// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
// This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
using System;
using System.Windows;
using System.Windows.Media;
using System.Windows.Media.TextFormatting;
using ICSharpCode.AvalonEdit.Utils;
namespace ICSharpCode.AvalonEdit.Rendering
{
/// <summary>
/// Formatted text (not normal document text).
/// This is used as base class for various VisualLineElements that are displayed using a
/// FormattedText, for example newline markers or collapsed folding sections.
/// </summary>
public class FormattedTextElement : VisualLineElement
{
internal readonly FormattedText formattedText;
internal string text;
internal TextLine textLine;
/// <summary>
/// Creates a new FormattedTextElement that displays the specified text
/// and occupies the specified length in the document.
/// </summary>
public FormattedTextElement(string text, int documentLength) : base(1, documentLength)
{
if (text == null)
throw new ArgumentNullException("text");
this.text = text;
this.BreakBefore = LineBreakCondition.BreakPossible;
this.BreakAfter = LineBreakCondition.BreakPossible;
}
/// <summary>
/// Creates a new FormattedTextElement that displays the specified text
/// and occupies the specified length in the document.
/// </summary>
public FormattedTextElement(TextLine text, int documentLength) : base(1, documentLength)
{
if (text == null)
throw new ArgumentNullException("text");
this.textLine = text;
this.BreakBefore = LineBreakCondition.BreakPossible;
this.BreakAfter = LineBreakCondition.BreakPossible;
}
/// <summary>
/// Creates a new FormattedTextElement that displays the specified text
/// and occupies the specified length in the document.
/// </summary>
public FormattedTextElement(FormattedText text, int documentLength) : base(1, documentLength)
{
if (text == null)
throw new ArgumentNullException("text");
this.formattedText = text;
this.BreakBefore = LineBreakCondition.BreakPossible;
this.BreakAfter = LineBreakCondition.BreakPossible;
}
/// <summary>
/// Gets/sets the line break condition before the element.
/// The default is 'BreakPossible'.
/// </summary>
public LineBreakCondition BreakBefore { get; set; }
/// <summary>
/// Gets/sets the line break condition after the element.
/// The default is 'BreakPossible'.
/// </summary>
public LineBreakCondition BreakAfter { get; set; }
/// <inheritdoc/>
public override TextRun CreateTextRun(int startVisualColumn, ITextRunConstructionContext context)
{
if (textLine == null) {
var formatter = TextFormatterFactory.Create(context.TextView);
textLine = PrepareText(formatter, this.text, this.TextRunProperties);
this.text = null;
}
return new FormattedTextRun(this, this.TextRunProperties);
}
/// <summary>
/// Constructs a TextLine from a simple text.
/// </summary>
public static TextLine PrepareText(TextFormatter formatter, string text, TextRunProperties properties)
{
if (formatter == null)
throw new ArgumentNullException("formatter");
if (text == null)
throw new ArgumentNullException("text");
if (properties == null)
throw new ArgumentNullException("properties");
return formatter.FormatLine(
new SimpleTextSource(text, properties),
0,
32000,
new VisualLineTextParagraphProperties {
defaultTextRunProperties = properties,
textWrapping = TextWrapping.NoWrap,
tabSize = 40
},
null);
}
}
/// <summary>
/// This is the TextRun implementation used by the <see cref="FormattedTextElement"/> class.
/// </summary>
public class FormattedTextRun : TextEmbeddedObject
{
readonly FormattedTextElement element;
TextRunProperties properties;
/// <summary>
/// Creates a new FormattedTextRun.
/// </summary>
public FormattedTextRun(FormattedTextElement element, TextRunProperties properties)
{
if (element == null)
throw new ArgumentNullException("element");
if (properties == null)
throw new ArgumentNullException("properties");
this.properties = properties;
this.element = element;
}
/// <summary>
/// Gets the element for which the FormattedTextRun was created.
/// </summary>
public FormattedTextElement Element {
get { return element; }
}
/// <inheritdoc/>
public override LineBreakCondition BreakBefore {
get { return element.BreakBefore; }
}
/// <inheritdoc/>
public override LineBreakCondition BreakAfter {
get { return element.BreakAfter; }
}
/// <inheritdoc/>
public override bool HasFixedSize {
get { return true; }
}
/// <inheritdoc/>
public override CharacterBufferReference CharacterBufferReference {
get { return new CharacterBufferReference(); }
}
/// <inheritdoc/>
public override int Length {
get { return element.VisualLength; }
}
/// <inheritdoc/>
public override TextRunProperties Properties {
get { return properties; }
}
/// <inheritdoc/>
public override TextEmbeddedObjectMetrics Format(double remainingParagraphWidth)
{
var formattedText = element.formattedText;
if (formattedText != null) {
return new TextEmbeddedObjectMetrics(formattedText.WidthIncludingTrailingWhitespace,
formattedText.Height,
formattedText.Baseline);
} else {
var text = element.textLine;
return new TextEmbeddedObjectMetrics(text.WidthIncludingTrailingWhitespace,
text.Height,
text.Baseline);
}
}
/// <inheritdoc/>
public override Rect ComputeBoundingBox(bool rightToLeft, bool sideways)
{
var formattedText = element.formattedText;
if (formattedText != null) {
return new Rect(0, 0, formattedText.WidthIncludingTrailingWhitespace, formattedText.Height);
} else {
var text = element.textLine;
return new Rect(0, 0, text.WidthIncludingTrailingWhitespace, text.Height);
}
}
/// <inheritdoc/>
public override void Draw(DrawingContext drawingContext, Point origin, bool rightToLeft, bool sideways)
{
if (element.formattedText != null) {
origin.Y -= element.formattedText.Baseline;
drawingContext.DrawText(element.formattedText, origin);
} else {
origin.Y -= element.textLine.Baseline;
element.textLine.Draw(drawingContext, origin, InvertAxes.None);
}
}
}
}