// <copyright file="Text.cs" company="Microsoft Corporation">

// Copyright (c) 2008 All Right Reserved

// </copyright>

// <author>Michael S. Scherotter</author>

// <email>mischero@microsoft.com</email>

// <date>2009-01-30</date>

// <summary>Text class for IgnoreWhitespace Custom Attached Property</summary>



namespace Synergist

{

    using System;

    using System.Windows;

    using System.Windows.Controls;

    using System.Windows.Documents;



    /// <summary>

    /// IgnoreWhitespace Custom Attached Property container class

    /// </summary>

    public sealed class Text

    {

        #region Fields

        /// <summary>

        /// IgnoreWhitespace dependency property

        /// </summary>

        public static readonly DependencyProperty IgnoreWhiteSpaceProperty =

            DependencyProperty.RegisterAttached(

            "IgnoreWhiteSpace",

            typeof(bool),

            typeof(Text),

            new PropertyMetadata(false, new PropertyChangedCallback(OnPropertyChanged)));



        #endregion



        #region Constructors

        /// <summary>

        /// Prevents a default instance of the Text class from being created.

        /// </summary>

        private Text()

        {

        }

        #endregion



        #region Methods



        /// <summary>

        /// Get the ignore whitespace property value

        /// </summary>

        /// <param name="source">the dependency object</param>

        /// <returns>whether to ignore the whitespace</returns>

        public static bool GetIgnoreWhiteSpace(DependencyObject source)

        {

            return (bool)source.GetValue(IgnoreWhiteSpaceProperty);

        }



        /// <summary>

        /// Set the ignore whitespace property value

        /// </summary>

        /// <param name="source">a dependency object</param>

        /// <param name="value">whether to ignore the whitespace</param>

        public static void SetIgnoreWhiteSpace(DependencyObject source, bool value)

        {

            source.SetValue(IgnoreWhiteSpaceProperty, value);

        }



        #endregion



        #region Implementation



        /// <summary>

        /// property changed event handler

        /// </summary>

        /// <param name="element">the dependency object (a TextBlock)</param>

        /// <param name="args">the dependency property changed event arguments</param>

        /// <remarks>When the property changes on loading the inline collection is not yet full.  we must wait until the whole element loads.</remarks>

        private static void OnPropertyChanged(DependencyObject element, DependencyPropertyChangedEventArgs args)

        {

            var textBlock = element as TextBlock;



            if (textBlock != null)

            {

                textBlock.Loaded += new RoutedEventHandler(OnTextBlockLoaded);



                UpdateInlines(textBlock.Inlines);

            }

        }



        /// <summary>

        /// Update the inlines when the textbox loads

        /// </summary>

        /// <param name="sender">the textblock</param>

        /// <param name="e">the routed event arguments</param>

        private static void OnTextBlockLoaded(object sender, RoutedEventArgs e)

        {

            var textBlock = sender as TextBlock;



            bool ignoreWhitespace = (bool)textBlock.GetValue(IgnoreWhiteSpaceProperty);



            if (ignoreWhitespace)

            {

                UpdateInlines(textBlock.Inlines);

            }

        }



        /// <summary>

        /// Remove all Run elements with a Text=" "

        /// </summary>

        /// <param name="inlines">an inline collection</param>

        private static void UpdateInlines(InlineCollection inlines)

        {

            bool removed = false;



            do

            {

                removed = false;



                foreach (var inline in inlines)

                {

                    var run = inline as Run;



                    if (run != null)

                    {

                        if (run.Text == " ")

                        {

                            inlines.Remove(run);

                            removed = true;

                            break;

                        }

                    }

                }

            }

            while (removed);

        }



        #endregion

    }

}