/// <summary>
/// Creates a new <see cref="BclDateTimeZone" /> from a <see cref="TimeZoneInfo"/> from the Base Class Library.
/// </summary>
/// <param name="bclZone">The original time zone to take information from.</param>
/// <returns>A <see cref="BclDateTimeZone"/> wrapping the given <c>TimeZoneInfo</c>.</returns>
public static BclDateTimeZone FromTimeZoneInfo(TimeZoneInfo bclZone)
{
Preconditions.CheckNotNull(bclZone, nameof(bclZone));
Offset standardOffset = bclZone.BaseUtcOffset.ToOffset();
var rules = bclZone.GetAdjustmentRules();
if (!bclZone.SupportsDaylightSavingTime || rules.Length == 0)
{
var fixedInterval = new ZoneInterval(bclZone.StandardName, Instant.BeforeMinValue, Instant.AfterMaxValue, standardOffset, Offset.Zero);
return(new BclDateTimeZone(bclZone, standardOffset, standardOffset, new SingleZoneIntervalMap(fixedInterval)));
}
int windowsRules = rules.Count(IsWindowsRule);
var ruleConverter = AreWindowsStyleRules(rules)
? rule => BclAdjustmentRule.FromWindowsAdjustmentRule(bclZone, rule)
: (Converter <TimeZoneInfo.AdjustmentRule, BclAdjustmentRule>)(rule => BclAdjustmentRule.FromUnixAdjustmentRule(bclZone, rule));
BclAdjustmentRule[] convertedRules = Array.ConvertAll(rules, ruleConverter);
Offset minRuleOffset = convertedRules.Aggregate(Offset.MaxValue, (min, rule) => Offset.Min(min, rule.Savings + rule.StandardOffset));
Offset maxRuleOffset = convertedRules.Aggregate(Offset.MinValue, (min, rule) => Offset.Max(min, rule.Savings + rule.StandardOffset));
IZoneIntervalMap uncachedMap = BuildMap(convertedRules, standardOffset, bclZone.StandardName);
IZoneIntervalMap cachedMap = CachingZoneIntervalMap.CacheMap(uncachedMap);
return(new BclDateTimeZone(bclZone, Offset.Min(standardOffset, minRuleOffset), Offset.Max(standardOffset, maxRuleOffset), cachedMap));
}
/// <summary>
/// Creates a new <see cref="BclDateTimeZone" /> from a <see cref="TimeZoneInfo"/> from the Base Class Library.
/// </summary>
/// <param name="bclZone">The original time zone to take information from.</param>
/// <returns>A <see cref="BclDateTimeZone"/> wrapping the given <c>TimeZoneInfo</c>.</returns>
public static BclDateTimeZone FromTimeZoneInfo(TimeZoneInfo bclZone)
{
Preconditions.CheckNotNull(bclZone, nameof(bclZone));
Offset standardOffset = bclZone.BaseUtcOffset.ToOffset();
var rules = bclZone.GetAdjustmentRules();
if (!bclZone.SupportsDaylightSavingTime || rules.Length == 0)
{
var fixedInterval = new ZoneInterval(bclZone.StandardName, Instant.BeforeMinValue, Instant.AfterMaxValue, standardOffset, Offset.Zero);
return(new BclDateTimeZone(bclZone, new SingleZoneIntervalMap(fixedInterval)));
}
BclAdjustmentRule[] convertedRules;
if (AreWindowsStyleRules(rules))
{
convertedRules = Array.ConvertAll(rules, rule => BclAdjustmentRule.FromWindowsAdjustmentRule(bclZone, rule));
}
else
{
convertedRules = Array.ConvertAll(rules, rule => BclAdjustmentRule.FromUnixAdjustmentRule(bclZone, rule));
FixUnixTransitions(convertedRules);
}
IZoneIntervalMap uncachedMap = BuildMap(convertedRules, standardOffset, bclZone.StandardName);
IZoneIntervalMap cachedMap = CachingZoneIntervalMap.CacheMap(uncachedMap);
return(new BclDateTimeZone(bclZone, cachedMap));
}
/// <summary>
/// Returns a cached time zone for the given time zone.
/// </summary>
/// <remarks>
/// If the time zone is already cached or it is fixed then it is returned unchanged.
/// </remarks>
/// <param name="timeZone">The time zone to cache.</param>
/// <returns>The cached time zone.</returns>
internal static DateTimeZone ForZone(DateTimeZone timeZone)
{
Preconditions.CheckNotNull(timeZone, nameof(timeZone));
if (timeZone is CachedDateTimeZone || timeZone.IsFixed)
{
return(timeZone);
}
return(new CachedDateTimeZone(timeZone, CachingZoneIntervalMap.CacheMap(timeZone)));
}
/// <summary>
/// Creates a new <see cref="BclDateTimeZone" /> from a <see cref="TimeZoneInfo"/> from the Base Class Library.
/// </summary>
/// <param name="bclZone">The original time zone to take information from.</param>
/// <returns>A <see cref="BclDateTimeZone"/> wrapping the given <c>TimeZoneInfo</c>.</returns>
[NotNull] public static BclDateTimeZone FromTimeZoneInfo([NotNull] TimeZoneInfo bclZone)
{
Preconditions.CheckNotNull(bclZone, nameof(bclZone));
Offset standardOffset = bclZone.BaseUtcOffset.ToOffset();
var rules = bclZone.GetAdjustmentRules();
if (!bclZone.SupportsDaylightSavingTime || rules.Length == 0)
{
var fixedInterval = new ZoneInterval(bclZone.StandardName, Instant.BeforeMinValue, Instant.AfterMaxValue, standardOffset, Offset.Zero);
return(new BclDateTimeZone(bclZone, standardOffset, standardOffset, new SingleZoneIntervalMap(fixedInterval)));
}
BclAdjustmentRule[] convertedRules = Array.ConvertAll(rules, rule => new BclAdjustmentRule(bclZone, rule));
Offset minRuleOffset = convertedRules.Aggregate(Offset.MaxValue, (min, rule) => Offset.Min(min, rule.Savings + rule.StandardOffset));
Offset maxRuleOffset = convertedRules.Aggregate(Offset.MinValue, (min, rule) => Offset.Max(min, rule.Savings + rule.StandardOffset));
IZoneIntervalMap uncachedMap = BuildMap(convertedRules, standardOffset, bclZone.StandardName);
IZoneIntervalMap cachedMap = CachingZoneIntervalMap.CacheMap(uncachedMap, CachingZoneIntervalMap.CacheType.Hashtable);
return(new BclDateTimeZone(bclZone, Offset.Min(standardOffset, minRuleOffset), Offset.Max(standardOffset, maxRuleOffset), cachedMap));
}
/// <summary>
/// Creates a new <see cref="BclDateTimeZone" /> from a <see cref="TimeZoneInfo"/> from the Base Class Library.
/// </summary>
/// <param name="bclZone">The original time zone to take information from.</param>
/// <returns>A <see cref="BclDateTimeZone"/> wrapping the given <c>TimeZoneInfo</c>.</returns>
public static BclDateTimeZone FromTimeZoneInfo([NotNull] TimeZoneInfo bclZone)
{
Preconditions.CheckNotNull(bclZone, "bclZone");
Offset standardOffset = Offset.FromTimeSpan(bclZone.BaseUtcOffset);
Offset minSavings = Offset.Zero; // Just in case we have negative savings!
Offset maxSavings = Offset.Zero;
var rules = bclZone.GetAdjustmentRules();
if (!bclZone.SupportsDaylightSavingTime || rules.Length == 0)
{
var fixedInterval = new ZoneInterval(bclZone.StandardName, Instant.MinValue, Instant.MaxValue, standardOffset, Offset.Zero);
return(new BclDateTimeZone(bclZone, standardOffset, standardOffset, new FixedZoneIntervalMap(fixedInterval)));
}
var adjustmentIntervals = new List <AdjustmentInterval>();
var headInterval = ComputeHeadInterval(bclZone, rules[0]);
Instant previousEnd = headInterval != null ? headInterval.End : Instant.MinValue;
// TODO(Post-V1): Tidy this up. All of this is horrible.
for (int i = 0; i < rules.Length; i++)
{
var rule = rules[i];
ZoneRecurrence standard, daylight;
GetRecurrences(bclZone, rule, out standard, out daylight);
minSavings = Offset.Min(minSavings, daylight.Savings);
maxSavings = Offset.Max(maxSavings, daylight.Savings);
// Find the last valid transition by working back from the end of time. It's safe to unconditionally
// take the value here, as there must *be* some recurrences.
var lastStandard = standard.PreviousOrFail(LastValidTick, standardOffset, daylight.Savings);
var lastDaylight = daylight.PreviousOrFail(LastValidTick, standardOffset, Offset.Zero);
bool standardIsLater = lastStandard.Instant > lastDaylight.Instant;
Transition lastTransition = standardIsLater ? lastStandard : lastDaylight;
Offset seamSavings = lastTransition.NewOffset - standardOffset;
string seamName = standardIsLater ? bclZone.StandardName : bclZone.DaylightName;
Instant nextStart;
Instant ruleEnd = GetRuleEnd(rule, lastTransition);
// Handle the final rule, which may or may not to extend to the end of time. If it doesn't,
// we transition to standard time at the end of the rule.
if (i == rules.Length - 1)
{
// If the final transition was to standard time, we can just treat the seam as going on forever.
nextStart = standardIsLater ? Instant.MaxValue : ruleEnd;
var seam = new ZoneInterval(seamName, lastTransition.Instant, nextStart, lastTransition.NewOffset, seamSavings);
var adjustmentZone = new DaylightSavingsDateTimeZone("ignored", standardOffset, standard.ToInfinity(), daylight.ToInfinity());
adjustmentIntervals.Add(new AdjustmentInterval(previousEnd, adjustmentZone, seam));
previousEnd = nextStart;
}
else
{
// Handle one rule going into another. This is the cause of much pain, as there are several options:
// 1) Going into a "normal" rule with two transitions per year.
// 2) Going into a "single transition" rule, signified by a transition "into" the current offset
// right at the start of the year. This is treated as if the on-the-edge transition doesn't exist.
//
// Additionally, there's the possibility that the offset at the start of the next rule (i.e. the
// one before the first transition) isn't the same as the offset at the end of end of the current rule
// (i.e. lastTransition.NewOffset). This only occurs for Namibia time as far as we've seen, but in that
// case we create a seam which only goes until the end of this rule, then an extra zone interval for
// the time between the start of the rule and the first transition, then we're as normal, starting at
// the first transition. See bug 115 for a bit more information.
var nextRule = rules[i + 1];
ZoneRecurrence nextStandard, nextDaylight;
GetRecurrences(bclZone, nextRule, out nextStandard, out nextDaylight);
// By using the seam's savings for *both* checks, we can detect "daylight to daylight" and
// "standard to standard" transitions as happening at the very start of the rule.
var firstStandard = nextStandard.NextOrFail(lastTransition.Instant, standardOffset, seamSavings);
var firstDaylight = nextDaylight.NextOrFail(lastTransition.Instant, standardOffset, seamSavings);
// Ignore any "right at the start of the rule" transitions.
var firstStandardInstant = firstStandard.Instant == ruleEnd ? Instant.MaxValue : firstStandard.Instant;
var firstDaylightInstant = firstDaylight.Instant == ruleEnd ? Instant.MaxValue : firstDaylight.Instant;
bool firstStandardIsEarlier = firstStandardInstant < firstDaylightInstant;
var firstTransition = firstStandardIsEarlier ? firstStandard : firstDaylight;
nextStart = firstTransition.Instant;
var seamEnd = nextStart;
AdjustmentInterval startOfRuleExtraSeam = null;
Offset previousOffset = firstStandardIsEarlier ? firstDaylight.NewOffset : firstStandard.NewOffset;
if (previousOffset != lastTransition.NewOffset)
{
seamEnd = ruleEnd;
// Recalculate the *real* transition, as we're now going from a different wall offset...
var firstRule = firstStandardIsEarlier ? nextStandard : nextDaylight;
nextStart = firstRule.NextOrFail(ruleEnd, standardOffset, previousOffset - standardOffset).Instant;
var extraSeam = new ZoneInterval(firstStandardIsEarlier ? bclZone.DaylightName : bclZone.StandardName,
ruleEnd, nextStart, previousOffset, previousOffset - standardOffset);
// The extra adjustment interval is really just a single zone interval; we'll never need the DaylightSavingsDateTimeZone part.
startOfRuleExtraSeam = new AdjustmentInterval(extraSeam.Start, null, extraSeam);
}
var seam = new ZoneInterval(seamName, lastTransition.Instant, seamEnd, lastTransition.NewOffset, seamSavings);
var adjustmentZone = new DaylightSavingsDateTimeZone("ignored", standardOffset, standard.ToInfinity(), daylight.ToInfinity());
adjustmentIntervals.Add(new AdjustmentInterval(previousEnd, adjustmentZone, seam));
if (startOfRuleExtraSeam != null)
{
adjustmentIntervals.Add(startOfRuleExtraSeam);
}
previousEnd = nextStart;
}
}
ZoneInterval tailInterval = previousEnd == Instant.MaxValue ? null
: new ZoneInterval(bclZone.StandardName, previousEnd, Instant.MaxValue, standardOffset, Offset.Zero);
IZoneIntervalMap uncachedMap = new BclZoneIntervalMap(adjustmentIntervals, headInterval, tailInterval);
IZoneIntervalMap cachedMap = CachingZoneIntervalMap.CacheMap(uncachedMap, CachingZoneIntervalMap.CacheType.Hashtable);
return(new BclDateTimeZone(bclZone, standardOffset + minSavings, standardOffset + maxSavings, cachedMap));
}
