81 lines
2.7 KiB
C#
81 lines
2.7 KiB
C#
// Copyright (c) Microsoft Corporation.
|
|
// Licensed under the MIT License.
|
|
|
|
using System.Threading;
|
|
using Markdig.Syntax;
|
|
|
|
namespace Microsoft.PowerShell.MarkdownRender
|
|
{
|
|
/// <summary>
|
|
/// Renderer for adding VT100 escape sequences for items in a list block.
|
|
/// </summary>
|
|
internal class ListItemBlockRenderer : VT100ObjectRenderer<ListItemBlock>
|
|
{
|
|
protected override void Write(VT100Renderer renderer, ListItemBlock obj)
|
|
{
|
|
if (obj.Parent is ListBlock parent)
|
|
{
|
|
if (!parent.IsOrdered)
|
|
{
|
|
foreach (var line in obj)
|
|
{
|
|
RenderWithIndent(renderer, line, parent.BulletType, 0);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
private void RenderWithIndent(VT100Renderer renderer, MarkdownObject block, char listBullet, int indentLevel)
|
|
{
|
|
// Indent left by 2 for each level on list.
|
|
string indent = Padding(indentLevel * 2);
|
|
|
|
if (block is ParagraphBlock paragraphBlock)
|
|
{
|
|
renderer.Write(indent).Write(listBullet).Write(" ").Write(paragraphBlock.Inline);
|
|
}
|
|
else
|
|
{
|
|
// If there is a sublist, the block is a ListBlock instead of ParagraphBlock.
|
|
if (block is ListBlock subList)
|
|
{
|
|
foreach (var subListItem in subList)
|
|
{
|
|
if (subListItem is ListItemBlock subListItemBlock)
|
|
{
|
|
foreach (var line in subListItemBlock)
|
|
{
|
|
// Increment indent level for sub list.
|
|
RenderWithIndent(renderer, line, listBullet, indentLevel + 1);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Typical padding is at most a screen's width, any more than that and we won't bother caching.
|
|
private const int IndentCacheMax = 120;
|
|
|
|
private static readonly string[] IndentCache = new string[IndentCacheMax];
|
|
|
|
internal static string Padding(int countOfSpaces)
|
|
{
|
|
if (countOfSpaces >= IndentCacheMax)
|
|
{
|
|
return new string(' ', countOfSpaces);
|
|
}
|
|
|
|
var result = IndentCache[countOfSpaces];
|
|
|
|
if (result == null)
|
|
{
|
|
Interlocked.CompareExchange(ref IndentCache[countOfSpaces], new string(' ', countOfSpaces), comparand: null);
|
|
result = IndentCache[countOfSpaces];
|
|
}
|
|
|
|
return result;
|
|
}
|
|
}
|
|
}
|