Catel - Part 4 of n: Unit testing with Catel

// --------------------------------------------------------------------------------------------------------------------
// <copyright file="ViewModelToModelAttribute.cs" company="Catel development team">
//   Copyright (c) 2008 - 2011 Catel development team. All rights reserved.
// </copyright>
// <summary>
//   Attribute to link a property in a view model to a model.
// </summary>
// --------------------------------------------------------------------------------------------------------------------

using System;

namespace Catel.MVVM
{
	/// <summary>
	/// Attribute to link a property in a view model to a model.
	/// </summary>
	[AttributeUsage(AttributeTargets.Property)]
	public class ViewModelToModelAttribute : Attribute
	{
		#region Constructor & destructor
		/// <summary>
		/// Initializes a new instance of the <see cref="ViewModelToModelAttribute"/> class. This constructor assumes that the name
		/// of the property in the view model is the same as in the model.
		/// </summary>
		/// <param name="model">The property name that holds the model object.</param>
		public ViewModelToModelAttribute(string model)
			: this(model, string.Empty) { }

		/// <summary>
		/// Initializes a new instance of the <see cref="ViewModelToModelAttribute"/> class.
		/// </summary>
		/// <param name="model">The property name that holds the model object.</param>
		/// <param name="property">The property of the model object that should be linked to the <see cref="ViewModelBaseWithoutServices"/> property.</param>
		public ViewModelToModelAttribute(string model, string property)
		{
			Model = model;
			Property = property;
		}
		#endregion

		#region Properties
		/// <summary>
		/// Gets the property name that holds the model object.
        /// <para />
		/// Must be a property on the <see cref="ViewModelBaseWithoutServices"/> implementation, but is allowed to be private.
		/// </summary>
		/// <value>The model property name.</value>
		public string Model { get; internal set; }

		/// <summary>
        /// Gets the property of the model object that should be linked to the <see cref="ViewModelBaseWithoutServices"/> property.
		/// </summary>
		/// <value>The property.</value>
		public string Property { get; internal set; }

		/// <summary>
		/// Gets or sets a value indicating whether to support LLBLGen. When a property on the view model changes, the view model
		/// will try to find the related field ID instead of the related field since LLBLGen does not support nullable related entities.
		/// </summary>
		/// <value><c>true</c> if [support LLBL gen]; otherwise, <c>false</c>.</value>
		public bool SupportLLBLGen { get; set; }

		/// <summary>
		/// Gets or sets the LLBLGen entity property to use when retrieving the value from the view model entity.
        /// <para />
		/// The actual mapping will be like [ViewModel].[ViewModelLLBLGenEntityProperty] = [Model].[ModelLLBLGenEntityProperty].
        /// <para />
        /// If the value is empty, the property to map to is automatically determined by the <see cref="ViewModelBaseWithoutServices"/>.
		/// </summary>
		/// <remarks>
		/// This property is only used when <see cref="SupportLLBLGen"/> is <c>true</c>.
		/// </remarks>
		/// <value>The LLBLGen entity property.</value>
		public string ViewModelLLBLGenEntityProperty { get; set; }

		/// <summary>
		/// Gets or sets the LLBLGen entity property to use when retrieving the value from the view model entity.
        /// <para />
		/// The actual mapping will be like [ViewModel].[ViewModelLLBLGenEntityProperty] = [Model].[ModelLLBLGenEntityProperty].
        /// <para />
        /// If the value is empty, the property to map to is automatically determined by the <see cref="ViewModelBaseWithoutServices"/>.
		/// </summary>
		/// <remarks>
		/// This property is only used when <see cref="SupportLLBLGen"/> is <c>true</c>.
		/// </remarks>
		/// <value>The LLBLGen entity property.</value>
		public string ModelLLBLGenEntityProperty { get; set; }

		/// <summary>
		/// Gets or sets the value to set on the LLBLGen back-end property when the view model property is null.
		/// </summary>
		/// <value>The null value.</value>
		public object NullValue { get; set; }
		#endregion
	}
}