/// <summary>
/// Obtient le standard offset applicable à une règle
/// </summary>
/// <param name="year"></param>
/// <param name="rules"></param>
/// <param name="rule"></param>
/// <param name="zoneDate"></param>
/// <param name="gmtOffset"></param>
/// <returns></returns>
/// <remarks>Cette fonction compare des règles définies, comme un changement d'heure ne se
/// produit pas en même temps qu'un autre on peut appliquer le stdoff entre règles sans
/// se soucier de point recouvrant.
/// </remarks>
private static TimeSpan GetLastSaveOffset(int year, List<Rule> rules, Rule rule, TzTimeZoneRuleDate zoneDate, TimeSpan gmtOffset)
{
int bestyear = -1;
TimeSpan range = TimeSpan.MaxValue;
TimeSpan stdoff = zoneDate.StandardOffset;
for (int index = rules.Count - 1; index >= 0; index--) {
if (rules[index] == rule) continue;
if (rules[index].LowerYear > year || rules[index].HighYear < bestyear) {
continue;
}
int yref = (rules[index].HighYear > year) ? year : rules[index].HighYear;
if (yref == year && rules[index].AtKind == rule.AtKind &&
(rules[index].Month > rule.Month || (rules[index].Month == rule.Month && rules[index].Day.DayWork == DayWorkKind.Dom && rule.Day.DayWork == DayWorkKind.Dom && rules[index].Day.DayOfMonth > rule.Day.DayOfMonth))) {
if (yref > rules[index].LowerYear)
yref--;
else
continue;
}
for (; yref >= rules[index].LowerYear; yref--) {
if (!TzUtilities.IsYearType(yref, rules[index].YearType)) continue;
DateTime precedent;
DateTime current;
// On compare la date avec la date limite de zone
if (rules[index].AtKind == TimeKind.LocalWallTime) {
precedent = TzUtilities.GetDateTime(rules[index], yref, gmtOffset, TimeSpan.Zero, DateTimeKind.Local);
if (zoneDate.ToLocalTime() > precedent)
break;
// On exprime la date courante de la règle à vérifier en local
current = TzUtilities.GetDateTime(rule, year, gmtOffset, rules[index].StandardOffset, DateTimeKind.Local);
}
else {
precedent = TzUtilities.GetDateTime(rules[index], yref, gmtOffset, TimeSpan.Zero, DateTimeKind.Utc);
if (zoneDate.UtcDate > precedent)
break;
// On exprime la date courante de la règle à vérifier en utc
current = TzUtilities.GetDateTime(rule, year, gmtOffset, rules[index].StandardOffset, DateTimeKind.Utc);
}
if (precedent > current) {
continue;
}
else {
TimeSpan diff = current - precedent;
if (range > diff) {
stdoff = rules[index].StandardOffset;
range = diff;
bestyear = precedent.Year;
}
break;
}
}
}
return stdoff;
}
/// <summary>
/// Obtient une règle en fonction de sa description
/// </summary>
/// <param name="ruleDescription"></param>
/// <returns>
/// # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
/// </returns>
public static Rule GetRule(List<string> ruleDescription)
{
Rule r = new Rule();
Debug.Assert(ruleDescription.Count == 10);
Debug.Assert(ruleDescription[0] == "Rule");
r.Name = ruleDescription[1];
r.StandardOffset = GetHMS(ruleDescription[8]);
r.Letter = ruleDescription[9];
string loyearp = ruleDescription[2];
string hiyearp = ruleDescription[3];
string typep = ruleDescription[4];
// Year work
// Min Year (FROM)
IEnumerable<string> by =
BeginYears.Where(e => itsabbr(loyearp, e));
if (by.Count() == 0) {
r.LowerYear = Int32.Parse(loyearp);
}
else if (by.Count() == 1) {
if (by.ElementAt(0) == BeginYears[0])
r.LowerYear = DateTime.MinValue.Year;
else
r.LowerYear = DateTime.MaxValue.Year;
}
else {
throw new ArgumentException("Multiple inexact match", loyearp);
}
// Max Year (TO)
by = EndYears.Where(e => itsabbr(hiyearp, e));
if (by.Count() == 0) {
r.HighYear = Int32.Parse(hiyearp);
}
else if (by.Count() == 1) {
if (by.ElementAt(0) == EndYears[0])
r.HighYear = DateTime.MinValue.Year;
else if (by.ElementAt(0) == EndYears[1])
r.HighYear = DateTime.MaxValue.Year;
else
r.HighYear = r.LowerYear;
}
else {
throw new ArgumentException("Multiple inexact match", hiyearp);
}
if (r.LowerYear > r.HighYear)
throw new ArgumentException("Starting year greater than ending year");
// Type (TYPE)
switch (typep) {
case "":
case "-":
r.YearType = YearType.none;
break;
case "even":
r.YearType = YearType.even;
break;
case "odd":
r.YearType = YearType.odd;
break;
case "uspres":
r.YearType = YearType.uspres;
break;
case "nonpres":
r.YearType = YearType.nonpres;
break;
case "nonuspres":
r.YearType = YearType.nonuspres;
break;
default:
throw new ArgumentException("Unknown type " + typep);
}
SetRuleSub(r, ruleDescription[5], ruleDescription[6], ruleDescription[7]);
return r;
}
