diff --git a/native/src/defines.h b/native/src/defines.h
index ddd65c9fa7a363ca18d956e640f2854801b4af03..5d85b7c517d4ff80f82edd529e80af1d17deadb4 100644
--- a/native/src/defines.h
+++ b/native/src/defines.h
@@ -148,6 +148,10 @@ static void prof_out(void) {
#define MAX_DEPTH_MULTIPLIER 3
+// TODO: Reduce this constant if possible; check the maximum number of umlauts in the same German
+// word in the dictionary
+#define DEFAULT_MAX_UMLAUT_SEARCH_DEPTH 5
+
// Minimum suggest depth for one word for all cases except for missing space suggestions.
#define MIN_SUGGEST_DEPTH 1
#define MIN_USER_TYPED_LENGTH_FOR_MISSING_SPACE_SUGGESTION 3
diff --git a/native/src/unigram_dictionary.cpp b/native/src/unigram_dictionary.cpp
index 9aa36b064a4373592a891a9551122a7c1cd6c97d..b82910a40103887a47ed1e19686e408b227edc9a 100644
--- a/native/src/unigram_dictionary.cpp
+++ b/native/src/unigram_dictionary.cpp
@@ -41,7 +41,8 @@ UnigramDictionary::UnigramDictionary(const unsigned char *dict, int typedLetterM
MAX_PROXIMITY_CHARS(maxProximityChars), IS_LATEST_DICT_VERSION(isLatestDictVersion),
TYPED_LETTER_MULTIPLIER(typedLetterMultiplier), FULL_WORD_MULTIPLIER(fullWordMultiplier),
ROOT_POS(isLatestDictVersion ? DICTIONARY_HEADER_SIZE : 0),
- BYTES_IN_ONE_CHAR(MAX_PROXIMITY_CHARS * sizeof(*mInputCodes)) {
+ BYTES_IN_ONE_CHAR(MAX_PROXIMITY_CHARS * sizeof(*mInputCodes)),
+ MAX_UMLAUT_SEARCH_DEPTH(DEFAULT_MAX_UMLAUT_SEARCH_DEPTH) {
if (DEBUG_DICT) LOGI("UnigramDictionary - constructor");
}
@@ -80,30 +81,37 @@ bool UnigramDictionary::isDigraph(const int* codes, const int i, const int codes
void UnigramDictionary::getWordWithDigraphSuggestionsRec(const ProximityInfo *proximityInfo,
const int *xcoordinates, const int* ycoordinates, const int *codesBuffer,
const int codesBufferSize, const int flags, const int* codesSrc, const int codesRemain,
- int* codesDest, unsigned short* outWords, int* frequencies) {
-
- for (int i = 0; i < codesRemain; ++i) {
- if (isDigraph(codesSrc, i, codesRemain)) {
- // Found a digraph. We will try both spellings. eg. the word is "pruefen"
-
- // Copy the word up to the first char of the digraph, then continue processing
- // on the remaining part of the word, skipping the second char of the digraph.
- // In our example, copy "pru" and continue running on "fen"
- memcpy(codesDest, codesSrc, i * BYTES_IN_ONE_CHAR);
- getWordWithDigraphSuggestionsRec(proximityInfo, xcoordinates, ycoordinates, codesBuffer,
- codesBufferSize, flags, codesSrc + (i + 1) * MAX_PROXIMITY_CHARS,
- codesRemain - i - 1, codesDest + i * MAX_PROXIMITY_CHARS,
- outWords, frequencies);
-
- // Copy the second char of the digraph in place, then continue processing on
- // the remaining part of the word.
- // In our example, after "pru" in the buffer copy the "e", and continue running on "fen"
- memcpy(codesDest + i * MAX_PROXIMITY_CHARS, codesSrc + i * MAX_PROXIMITY_CHARS,
- BYTES_IN_ONE_CHAR);
- getWordWithDigraphSuggestionsRec(proximityInfo, xcoordinates, ycoordinates, codesBuffer,
- codesBufferSize, flags, codesSrc + i * MAX_PROXIMITY_CHARS, codesRemain - i,
- codesDest + i * MAX_PROXIMITY_CHARS, outWords, frequencies);
- return;
+ int currentDepth, int* codesDest, unsigned short* outWords, int* frequencies) {
+
+ if (currentDepth < MAX_UMLAUT_SEARCH_DEPTH) {
+ for (int i = 0; i < codesRemain; ++i) {
+ if (isDigraph(codesSrc, i, codesRemain)) {
+ // Found a digraph. We will try both spellings. eg. the word is "pruefen"
+
+ // Copy the word up to the first char of the digraph, then continue processing
+ // on the remaining part of the word, skipping the second char of the digraph.
+ // In our example, copy "pru" and continue running on "fen"
+ // Make i the index of the second char of the digraph for simplicity. Forgetting
+ // to do that results in an infinite recursion so take care!
+ ++i;
+ memcpy(codesDest, codesSrc, i * BYTES_IN_ONE_CHAR);
+ getWordWithDigraphSuggestionsRec(proximityInfo, xcoordinates, ycoordinates,
+ codesBuffer, codesBufferSize, flags,
+ codesSrc + (i + 1) * MAX_PROXIMITY_CHARS, codesRemain - i - 1,
+ currentDepth + 1, codesDest + i * MAX_PROXIMITY_CHARS, outWords,
+ frequencies);
+
+ // Copy the second char of the digraph in place, then continue processing on
+ // the remaining part of the word.
+ // In our example, after "pru" in the buffer copy the "e", and continue on "fen"
+ memcpy(codesDest + i * MAX_PROXIMITY_CHARS, codesSrc + i * MAX_PROXIMITY_CHARS,
+ BYTES_IN_ONE_CHAR);
+ getWordWithDigraphSuggestionsRec(proximityInfo, xcoordinates, ycoordinates,
+ codesBuffer, codesBufferSize, flags, codesSrc + i * MAX_PROXIMITY_CHARS,
+ codesRemain - i, currentDepth + 1, codesDest + i * MAX_PROXIMITY_CHARS,
+ outWords, frequencies);
+ return;
+ }
}
}
@@ -128,7 +136,7 @@ int UnigramDictionary::getSuggestions(const ProximityInfo *proximityInfo, const
{ // Incrementally tune the word and try all possibilities
int codesBuffer[getCodesBufferSize(codes, codesSize, MAX_PROXIMITY_CHARS)];
getWordWithDigraphSuggestionsRec(proximityInfo, xcoordinates, ycoordinates, codesBuffer,
- codesSize, flags, codes, codesSize, codesBuffer, outWords, frequencies);
+ codesSize, flags, codes, codesSize, 0, codesBuffer, outWords, frequencies);
} else { // Normal processing
getWordSuggestions(proximityInfo, xcoordinates, ycoordinates, codes, codesSize,
outWords, frequencies);
diff --git a/native/src/unigram_dictionary.h b/native/src/unigram_dictionary.h
index a95984520829e14e0726fda117913f73fb3f9215..8a4b40e0cd59a455c4051b4f572444f8fad8ec5b 100644
--- a/native/src/unigram_dictionary.h
+++ b/native/src/unigram_dictionary.h
@@ -46,7 +46,7 @@ private:
void getWordWithDigraphSuggestionsRec(const ProximityInfo *proximityInfo,
const int *xcoordinates, const int* ycoordinates, const int *codesBuffer,
const int codesBufferSize, const int flags, const int* codesSrc, const int codesRemain,
- int* codesDest, unsigned short* outWords, int* frequencies);
+ int currentDepth, int* codesDest, unsigned short* outWords, int* frequencies);
void initSuggestions(const int *codes, const int codesSize, unsigned short *outWords,
int *frequencies);
void getSuggestionCandidates(const int skipPos, const int excessivePos,
@@ -108,6 +108,7 @@ private:
const int FULL_WORD_MULTIPLIER;
const int ROOT_POS;
const unsigned int BYTES_IN_ONE_CHAR;
+ const unsigned int MAX_UMLAUT_SEARCH_DEPTH;
// Flags for special processing
// Those *must* match the flags in BinaryDictionary.Flags.ALL_FLAGS in BinaryDictionary.java