internal static WildcardElement Create(string pattern, ref int patternIndex)
{
if (patternIndex >= pattern.Length)
{
return(null);
}
switch (pattern[patternIndex])
{
case '*':
return(WildcardAsteriskElement.Create(pattern, ref patternIndex));
case '?':
return(WildcardQuestionElement.Create(pattern, ref patternIndex));
case '#':
return(WildcardSharpElement.Create(pattern, ref patternIndex));
case '[':
{
int startIndex = patternIndex;
WildcardElement element = WildcardRangeElement.Create(pattern, ref patternIndex);
if (element == null)
{
patternIndex = startIndex;
element = WildcardStringElement.Create(pattern, ref patternIndex);
}
return(element);
}
default:
return(WildcardStringElement.Create(pattern, ref patternIndex));
}
}
internal new static WildcardRangeElement Create(string pattern, ref int patternIndex)
{
patternIndex++;
int patternLength = pattern.Length;
bool negate = false;
var chars = new HashSet <char>();
if (patternIndex < patternLength && pattern[patternIndex] == '!')
{
patternIndex++;
negate = true;
}
bool closed = false;
while (patternIndex < patternLength)
{
char ch = pattern[patternIndex];
switch (ch)
{
case ']':
{
patternIndex++;
closed = true;
}
break;
case '\\':
{
patternIndex++;
if (patternIndex < patternLength)
{
ch = pattern[patternIndex++];
if (!chars.Contains(ch))
{
chars.Add(ch);
}
}
}
continue;
default:
{
if (char.IsLetter(ch))
{
patternIndex++;
if (patternIndex + 1 < patternLength &&
pattern[patternIndex] == '-' &&
char.IsLetter(pattern[patternIndex + 1]))
{
patternIndex++; // -
char fromChar = ch;
char toChar = pattern[patternIndex++];
for (char c = fromChar; c <= toChar; c++)
{
if (!chars.Contains(c))
{
chars.Add(c);
}
}
}
else
{
if (!chars.Contains(ch))
{
chars.Add(ch);
}
}
}
else if (char.IsDigit(ch))
{
patternIndex++;
if (patternIndex + 1 < patternLength &&
pattern[patternIndex] == '-' &&
char.IsDigit(pattern[patternIndex + 1]))
{
patternIndex++; // -
char fromChar = ch;
char toChar = pattern[patternIndex++];
for (char c = fromChar; c <= toChar; c++)
{
if (!chars.Contains(c))
{
chars.Add(c);
}
}
}
else
{
if (!chars.Contains(ch))
{
chars.Add(ch);
}
}
}
else
{
patternIndex++;
if (!chars.Contains(ch))
{
chars.Add(ch);
}
}
}
continue;
}
break;
}
if (!closed || chars.Count == 0)
{
return(null);
}
var element = new WildcardRangeElement();
element.Negate = negate;
element.Chars = chars;
element.Next = WildcardElement.Create(pattern, ref patternIndex);
return(element);
}
