DataTypes.LookupValue))
{
return new LookupValueValueOperand((string)value);
}
return new GenericStringBasedValueOperand(type, (string) value);
}
throw new NonSupportedOperandTypeException(type);
}
}
}
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