/// <summary> Inserts the given content into this instance. </summary>
/// <param name="caret"> The caret which represents the point at which the content should be
/// inserted. </param>
/// <param name="text"> The text that should be inserted into the text fragment </param>
public TextCaret Insert(TextCaret caret, string text)
{
if (caret.Content != this)
{
throw new ArgumentException("Caret does not refer to this Content instance", nameof(caret));
}
if (text == null)
{
throw new ArgumentNullException(nameof(text));
}
// easy, it's empty
if (text == "")
{
return(caret);
}
var originalNumGraphemes = _buffer.GraphemeLength;
_buffer.InsertText(caret.Offset.CharOffset, text);
var nowNumGraphemes = _buffer.GraphemeLength;
NotifyChanged();
return(TextCaret.FromOffset(this, caret.Offset.GraphemeOffset + nowNumGraphemes - originalNumGraphemes));
}
/// <summary> Retrieves a cursor that points at the given character. </summary>
/// <exception cref="Exception"> Thrown when an exception error condition occurs. </exception>
/// <param name="graphemeIndex"> The index of the grapheme to point at. </param>
/// <returns> A TextBlockValueCursor that is pointing at the given grapheme. </returns>
public TextCaret CursorFromGraphemeIndex(int graphemeIndex)
{
if (graphemeIndex < 0 || graphemeIndex > _buffer.GraphemeLength)
{
throw new ArgumentException($"Invalid index for cursor; index={graphemeIndex}; maximum={_buffer.GraphemeLength}", nameof(graphemeIndex));
}
return(TextCaret.FromOffset(this, graphemeIndex));
}
/// <summary> Inserts the given content into this instance. </summary>
/// <param name="caret"> The caret which represents the point at which the content should be
/// inserted. </param>
/// <param name="newContent"> The content to insert. </param>
/// <param name="autoMerge"> (Optional) True to automatically merge similar fragments together. </param>
public TextCaret Insert(TextCaret caret, TextBlockContent newContent, bool autoMerge = true)
{
if (newContent == this)
{
throw new ArgumentException("Content cannot be inserted into itself", nameof(newContent));
}
return(Insert(caret, newContent.GetText()));
}
/// <summary> Makes sure that <paramref name="caretStart"/> comes before <paramref name="caretEnd"/>. </summary>
private void NormalizePositioning(ref TextCaret caretStart, ref TextCaret caretEnd)
{
if (caretStart.Offset.GraphemeOffset > caretEnd.Offset.GraphemeOffset)
{
var temp = caretStart;
caretStart = caretEnd;
caretEnd = temp;
}
}
private void VerifyExtractParameters(TextCaret caretStart,
TextCaret caretEnd)
{
if (!caretStart.IsValid || caretStart.Content != this)
{
throw new ArgumentException("Start cursor is not pointing at this content", nameof(caretStart));
}
if (!caretEnd.IsValid || caretStart.Content != this)
{
throw new ArgumentException("End cursor is not pointing at this content", nameof(caretEnd));
}
}
public TextBlockContent ExtractOrCloneContent(TextCaret caretStart, TextCaret caretEnd, bool shouldRemoveContent)
{
VerifyExtractParameters(caretStart, caretEnd);
NormalizePositioning(ref caretStart, ref caretEnd);
// zero-width; this check is needed, as the normalization process might shift the end to be
// before the start when both are pointing at the end of a fragment (the start is normalized to
// point at the beginning of the next fragment instead).
if (caretStart == caretEnd)
{
return(new TextBlockContent());
}
var start = caretStart.Offset;
var end = caretEnd.Offset;
if (start == end)
{
return(new TextBlockContent());
}
else if (caretStart.IsAtBlockStart && caretEnd.IsAtBlockEnd)
{
var newContent = new TextBlockContent(this);
if (shouldRemoveContent)
{
RemoveAll();
}
return(newContent);
}
else
{
var clone = new TextBlockContent(_buffer.GetText(start, end));
if (shouldRemoveContent)
{
_buffer.DeleteText(start, end);
NotifyChanged();
}
return(clone);
}
}
/// <summary> Deletes text at the given position. </summary>
public static TextCaret DeleteText(this TextCaret caret, int numberOfGraphemes)
{
var endCaret = caret;
while (numberOfGraphemes > 0)
{
var next = endCaret.GetNextPosition();
if (!next.IsValid)
{
break;
}
endCaret = next;
numberOfGraphemes--;
}
// TODO special case when we're deleting the entire fragment
caret.Content.DeleteText(caret.Offset, endCaret.Offset);
return(TextCaret.FromOffset(caret.Content, caret.Offset.GraphemeOffset));
}
public SerializedData(TextCaret caret)
{
_graphemeOffset = caret.Offset.GraphemeOffset;
_pathToBlock = caret.Block.GetBlockPath();
}
/// <summary> Gets a cursor that is looking at the end of this content. </summary> public TextCaret GetCaretAtEnd() => TextCaret.FromEnd(this);
/// <summary> Gets a cursor that is looking at the beginning of this content. </summary> public TextCaret GetCaretAtStart() => TextCaret.FromBeginning(this);
public TextBlockContent Clone() => CloneContent(TextCaret.FromBeginning(this), TextCaret.FromEnd(this));
public TextBlockContent CloneContent(TextCaret start, TextCaret end) => ExtractOrCloneContent(start, end, shouldRemoveContent: false);
/// <summary> Inserts text at the given location. </summary>
public static TextCaret InsertText(this TextCaret original, string text)
{
return(original.Content.Insert(original, text));
}