private static int NormalizeIndex <T>(int index, List <T> collection, EBias bias)
{
if (index > 0)
{
return(index);
}
index = ~index;
if (index == collection.Count)
{
return(-1);
}
return(bias == EBias.GREATEST_LOWER_BOUND ? index - 1 : index);
}
/**
* Find the mapping that best matches the hypothetical "needle" mapping that
* we are searching for in the given "haystack" of mappings.
*/
protected int FindMapping(
MappingItemIndexed needle,
List <MappingItemIndexed> aMappings,
Func <MappingItemIndexed, int?> line,
Func <MappingItemIndexed, int?> column,
Func <MappingItemIndexed, MappingItemIndexed, int> aComparator,
EBias aBias)
{
// To return the position we are searching for, we must first find the
// mapping for the given position and then return the opposite position it
// points to. Because the mappings are sorted, we can use binary search to
// find the best mapping.
if (line(needle) <= 0)
{
throw new ArgumentException($"Line must be greater than or equal to 1, got {line(needle)}");
}
if (column(needle) < 0)
{
throw new ArgumentException($"Column must be greater than or equal to 0, got {column(needle)}");
}
return(BinarySearch.Search <MappingItemIndexed>(needle, aMappings, aComparator, aBias));
}
public static int Search <T>(T term, List <T> collection, Func <T, T, int> comparer, EBias bias)
{
var index = collection.BinarySearch(term, new Comaprer <T>(comparer));
return(NormalizeIndex(index, collection, bias));
}
public static int Search <TTerm, T>(TTerm term, List <T> collection, Func <TTerm, T, int> comparer, EBias bias) where T : new()
{
var marker = new T();
var index = collection.BinarySearch(marker, new Comaprer <TTerm, T>(term, comparer, marker));
return(NormalizeIndex(index, collection, bias));
}
