// 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;
namespace ICSharpCode.AvalonEdit.Rendering
{
///
/// Base class for that helps
/// splitting visual elements so that colors (and other text properties) can be easily assigned
/// to individual words/characters.
///
public abstract class ColorizingTransformer : IVisualLineTransformer, ITextViewConnect
{
///
/// Gets the list of elements currently being transformed.
///
protected IList CurrentElements { get; private set; }
///
/// implementation.
/// Sets and calls .
///
public void Transform(ITextRunConstructionContext context, IList elements)
{
if (elements == null)
throw new ArgumentNullException("elements");
if (this.CurrentElements != null)
throw new InvalidOperationException("Recursive Transform() call");
this.CurrentElements = elements;
try {
Colorize(context);
} finally {
this.CurrentElements = null;
}
}
///
/// Performs the colorization.
///
protected abstract void Colorize(ITextRunConstructionContext context);
///
/// Changes visual element properties.
/// This method accesses , so it must be called only during
/// a call.
/// This method splits s as necessary to ensure that the region
/// can be colored by setting the of whole elements,
/// and then calls the on all elements in the region.
///
/// Start visual column of the region to change
/// End visual column of the region to change
/// Action that changes an individual .
protected void ChangeVisualElements(int visualStartColumn, int visualEndColumn, Action action)
{
if (action == null)
throw new ArgumentNullException("action");
for (int i = 0; i < CurrentElements.Count; i++) {
VisualLineElement e = CurrentElements[i];
if (e.VisualColumn > visualEndColumn)
break;
if (e.VisualColumn < visualStartColumn &&
e.VisualColumn + e.VisualLength > visualStartColumn)
{
if (e.CanSplit) {
e.Split(visualStartColumn, CurrentElements, i--);
continue;
}
}
if (e.VisualColumn >= visualStartColumn && e.VisualColumn < visualEndColumn) {
if (e.VisualColumn + e.VisualLength > visualEndColumn) {
if (e.CanSplit) {
e.Split(visualEndColumn, CurrentElements, i--);
continue;
}
} else {
action(e);
}
}
}
}
///
/// Called when added to a text view.
///
protected virtual void OnAddToTextView(TextView textView)
{
}
///
/// Called when removed from a text view.
///
protected virtual void OnRemoveFromTextView(TextView textView)
{
}
void ITextViewConnect.AddToTextView(TextView textView)
{
OnAddToTextView(textView);
}
void ITextViewConnect.RemoveFromTextView(TextView textView)
{
OnRemoveFromTextView(textView);
}
}
}