/// <summary>
/// Adds the given <paramref name="token"/> to pattern token sequence.
/// </summary>
/// <param name="token">Token to add</param>
private void AddToken(IInstructionPatternToken token)
{
iInstructionTokens.Add(token);
}
/// <summary>
/// Evaluates the given <paramref name="instruction"/> using the given <paramref name="instructionInfo"/>. Any resolved parameter is added
/// to <paramref name="paramCache"/>.
/// </summary>
/// <param name="instruction">Directive to evaluate</param>
/// <param name="instructionInfo">Instruction that provides the meta data</param>
/// <param name="paramCache">Parameter cache</param>
/// <returns>Evaluation result</returns>
public IInstructionEvaluationResult Evaluate(string instruction, InstructionTranslationInfo instructionInfo, IDictionary <string, IPatternParameter> paramCache)
{
if (string.IsNullOrEmpty(instruction))
{
throw new ArgumentNullException(nameof(instruction));
}
if (instructionInfo == null)
{
throw new ArgumentNullException(nameof(instructionInfo));
}
string wordSequence = instruction;
// Remove dot
if (wordSequence.EndsWith("."))
{
wordSequence = wordSequence.Substring(0, wordSequence.Length - 1);
}
// Value sequence recognition
string valueSequenceString = null;
wordSequence = Regex.Replace(wordSequence,
@"(?<top>""[^""]+"")(?<nav>\s(?<child>""[^""]+""))*\s(?<value>""[^""]+"")",
match => {
string prime = match.Groups["top"].Value;
string sslValue = string.Join(", ", match.Groups["child"].Captures.ToArray());
string value = match.Groups["value"].Value;
string[] joinSet = string.IsNullOrEmpty(sslValue) ? new[] { prime, value } : new[] { prime, sslValue, value };
valueSequenceString = string.Join(", ", joinSet);
return(ValueSequenceToken);
});
// Split to words
string[] words = wordSequence.SplitToBuddyTokens();
if (words.Length == 0)
{
return(EvaluationResult.Error(wordSequence, instructionInfo.Instruction, "Instruction is empty after split"));
}
words = words.StripSpecialCharacters();
if (words.Length == 0)
{
return(EvaluationResult.Error(wordSequence, instructionInfo.Instruction, "Instruction is empty after strip"));
}
// Normalize variants
if (instructionInfo.Instruction is IVariantInstruction variantInstruction)
{
words = variantInstruction.Normalize(words);
}
// Iterate words and check for match
int wordIndex = 0;
for (IEnumerator <IInstructionPatternToken> tokenItr = instructionInfo.GetInstructionPatternTokenEnumerator(); tokenItr.MoveNext();)
{
IInstructionPatternToken token = tokenItr.Current;
if (token == null)
{
throw new InvalidOperationException("Token iterator provided NULL token");
}
string word;
// Take the word from the sequence
if (wordIndex < words.Length)
{
word = words[wordIndex];
}
else // We have more tokens than words
// All remaining tokens must be not mandatory or we have an error
// So they must handle an unset value
{
word = PatternParameter.Unset;
}
// If we have a match, everything is fine
if (token.DoesMatch(word))
{
wordIndex++;
// Resolve parametrized tokens
if (token is IParametrizedInstructionPatternToken parametrizedToken)
{
IPatternParameter patternParameter = parametrizedToken.Value;
string parameterName = patternParameter.Name;
// If the value has been replaced by a ValueSequenceToken before, we have to re-replace it now
if (valueSequenceString != null) // Something must have been replaced
{
if (patternParameter.Value.Value.Equals(ValueSequenceToken)) // Is this the correct parameter?
{
((AbstractPatternParameter)patternParameter).SetValue(valueSequenceString);
}
}
// Add value to cache
paramCache.Add(parameterName, patternParameter);
}
continue;
}
// If the token is not mandatory, we can go forward
if (!token.IsMandatory)
{
continue;
}
return(EvaluationResult.Error(
wordSequence,
instructionInfo.Instruction,
$"{FormatWordIndex(wordIndex)} word of instruction " +
$"does not match expected token '{token.ToHumanReadableString()}'. " +
$"Word is '{word}'"
));
}
return(EvaluationResult.Ok);
}
