/// <summary>
/// Builds a time zone with the given ID from a sequence of rule sets.
/// </summary>
internal static DateTimeZone Build(string id, IList <ZoneRuleSet> ruleSets)
{
Preconditions.CheckArgument(ruleSets.Count > 0, nameof(ruleSets), "Cannot create a time zone without any Zone entries");
var builder = new DateTimeZoneBuilder();
return(builder.BuildZone(id, ruleSets));
}
/// <summary>
/// Adds a recurring savings rule to the time zone builder.
/// </summary>
/// <param name="builder">The <see cref="DateTimeZoneBuilder" /> to add to.</param>
/// <param name="nameFormat">The name format pattern.</param>
/// <param name="ruleSet">The <see cref="ZoneRecurrenceCollection" /> describing the recurring savings.</param>
private static void AddRecurring(DateTimeZoneBuilder builder, String nameFormat, IEnumerable <ZoneRule> ruleSet)
{
foreach (var rule in ruleSet)
{
string name = rule.FormatName(nameFormat);
builder.AddRecurringSavings(rule.Recurrence.WithName(name));
}
}
/// <summary>
/// Returns a newly created <see cref="DateTimeZone" /> built from the given time zone data.
/// </summary>
/// <param name="zoneList">The time zone definition parts to add.</param>
private DateTimeZone CreateTimeZone(ZoneList zoneList)
{
var builder = new DateTimeZoneBuilder();
foreach (Zone zone in zoneList)
{
builder.SetStandardOffset(zone.Offset);
if (zone.Rules == null)
{
builder.SetFixedSavings(zone.Format, Offset.Zero);
}
else
{
IList <ZoneRule> ruleSet;
if (Rules.TryGetValue(zone.Rules, out ruleSet))
{
AddRecurring(builder, zone.Format, ruleSet);
}
else
{
try
{
// Check if Rules actually just refers to a savings.
var savings = ParserHelper.ParseOffset(zone.Rules);
builder.SetFixedSavings(zone.Format, savings);
}
catch (FormatException)
{
throw new ArgumentException(
String.Format("Daylight savings rule name '{0}' for zone {1} is neither a known ruleset nor a fixed offset",
zone.Rules, zone.Name));
}
}
}
if (zone.UntilYear == Int32.MaxValue)
{
break;
}
builder.AddCutover(zone.UntilYear, zone.UntilYearOffset);
}
return(builder.ToDateTimeZone(zoneList.Name));
}
/// <summary>
/// Returns a newly created <see cref="DateTimeZone" /> built from the given time zone data.
/// </summary>
/// <param name="zoneList">The time zone definition parts to add.</param>
private DateTimeZone CreateTimeZone(string id, IList <ZoneLine> zoneList)
{
var ruleSets = zoneList.Select(zone => zone.ResolveRules(Rules)).ToList();
return(DateTimeZoneBuilder.Build(id, ruleSets));
}