// Copyright (c) 2010 Joe Moorhouse

using ICSharpCode.AvalonEdit;

using ICSharpCode.AvalonEdit.Document;

using ICSharpCode.AvalonEdit.Editing;

using ICSharpCode.AvalonEdit.Highlighting;

using System;

using System.IO;

using System.Reflection;

using System.Runtime.InteropServices;

using System.Windows;

using System.Windows.Input;

namespace PythonConsoleControl

{

/// <summary>

/// Commands that only involve the text editor are outsourced to here.

/// </summary>

internal class PythonEditingCommandHandler

{

private PythonTextEditor textEditor;

private TextArea textArea;

public PythonEditingCommandHandler(PythonTextEditor textEditor)

{

this.textEditor = textEditor;

this.textArea = textEditor.textArea;

}

internal static void CanCutOrCopy(object target, CanExecuteRoutedEventArgs args)

{

// HasSomethingSelected for copy and cut commands

TextArea textArea = GetTextArea(target);

if (textArea != null && textArea.Document != null)

{

args.CanExecute = textArea.Options.CutCopyWholeLine || !textArea.Selection.IsEmpty;

args.Handled = true;

}

}

internal static TextArea GetTextArea(object target)

{

return target as TextArea;

}

internal static void OnCopy(object target, ExecutedRoutedEventArgs args)

{

TextArea textArea = GetTextArea(target);

if (textArea != null && textArea.Document != null)

{

if (textArea.Selection.IsEmpty && textArea.Options.CutCopyWholeLine)

{

DocumentLine currentLine = textArea.Document.GetLineByNumber(textArea.Caret.Line);

CopyWholeLine(textArea, currentLine);

}

else

{

CopySelectedText(textArea);

}

args.Handled = true;

}

}

internal static void OnCut(object target, ExecutedRoutedEventArgs args)

{

TextArea textArea = GetTextArea(target);

if (textArea != null && textArea.Document != null)

{

if (textArea.Selection.IsEmpty && textArea.Options.CutCopyWholeLine)

{

DocumentLine currentLine = textArea.Document.GetLineByNumber(textArea.Caret.Line);

CopyWholeLine(textArea, currentLine);

textArea.Document.Remove(currentLine.Offset, currentLine.TotalLength);

}

else

{

CopySelectedText(textArea);

textArea.Selection.ReplaceSelectionWithText(string.Empty);

}

textArea.Caret.BringCaretToView();

args.Handled = true;

}

}

internal static void CopySelectedText(TextArea textArea)

{

var data = textArea.Selection.CreateDataObject(textArea);

try

{

Clipboard.SetDataObject(data, true);

}

catch (ExternalException)

{

// Apparently this exception sometimes happens randomly.

// The MS controls just ignore it, so we'll do the same.

return;

}

string text = textArea.Selection.GetText();

text = TextUtilities.NormalizeNewLines(text, Environment.NewLine);

//textArea.OnTextCopied(new TextEventArgs(text));

}

internal static void CopyWholeLine(TextArea textArea, DocumentLine line)

{

ISegment wholeLine = new VerySimpleSegment(line.Offset, line.TotalLength);

string text = textArea.Document.GetText(wholeLine);

// Ensure we use the appropriate newline sequence for the OS

text = TextUtilities.NormalizeNewLines(text, Environment.NewLine);

DataObject data = new DataObject(text);

// Also copy text in HTML format to clipboard - good for pasting text into Word

// or to the SharpDevelop forums.

IHighlighter highlighter = textArea.GetService(typeof(IHighlighter)) as IHighlighter;

HtmlClipboard.SetHtml(data, HtmlClipboard.CreateHtmlFragment(textArea.Document, highlighter, wholeLine, new HtmlOptions(textArea.Options)));

MemoryStream lineSelected = new MemoryStream(1);

lineSelected.WriteByte(1);

data.SetData(LineSelectedType, lineSelected, false);

try

{

Clipboard.SetDataObject(data, true);

}

catch (ExternalException)

{

// Apparently this exception sometimes happens randomly.

// The MS controls just ignore it, so we'll do the same.

return;

}

//textArea.OnTextCopied(new TextEventArgs(text));

}

internal static ExecutedRoutedEventHandler OnDelete(RoutedUICommand selectingCommand)

{

return (target, args) =>

{

TextArea textArea = GetTextArea(target);

if (textArea != null && textArea.Document != null)

{

// call BeginUpdate before running the 'selectingCommand'

// so that undoing the delete does not select the deleted character

using (textArea.Document.RunUpdate())

{

Type textAreaType = textArea.GetType();

MethodInfo method;

if (textArea.Selection.IsEmpty)

{

TextViewPosition oldCaretPosition = textArea.Caret.Position;

selectingCommand.Execute(args.Parameter, textArea);

bool hasSomethingDeletable = false;

foreach (ISegment s in textArea.Selection.Segments)

{

method = textAreaType.GetMethod("GetDeletableSegments", BindingFlags.Instance | BindingFlags.NonPublic);

//textArea.GetDeletableSegments(s).Length > 0)

if ((int)method.Invoke(textArea, new Object[] { s }) > 0)

{

hasSomethingDeletable = true;

break;

}

}

if (!hasSomethingDeletable)

{

// If nothing in the selection is deletable; then reset caret+selection

// to the previous value. This prevents the caret from moving through read-only sections.

textArea.Caret.Position = oldCaretPosition;

//textArea.Selection = Selection.Empty;

}

}

method = textAreaType.GetMethod("RemoveSelectedText", BindingFlags.Instance | BindingFlags.NonPublic);

method.Invoke(textArea, new Object[] { });

//textArea.RemoveSelectedText();

}

textArea.Caret.BringCaretToView();

args.Handled = true;

}

};

}

internal static void CanDelete(object target, CanExecuteRoutedEventArgs args)

{

// HasSomethingSelected for delete command

TextArea textArea = GetTextArea(target);

if (textArea != null && textArea.Document != null)

{

args.CanExecute = !textArea.Selection.IsEmpty;

args.Handled = true;

}

}

private const string LineSelectedType = "MSDEVLineSelect"; // This is the type VS 2003 and 2005 use for flagging a whole line copy

private struct VerySimpleSegment : ISegment

{

public readonly int Offset, Length;

int ISegment.Offset

{

get { return Offset; }

}

int ISegment.Length

{

get { return Length; }

}

public int EndOffset

{

get

{

return Offset + Length;

}

}

public VerySimpleSegment(int offset, int length)

{

this.Offset = offset;

this.Length = length;

}

}

}

}