private IList <CharsRef> DoStem(char[] word, int length, bool caseVariant)
{
JCG.List <CharsRef> stems = new JCG.List <CharsRef>();
Int32sRef forms = dictionary.LookupWord(word, 0, length);
if (forms != null)
{
for (int i = 0; i < forms.Length; i += formStep)
{
bool checkKeepCase = caseVariant && dictionary.keepcase != -1;
bool checkNeedAffix = dictionary.needaffix != -1;
bool checkOnlyInCompound = dictionary.onlyincompound != -1;
if (checkKeepCase || checkNeedAffix || checkOnlyInCompound)
{
dictionary.flagLookup.Get(forms.Int32s[forms.Offset + i], scratch);
char[] wordFlags = Dictionary.DecodeFlags(scratch);
// we are looking for a case variant, but this word does not allow it
if (checkKeepCase && Dictionary.HasFlag(wordFlags, (char)dictionary.keepcase))
{
continue;
}
// we can't add this form, its a pseudostem requiring an affix
if (checkNeedAffix && Dictionary.HasFlag(wordFlags, (char)dictionary.needaffix))
{
continue;
}
// we can't add this form, it only belongs inside a compound word
if (checkOnlyInCompound && Dictionary.HasFlag(wordFlags, (char)dictionary.onlyincompound))
{
continue;
}
}
stems.Add(NewStem(word, length, forms, i));
}
}
try
{
stems.AddRange(Stem(word, length, -1, -1, -1, 0, true, true, false, false, caseVariant));
}
catch (Exception bogus) when(bogus.IsIOException())
{
throw RuntimeException.Create(bogus);
}
return(stems);
}
/// <summary>
/// Applies the affix rule to the given word, producing a list of stems if any are found
/// </summary>
/// <param name="strippedWord"> Word the affix has been removed and the strip added </param>
/// <param name="length"> valid length of stripped word </param>
/// <param name="affix"> HunspellAffix representing the affix rule itself </param>
/// <param name="prefixFlag"> when we already stripped a prefix, we cant simply recurse and check the suffix, unless both are compatible
/// so we must check dictionary form against both to add it as a stem! </param>
/// <param name="recursionDepth"> current recursion depth </param>
/// <param name="prefix"> true if we are removing a prefix (false if its a suffix) </param>
/// <returns> List of stems for the word, or an empty list if none are found </returns>
internal IList <CharsRef> ApplyAffix(char[] strippedWord, int length, int affix, int prefixFlag, int recursionDepth, bool prefix, bool circumfix)
{
// TODO: just pass this in from before, no need to decode it twice
affixReader.Position = 8 * affix;
char flag = (char)(affixReader.ReadShort() & 0xffff);
affixReader.SkipBytes(2); // strip
int condition = (char)(affixReader.ReadShort() & 0xffff);
bool crossProduct = (condition & 1) == 1;
condition = (int)((uint)condition >> 1);
char append = (char)(affixReader.ReadShort() & 0xffff);
List <CharsRef> stems = new List <CharsRef>();
IntsRef forms = dictionary.LookupWord(strippedWord, 0, length);
if (forms != null)
{
for (int i = 0; i < forms.Length; i++)
{
dictionary.flagLookup.Get(forms.Ints[forms.Offset + i], scratch);
char[] wordFlags = Dictionary.DecodeFlags(scratch);
if (Dictionary.HasFlag(wordFlags, flag))
{
// confusing: in this one exception, we already chained the first prefix against the second,
// so it doesnt need to be checked against the word
bool chainedPrefix = dictionary.complexPrefixes && recursionDepth == 1 && prefix;
if (chainedPrefix == false && prefixFlag >= 0 && !Dictionary.HasFlag(wordFlags, (char)prefixFlag))
{
// see if we can chain prefix thru the suffix continuation class (only if it has any!)
dictionary.flagLookup.Get(append, scratch);
char[] appendFlags = Dictionary.DecodeFlags(scratch);
if (!HasCrossCheckedFlag((char)prefixFlag, appendFlags, false))
{
continue;
}
}
// if circumfix was previously set by a prefix, we must check this suffix,
// to ensure it has it, and vice versa
if (dictionary.circumfix != -1)
{
dictionary.flagLookup.Get(append, scratch);
char[] appendFlags = Dictionary.DecodeFlags(scratch);
bool suffixCircumfix = Dictionary.HasFlag(appendFlags, (char)dictionary.circumfix);
if (circumfix != suffixCircumfix)
{
continue;
}
}
stems.Add(NewStem(strippedWord, length));
}
}
}
// if a circumfix flag is defined in the dictionary, and we are a prefix, we need to check if we have that flag
if (dictionary.circumfix != -1 && !circumfix && prefix)
{
dictionary.flagLookup.Get(append, scratch);
char[] appendFlags = Dictionary.DecodeFlags(scratch);
circumfix = Dictionary.HasFlag(appendFlags, (char)dictionary.circumfix);
}
if (crossProduct)
{
if (recursionDepth == 0)
{
if (prefix)
{
// we took away the first prefix.
// COMPLEXPREFIXES = true: combine with a second prefix and another suffix
// COMPLEXPREFIXES = false: combine with a suffix
stems.AddRange(Stem(strippedWord, length, affix, flag, flag, ++recursionDepth, dictionary.complexPrefixes && dictionary.twoStageAffix, true, true, circumfix));
}
else if (dictionary.complexPrefixes == false && dictionary.twoStageAffix)
{
// we took away a suffix.
// COMPLEXPREFIXES = true: we don't recurse! only one suffix allowed
// COMPLEXPREFIXES = false: combine with another suffix
stems.AddRange(Stem(strippedWord, length, affix, flag, prefixFlag, ++recursionDepth, false, true, false, circumfix));
}
}
else if (recursionDepth == 1)
{
if (prefix && dictionary.complexPrefixes)
{
// we took away the second prefix: go look for another suffix
stems.AddRange(Stem(strippedWord, length, affix, flag, flag, ++recursionDepth, false, true, true, circumfix));
}
else if (prefix == false && dictionary.complexPrefixes == false && dictionary.twoStageAffix)
{
// we took away a prefix, then a suffix: go look for another suffix
stems.AddRange(Stem(strippedWord, length, affix, flag, prefixFlag, ++recursionDepth, false, true, false, circumfix));
}
}
}
return(stems);
}
/// <summary>
/// Generates a list of stems for the provided word
/// </summary>
/// <param name="word"> Word to generate the stems for </param>
/// <param name="length"> length </param>
/// <param name="previous"> previous affix that was removed (so we dont remove same one twice) </param>
/// <param name="prevFlag"> Flag from a previous stemming step that need to be cross-checked with any affixes in this recursive step </param>
/// <param name="prefixFlag"> flag of the most inner removed prefix, so that when removing a suffix, its also checked against the word </param>
/// <param name="recursionDepth"> current recursiondepth </param>
/// <param name="doPrefix"> true if we should remove prefixes </param>
/// <param name="doSuffix"> true if we should remove suffixes </param>
/// <param name="previousWasPrefix"> true if the previous removal was a prefix:
/// if we are removing a suffix, and it has no continuation requirements, its ok.
/// but two prefixes (COMPLEXPREFIXES) or two suffixes must have continuation requirements to recurse. </param>
/// <param name="circumfix"> true if the previous prefix removal was signed as a circumfix
/// this means inner most suffix must also contain circumfix flag. </param>
/// <param name="caseVariant"> true if we are searching for a case variant. if the word has KEEPCASE flag it cannot succeed. </param>
/// <returns> <see cref="IList{CharsRef}"/> of stems, or empty list if no stems are found </returns>
private IList <CharsRef> Stem(char[] word, int length, int previous, int prevFlag, int prefixFlag, int recursionDepth, bool doPrefix, bool doSuffix, bool previousWasPrefix, bool circumfix, bool caseVariant)
{
// TODO: allow this stuff to be reused by tokenfilter
JCG.List <CharsRef> stems = new JCG.List <CharsRef>();
if (doPrefix && dictionary.prefixes != null)
{
FST <Int32sRef> fst = dictionary.prefixes;
Outputs <Int32sRef> outputs = fst.Outputs;
FST.BytesReader bytesReader = prefixReaders[recursionDepth];
FST.Arc <Int32sRef> arc = prefixArcs[recursionDepth];
fst.GetFirstArc(arc);
Int32sRef NO_OUTPUT = outputs.NoOutput;
Int32sRef output = NO_OUTPUT;
int limit = dictionary.fullStrip ? length : length - 1;
for (int i = 0; i < limit; i++)
{
if (i > 0)
{
int ch = word[i - 1];
if (fst.FindTargetArc(ch, arc, arc, bytesReader) == null)
{
break;
}
else if (arc.Output != NO_OUTPUT)
{
output = fst.Outputs.Add(output, arc.Output);
}
}
Int32sRef prefixes; // LUCENENET: IDE0059 - Removed unnecessary value assignment
if (!arc.IsFinal)
{
continue;
}
else
{
prefixes = fst.Outputs.Add(output, arc.NextFinalOutput);
}
for (int j = 0; j < prefixes.Length; j++)
{
int prefix = prefixes.Int32s[prefixes.Offset + j];
if (prefix == previous)
{
continue;
}
affixReader.Position = 8 * prefix;
char flag = (char)(affixReader.ReadInt16() & 0xffff);
char stripOrd = (char)(affixReader.ReadInt16() & 0xffff);
int condition = (char)(affixReader.ReadInt16() & 0xffff);
bool crossProduct = (condition & 1) == 1;
condition = condition.TripleShift(1);
char append = (char)(affixReader.ReadInt16() & 0xffff);
bool compatible;
if (recursionDepth == 0)
{
if (dictionary.onlyincompound == -1)
{
compatible = true;
}
else
{
// check if affix is allowed in a non-compound word
dictionary.flagLookup.Get(append, scratch);
char[] appendFlags = Dictionary.DecodeFlags(scratch);
compatible = !Dictionary.HasFlag(appendFlags, (char)dictionary.onlyincompound);
}
}
else if (crossProduct)
{
// cross check incoming continuation class (flag of previous affix) against list.
dictionary.flagLookup.Get(append, scratch);
char[] appendFlags = Dictionary.DecodeFlags(scratch);
if (Debugging.AssertsEnabled)
{
Debugging.Assert(prevFlag >= 0);
}
bool allowed = dictionary.onlyincompound == -1 ||
!Dictionary.HasFlag(appendFlags, (char)dictionary.onlyincompound);
compatible = allowed && HasCrossCheckedFlag((char)prevFlag, appendFlags, false);
}
else
{
compatible = false;
}
if (compatible)
{
int deAffixedStart = i;
int deAffixedLength = length - deAffixedStart;
int stripStart = dictionary.stripOffsets[stripOrd];
int stripEnd = dictionary.stripOffsets[stripOrd + 1];
int stripLength = stripEnd - stripStart;
if (!CheckCondition(condition, dictionary.stripData, stripStart, stripLength, word, deAffixedStart, deAffixedLength))
{
continue;
}
char[] strippedWord = new char[stripLength + deAffixedLength];
Array.Copy(dictionary.stripData, stripStart, strippedWord, 0, stripLength);
Array.Copy(word, deAffixedStart, strippedWord, stripLength, deAffixedLength);
IList <CharsRef> stemList = ApplyAffix(strippedWord, strippedWord.Length, prefix, -1, recursionDepth, true, circumfix, caseVariant);
stems.AddRange(stemList);
}
}
}
}
if (doSuffix && dictionary.suffixes != null)
{
FST <Int32sRef> fst = dictionary.suffixes;
Outputs <Int32sRef> outputs = fst.Outputs;
FST.BytesReader bytesReader = suffixReaders[recursionDepth];
FST.Arc <Int32sRef> arc = suffixArcs[recursionDepth];
fst.GetFirstArc(arc);
Int32sRef NO_OUTPUT = outputs.NoOutput;
Int32sRef output = NO_OUTPUT;
int limit = dictionary.fullStrip ? 0 : 1;
for (int i = length; i >= limit; i--)
{
if (i < length)
{
int ch = word[i];
if (fst.FindTargetArc(ch, arc, arc, bytesReader) == null)
{
break;
}
else if (arc.Output != NO_OUTPUT)
{
output = fst.Outputs.Add(output, arc.Output);
}
}
Int32sRef suffixes; // LUCENENET: IDE0059 - Removed unnecessary value assignment
if (!arc.IsFinal)
{
continue;
}
else
{
suffixes = fst.Outputs.Add(output, arc.NextFinalOutput);
}
for (int j = 0; j < suffixes.Length; j++)
{
int suffix = suffixes.Int32s[suffixes.Offset + j];
if (suffix == previous)
{
continue;
}
affixReader.Position = 8 * suffix;
char flag = (char)(affixReader.ReadInt16() & 0xffff);
char stripOrd = (char)(affixReader.ReadInt16() & 0xffff);
int condition = (char)(affixReader.ReadInt16() & 0xffff);
bool crossProduct = (condition & 1) == 1;
condition = condition.TripleShift(1);
char append = (char)(affixReader.ReadInt16() & 0xffff);
bool compatible;
if (recursionDepth == 0)
{
if (dictionary.onlyincompound == -1)
{
compatible = true;
}
else
{
// check if affix is allowed in a non-compound word
dictionary.flagLookup.Get(append, scratch);
char[] appendFlags = Dictionary.DecodeFlags(scratch);
compatible = !Dictionary.HasFlag(appendFlags, (char)dictionary.onlyincompound);
}
}
else if (crossProduct)
{
// cross check incoming continuation class (flag of previous affix) against list.
dictionary.flagLookup.Get(append, scratch);
char[] appendFlags = Dictionary.DecodeFlags(scratch);
if (Debugging.AssertsEnabled)
{
Debugging.Assert(prevFlag >= 0);
}
bool allowed = dictionary.onlyincompound == -1 ||
!Dictionary.HasFlag(appendFlags, (char)dictionary.onlyincompound);
compatible = HasCrossCheckedFlag((char)prevFlag, appendFlags, previousWasPrefix);
}
else
{
compatible = false;
}
if (compatible)
{
int appendLength = length - i;
int deAffixedLength = length - appendLength;
int stripStart = dictionary.stripOffsets[stripOrd];
int stripEnd = dictionary.stripOffsets[stripOrd + 1];
int stripLength = stripEnd - stripStart;
if (!CheckCondition(condition, word, 0, deAffixedLength, dictionary.stripData, stripStart, stripLength))
{
continue;
}
char[] strippedWord = new char[stripLength + deAffixedLength];
Array.Copy(word, 0, strippedWord, 0, deAffixedLength);
Array.Copy(dictionary.stripData, stripStart, strippedWord, deAffixedLength, stripLength);
IList <CharsRef> stemList = ApplyAffix(strippedWord, strippedWord.Length, suffix, prefixFlag, recursionDepth, false, circumfix, caseVariant);
stems.AddRange(stemList);
}
}
}
}
return(stems);
}