module Chronic
# Returns a Hash of default configuration options.
DEFAULT_OPTIONS = {
:context => :future,
:now => nil,
:guess => true,
:ambiguous_time_range => 6,
:endian_precedence => [:middle, :little],
:ambiguous_year_future_bias => 50
}
SEC_PER_DAY = 86400
class << self
# Parses a string containing a natural language date or time.
#
# If the parser can find a date or time, either a Time or Chronic::Span
# will be returned (depending on the value of `:guess`). If no
# date or time can be found, `nil` will be returned.
#
# text - The String text to parse.
# opts - An optional Hash of configuration options:
# :context - If your string represents a birthday, you can set
# this value to :past and if an ambiguous string is
# given, it will assume it is in the past.
# :now - Time, all computations will be based off of time
# instead of Time.now.
# :guess - By default the parser will guess a single point in time
# for the given date or time. If you'd rather have the
# entire time span returned, set this to false
# and a Chronic::Span will be returned.
# :ambiguous_time_range - If an Integer is given, ambiguous times
# (like 5:00) will be assumed to be within the range of
# that time in the AM to that time in the PM. For
# example, if you set it to `7`, then the parser will
# look for the time between 7am and 7pm. In the case of
# 5:00, it would assume that means 5:00pm. If `:none`
# is given, no assumption will be made, and the first
# matching instance of that time will be used.
# :endian_precedence - By default, Chronic will parse "03/04/2011"
# as the fourth day of the third month. Alternatively you
# can tell Chronic to parse this as the third day of the
# fourth month by setting this to [:little, :middle].
# :ambiguous_year_future_bias - When parsing two digit years
# (ie 79) unlike Rubys Time class, Chronic will attempt
# to assume the full year using this figure. Chronic will
# look x amount of years into the future and past. If the
# two digit year is `now + x years` it's assumed to be the
# future, `now - x years` is assumed to be the past.
#
# Returns a new Time object, or Chronic::Span if :guess option is false.
def parse(text, opts={})
options = DEFAULT_OPTIONS.merge opts
# ensure the specified options are valid
(opts.keys - DEFAULT_OPTIONS.keys).each do |key|
raise ArgumentError, "#{key} is not a valid option key."
end
unless [:past, :future, :none].include?(options[:context])
raise ArgumentError, "Invalid context, :past/:future only"
end
options[:text] = text
Chronic.now = options[:now] || Chronic.time_class.now
# tokenize words
tokens = tokenize(text, options)
if Chronic.debug
puts "+#{'-' * 51}\n| #{tokens}\n+#{'-' * 51}"
end
span = tokens_to_span(tokens, options)
if span
options[:guess] ? guess(span) : span
end
end
# Clean up the specified text ready for parsing.
#
# Clean up the string by stripping unwanted characters, converting
# idioms to their canonical form, converting number words to numbers
# (three => 3), and converting ordinal words to numeric
# ordinals (third => 3rd)
#
# text - The String text to normalize.
#
# Examples:
#
# Chronic.pre_normalize('first day in May')
# #=> "1st day in may"
#
# Chronic.pre_normalize('tomorrow after noon')
# #=> "next day future 12:00"
#
# Chronic.pre_normalize('one hundred and thirty six days from now')
# #=> "136 days future this second"
#
# Returns a new String ready for Chronic to parse.
def pre_normalize(text)
text = text.to_s.downcase
text.gsub!(/\./, ':')
text.gsub!(/['"]/, '')
text.gsub!(/,/, ' ')
text.gsub!(/\bsecond (of|day|month|hour|minute|second)\b/, '2nd \1')
text = Numerizer.numerize(text)
text.gsub!(/ \-(\d{4})\b/, ' tzminus\1')
text.gsub!(/([\/\-\,\@])/) { ' ' + $1 + ' ' }
text.gsub!(/(?:^|\s)0(\d+:\d+\s*pm?\b)/, '\1')
text.gsub!(/\btoday\b/, 'this day')
text.gsub!(/\btomm?orr?ow\b/, 'next day')
text.gsub!(/\byesterday\b/, 'last day')
text.gsub!(/\bnoon\b/, '12:00pm')
text.gsub!(/\bmidnight\b/, '24:00')
text.gsub!(/\bnow\b/, 'this second')
text.gsub!(/\b(?:ago|before(?: now)?)\b/, 'past')
text.gsub!(/\bthis (?:last|past)\b/, 'last')
text.gsub!(/\b(?:in|during) the (morning)\b/, '\1')
text.gsub!(/\b(?:in the|during the|at) (afternoon|evening|night)\b/, '\1')
text.gsub!(/\btonight\b/, 'this night')
text.gsub!(/\b\d+:?\d*[ap]\b/,'\0m')
text.gsub!(/(\d)([ap]m|oclock)\b/, '\1 \2')
text.gsub!(/\b(hence|after|from)\b/, 'future')
text
end
# Convert number words to numbers (three => 3, fourth => 4th).
#
# text - The String to convert.
#
# Returns a new String with words converted to numbers.
def numericize_numbers(text)
warn "Chronic.numericize_numbers will be deprecated in version 0.7.0. Please use Chronic::Numerizer.numerize instead"
Numerizer.numerize(text)
end
# Guess a specific time within the given span.
#
# span - The Chronic::Span object to calcuate a guess from.
#
# Returns a new Time object or a new Date object
def guess(span)
if span.width > 1
if span.width == SEC_PER_DAY
(span.begin + (span.width / 2)).to_date
else
span.begin + (span.width / 2)
end
else
span.begin
end
end
# List of Handler definitions. See #parse for a list of options this
# method accepts.
#
# options - An optional Hash of configuration options:
# :endian_precedence -
#
# Returns A Hash of Handler definitions.
def definitions(options={})
options[:endian_precedence] ||= [:middle, :little]
@definitions ||= {
:time => [
Handler.new([:repeater_time, :repeater_day_portion?], nil)
],
:date => [
Handler.new([:repeater_day_name, :repeater_month_name, :scalar_day, :repeater_time, :separator_slash_or_dash?, :time_zone, :scalar_year], :handle_rdn_rmn_sd_t_tz_sy),
Handler.new([:repeater_day_name, :repeater_month_name, :scalar_day], :handle_rdn_rmn_sd),
Handler.new([:repeater_day_name, :repeater_month_name, :scalar_day, :scalar_year], :handle_rdn_rmn_sd_sy),
Handler.new([:repeater_day_name, :repeater_month_name, :ordinal_day], :handle_rdn_rmn_od),
Handler.new([:scalar_year, :separator_slash_or_dash, :scalar_month, :separator_slash_or_dash, :scalar_day, :repeater_time, :time_zone], :handle_sy_sm_sd_t_tz),
Handler.new([:repeater_month_name, :scalar_day, :scalar_year], :handle_rmn_sd_sy),
Handler.new([:repeater_month_name, :ordinal_day, :scalar_year], :handle_rmn_od_sy),
Handler.new([:repeater_month_name, :scalar_day, :scalar_year, :separator_at?, 'time?'], :handle_rmn_sd_sy),
Handler.new([:repeater_month_name, :ordinal_day, :scalar_year, :separator_at?, 'time?'], :handle_rmn_od_sy),
Handler.new([:repeater_month_name, :scalar_day, :separator_at?, 'time?'], :handle_rmn_sd),
Handler.new([:repeater_time, :repeater_day_portion?, :separator_on?, :repeater_month_name, :scalar_day], :handle_rmn_sd_on),
Handler.new([:repeater_month_name, :ordinal_day, :separator_at?, 'time?'], :handle_rmn_od),
Handler.new([:ordinal_day, :repeater_month_name, :scalar_year, :separator_at?, 'time?'], :handle_od_rmn_sy),
Handler.new([:ordinal_day, :repeater_month_name, :separator_at?, 'time?'], :handle_od_rmn),
Handler.new([:scalar_year, :repeater_month_name, :ordinal_day], :handle_sy_rmn_od),
Handler.new([:repeater_time, :repeater_day_portion?, :separator_on?, :repeater_month_name, :ordinal_day], :handle_rmn_od_on),
Handler.new([:repeater_month_name, :scalar_year], :handle_rmn_sy),
Handler.new([:scalar_day, :repeater_month_name, :scalar_year, :separator_at?, 'time?'], :handle_sd_rmn_sy),
Handler.new([:scalar_day, :repeater_month_name, :separator_at?, 'time?'], :handle_sd_rmn),
Handler.new([:scalar_year, :separator_slash_or_dash, :scalar_month, :separator_slash_or_dash, :scalar_day, :separator_at?, 'time?'], :handle_sy_sm_sd),
Handler.new([:scalar_month, :separator_slash_or_dash, :scalar_day], :handle_sm_sd),
Handler.new([:scalar_month, :separator_slash_or_dash, :scalar_year], :handle_sm_sy)
],
# tonight at 7pm
:anchor => [
Handler.new([:grabber?, :repeater, :separator_at?, :repeater?, :repeater?], :handle_r),
Handler.new([:grabber?, :repeater, :repeater, :separator_at?, :repeater?, :repeater?], :handle_r),
Handler.new([:repeater, :grabber, :repeater], :handle_r_g_r)
],
# 3 weeks from now, in 2 months
:arrow => [
Handler.new([:scalar, :repeater, :pointer], :handle_s_r_p),
Handler.new([:pointer, :scalar, :repeater], :handle_p_s_r),
Handler.new([:scalar, :repeater, :pointer, 'anchor'], :handle_s_r_p_a)
],
# 3rd week in march
:narrow => [
Handler.new([:ordinal, :repeater, :separator_in, :repeater], :handle_o_r_s_r),
Handler.new([:ordinal, :repeater, :grabber, :repeater], :handle_o_r_g_r)
]
}
endians = [
Handler.new([:scalar_month, :separator_slash_or_dash, :scalar_day, :separator_slash_or_dash, :scalar_year, :separator_at?, 'time?'], :handle_sm_sd_sy),
Handler.new([:scalar_day, :separator_slash_or_dash, :scalar_month, :separator_slash_or_dash, :scalar_year, :separator_at?, 'time?'], :handle_sd_sm_sy)
]
case endian = Array(options[:endian_precedence]).first
when :little
@definitions[:endian] = endians.reverse
when :middle
@definitions[:endian] = endians
else
raise ArgumentError, "Unknown endian option '#{endian}'"
end
@definitions
end
# Construct a new time object determining possible month overflows
# and leap years.
#
# year - Integer year.
# month - Integer month.
# day - Integer day.
# hour - Integer hour.
# minute - Integer minute.
# second - Integer second.
#
# Returns a new Time object constructed from these params.
def construct(year, month = 1, day = 1, hour = 0, minute = 0, second = 0)
if second >= 60
minute += second / 60
second = second % 60
end
if minute >= 60
hour += minute / 60
minute = minute % 60
end
if hour >= 24
day += hour / 24
hour = hour % 24
end
# determine if there is a day overflow. this is complicated by our crappy calendar
# system (non-constant number of days per month)
day <= 56 || raise("day must be no more than 56 (makes month resolution easier)")
if day > 28
# no month ever has fewer than 28 days, so only do this if necessary
leap_year_month_days = [31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
common_year_month_days = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
days_this_month = Date.leap?(year) ? leap_year_month_days[month - 1] : common_year_month_days[month - 1]
if day > days_this_month
month += day / days_this_month
day = day % days_this_month
end
end
if month > 12
if month % 12 == 0
year += (month - 12) / 12
month = 12
else
year += month / 12
month = month % 12
end
end
Chronic.time_class.local(year, month, day, hour, minute, second)
end
private
def tokenize(text, options)
text = pre_normalize(text)
tokens = text.split(' ').map { |word| Token.new(word) }
[Repeater, Grabber, Pointer, Scalar, Ordinal, Separator, TimeZone].each do |tok|
tok.scan(tokens, options)
end
tokens.select { |token| token.tagged? }
end
def tokens_to_span(tokens, options)
definitions = definitions(options)
(definitions[:endian] + definitions[:date]).each do |handler|
if handler.match(tokens, definitions)
good_tokens = tokens.select { |o| !o.get_tag Separator }
return handler.invoke(:date, good_tokens, options)
end
end
definitions[:anchor].each do |handler|
if handler.match(tokens, definitions)
good_tokens = tokens.select { |o| !o.get_tag Separator }
return handler.invoke(:anchor, good_tokens, options)
end
end
definitions[:arrow].each do |handler|
if handler.match(tokens, definitions)
good_tokens = tokens.reject { |o| o.get_tag(SeparatorAt) || o.get_tag(SeparatorSlashOrDash) || o.get_tag(SeparatorComma) }
return handler.invoke(:arrow, good_tokens, options)
end
end
definitions[:narrow].each do |handler|
if handler.match(tokens, definitions)
return handler.invoke(:narrow, tokens, options)
end
end
puts "-none" if Chronic.debug
return nil
end
end
# Internal exception
class ChronicPain < Exception
end
end