/// <summary>
/// Extends the input at both ends with the given parameter.
/// </summary>
/// <param name="input">The input to extend.</param>
/// <param name="expand">A copy of the extended input.</param>
/// <returns></returns>
public static IEnumerable <TimeWindow> Extend(this IEnumerable <TimeWindow> input, TimeSpan expand)
{
TimeWindow previous = null;
foreach (var tw in input)
{
var extended = tw.Extend(expand);
if (previous == null)
{
previous = extended;
}
else if (extended != null && extended.From <= previous.To)
{
previous.To = extended.To;
}
else
{
// ReSharper disable once ConditionIsAlwaysTrueOrFalse
if (previous != null)
{
yield return(previous);
}
previous = extended;
}
}
if (previous != null)
{
yield return(previous);
}
}
/// <summary>
/// Creates an intersect of this instance and the time window parameter.
/// </summary>
/// <param name="other">The time window parameter to insersect with.</param>
/// <returns>The intersection of the time windows.</returns>
public TimeWindow Intersect(TimeWindow other)
{
return(Validate(new TimeWindow
{
From = this.From > other.From ? this.From : other.From,
To = this.To < other.To ? this.To : other.To
}));
}
/// <summary>
/// Returns the input time window validated.
/// </summary>
/// <param name="input">The input tiem window.</param>
/// <returns>The validated input or null if the input was invalid.</returns>
private static TimeWindow Validate(TimeWindow input)
{
if (input.From < input.To)
{
return(input);
}
else
{
return(null);
}
}
