// 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.Diagnostics.CodeAnalysis;
using System.IO;
namespace Unity.CodeEditor.Document
{
/// <summary>
/// A read-only view on a (potentially mutable) text source.
/// The IDocument interface derives from this interface.
/// </summary>
internal interface ITextSource
{
/// <summary>
/// Gets a version identifier for this text source.
/// Returns null for unversioned text sources.
/// </summary>
ITextSourceVersion Version { get; }
/// <summary>
/// Creates an immutable snapshot of this text source.
/// Unlike all other methods in this interface, this method is thread-safe.
/// </summary>
ITextSource CreateSnapshot();
/// <summary>
/// Creates an immutable snapshot of a part of this text source.
/// Unlike all other methods in this interface, this method is thread-safe.
/// </summary>
ITextSource CreateSnapshot(int offset, int length);
/// <summary>
/// Creates a new TextReader to read from this text source.
/// </summary>
TextReader CreateReader();
/// <summary>
/// Creates a new TextReader to read from this text source.
/// </summary>
TextReader CreateReader(int offset, int length);
/// <summary>
/// Gets the total text length.
/// </summary>
/// <returns>The length of the text, in characters.</returns>
/// <remarks>This is the same as Text.Length, but is more efficient because
/// it doesn't require creating a String object.</remarks>
int TextLength { get; }
/// <summary>
/// Gets the whole text as string.
/// </summary>
[SuppressMessage("Microsoft.Naming", "CA1721:PropertyNamesShouldNotMatchGetMethods")]
string Text { get; }
/// <summary>
/// Gets a character at the specified position in the document.
/// </summary>
/// <paramref name="offset">The index of the character to get.</paramref>
/// <exception cref="ArgumentOutOfRangeException">Offset is outside the valid range (0 to TextLength-1).</exception>
/// <returns>The character at the specified position.</returns>
/// <remarks>This is the same as Text[offset], but is more efficient because
/// it doesn't require creating a String object.</remarks>
char GetCharAt(int offset);
/// <summary>
/// Retrieves the text for a portion of the document.
/// </summary>
/// <exception cref="ArgumentOutOfRangeException">offset or length is outside the valid range.</exception>
/// <remarks>This is the same as Text.Substring, but is more efficient because
/// it doesn't require creating a String object for the whole document.</remarks>
string GetText(int offset, int length);
/// <summary>
/// Retrieves the text for a portion of the document as ReadOnlyMemory<char>.
/// </summary>
/// <exception cref="ArgumentOutOfRangeException">offset or length is outside the valid range.</exception>
/// <remarks>This method may be more efficient than GetText(int, int) because it can avoid allocating a new string
/// in some implementations.</remarks>
ReadOnlyMemory<char> GetTextAsMemory(int offset, int length);
/// <summary>
/// Retrieves the text for a portion of the document.
/// </summary>
/// <exception cref="ArgumentOutOfRangeException">offset or length is outside the valid range.</exception>
string GetText(ISegment segment);
/// <summary>
/// Writes the text from this document into the TextWriter.
/// </summary>
void WriteTextTo(TextWriter writer);
/// <summary>
/// Writes the text from this document into the TextWriter.
/// </summary>
void WriteTextTo(TextWriter writer, int offset, int length);
/// <summary>
/// Gets the index of the first occurrence of the character in the specified array.
/// </summary>
/// <param name="c">Character to search for</param>
/// <param name="startIndex">Start index of the area to search.</param>
/// <param name="count">Length of the area to search.</param>
/// <returns>The first index where the character was found; or -1 if no occurrence was found.</returns>
int IndexOf(char c, int startIndex, int count);
/// <summary>
/// Gets the index of the first occurrence of any character in the specified array.
/// </summary>
/// <param name="anyOf">Characters to search for</param>
/// <param name="startIndex">Start index of the area to search.</param>
/// <param name="count">Length of the area to search.</param>
/// <returns>The first index where any character was found; or -1 if no occurrence was found.</returns>
int IndexOfAny(char[] anyOf, int startIndex, int count);
/// <summary>
/// Gets the index of the first occurrence of the specified search text in this text source.
/// </summary>
/// <param name="searchText">The search text</param>
/// <param name="startIndex">Start index of the area to search.</param>
/// <param name="count">Length of the area to search.</param>
/// <param name="comparisonType">String comparison to use.</param>
/// <returns>The first index where the search term was found; or -1 if no occurrence was found.</returns>
int IndexOf(string searchText, int startIndex, int count, StringComparison comparisonType);
/// <summary>
/// Gets the index of the last occurrence of the specified character in this text source.
/// </summary>
/// <param name="c">The search character</param>
/// <param name="startIndex">Start index of the area to search.</param>
/// <param name="count">Length of the area to search.</param>
/// <returns>The last index where the search term was found; or -1 if no occurrence was found.</returns>
/// <remarks>The search proceeds backwards from (startIndex+count) to startIndex.
/// This is different than the meaning of the parameters on string.LastIndexOf!</remarks>
int LastIndexOf(char c, int startIndex, int count);
/// <summary>
/// Gets the index of the last occurrence of the specified search text in this text source.
/// </summary>
/// <param name="searchText">The search text</param>
/// <param name="startIndex">Start index of the area to search.</param>
/// <param name="count">Length of the area to search.</param>
/// <param name="comparisonType">String comparison to use.</param>
/// <returns>The last index where the search term was found; or -1 if no occurrence was found.</returns>
/// <remarks>The search proceeds backwards from (startIndex+count) to startIndex.
/// This is different than the meaning of the parameters on string.LastIndexOf!</remarks>
int LastIndexOf(string searchText, int startIndex, int count, StringComparison comparisonType);
/* What about:
void Insert (int offset, string value);
void Remove (int offset, int count);
void Remove (ISegment segment);
void Replace (int offset, int count, string value);
Or more search operations:
IEnumerable<int> SearchForward (string pattern, int startIndex);
IEnumerable<int> SearchForwardIgnoreCase (string pattern, int startIndex);
IEnumerable<int> SearchBackward (string pattern, int startIndex);
IEnumerable<int> SearchBackwardIgnoreCase (string pattern, int startIndex);
*/
}
/// <summary>
/// Represents a version identifier for a text source.
/// </summary>
/// <remarks>
/// Verions can be used to efficiently detect whether a document has changed and needs reparsing;
/// or even to implement incremental parsers.
/// It is a separate class from ITextSource to allow the GC to collect the text source while
/// the version checkpoint is still in use.
/// </remarks>
internal interface ITextSourceVersion
{
/// <summary>
/// Gets whether this checkpoint belongs to the same document as the other checkpoint.
/// </summary>
/// <remarks>
/// Returns false when given <c>null</c>.
/// </remarks>
bool BelongsToSameDocumentAs(ITextSourceVersion other);
/// <summary>
/// Compares the age of this checkpoint to the other checkpoint.
/// </summary>
/// <remarks>This method is thread-safe.</remarks>
/// <exception cref="ArgumentException">Raised if 'other' belongs to a different document than this version.</exception>
/// <returns>-1 if this version is older than <paramref name="other"/>.
/// 0 if <c>this</c> version instance represents the same version as <paramref name="other"/>.
/// 1 if this version is newer than <paramref name="other"/>.</returns>
int CompareAge(ITextSourceVersion other);
/// <summary>
/// Gets the changes from this checkpoint to the other checkpoint.
/// If 'other' is older than this checkpoint, reverse changes are calculated.
/// </summary>
/// <remarks>This method is thread-safe.</remarks>
/// <exception cref="ArgumentException">Raised if 'other' belongs to a different document than this checkpoint.</exception>
IEnumerable<TextChangeEventArgs> GetChangesTo(ITextSourceVersion other);
/// <summary>
/// Calculates where the offset has moved in the other buffer version.
/// </summary>
/// <exception cref="ArgumentException">Raised if 'other' belongs to a different document than this checkpoint.</exception>
int MoveOffsetTo(ITextSourceVersion other, int oldOffset, AnchorMovementType movement = AnchorMovementType.Default);
}
/// <summary>
/// Implements the ITextSource interface using a string.
/// </summary>
internal class StringTextSource : ITextSource
{
/// <summary>
/// Gets a text source containing the empty string.
/// </summary>
internal static readonly StringTextSource Empty = new StringTextSource(string.Empty);
/// <summary>
/// Creates a new StringTextSource with the given text.
/// </summary>
internal StringTextSource(string text)
{
Text = text ?? throw new ArgumentNullException(nameof(text));
}
/// <summary>
/// Creates a new StringTextSource with the given text.
/// </summary>
internal StringTextSource(string text, ITextSourceVersion version)
{
Text = text ?? throw new ArgumentNullException(nameof(text));
Version = version;
}
/// <inheritdoc/>
public ITextSourceVersion Version { get; }
/// <inheritdoc/>
public int TextLength => Text.Length;
/// <inheritdoc/>
public string Text { get; }
/// <inheritdoc/>
public ITextSource CreateSnapshot()
{
return this; // StringTextSource is immutable
}
/// <inheritdoc/>
public ITextSource CreateSnapshot(int offset, int length)
{
return new StringTextSource(Text.Substring(offset, length));
}
/// <inheritdoc/>
public TextReader CreateReader()
{
return new StringReader(Text);
}
/// <inheritdoc/>
public TextReader CreateReader(int offset, int length)
{
return new StringReader(Text.Substring(offset, length));
}
/// <inheritdoc/>
public void WriteTextTo(TextWriter writer)
{
writer.Write(Text);
}
/// <inheritdoc/>
public void WriteTextTo(TextWriter writer, int offset, int length)
{
writer.Write(Text.Substring(offset, length));
}
/// <inheritdoc/>
public char GetCharAt(int offset)
{
return Text[offset];
}
/// <inheritdoc/>
public string GetText(int offset, int length)
{
return Text.Substring(offset, length);
}
/// <inheritdoc/>
public ReadOnlyMemory<char> GetTextAsMemory(int offset, int length)
{
return Text.AsMemory(offset, length);
}
/// <inheritdoc/>
public string GetText(ISegment segment)
{
if (segment == null)
throw new ArgumentNullException(nameof(segment));
return Text.Substring(segment.Offset, segment.Length);
}
/// <inheritdoc/>
public int IndexOf(char c, int startIndex, int count)
{
return Text.IndexOf(c, startIndex, count);
}
/// <inheritdoc/>
public int IndexOfAny(char[] anyOf, int startIndex, int count)
{
return Text.IndexOfAny(anyOf, startIndex, count);
}
/// <inheritdoc/>
public int IndexOf(string searchText, int startIndex, int count, StringComparison comparisonType)
{
return Text.IndexOf(searchText, startIndex, count, comparisonType);
}
/// <inheritdoc/>
public int LastIndexOf(char c, int startIndex, int count)
{
return Text.LastIndexOf(c, startIndex + count - 1, count);
}
/// <inheritdoc/>
public int LastIndexOf(string searchText, int startIndex, int count, StringComparison comparisonType)
{
return Text.LastIndexOf(searchText, startIndex + count - 1, count, comparisonType);
}
}
}