--- /dev/null
+#--
+# Copyright (c) 2006 Philip Ross
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+#++
+
+require 'tzinfo/time_or_datetime'
+require 'tzinfo/timezone_info'
+require 'tzinfo/timezone_offset_info'
+require 'tzinfo/timezone_period'
+require 'tzinfo/timezone_transition_info'
+
+module TZInfo
+ # Thrown if no offsets have been defined when calling period_for_utc or
+ # periods_for_local. Indicates an error in the timezone data.
+ class NoOffsetsDefined < StandardError
+ end
+
+ # Represents a (non-linked) timezone defined in a data module.
+ class DataTimezoneInfo < TimezoneInfo #:nodoc:
+
+ # Constructs a new TimezoneInfo with its identifier.
+ def initialize(identifier)
+ super(identifier)
+ @offsets = {}
+ @transitions = []
+ @previous_offset = nil
+ @transitions_index = nil
+ end
+
+ # Defines a offset. The id uniquely identifies this offset within the
+ # timezone. utc_offset and std_offset define the offset in seconds of
+ # standard time from UTC and daylight savings from standard time
+ # respectively. abbreviation describes the timezone offset (e.g. GMT, BST,
+ # EST or EDT).
+ #
+ # The first offset to be defined is treated as the offset that applies
+ # until the first transition. This will usually be in Local Mean Time (LMT).
+ #
+ # ArgumentError will be raised if the id is already defined.
+ def offset(id, utc_offset, std_offset, abbreviation)
+ raise ArgumentError, 'Offset already defined' if @offsets.has_key?(id)
+
+ offset = TimezoneOffsetInfo.new(utc_offset, std_offset, abbreviation)
+ @offsets[id] = offset
+ @previous_offset = offset unless @previous_offset
+ end
+
+ # Defines a transition. Transitions must be defined in chronological order.
+ # ArgumentError will be raised if a transition is added out of order.
+ # offset_id refers to an id defined with offset. ArgumentError will be
+ # raised if the offset_id cannot be found. numerator_or_time and
+ # denomiator specify the time the transition occurs as. See
+ # TimezoneTransitionInfo for more detail about specifying times.
+ def transition(year, month, offset_id, numerator_or_time, denominator = nil)
+ offset = @offsets[offset_id]
+ raise ArgumentError, 'Offset not found' unless offset
+
+ if @transitions_index
+ if year < @last_year || (year == @last_year && month < @last_month)
+ raise ArgumentError, 'Transitions must be increasing date order'
+ end
+
+ # Record the position of the first transition with this index.
+ index = transition_index(year, month)
+ @transitions_index[index] ||= @transitions.length
+
+ # Fill in any gaps
+ (index - 1).downto(0) do |i|
+ break if @transitions_index[i]
+ @transitions_index[i] = @transitions.length
+ end
+ else
+ @transitions_index = [@transitions.length]
+ @start_year = year
+ @start_month = month
+ end
+
+ @transitions << TimezoneTransitionInfo.new(offset, @previous_offset,
+ numerator_or_time, denominator)
+ @last_year = year
+ @last_month = month
+ @previous_offset = offset
+ end
+
+ # Returns the TimezonePeriod for the given UTC time.
+ # Raises NoOffsetsDefined if no offsets have been defined.
+ def period_for_utc(utc)
+ unless @transitions.empty?
+ utc = TimeOrDateTime.wrap(utc)
+ index = transition_index(utc.year, utc.mon)
+
+ start_transition = nil
+ start = transition_before_end(index)
+ if start
+ start.downto(0) do |i|
+ if @transitions[i].at <= utc
+ start_transition = @transitions[i]
+ break
+ end
+ end
+ end
+
+ end_transition = nil
+ start = transition_after_start(index)
+ if start
+ start.upto(@transitions.length - 1) do |i|
+ if @transitions[i].at > utc
+ end_transition = @transitions[i]
+ break
+ end
+ end
+ end
+
+ if start_transition || end_transition
+ TimezonePeriod.new(start_transition, end_transition)
+ else
+ # Won't happen since there are transitions. Must always find one
+ # transition that is either >= or < the specified time.
+ raise 'No transitions found in search'
+ end
+ else
+ raise NoOffsetsDefined, 'No offsets have been defined' unless @previous_offset
+ TimezonePeriod.new(nil, nil, @previous_offset)
+ end
+ end
+
+ # Returns the set of TimezonePeriods for the given local time as an array.
+ # Results returned are ordered by increasing UTC start date.
+ # Returns an empty array if no periods are found for the given time.
+ # Raises NoOffsetsDefined if no offsets have been defined.
+ def periods_for_local(local)
+ unless @transitions.empty?
+ local = TimeOrDateTime.wrap(local)
+ index = transition_index(local.year, local.mon)
+
+ result = []
+
+ start_index = transition_after_start(index - 1)
+ if start_index && @transitions[start_index].local_end > local
+ if start_index > 0
+ if @transitions[start_index - 1].local_start <= local
+ result << TimezonePeriod.new(@transitions[start_index - 1], @transitions[start_index])
+ end
+ else
+ result << TimezonePeriod.new(nil, @transitions[start_index])
+ end
+ end
+
+ end_index = transition_before_end(index + 1)
+
+ if end_index
+ start_index = end_index unless start_index
+
+ start_index.upto(transition_before_end(index + 1)) do |i|
+ if @transitions[i].local_start <= local
+ if i + 1 < @transitions.length
+ if @transitions[i + 1].local_end > local
+ result << TimezonePeriod.new(@transitions[i], @transitions[i + 1])
+ end
+ else
+ result << TimezonePeriod.new(@transitions[i], nil)
+ end
+ end
+ end
+ end
+
+ result
+ else
+ raise NoOffsetsDefined, 'No offsets have been defined' unless @previous_offset
+ [TimezonePeriod.new(nil, nil, @previous_offset)]
+ end
+ end
+
+ private
+ # Returns the index into the @transitions_index array for a given year
+ # and month.
+ def transition_index(year, month)
+ index = (year - @start_year) * 2
+ index += 1 if month > 6
+ index -= 1 if @start_month > 6
+ index
+ end
+
+ # Returns the index into @transitions of the first transition that occurs
+ # on or after the start of the given index into @transitions_index.
+ # Returns nil if there are no such transitions.
+ def transition_after_start(index)
+ if index >= @transitions_index.length
+ nil
+ else
+ index = 0 if index < 0
+ @transitions_index[index]
+ end
+ end
+
+ # Returns the index into @transitions of the first transition that occurs
+ # before the end of the given index into @transitions_index.
+ # Returns nil if there are no such transitions.
+ def transition_before_end(index)
+ index = index + 1
+
+ if index <= 0
+ nil
+ elsif index >= @transitions_index.length
+ @transitions.length - 1
+ else
+ @transitions_index[index] - 1
+ end
+ end
+ end
+end
projects / depot.git / blobdiff