Catel - Part 4 of n: Unit testing with Catel

// --------------------------------------------------------------------------------------------------------------------
// <copyright file="MessageService.cs" company="Catel development team">
//   Copyright (c) 2008 - 2011 Catel development team. All rights reserved.
// </copyright>
// <summary>
//   Message service that implements the <see cref="IMessageService" /> by using the <see cref="MessageBox" /> class.
// </summary>
// --------------------------------------------------------------------------------------------------------------------

using System;
using System.Windows;
using Catel.Windows.Properties;

namespace Catel.MVVM.Services
{
	/// <summary>
	/// Message service that implements the <see cref="IMessageService"/> by using the <see cref="MessageBox"/> class.
	/// </summary>
	public class MessageService : ViewModelServiceBase, IMessageService
	{
		#region Methods
		/// <summary>
		/// Translates the message box result.
		/// </summary>
		/// <param name="result">The result.</param>
		/// <returns>
		/// Corresponding <see cref="MessageResult"/>.
		/// </returns>
		private static MessageResult TranslateMessageBoxResult(MessageBoxResult result)
		{
			switch (result)
			{
				case MessageBoxResult.None:
                    return MessageResult.None;

				case MessageBoxResult.OK:
                    return MessageResult.OK;

				case MessageBoxResult.Cancel:
					return MessageResult.Cancel;

				case MessageBoxResult.Yes:
					return MessageResult.Yes;

				case MessageBoxResult.No:
                    return MessageResult.No;

				default:
					throw new ArgumentOutOfRangeException("result");
			}
		}

		/// <summary>
		/// Translates the message image.
		/// </summary>
		/// <param name="image">The image.</param>
		/// <returns>
		/// Corresponding <see cref="MessageBoxImage"/>.
		/// </returns>
		private static MessageBoxImage TranslateMessageImage(MessageImage image)
		{
			switch (image)
			{
				case MessageImage.None:
                    return MessageBoxImage.None;

				case MessageImage.Information:
                    return MessageBoxImage.Information;

				case MessageImage.Question:
					return MessageBoxImage.Question;

				case MessageImage.Exclamation:
					return MessageBoxImage.Exclamation;

				case MessageImage.Error:
                    return MessageBoxImage.Error;

				case MessageImage.Stop:
					return MessageBoxImage.Stop;

				case MessageImage.Warning:
					return MessageBoxImage.Warning;

				default:
					throw new ArgumentOutOfRangeException("image");
			}
		}

		/// <summary>
		/// Translates the message button.
		/// </summary>
		/// <param name="button">The button.</param>
		/// <returns>
		/// Corresponding <see cref="MessageBoxButton"/>.
		/// </returns>
		private static MessageBoxButton TranslateMessageButton(MessageButton button)
		{
			switch (button)
			{
				case MessageButton.OK:
					return MessageBoxButton.OK;

				case MessageButton.OKCancel:
					return MessageBoxButton.OKCancel;

				case MessageButton.YesNo:
					return MessageBoxButton.YesNo;

				case MessageButton.YesNoCancel:
					return MessageBoxButton.YesNoCancel;

				default:
					throw new ArgumentOutOfRangeException("button");
			}
		}
		#endregion

		#region IMessageService Members
        /// <summary>
        /// Shows the error.
        /// </summary>
        /// <param name="exception">The exception.</param>
		public void ShowError(Exception exception)
		{
			ShowError(exception.Message, Resources.ErrorTitle);
		}

		/// <summary>
		/// Shows the error.
		/// </summary>
		/// <param name="message">The message.</param>
		public void ShowError(string message)
		{
			ShowError(message, Resources.ErrorTitle);
		}

		/// <summary>
		/// Shows the error.
		/// </summary>
		/// <param name="message">The message.</param>
		/// <param name="caption">The caption.</param>
		public void ShowError(string message, string caption)
		{
			Show(message, caption, MessageButton.OK, MessageImage.Error);
		}

		/// <summary>
		/// Shows the warning.
		/// </summary>
		/// <param name="message">The message.</param>
		public void ShowWarning(string message)
		{
			ShowWarning(message, Resources.WarningTitle);
		}

		/// <summary>
		/// Shows the warning.
		/// </summary>
		/// <param name="message">The message.</param>
		/// <param name="caption">The caption.</param>
		public void ShowWarning(string message, string caption)
		{
			Show(message, caption, MessageButton.OK, MessageImage.Warning);
		}

		/// <summary>
		/// Shows the information.
		/// </summary>
		/// <param name="message">The message.</param>
		public void ShowInformation(string message)
		{
			ShowInformation(message, Resources.InfoTitle);
		}

		/// <summary>
		/// Shows the information.
		/// </summary>
		/// <param name="message">The message.</param>
		/// <param name="caption">The caption.</param>
		public void ShowInformation(string message, string caption)
		{
			Show(message, caption, MessageButton.OK, MessageImage.Information);
		}

		/// <summary>
		/// Shows the specified message.
		/// </summary>
		/// <param name="message">The message.</param>
		/// <returns>The <see cref="MessageResult"/>.</returns>
		public MessageResult Show(string message)
		{
			return Show(message, Resources.InfoTitle);
		}

		/// <summary>
		/// Shows the specified message.
		/// </summary>
		/// <param name="message">The message.</param>
		/// <param name="caption">The caption.</param>
		/// <returns>The <see cref="MessageResult"/>.</returns>
		public MessageResult Show(string message, string caption)
		{
			return Show(message, caption, MessageButton.OK);
		}

		/// <summary>
		/// Shows the specified message.
		/// </summary>
		/// <param name="message">The message.</param>
		/// <param name="caption">The caption.</param>
		/// <param name="button">The button.</param>
		/// <returns>The <see cref="MessageResult"/>.</returns>
		public MessageResult Show(string message, string caption, MessageButton button)
		{
			return Show(message, caption, button, MessageImage.None);
		}

		/// <summary>
		/// Shows the specified message.
		/// </summary>
		/// <param name="message">The message.</param>
		/// <param name="caption">The caption.</param>
		/// <param name="button">The button.</param>
		/// <param name="icon">The icon to show.</param>
		/// <returns>The <see cref="MessageResult"/>.</returns>
		public MessageResult Show(string message, string caption, MessageButton button, MessageImage icon)
		{
			var messageBoxButton = TranslateMessageButton(button);
			var messageBoxImage = TranslateMessageImage(icon);
			
			var result = MessageBox.Show(message, caption, messageBoxButton, messageBoxImage);

			return TranslateMessageBoxResult(result);
		}
	    #endregion
	}
}