using System;

using System.ComponentModel;

using System.Diagnostics;

using System.IO;

using System.Text;

using System.Windows;

using System.Windows.Controls;

using System.Windows.Documents;

using System.Windows.Media;

namespace GitHub.UI

{

public class PromptRichTextBox : RichTextBox, IShortcutContainer

{

public const int BadCommitMessageLength = 51;

public static readonly DependencyProperty PromptTextProperty =

DependencyProperty.Register("PromptText", typeof(string), typeof(PromptRichTextBox), new UIPropertyMetadata(""));

public static readonly DependencyProperty PromptForegroundProperty =

DependencyProperty.Register("PromptForeground", typeof(Brush), typeof(PromptRichTextBox), new UIPropertyMetadata(Brushes.Gray));

public static readonly DependencyProperty TextProperty =

DependencyProperty.Register("Text", typeof(string), typeof(PromptRichTextBox), new FrameworkPropertyMetadata(string.Empty, FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, OnTextPropertyChanged));

public static readonly DependencyProperty IsOverCharacterLimitProperty =

DependencyProperty.Register("IsOverCharacterLimit", typeof(bool), typeof(PromptRichTextBox), new UIPropertyMetadata(false));

public static readonly DependencyProperty CharacterLimitToolTipWarningProperty =

DependencyProperty.Register("CharacterLimitToolTipWarning", typeof(string), typeof(PromptRichTextBox), new UIPropertyMetadata(""));

static readonly Thickness desiredPagePadding = new Thickness(2, 0, 0, 0);

public PromptRichTextBox()

{

Text = "";

TextChanged += OnTextChanged;

DataObject.AddPastingHandler(this, OnPaste);

}

public Brush PromptForeground

{

get { return (Brush)GetValue(PromptForegroundProperty); }

set { SetValue(PromptForegroundProperty, value); }

}

[Localizability(LocalizationCategory.Text)]

[DefaultValue("")]

public string PromptText

{

get { return (string)GetValue(PromptTextProperty); }

set { SetValue(PromptTextProperty, value); }

}

[Localizability(LocalizationCategory.Text)]

[DefaultValue("")]

public string Text

{

get { return (string)GetValue(TextProperty); }

set { SetValue(TextProperty, value ?? ""); }

}

[Localizability(LocalizationCategory.Text)]

[DefaultValue("")]

public string CharacterLimitToolTipWarning

{

get { return (string)GetValue(CharacterLimitToolTipWarningProperty); }

set { SetValue(CharacterLimitToolTipWarningProperty, value); }

}

[DefaultValue(false)]

public bool IsOverCharacterLimit

{

get { return (bool)GetValue(IsOverCharacterLimitProperty); }

set { SetValue(IsOverCharacterLimitProperty, value); }

}

[DefaultValue(true)]

public bool SupportsKeyboardShortcuts { get; set; }

void SetDocumentPadding()

{

if (Document == null) return;

// This is a bug in FlowDocument - you can't set the padding. Well you can, but it doesn't stick.

Document.PagePadding = desiredPagePadding;

}

protected override void OnGotFocus(RoutedEventArgs e)

{

base.OnGotFocus(e);

SetDocumentPadding();

}

protected override void OnGotKeyboardFocus(System.Windows.Input.KeyboardFocusChangedEventArgs e)

{

base.OnGotKeyboardFocus(e);

SetDocumentPadding();

}

// Implementation from StackOverflow: http://stackoverflow.com/a/5049150/598

static void OnPaste(object sender, DataObjectPastingEventArgs e)

{

if (!e.SourceDataObject.GetDataPresent(DataFormats.Rtf, true)) return;

var richTextBox = sender as RichTextBox;

if (richTextBox == null) return;

var rtf = e.SourceDataObject.GetData(DataFormats.Rtf) as string;

var document = new FlowDocument();

var content = SetDocumentContent(document, rtf, DataFormats.Rtf);

if (content.Text == null)

{

throw new GitHubLogicException("WPF ensures this is not null. WPF failed on the job");

}

var d = new DataObject();

var textContent = content.Text;

if (!richTextBox.AcceptsReturn)

{

// Fit the content into one line.

textContent = textContent.Replace(Environment.NewLine, " ");

}

// Take that RTF data and set it as text stripping all the crap. Also, put it on one line.

d.SetData(DataFormats.Text, textContent);

e.DataObject = d;

}

// When the user changes the text in the RichTextBox (via typing in it), data binding will update the

// corresponding property of the view model. Two-way binding will then trigger the OnTextPropertyChanged

// method which will try to update the RichTextBox. That secondary update is unnecessary.

// This little field will help ensure we don't do that unnecessarily.

bool updateDocument = true;

void OnTextChanged(object sender, TextChangedEventArgs e)

{

if (Document == null) return;

updateDocument = false;

TextChanged -= OnTextChanged;

try

{

SetDocumentPadding();

// RichTextBox appends a \r\n at the end.

var documentEndWithoutNewLine = Document.ContentEnd.GetPositionAtOffset(-1 * Environment.NewLine.Length)

?? Document.ContentEnd;

var documentRange = new TextRange(Document.ContentStart, documentEndWithoutNewLine);

if (documentRange.Text.Length > 140)

{

documentEndWithoutNewLine.DeleteTextInRun(140 - documentRange.Text.Length);

documentRange = new TextRange(Document.ContentStart, documentEndWithoutNewLine);

}

documentRange.ClearAllProperties();

IsOverCharacterLimit = false;

Text = documentRange.Text;

var be = GetBindingExpression(TextProperty);

if (be != null)

be.UpdateSource();

if (documentRange.Text.Length <= BadCommitMessageLength) return;

var start = Document.ContentStart.GetPositionAtOffset(BadCommitMessageLength, LogicalDirection.Backward);

var range = new TextRange(start, documentEndWithoutNewLine);

// The next line changes the CaretPosition by 2.

range.ApplyPropertyValue(TextElement.ForegroundProperty, GitHubBrushes.CommitMessageTooLongBrush);

IsOverCharacterLimit = true;

}

finally

{

updateDocument = true;

TextChanged += OnTextChanged;

}

}

static void OnTextPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)

{

var richTextBox = (PromptRichTextBox)d;

if (!richTextBox.updateDocument) return;

var value = e.NewValue as string;

var document = richTextBox.Document;

if (document == null)

{

document = new FlowDocument();

richTextBox.Document = document;

}

try

{

SetDocumentContent(document, value, DataFormats.Text);

}

finally

{

richTextBox.CaretPosition = document.ContentEnd.GetPositionAtOffset(0);

}

}

static TextRange SetDocumentContent(FlowDocument document, string text, string dataFormat)

{

var content = new TextRange(document.ContentStart, document.ContentEnd);

if (content.CanLoad(dataFormat))

{

if (string.IsNullOrEmpty(text))

{

content.Text = text;

}

else

{

using (var stream = new MemoryStream(Encoding.UTF8.GetBytes(text)))

{

content.Load(stream, dataFormat);

}

}

}

return content;

}

}

}