internal static bool TryParse <T>(BoundDirection lowerDirection
, T lowerValue
, T upperValue
, BoundDirection upperDirection
, out Interval <T> result)
{
Bound <T> lowerBound, upperBound;
if (Bound.TryParse(BoundType.Lower, lowerDirection, lowerValue, out lowerBound) &&
Bound.TryParse(BoundType.Upper, upperDirection, upperValue, out upperBound))
{
return(Interval.TryParse(lowerBound, upperBound, out result));
}
result = default(Interval <T>);
return(false);
}
/// <summary>
/// Initializes a new instance of the <see cref="Interval<T>"/> class.
/// </summary>
/// <param name="lowerBound">The lower bound.</param>
/// <param name="upperBound">The upper bound.</param>
protected internal Interval(Bound <T> lowerBound
, Bound <T> upperBound)
{
if (lowerBound == null || upperBound == null)
{
throw new ArgumentNullException("lowerBound or upperBound");
}
if (lowerBound > upperBound)
{
throw new ArgumentException("The lower bound must be lower than or equal the upper bound.");
}
if (object.Equals(lowerBound.Value, upperBound.Value) &&
!object.Equals(lowerBound.Direction, upperBound.Direction) &&
!Bound.IsInfinity(lowerBound.Value))
{
throw new ArgumentException("Singleton or empty interval must define the same boundary direction.");
}
LowerBound = lowerBound;
UpperBound = upperBound;
}
internal static bool TryParse <T>(Bound <T> lowerBound
, Bound <T> upperBound
, out Interval <T> result)
{
result = default(Interval <T>);
if (lowerBound == null ||
upperBound == null ||
lowerBound > upperBound)
{
return(false);
}
if (object.Equals(lowerBound.Value, upperBound.Value) &&
!object.Equals(lowerBound.Direction, upperBound.Direction) &&
!Bound.IsInfinity(lowerBound.Value))
{
return(false);
}
result = new Interval <T>(lowerBound, upperBound);
return(true);
}
/// <summary>
/// Initializes a new instance of the <see cref="Period"/> class.
/// </summary>
/// <param name="lowerBound">The lower bound.</param>
/// <param name="upperBound">The upper bound.</param>
public Period(Bound <DateTimeOffset?> lowerBound, Bound <DateTimeOffset?> upperBound)
: base(lowerBound, upperBound)
{
}
internal int UnionCompareTo(Bound <T> other)
{
//perform value comparaison
var vCompare = ((Type == BoundType.Upper && Bound.IsInfinity(Value)) || (other.Type == BoundType.Upper && Bound.IsInfinity(other.Value)))
? Comparer <T> .Default.Compare(other.Value, Value)
: Comparer <T> .Default.Compare(Value, other.Value);
return((vCompare != 0)
? vCompare
: (object.Equals(Direction, BoundDirection.Closed) || object.Equals(other.Direction, BoundDirection.Closed))
? 0
: -1);
}
/// <summary>
/// Compares this instance to a specified <see cref="Bound<T>"/> and returns an indication of their relative values.
/// </summary>
/// <param name="other">A <see cref="Bound<T>"/> to compare to this instance.</param>
/// <returns>
/// A signed number indicating the relative values of this instance and the <paramref name="other"/>.
/// <list type="table">
/// <listheader>
/// <term>Value Type</term>
/// <description>Condition</description>
/// </listheader>
/// <item>
/// <term>Less than zero</term>
/// <description>This instance is less than the <paramref name="other"/>.</description>
/// </item>
/// <item>
/// <term>Zero</term>
/// <description>This instance is equal to the <paramref name="other"/>.</description>
/// </item>
/// <item>
/// <term>Greater than zero</term>
/// <description>This instance is greater than the <paramref name="other"/>.</description>
/// </item>
///</list>
/// </returns>
/// <exception cref="ArgumentNullException"><paramref name="other"/> is null.</exception>
public int CompareTo(Bound <T> other)
{
if (other == null)
{
throw new ArgumentNullException("other");
}
//perform value comparaison
var vCompare = ((Type == BoundType.Upper && Bound.IsInfinity(Value)) || (other.Type == BoundType.Upper && Bound.IsInfinity(other.Value)))
? Comparer <T> .Default.Compare(other.Value, Value)
: Comparer <T> .Default.Compare(Value, other.Value);
//consider value comparaison
if (vCompare != 0)
{
return(vCompare);
}
else
{
//perform type comparaison
var tCompare = Type.CompareTo(other.Type);
if (tCompare != 0)
{
return(tCompare);
}
else
{
//perform direction comparaison
return((Type == BoundType.Upper)
? Direction.CompareTo(other.Direction)
: other.Direction.CompareTo(Direction));
}
}
}
/// <summary>
/// Overrides the default bound values of <see cref="Interval<T>"/>.
/// </summary>
/// <param name="lowestValue">The lowest value.</param>
/// <param name="upmostValue">The upmost value.</param>
public static void OverrideBounds(T lowestValue, T upmostValue)
{
Bound <T> .OverrideBounds(lowestValue, upmostValue);
}
private static IntervalCollection <T> HighUnionOf <T>(Interval <T> a, Interval <T> b)
{
if (Interval.IsNullOrEmpty(a))
{
return(new IntervalCollection <T>(b));
}
if (Interval.IsNullOrEmpty(b))
{
return(new IntervalCollection <T>(a));
}
var lowestBound = Bound.Min(a.LowerBound, b.LowerBound);
var upmostValue = Bound.Max(a.UpperBound, b.UpperBound);
var lowerBound = default(Bound <T>);
var upperBound = default(Bound <T>);
// a
//-------------
// b
// ---------
if (object.Equals(lowestBound, a.LowerBound) &&
object.Equals(upmostValue, a.UpperBound))
{
lowerBound = new Bound <T>(BoundType.Lower
, object.Equals(a.LowerBound.Value, b.LowerBound.Value)
? Bound.Max(a.LowerBound.Direction, b.LowerBound.Direction)
: a.LowerBound.Direction
, a.LowerBound.Value);
upperBound = new Bound <T>(BoundType.Upper
, object.Equals(a.UpperBound.Value, b.UpperBound.Value)
? Bound.Max(a.UpperBound.Direction, b.UpperBound.Direction)
: a.UpperBound.Direction
, a.UpperBound.Value);
}
// a
// ---------
// b
//-------------
else if (object.Equals(lowestBound, b.LowerBound) &&
object.Equals(upmostValue, b.UpperBound))
{
lowerBound = new Bound <T>(BoundType.Lower
, object.Equals(a.LowerBound.Value, b.LowerBound.Value)
? Bound.Max(a.LowerBound.Direction, b.LowerBound.Direction)
: b.LowerBound.Direction
, b.LowerBound.Value);
upperBound = new Bound <T>(BoundType.Upper
, object.Equals(a.UpperBound.Value, b.UpperBound.Value)
? Bound.Max(a.UpperBound.Direction, b.UpperBound.Direction)
: b.UpperBound.Direction
, b.UpperBound.Value);
}
// a
//---------
// b
// -------------
else if (object.Equals(lowestBound, a.LowerBound) &&
object.Equals(upmostValue, b.UpperBound) &&
a.UpperBound.UnionCompareTo(b.LowerBound) >= 0)
{
lowerBound = new Bound <T>(BoundType.Lower
, object.Equals(a.LowerBound.Value, b.LowerBound.Value)
? Bound.Max(a.LowerBound.Direction, b.LowerBound.Direction)
: a.LowerBound.Direction
, a.LowerBound.Value);
upperBound = new Bound <T>(BoundType.Upper
, object.Equals(a.UpperBound.Value, b.UpperBound.Value)
? Bound.Max(a.UpperBound.Direction, b.UpperBound.Direction)
: b.UpperBound.Direction
, b.UpperBound.Value);
}
// a
// -------------
// b
//---------
else if (object.Equals(lowestBound, b.LowerBound) &&
object.Equals(upmostValue, a.UpperBound) &&
b.UpperBound.UnionCompareTo(a.LowerBound) >= 0)
{
lowerBound = new Bound <T>(BoundType.Lower
, object.Equals(a.LowerBound.Value, b.LowerBound.Value)
? Bound.Max(a.LowerBound.Direction, b.LowerBound.Direction)
: b.LowerBound.Direction
, b.LowerBound.Value);
upperBound = new Bound <T>(BoundType.Upper
, object.Equals(a.UpperBound.Value, b.UpperBound.Value)
? Bound.Max(a.UpperBound.Direction, b.UpperBound.Direction)
: a.UpperBound.Direction
, a.UpperBound.Value);
}
else
{
return(new IntervalCollection <T>(a, b));
}
Interval <T> result;
return(TryParse(lowerBound, upperBound, out result)
? new IntervalCollection <T>(result)
: new IntervalCollection <T>(a, b));
}
/// <summary>
/// Determines the intersection of two intervals.
/// </summary>
/// <typeparam name="T">The value type of the intervals.</typeparam>
/// <param name="a">The first interval.</param>
/// <param name="b">The second interval.</param>
/// <returns>An <see cref="Interval<T>"/> that contains all elements of <paramref name="a"/>
/// that also belong to <paramref name="b"/> (or equivalently, all elements of <paramref name="b"/>
/// that also belong to <paramref name="a"/>), but no other elements.</returns>
/// <seealso href="http://en.wikipedia.org/wiki/Intersection_(set_theory)">Intersection (set theory)</seealso>
private static Interval <T> IntersectionOf <T>(Interval <T> a, Interval <T> b)
{
if (Interval.IsNullOrEmpty(a))
{
return(a);
}
if (Interval.IsNullOrEmpty(b))
{
return(b);
}
var lowestBound = Bound.Min(a.LowerBound, b.LowerBound);
var upmostValue = Bound.Max(a.UpperBound, b.UpperBound);
var lowerBound = default(Bound <T>);
var upperBound = default(Bound <T>);
// a
//-------------
// b
// ---------
if (object.Equals(lowestBound, a.LowerBound) &&
object.Equals(upmostValue, a.UpperBound))
{
lowerBound = new Bound <T>(BoundType.Lower
, object.Equals(a.LowerBound.Value, b.LowerBound.Value)
? Bound.Min(a.LowerBound.Direction, b.LowerBound.Direction)
: b.LowerBound.Direction
, b.LowerBound.Value);
upperBound = new Bound <T>(BoundType.Upper
, object.Equals(a.UpperBound.Value, b.UpperBound.Value)
? Bound.Min(a.UpperBound.Direction, b.UpperBound.Direction)
: b.UpperBound.Direction
, b.UpperBound.Value);
}
// a
// ---------
// b
//-------------
else if (object.Equals(lowestBound, b.LowerBound) &&
object.Equals(upmostValue, b.UpperBound))
{
lowerBound = new Bound <T>(BoundType.Lower
, object.Equals(a.LowerBound.Value, b.LowerBound.Value)
? Bound.Min(a.LowerBound.Direction, b.LowerBound.Direction)
: a.LowerBound.Direction
, a.LowerBound.Value);
upperBound = new Bound <T>(BoundType.Upper
, object.Equals(a.UpperBound.Value, b.UpperBound.Value)
? Bound.Min(a.UpperBound.Direction, b.UpperBound.Direction)
: a.UpperBound.Direction
, a.UpperBound.Value);
}
// a
//---------
// b
// -------------
else if (object.Equals(lowestBound, a.LowerBound) &&
object.Equals(upmostValue, b.UpperBound))
{
lowerBound = new Bound <T>(BoundType.Lower
, object.Equals(a.LowerBound.Value, b.LowerBound.Value)
? Bound.Min(a.LowerBound.Direction, b.LowerBound.Direction)
: b.LowerBound.Direction
, b.LowerBound.Value);
upperBound = new Bound <T>(BoundType.Upper
, object.Equals(a.UpperBound.Value, b.UpperBound.Value)
? Bound.Min(a.UpperBound.Direction, b.UpperBound.Direction)
: a.UpperBound.Direction
, a.UpperBound.Value);
}
// a
// -------------
// b
//---------
else if (object.Equals(lowestBound, b.LowerBound) &&
object.Equals(upmostValue, a.UpperBound))
{
lowerBound = new Bound <T>(BoundType.Lower
, object.Equals(a.LowerBound.Value, b.LowerBound.Value)
? Bound.Min(a.LowerBound.Direction, b.LowerBound.Direction)
: a.LowerBound.Direction
, a.LowerBound.Value);
upperBound = new Bound <T>(BoundType.Upper
, object.Equals(a.UpperBound.Value, b.UpperBound.Value)
? Bound.Min(a.UpperBound.Direction, b.UpperBound.Direction)
: b.UpperBound.Direction
, b.UpperBound.Value);
}
else
{
return(Interval.Empty <T>());
}
Interval <T> result;
return(TryParse(lowerBound, upperBound, out result)
? result
: Interval.Empty <T>());
}
