source: branches/PersistenceReintegration/HeuristicLab.ExtLibs/HeuristicLab.AvalonEdit/5.0.1/AvalonEdit-5.0.1/Document/ITextSource.cs @ 14923

// 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
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// 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.Collections.Generic;
using System;
using System.IO;

namespace ICSharpCode.AvalonEdit.Document
{
  #if !NREFACTORY
  /// <summary>
  /// A read-only view on a (potentially mutable) text source.
  /// The IDocument interface derives from this interface.
  /// </summary>
  public 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>
    [System.Diagnostics.CodeAnalysis.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.
    /// </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>
  public 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>
  [Serializable]
  public class StringTextSource : ITextSource
  {
    /// <summary>
    /// Gets a text source containing the empty string.
    /// </summary>
    public static readonly StringTextSource Empty = new StringTextSource(string.Empty);
    
    readonly string text;
    readonly ITextSourceVersion version;
    
    /// <summary>
    /// Creates a new StringTextSource with the given text.
    /// </summary>
    public StringTextSource(string text)
    {
      if (text == null)
        throw new ArgumentNullException("text");
      this.text = text;
    }
    
    /// <summary>
    /// Creates a new StringTextSource with the given text.
    /// </summary>
    public StringTextSource(string text, ITextSourceVersion version)
    {
      if (text == null)
        throw new ArgumentNullException("text");
      this.text = text;
      this.version = version;
    }
    
    /// <inheritdoc/>
    public ITextSourceVersion Version {
      get { return version; }
    }
    
    /// <inheritdoc/>
    public int TextLength {
      get { return text.Length; }
    }
    
    /// <inheritdoc/>
    public string Text {
      get { return text; }
    }
    
    /// <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 string GetText(ISegment segment)
    {
      if (segment == null)
        throw new ArgumentNullException("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);
    }
  }
  #endif
}