/// <summary>
/// Applies change in regular expression format to input string.
/// </summary>
/// <param name="input"></param>
/// <param name="options"></param>
/// <param name="exceptions"></param>
/// <returns></returns>
private string ApplyRegex(string input, ChangeOptions options, IList <Change> exceptions)
{
if (!IsReplacementApplicable())
{
return(input); //nedochází k žádné změně
}
//pravidla počtu nahrazení pro Regex: -1 = všechny výskyty; 0 = žádný výskyt; 1 a více = zadaný počet výskytů
//pravdila Cahnge: null, 0 = žádný výskyt
string output = input;
int replacementCount = GetReplacementCount(options);
Occurrences exceptionMatches = ExceptionMatches(input, exceptions);
if (exceptionMatches.Count == 0)
{
return(base.Regex.Replace(input, Replace, replacementCount));
}
MatchCollection patternMatches = base.Regex.Matches(input);
int count = 0;
output = input;
foreach (Match match in patternMatches)
{
Occurrence occurrence = new Occurrence(match.Index, match.Index + match.Length);
if (!exceptionMatches.IsOccurrenceWithin(occurrence))
{
output = base.Regex.Replace(output, Replace, 1, match.Index);
count++;
}
if (count == options.ReplacementCount)
{
return(output);
}
}
return(output);
}
private string Output(ChangeOptions options, int count, Occurrences exceptionMatches, string output)
{
int start = 0;
for (int i = 0; i < count; i++)
{
int loc = output.IndexOf(Pattern, start, StringComparison.Ordinal);
Occurrence occurrence = new Occurrence(loc, loc + Pattern.Length);
while (exceptionMatches.IsOccurrenceWithin(occurrence))
{
loc = output.IndexOf(Pattern, loc + 1, StringComparison.Ordinal);
occurrence = new Occurrence(loc, loc + Pattern.Length);
}
if (loc == -1)
{
return(output);
}
output = ReplaceFirstOccurrence(output, Pattern, Replace, options, loc);
start = loc + 1;
}
return(output);
}
