/// <summary>
/// Retrieves matching entries for a target-language search expression.
/// </summary>
private List <CedictResult> doTargetLookup(BinReader br, string query)
{
// Empty query string: no results
query = query.Trim();
if (query == string.Empty)
{
return(new List <CedictResult>());
}
// Tokenize query string
HybridText txtQuery = new HybridText(query);
ReadOnlyCollection <EquivToken> txtTokenized = tokenizer.Tokenize(txtQuery);
// Get query string's token IDs
bool anyUnknown = false;
HashSet <int> idSet = new HashSet <int>();
foreach (EquivToken eqt in txtTokenized)
{
if (eqt.TokenId == WordHolder.IdUnknown || eqt.TokenId == index.WordHolder.IdZho)
{
anyUnknown = true; break;
}
idSet.Add(eqt.TokenId);
}
// Any unknown tokens - no match, we know that immediately
List <CedictResult> res = new List <CedictResult>();
if (anyUnknown)
{
return(res);
}
// Collect IDs of tokenized senses that contain one or more of our query IDs
Dictionary <int, SenseLookupInfo> senseTokenCounts = new Dictionary <int, SenseLookupInfo>();
bool firstToken = true;
// For each token...
foreach (int tokenId in idSet)
{
// Get sense instances where it occurs
List <SenseInfo> instances = index.SenseIndex[tokenId].GetOrLoadInstances(br);
foreach (SenseInfo si in instances)
{
SenseLookupInfo sli;
// We already have a count for this token ID
if (senseTokenCounts.ContainsKey(si.TokenizedSenseId))
{
++senseTokenCounts[si.TokenizedSenseId].NumOfQueryTokensInSense;
}
// Or this is the first time we're seeing it
// We only record counts for the first token
// We're looking for senses that contain *all* query tokens
else if (firstToken)
{
sli = new SenseLookupInfo
{
NumOfQueryTokensInSense = 0,
TokensInSense = si.TokensInSense
};
senseTokenCounts[si.TokenizedSenseId] = sli;
++sli.NumOfQueryTokensInSense;
}
}
firstToken = false;
}
// Keep those sense IDs (positions) that contain all of our query tokens
// We already eliminated some candidates through "firstToken" trick before, but not all
List <int> sensePosList = new List <int>();
foreach (var x in senseTokenCounts)
{
if (x.Value.NumOfQueryTokensInSense == idSet.Count)
{
sensePosList.Add(x.Key);
}
}
// Load each tokenized sense to find out:
// - whether entry is a real match
// - entry ID
// - best score for entry (multiple senses may hold query string)
// - highlights
Dictionary <int, EntryMatchInfo> entryIdToInfo = new Dictionary <int, EntryMatchInfo>();
foreach (int senseId in sensePosList)
{
doVerifyTarget(txtTokenized, senseId, entryIdToInfo, br);
}
// Sort entry IDs by their best score
// Drop entries with unprintable hanzi in HW now
List <EntryMatchInfo> entryInfoList = new List <EntryMatchInfo>();
foreach (var x in entryIdToInfo)
{
// Check coverage. Because we don't load full entry, it's possible
// that some unsupported chars in hybrid text of senses slip through.
// There's a limit to perfectionism.
string simp, trad;
br.Position = x.Value.EntryId;
CedictEntry.DeserializeHanzi(br, out simp, out trad);
if (!areHanziCovered(simp, trad))
{
continue;
}
// Queue up for sorting.
entryInfoList.Add(x.Value);
}
entryInfoList.Sort((a, b) => b.BestSenseScore.CompareTo(a.BestSenseScore));
// Load entries, wrap into results
foreach (EntryMatchInfo emi in entryInfoList)
{
CedictResult cr = new CedictResult(emi.EntryId,
new ReadOnlyCollection <CedictTargetHighlight>(emi.TargetHilites));
res.Add(cr);
}
return(res);
}