class ActiveSupport::TimeZone

def <=>(zone)
  return unless zone.respond_to? :utc_offset
  result = (utc_offset <=> zone.utc_offset)
  result = (name <=> zone.name) if result == 0
  result
end

def =~(re)
  re === name || re === MAPPING[name]
end

def []: (ActiveSupport::TimeZone arg) -> untyped

def [](arg)
  case arg
  when self
    arg
  when String
    begin
      @lazy_zones_map[arg] ||= create(arg)
    rescue TZInfo::InvalidTimezoneIdentifier
      nil
    end
  when TZInfo::Timezone
    @lazy_zones_map[arg.name] ||= create(arg.name, nil, arg)
  when Numeric, ActiveSupport::Duration
    arg *= 3600 if arg.abs <= 13
    all.find { |z| z.utc_offset == arg.to_i }
  else
    raise ArgumentError, "invalid argument to TimeZone[]: #{arg.inspect}"
  end
end

def all
  @zones ||= zones_map.values.sort
end

def at(*args)
  Time.at(*args).utc.in_time_zone(self)
end

def clear # :nodoc:
  @lazy_zones_map = Concurrent::Map.new
  @country_zones  = Concurrent::Map.new
  @zones = nil
  @zones_map = nil
end

def country_zones(country_code)
  code = country_code.to_s.upcase
  @country_zones[code] ||= load_country_zones(code)
end

def encode_with(coder) # :nodoc:
  coder.tag = "!ruby/object:#{self.class}"
  coder.map = { "name" => tzinfo.name }
end

def find_tzinfo(name)
  TZInfo::Timezone.get(MAPPING[name] || name)
end

def formatted_offset(colon = true, alternate_utc_string = nil)
  utc_offset == 0 && alternate_utc_string || self.class.seconds_to_utc_offset(utc_offset, colon)
end

def init_with(coder) # :nodoc:
  initialize(coder["name"])
end

def initialize(name, utc_offset = nil, tzinfo = nil)
  @name = name
  @utc_offset = utc_offset
  @tzinfo = tzinfo || TimeZone.find_tzinfo(name)
end

def iso8601(str)
  # Historically `Date._iso8601(nil)` returns `{}`, but in the `date` gem versions `3.2.1`, `3.1.2`, `3.0.2`,
  # and `2.0.1`, `Date._iso8601(nil)` raises `TypeError` https://github.com/ruby/date/issues/39
  # Future `date` releases are expected to revert back to the original behavior.
  raise ArgumentError, "invalid date" if str.nil?
  parts = Date._iso8601(str)
  year = parts.fetch(:year)
  if parts.key?(:yday)
    ordinal_date = Date.ordinal(year, parts.fetch(:yday))
    month = ordinal_date.month
    day = ordinal_date.day
  else
    month = parts.fetch(:mon)
    day = parts.fetch(:mday)
  end
  time = Time.new(
    year,
    month,
    day,
    parts.fetch(:hour, 0),
    parts.fetch(:min, 0),
    parts.fetch(:sec, 0) + parts.fetch(:sec_fraction, 0),
    parts.fetch(:offset, 0)
  )
  if parts[:offset]
    TimeWithZone.new(time.utc, self)
  else
    TimeWithZone.new(nil, self, time)
  end
rescue Date::Error, KeyError
  raise ArgumentError, "invalid date"
end

def load_country_zones(code)
  country = TZInfo::Country.get(code)
  country.zone_identifiers.flat_map do |tz_id|
    if MAPPING.value?(tz_id)
      MAPPING.inject([]) do |memo, (key, value)|
        memo << self[key] if value == tz_id
        memo
      end
    else
      create(tz_id, nil, TZInfo::Timezone.get(tz_id))
    end
  end.sort!
end

def local(*args)
  time = Time.utc(*args)
  ActiveSupport::TimeWithZone.new(nil, self, time)
end

def local_to_utc(time, dst = true)
  tzinfo.local_to_utc(time, dst)
end

def match?(re)
  (re == name) || (re == MAPPING[name]) ||
    ((Regexp === re) && (re.match?(name) || re.match?(MAPPING[name])))
end

def new(name)
  self[name]
end

def now
  time_now.utc.in_time_zone(self)
end

def parse(str, now = now())
  parts_to_time(Date._parse(str, false), now)
end

def parts_to_time(parts, now)
  raise ArgumentError, "invalid date" if parts.nil?
  return if parts.empty?
  if parts[:seconds]
    time = Time.at(parts[:seconds])
  else
    time = Time.new(
      parts.fetch(:year, now.year),
      parts.fetch(:mon, now.month),
      parts.fetch(:mday, parts[:year] || parts[:mon] ? 1 : now.day),
      parts.fetch(:hour, 0),
      parts.fetch(:min, 0),
      parts.fetch(:sec, 0) + parts.fetch(:sec_fraction, 0),
      parts.fetch(:offset, 0)
    )
  end
  if parts[:offset] || parts[:seconds]
    TimeWithZone.new(time.utc, self)
  else
    TimeWithZone.new(nil, self, time)
  end
end

def period_for_local(time, dst = true)
  tzinfo.period_for_local(time, dst) { |periods| periods.last }
end

def period_for_utc(time)
  tzinfo.period_for_utc(time)
end

def periods_for_local(time) # :nodoc:
  tzinfo.periods_for_local(time)
end

def rfc3339(str)
  parts = Date._rfc3339(str)
  raise ArgumentError, "invalid date" if parts.empty?
  time = Time.new(
    parts.fetch(:year),
    parts.fetch(:mon),
    parts.fetch(:mday),
    parts.fetch(:hour),
    parts.fetch(:min),
    parts.fetch(:sec) + parts.fetch(:sec_fraction, 0),
    parts.fetch(:offset)
  )
  TimeWithZone.new(time.utc, self)
end

def seconds_to_utc_offset(seconds, colon = true)
  format = colon ? UTC_OFFSET_WITH_COLON : UTC_OFFSET_WITHOUT_COLON
  sign = (seconds < 0 ? "-" : "+")
  hours = seconds.abs / 3600
  minutes = (seconds.abs % 3600) / 60
  format % [sign, hours, minutes]
end

def strptime(str, format, now = now())
  parts_to_time(DateTime._strptime(str, format), now)
end

def time_now
  Time.now
end

def to_s
  "(GMT#{formatted_offset}) #{name}"
end

def today
  tzinfo.now.to_date
end

def tomorrow
  today + 1
end

def us_zones
  country_zones(:us)
end

def utc_offset
  @utc_offset || tzinfo&.current_period&.base_utc_offset
end

def utc_to_local(time)
  tzinfo.utc_to_local(time).yield_self do |t|
    ActiveSupport.utc_to_local_returns_utc_offset_times ?
      t : Time.utc(t.year, t.month, t.day, t.hour, t.min, t.sec, t.sec_fraction * 1_000_000)
  end
end

def yesterday
  today - 1
end

def zones_map
  @zones_map ||= MAPPING.each_with_object({}) do |(name, _), zones|
    timezone = self[name]
    zones[name] = timezone if timezone
  end
end