// 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.IO;
namespace Unity.CodeEditor.Utils
{
/// <summary>
/// Poor man's template specialization: extension methods for Rope<char>.
/// </summary>
internal static class CharRope
{
/// <summary>
/// Creates a new rope from the specified text.
/// </summary>
internal static Rope<char> Create(string text)
{
if (text == null)
throw new ArgumentNullException(nameof(text));
return new Rope<char>(InitFromString(text));
}
/// <summary>
/// Retrieves the text for a portion of the rope.
/// Runs in O(lg N + M), where M=<paramref name="length"/>.
/// </summary>
/// <exception cref="ArgumentOutOfRangeException">offset or length is outside the valid range.</exception>
/// <remarks>
/// This method counts as a read access and may be called concurrently to other read accesses.
/// </remarks>
internal static string ToString(this Rope<char> rope, int startIndex, int length)
{
if (rope == null)
throw new ArgumentNullException(nameof(rope));
#if DEBUG
if (length < 0)
throw new ArgumentOutOfRangeException(nameof(length), length, "Value must be >= 0");
#endif
if (length == 0)
return string.Empty;
char[] buffer = new char[length];
rope.CopyTo(startIndex, buffer, 0, length);
return new string(buffer);
}
/// <summary>
/// Retrieves the text for a portion of the rope as ReadOnlyMemory.
/// Runs in O(lg N + M), where M=<paramref name="length"/>.
/// </summary>
/// <exception cref="ArgumentOutOfRangeException">offset or length is outside the valid range.</exception>
/// <remarks>
/// This method counts as a read access and may be called concurrently to other read accesses.
/// When the requested range falls entirely within a single leaf node, this method returns
/// a slice of the internal buffer without allocation. Otherwise, a new buffer is allocated.
/// </remarks>
internal static ReadOnlyMemory<char> GetMemory(this Rope<char> rope, int startIndex, int length)
{
if (rope == null)
throw new ArgumentNullException(nameof(rope));
if (length < 0)
throw new ArgumentOutOfRangeException(nameof(length), length, "Value must be >= 0");
if (length == 0)
return ReadOnlyMemory<char>.Empty;
rope.VerifyRange(startIndex, length);
// Try to get a zero-allocation slice if the range fits within a single leaf node
var entry = rope.FindNodeUsingCache(startIndex).PeekOrDefault();
int offsetWithinNode = startIndex - entry.NodeStartIndex;
// Check if the entire requested range fits within this leaf node
if (offsetWithinNode + length <= entry.Node.Length)
{
// Return a slice of the existing buffer - no allocation needed
return new ReadOnlyMemory<char>(entry.Node.Contents, offsetWithinNode, length);
}
// Range spans multiple nodes - must allocate and copy
char[] buffer = new char[length];
rope.CopyTo(startIndex, buffer, 0, length);
return new ReadOnlyMemory<char>(buffer);
}
/// <summary>
/// Retrieves the text for a portion of the rope and writes it to the specified text writer.
/// Runs in O(lg N + M), where M=<paramref name="length"/>.
/// </summary>
/// <exception cref="ArgumentOutOfRangeException">offset or length is outside the valid range.</exception>
/// <remarks>
/// This method counts as a read access and may be called concurrently to other read accesses.
/// </remarks>
internal static void WriteTo(this Rope<char> rope, TextWriter output, int startIndex, int length)
{
if (rope == null)
throw new ArgumentNullException(nameof(rope));
if (output == null)
throw new ArgumentNullException(nameof(output));
rope.VerifyRange(startIndex, length);
rope.Root.WriteTo(startIndex, output, length);
}
/// <summary>
/// Appends text to this rope.
/// Runs in O(lg N + M).
/// </summary>
/// <exception cref="ArgumentNullException">newElements is null.</exception>
internal static void AddText(this Rope<char> rope, string text)
{
InsertText(rope, rope.Length, text);
}
/// <summary>
/// Inserts text into this rope.
/// Runs in O(lg N + M).
/// </summary>
/// <exception cref="ArgumentNullException">newElements is null.</exception>
/// <exception cref="ArgumentOutOfRangeException">index or length is outside the valid range.</exception>
internal static void InsertText(this Rope<char> rope, int index, string text)
{
if (rope == null)
throw new ArgumentNullException(nameof(rope));
rope.InsertRange(index, text.ToCharArray(), 0, text.Length);
/*if (index < 0 || index > rope.Length) {
throw new ArgumentOutOfRangeException("index", index, "0 <= index <= " + rope.Length.ToString(CultureInfo.InvariantCulture));
}
if (text == null)
throw new ArgumentNullException("text");
if (text.Length == 0)
return;
rope.root = rope.root.Insert(index, text);
rope.OnChanged();*/
}
internal static RopeNode<char> InitFromString(string text)
{
if (text.Length == 0) {
return RopeNode<char>.EmptyRopeNode;
}
RopeNode<char> node = RopeNode<char>.CreateNodes(text.Length);
FillNode(node, text, 0);
return node;
}
static void FillNode(RopeNode<char> node, string text, int start)
{
if (node.Contents != null) {
text.CopyTo(start, node.Contents, 0, node.Length);
} else {
FillNode(node.Left, text, start);
FillNode(node.Right, text, start + node.Left.Length);
}
}
internal static void WriteTo(this RopeNode<char> node, int index, TextWriter output, int count)
{
if (node.Height == 0) {
if (node.Contents == null) {
// function node
node.GetContentNode().WriteTo(index, output, count);
} else {
// leaf node: append data
output.Write(node.Contents, index, count);
}
} else {
// concat node: do recursive calls
if (index + count <= node.Left.Length) {
node.Left.WriteTo(index, output, count);
} else if (index >= node.Left.Length) {
node.Right.WriteTo(index - node.Left.Length, output, count);
} else {
int amountInLeft = node.Left.Length - index;
node.Left.WriteTo(index, output, amountInLeft);
node.Right.WriteTo(0, output, count - amountInLeft);
}
}
}
/// <summary>
/// Gets the index of the first occurrence of any element in the specified array.
/// </summary>
/// <param name="rope">The target rope.</param>
/// <param name="anyOf">Array of characters being searched.</param>
/// <param name="startIndex">Start index of the search.</param>
/// <param name="length">Length of the area to search.</param>
/// <returns>The first index where any character was found; or -1 if no occurrence was found.</returns>
internal static int IndexOfAny(this Rope<char> rope, char[] anyOf, int startIndex, int length)
{
if (rope == null)
throw new ArgumentNullException(nameof(rope));
if (anyOf == null)
throw new ArgumentNullException(nameof(anyOf));
rope.VerifyRange(startIndex, length);
while (length > 0) {
var entry = rope.FindNodeUsingCache(startIndex).Peek();
char[] contents = entry.Node.Contents;
int startWithinNode = startIndex - entry.NodeStartIndex;
int nodeLength = Math.Min(entry.Node.Length, startWithinNode + length);
for (int i = startIndex - entry.NodeStartIndex; i < nodeLength; i++) {
char element = contents[i];
foreach (char needle in anyOf) {
if (element == needle)
return entry.NodeStartIndex + i;
}
}
length -= nodeLength - startWithinNode;
startIndex = entry.NodeStartIndex + nodeLength;
}
return -1;
}
/// <summary>
/// Gets the index of the first occurrence of the search text.
/// </summary>
internal static int IndexOf(this Rope<char> rope, string searchText, int startIndex, int length, StringComparison comparisonType)
{
if (rope == null)
throw new ArgumentNullException(nameof(rope));
if (searchText == null)
throw new ArgumentNullException(nameof(searchText));
rope.VerifyRange(startIndex, length);
int pos = rope.ToString(startIndex, length).IndexOf(searchText, comparisonType);
if (pos < 0)
return -1;
else
return pos + startIndex;
}
/// <summary>
/// Gets the index of the last occurrence of the search text.
/// </summary>
internal static int LastIndexOf(this Rope<char> rope, string searchText, int startIndex, int length, StringComparison comparisonType)
{
if (rope == null)
throw new ArgumentNullException(nameof(rope));
if (searchText == null)
throw new ArgumentNullException(nameof(searchText));
rope.VerifyRange(startIndex, length);
int pos = rope.ToString(startIndex, length).LastIndexOf(searchText, comparisonType);
if (pos < 0)
return -1;
else
return pos + startIndex;
}
}
}