/// <inheritdoc />
public string Transform(string value)
{
char[] array;
// Slower path to not break formatting strings by removing their digits or break HTML tags
if (EscapeHelpers.MayNeedEscaping(value))
{
array = value.ToArray();
for (int i = 0; i < array.Length; i++)
{
char ch = array[i];
if (EscapeHelpers.ShouldTransform(array, ch, ref i))
{
array[i] = Transform(ch);
}
}
}
else
{
array = value.Select(Transform).ToArray();
}
return(new string(array));
}
/// <inheritdoc />
public string Transform(string value)
{
// Slower path to not break formatting strings by flipping placeholders or breaking HTML
if (EscapeHelpers.MayNeedEscaping(value))
{
return(MirrorSlow(value));
}
else
{
return(MirrorFast(value));
}
}
private static string MirrorSlow(string value)
{
char[] src = value.ToArray();
var result = new StringBuilder(value.Length);
var current = new StringBuilder(value.Length);
var startTag = new StringBuilder();
bool isInsideTag = false;
for (int i = 0; i < value.Length; i++)
{
char ch = value[i];
int indexBefore = i;
if (EscapeHelpers.ShouldTransform(src, ch, ref i, out var textType))
{
if (isInsideTag)
{
// Build the reversed inner text of the HTML tag
current.Insert(0, FlipIfSpecial(ch));
}
else
{
result.Insert(0, FlipIfSpecial(ch));
}
}
else
{
// Transformation should be skipped due to formatting placeholder or HTML
if (textType == EscapeHelpers.TextType.Format)
{
if (isInsideTag)
{
// Add the escaped string to the start of the
// inner text for the tag in left-to-right order
for (int j = indexBefore, k = 0; j < i + 1; j++, k++)
{
current.Insert(k, value[j]);
}
}
else
{
// Add the format string to the end in left-to-right order
for (int j = indexBefore; j < i + 1; j++)
{
current.Append(value[j]);
}
// Flush to the left-hand-side of the result
if (current.Length > 0)
{
result.Insert(0, current.ToString());
current.Clear();
}
}
}
else if (textType == EscapeHelpers.TextType.HtmlSelfClosing)
{
// Add the escaped string to the start
// of the result in left-to-right order
for (int j = indexBefore, k = 0; j < i + 1; j++, k++)
{
result.Insert(k, value[j]);
}
}
else if (textType == EscapeHelpers.TextType.HtmlStart)
{
// Store the start tag for use once it's closed
isInsideTag = true;
for (int j = indexBefore; j < i + 1; j++)
{
startTag.Append(value[j]);
}
}
else if (textType == EscapeHelpers.TextType.HtmlEnd)
{
// Add the tag start as a prefix to the inner text
current.Insert(0, startTag.ToString());
startTag.Clear();
// Add the tag end as a suffix to the inner text
for (int j = indexBefore; j < i + 1; j++)
{
current.Append(value[j]);
}
// Flush the tag to the result
if (current.Length > 0)
{
for (int j = current.Length - 1; j > -1; j--)
{
result.Insert(0, current[j]);
}
current.Clear();
}
isInsideTag = false;
}
}
}
// Flush any remaining characters
if (current.Length > 0)
{
result.Insert(0, current.ToString());
}
return(result.ToString());
}
