public ReadOnlyTextRangeCollection(TextRangeCollection <T> collection)
{
_collection = collection;
}
/// <summary>
/// Compares two collections and calculates 'changed' range. In case this collection
/// or comparand are empty, uses lowerBound and upperBound values as range
/// delimiters. Typically lowerBound is 0 and upperBound is lentgh of the file.
/// </summary>
/// <param name="otherCollection">Collection to compare to</param>
public virtual ITextRange RangeDifference(IEnumerable <ITextRange> otherCollection, int lowerBound, int upperBound)
{
if (otherCollection == null)
{
return(TextRange.FromBounds(lowerBound, upperBound));
}
var other = new TextRangeCollection <ITextRange>(otherCollection);
if (this.Count == 0 && other.Count == 0)
{
return(TextRange.EmptyRange);
}
if (this.Count == 0)
{
return(TextRange.FromBounds(lowerBound, upperBound));
}
if (other.Count == 0)
{
return(TextRange.FromBounds(lowerBound, upperBound));
}
int minCount = Math.Min(this.Count, other.Count);
int start = 0;
int end = 0;
int i, j;
for (i = 0; i < minCount; i++)
{
start = Math.Min(this[i].Start, other[i].Start);
if (this[i].Start != other[i].Start || this[i].Length != other[i].Length)
{
break;
}
}
if (i == minCount)
{
if (this.Count == other.Count)
{
return(TextRange.EmptyRange);
}
if (this.Count > other.Count)
{
return(TextRange.FromBounds(Math.Min(upperBound, other[minCount - 1].Start), upperBound));
}
else
{
return(TextRange.FromBounds(Math.Min(this[minCount - 1].Start, upperBound), upperBound));
}
}
for (i = this.Count - 1, j = other.Count - 1; i >= 0 && j >= 0; i--, j--)
{
end = Math.Max(this[i].End, other[j].End);
if (this[i].Start != other[j].Start || this[i].Length != other[j].Length)
{
break;
}
}
if (start < end)
{
return(TextRange.FromBounds(start, end));
}
return(TextRange.FromBounds(lowerBound, upperBound));
}