private bool TryToCheckSubRegions(KeLexerState state, RegionSearchState mainRegionState)
{
var currentParsedString = state.CurrentParsedString;
while (true)
{
if (!state.CharEnumerator.MoveNextWhileWhiteSpace())
{
return(false);
}
var currentChar = state.CharEnumerator.Current.Value;
state.CharEnumerator.MoveNext();
var nextChar = state.CharEnumerator.Current;
var mainRegionCheckResult = mainRegionState.RegionRule.Check(currentChar, nextChar, currentParsedString);
if (mainRegionCheckResult.HasFlag(RuleCheckResult.Found))
{
mainRegionState.Index = mainRegionState.Index;
mainRegionState.AddSymbol(currentChar, mainRegionCheckResult);
mainRegionState.SetLastCheckResult(mainRegionCheckResult);
return(true);
}
state.CharEnumerator.SetIndex(state.CharEnumerator.Index - 1);
var subRegion = this.FindNextRegion(state);
if (subRegion is null)
{
return(mainRegionCheckResult.HasFlag(RuleCheckResult.Found));
}
mainRegionState.AddSubRegion(subRegion);
}
}
/// <summary>
///
/// </summary>
/// <param name="state"></param>
/// <returns></returns>
/// <remarks>Char enumerator should be setted on next symbol after region.</remarks>
private RegionSearchState FindNextRegion(KeLexerState state)
{
var currentChar = state.CharEnumerator.Current.Value;
state.CharEnumerator.MoveNext();
var nextChar = state.CharEnumerator.Current;
List <RegionSearchState> possibleRegions = new List <RegionSearchState>();
foreach (var regionRule in this.RegionRules)
{
var checkResult = regionRule.Check(currentChar, nextChar, string.Empty);
if (checkResult.HasFlag(RuleCheckResult.NotFound))
{
continue;
}
var regionToken = new RegionSearchState(regionRule)
{
Index = state.CharEnumerator.Index
};
regionToken.AddSymbol(currentChar, checkResult);
regionToken.SetLastCheckResult(checkResult);
possibleRegions.Add(regionToken);
}
if (possibleRegions.Count == 0)
{
return(null);
}
if (possibleRegions.Count == 1 && possibleRegions[0].LastCheckResult.HasFlag(RuleCheckResult.Found))
{
return(possibleRegions[0]);
}
state.CurrentParsedString = currentChar.ToString();
var foundedRegion = this.ObserveToSeveralRegions(state, possibleRegions);
if (foundedRegion is null)
{
return(null);
}
return(foundedRegion);
}