public void MarkWordBoundariesTest()
{
String title = String.Format("fear{0}is{0}the{0}mind{0}killer", Normalizer.WORD_SEPARATOR);
String search = "fmik";
int[] searchPositions = Scorer.FindRightmostCharPositions(title, search);
SearchCharFlags[] searchCharFlags = new SearchCharFlags[searchPositions.Length];
Scorer.MarkWordBoundaries(title, search, searchPositions, out searchCharFlags);
Assert.AreEqual(SearchCharFlags.WordBoundary, searchCharFlags[0]);
Assert.AreEqual(SearchCharFlags.WordBoundary, searchCharFlags[1]);
Assert.AreEqual(SearchCharFlags.None, searchCharFlags[2]);
Assert.AreEqual(SearchCharFlags.WordBoundary, searchCharFlags[3]);
}
private static decimal SimpleScore(int[] searchCharPositions, SearchCharFlags[] searchCharFlags)
{
double maxPerCharScore = 1.0/(double)searchCharPositions.Length;
double totalScore = 0;
foreach (SearchCharFlags flags in searchCharFlags) {
if ((flags & SearchCharFlags.WordBoundary) != 0 ||
(flags & SearchCharFlags.SurroundedChar) != 0) {
//This character is a word boundary, or is surrounded by matching search chars on both sides
totalScore += maxPerCharScore;
} else if ((flags & SearchCharFlags.PreceedingChar) != 0 ||
(flags & SearchCharFlags.SucceedingChar) != 0) {
//Preceeds or succeeds a matching char; that's only a half score
totalScore += maxPerCharScore / 2.0;
}
}
return (decimal)totalScore;
}
public static void MarkWordBoundaries(string title, string searchString, int[] searchCharPositions, out SearchCharFlags[] searchCharFlags)
{
// Check for search letters at the start of words, at positions equal to or earlier than
// the right-most positions found above
int[] wordStartPositions;
Char[] wordStartCharacters;
searchCharFlags = new SearchCharFlags[searchString.Length];
FindWordStarts(title, out wordStartPositions, out wordStartCharacters);
List<Char> wordStartCharsList = new List<char>(wordStartCharacters);
int wordIdx = 0;
for (int idx = 0; idx < searchCharPositions.Length; idx++)
{
int val = searchCharPositions[idx];
Char searchChar = searchString[idx];
// Does the character at this index start a word?
int tempIdx = wordStartCharsList.IndexOf(searchChar, wordIdx);
if (tempIdx != -1 &&
wordStartPositions[tempIdx] <= val)
{
// A word starting with this character is present in the string on or before
// the right-most occurence of this char.
searchCharFlags[idx] = SearchCharFlags.WordBoundary;
wordIdx = tempIdx + 1;
if (wordIdx == wordStartCharacters.Length)
{
// No more words
break;
}
}
else
{
// No word starting with this character. pick up the word-start search for subsequent
// characters, after the nearest occurence of this character.
int nearestCharIdx = title.IndexOf(searchString[idx], wordStartPositions[wordIdx]);
if (nearestCharIdx == -1)
{
// This character isn't present past the current word, which means no further
// characters will be either; abort the search
break;
}
// Find the first word start index AFTER this char
wordIdx = -1;
for (int wordStartPosIdx = 0;
wordStartPosIdx < wordStartPositions.Length;
wordStartPosIdx++)
{
int wordStartPos = wordStartPositions[wordStartPosIdx];
if (wordStartPos > nearestCharIdx)
{
wordIdx = wordStartPosIdx;
}
}
if (wordIdx == -1)
{
// No more word starts; that's the last of the search terms that align on
// word boundaries
break;
}
}
}
}
private static void FindSearchCharsInTitle(string title, string searchString, out int[] searchCharPositions, out SearchCharFlags[] searchCharFlags)
{
//For each search character, find its right-most occurrence in title while preserving the search character order
searchCharPositions = FindRightmostCharPositions(title, searchString);
MarkWordBoundaries(title, searchString, searchCharPositions, out searchCharFlags);
}
