// Copyright (c) 2014 AlphaSierraPapa for the SharpDevelop Team
//
// Permission is hereby granted, free of charge, to any person obtaining a copy of this
// software and associated documentation files (the "Software"), to deal in the Software
// without restriction, including without limitation the rights to use, copy, modify, merge,
// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
// to whom the Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all copies or
// substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Unity.CodeEditor.Document;
using Unity.CodeEditor.Utils;
namespace Unity.CodeEditor.Editing
{
/// <summary>
/// Base class for selections.
/// </summary>
internal abstract class Selection
{
/// <summary>
/// Creates a new simple selection that selects the text from startOffset to endOffset.
/// </summary>
internal static Selection Create(TextArea textArea, int startOffset, int endOffset)
{
if (textArea == null)
throw new ArgumentNullException(nameof(textArea));
if (startOffset == endOffset)
return textArea.EmptySelection;
return new SimpleSelection(textArea,
new TextViewPosition(textArea.Document.GetLocation(startOffset)),
new TextViewPosition(textArea.Document.GetLocation(endOffset)));
}
internal static Selection Create(TextArea textArea, TextViewPosition start, TextViewPosition end)
{
if (textArea == null)
throw new ArgumentNullException(nameof(textArea));
if (textArea.Document.GetOffset(start.Location) == textArea.Document.GetOffset(end.Location) && start.VisualColumn == end.VisualColumn)
return textArea.EmptySelection;
return new SimpleSelection(textArea, start, end);
}
/// <summary>
/// Creates a new simple selection that selects the text in the specified segment.
/// </summary>
internal static Selection Create(TextArea textArea, ISegment segment)
{
if (segment == null)
throw new ArgumentNullException(nameof(segment));
return Create(textArea, segment.Offset, segment.EndOffset);
}
internal TextArea TextArea { get; }
/// <summary>
/// Constructor for Selection.
/// </summary>
protected Selection(TextArea textArea)
{
TextArea = textArea ?? throw new ArgumentNullException(nameof(textArea));
}
/// <summary>
/// Gets the start position of the selection.
/// </summary>
internal abstract TextViewPosition StartPosition { get; }
/// <summary>
/// Gets the end position of the selection.
/// </summary>
internal abstract TextViewPosition EndPosition { get; }
/// <summary>
/// Gets the selected text segments.
/// </summary>
internal abstract IEnumerable<SelectionSegment> Segments { get; }
/// <summary>
/// Gets the smallest segment that contains all segments in this selection.
/// May return null if the selection is empty.
/// </summary>
internal abstract ISegment SurroundingSegment { get; }
/// <summary>
/// Replaces the selection with the specified text.
/// </summary>
internal abstract void ReplaceSelectionWithText(string newText);
internal string AddSpacesIfRequired(string newText, TextViewPosition start, TextViewPosition end)
{
if (EnableVirtualSpace && InsertVirtualSpaces(newText, start, end))
{
var line = TextArea.Document.GetLineByNumber(start.Line);
var lineText = TextArea.Document.GetText(line);
var vLine = TextArea.TextView.GetOrConstructVisualLine(line);
var colDiff = start.VisualColumn - vLine.VisualLengthWithEndOfLineMarker;
if (colDiff > 0)
{
var additionalSpaces = "";
if (!TextArea.Options.ConvertTabsToSpaces && lineText.Trim('\t').Length == 0)
{
var tabCount = colDiff / TextArea.Options.IndentationSize;
additionalSpaces = new string('\t', tabCount);
colDiff -= tabCount * TextArea.Options.IndentationSize;
}
additionalSpaces += new string(' ', colDiff);
return additionalSpaces + newText;
}
}
return newText;
}
private bool InsertVirtualSpaces(string newText, TextViewPosition start, TextViewPosition end)
{
return (!string.IsNullOrEmpty(newText) || !(IsInVirtualSpace(start) && IsInVirtualSpace(end)))
&& newText != "\r\n"
&& newText != "\n"
&& newText != "\r";
}
private bool IsInVirtualSpace(TextViewPosition pos)
{
return pos.VisualColumn > TextArea.TextView.GetOrConstructVisualLine(TextArea.Document.GetLineByNumber(pos.Line)).VisualLength;
}
/// <summary>
/// Updates the selection when the document changes.
/// </summary>
internal abstract Selection UpdateOnDocumentChange(DocumentChangeEventArgs e);
/// <summary>
/// Gets whether the selection is empty.
/// </summary>
internal virtual bool IsEmpty => Length == 0;
/// <summary>
/// Gets whether virtual space is enabled for this selection.
/// </summary>
internal virtual bool EnableVirtualSpace => TextArea.Options.EnableVirtualSpace;
/// <summary>
/// Gets the selection length.
/// </summary>
internal abstract int Length { get; }
/// <summary>
/// Returns a new selection with the changed end point.
/// </summary>
/// <exception cref="NotSupportedException">Cannot set endpoint for empty selection</exception>
internal abstract Selection SetEndpoint(TextViewPosition endPosition);
/// <summary>
/// If this selection is empty, starts a new selection from <paramref name="startPosition"/> to
/// <paramref name="endPosition"/>, otherwise, changes the endpoint of this selection.
/// </summary>
internal abstract Selection StartSelectionOrSetEndpoint(TextViewPosition startPosition, TextViewPosition endPosition);
/// <summary>
/// Gets whether the selection is multi-line.
/// </summary>
internal virtual bool IsMultiline
{
get
{
var surroundingSegment = SurroundingSegment;
if (surroundingSegment == null)
return false;
var start = surroundingSegment.Offset;
var end = start + surroundingSegment.Length;
var document = TextArea.Document;
if (document == null)
throw ThrowUtil.NoDocumentAssigned();
return document.GetLineByOffset(start) != document.GetLineByOffset(end);
}
}
/// <summary>
/// Gets the selected text.
/// </summary>
internal virtual string GetText()
{
var document = TextArea.Document;
if (document == null)
throw ThrowUtil.NoDocumentAssigned();
StringBuilder b = null;
string text = null;
foreach (var s in Segments)
{
if (text != null)
{
if (b == null)
b = new StringBuilder(text);
else
b.Append(text);
}
text = document.GetText(s);
}
if (b != null)
{
if (text != null) b.Append(text);
return b.ToString();
}
else
{
return text ?? string.Empty;
}
}
// TODO: html
/// <summary>
/// Creates a HTML fragment for the selected text.
/// </summary>
//public string CreateHtmlFragment(HtmlOptions options)
//{
// if (options == null)
// throw new ArgumentNullException("options");
// IHighlighter highlighter = textArea.GetService(typeof(IHighlighter)) as IHighlighter;
// StringBuilder html = new StringBuilder();
// bool first = true;
// foreach (ISegment selectedSegment in this.Segments) {
// if (first)
// first = false;
// else
// html.AppendLine("<br>");
// html.Append(HtmlClipboard.CreateHtmlFragment(textArea.Document, highlighter, selectedSegment, options));
// }
// return html.ToString();
//}
/// <inheritdoc/>
public abstract override bool Equals(object obj);
/// <inheritdoc/>
public abstract override int GetHashCode();
/// <summary>
/// Gets whether the specified offset is included in the selection.
/// </summary>
/// <returns>True, if the selection contains the offset (selection borders inclusive);
/// otherwise, false.</returns>
internal virtual bool Contains(int offset)
{
if (IsEmpty)
{
return false;
}
return SurroundingSegment.Contains(offset, 0) &&
Segments.Any(s => s.Contains(offset, 0));
}
// TODO: clipboard
///// <summary>
///// Creates a data object containing the selection's text.
///// </summary>
//public virtual DataObject CreateDataObject(TextArea textArea)
//{
// DataObject data = new DataObject();
// // Ensure we use the appropriate newline sequence for the OS
// string text = TextUtilities.NormalizeNewLines(GetText(), Environment.NewLine);
// // Enable drag/drop to Word, Notepad++ and others
// if (EditingCommandHandler.ConfirmDataFormat(textArea, data, DataFormats.UnicodeText)) {
// data.SetText(text);
// }
// // Enable drag/drop to SciTe:
// // We cannot use SetText, thus we need to use typeof(string).FullName as data format.
// // new DataObject(object) calls SetData(object), which in turn calls SetData(Type, data),
// // which then uses Type.FullName as format.
// // We immitate that behavior here as well:
// if (EditingCommandHandler.ConfirmDataFormat(textArea, data, typeof(string).FullName)) {
// data.SetData(typeof(string).FullName, text);
// }
// // Also copy text in HTML format to clipboard - good for pasting text into Word
// // or to the SharpDevelop forums.
// if (EditingCommandHandler.ConfirmDataFormat(textArea, data, DataFormats.Html)) {
// HtmlClipboard.SetHtml(data, CreateHtmlFragment(new HtmlOptions(textArea.Options)));
// }
// return data;
//}
}
}