// 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.Text;
namespace Unity.CodeEditor.Document
{
internal static class NewLineFinder
{
private static readonly char[] Newline = { '\r', '\n' };
internal static readonly string[] NewlineStrings = { "\r\n", "\r", "\n" };
/// <summary>
/// Gets the location of the next new line character, or SimpleSegment.Invalid
/// if none is found.
/// </summary>
internal static SimpleSegment NextNewLine(string text, int offset)
{
var pos = text.IndexOfAny(Newline, offset);
if (pos >= 0)
{
if (text[pos] == '\r')
{
if (pos + 1 < text.Length && text[pos + 1] == '\n')
return new SimpleSegment(pos, 2);
}
return new SimpleSegment(pos, 1);
}
return SimpleSegment.Invalid;
}
/// <summary>
/// Gets the location of the next new line character, or SimpleSegment.Invalid
/// if none is found.
/// </summary>
internal static SimpleSegment NextNewLine(ITextSource text, int offset)
{
var textLength = text.TextLength;
var pos = text.IndexOfAny(Newline, offset, textLength - offset);
if (pos >= 0)
{
if (text.GetCharAt(pos) == '\r')
{
if (pos + 1 < textLength && text.GetCharAt(pos + 1) == '\n')
return new SimpleSegment(pos, 2);
}
return new SimpleSegment(pos, 1);
}
return SimpleSegment.Invalid;
}
}
partial class TextUtilities
{
/// <summary>
/// Finds the next new line character starting at offset.
/// </summary>
/// <param name="text">The text source to search in.</param>
/// <param name="offset">The starting offset for the search.</param>
/// <param name="newLineType">The string representing the new line that was found, or null if no new line was found.</param>
/// <returns>The position of the first new line starting at or after <paramref name="offset"/>,
/// or -1 if no new line was found.</returns>
internal static int FindNextNewLine(ITextSource text, int offset, out string newLineType)
{
if (text == null)
throw new ArgumentNullException(nameof(text));
if (offset < 0 || offset > text.TextLength)
throw new ArgumentOutOfRangeException(nameof(offset), offset, "offset is outside of text source");
var s = NewLineFinder.NextNewLine(text, offset);
if (s == SimpleSegment.Invalid)
{
newLineType = null;
return -1;
}
if (s.Length == 2)
{
newLineType = "\r\n";
}
else if (text.GetCharAt(s.Offset) == '\n')
{
newLineType = "\n";
}
else
{
newLineType = "\r";
}
return s.Offset;
}
/// <summary>
/// Gets whether the specified string is a newline sequence.
/// </summary>
internal static bool IsNewLine(string newLine)
{
return newLine == "\r\n" || newLine == "\n" || newLine == "\r";
}
/// <summary>
/// Normalizes all new lines in <paramref name="input"/> to be <paramref name="newLine"/>.
/// </summary>
internal static string NormalizeNewLines(string input, string newLine)
{
if (input == null)
return null;
if (!IsNewLine(newLine))
throw new ArgumentException("newLine must be one of the known newline sequences");
var ds = NewLineFinder.NextNewLine(input, 0);
if (ds == SimpleSegment.Invalid) // text does not contain any new lines
return input;
var b = new StringBuilder(input.Length);
var lastEndOffset = 0;
do
{
b.Append(input, lastEndOffset, ds.Offset - lastEndOffset);
b.Append(newLine);
lastEndOffset = ds.EndOffset;
ds = NewLineFinder.NextNewLine(input, lastEndOffset);
} while (ds != SimpleSegment.Invalid);
// remaining string (after last newline)
b.Append(input, lastEndOffset, input.Length - lastEndOffset);
return b.ToString();
}
/// <summary>
/// Gets the newline sequence used in the document at the specified line.
/// </summary>
internal static string GetNewLineFromDocument(IDocument document, int lineNumber)
{
var line = document.GetLineByNumber(lineNumber);
if (line.DelimiterLength == 0)
{
// at the end of the document, there's no line delimiter, so use the delimiter
// from the previous line
line = line.PreviousLine;
if (line == null)
return Environment.NewLine;
}
return document.GetText(line.Offset + line.Length, line.DelimiterLength);
}
}
}