walltime-js

init = (helpers, TimeZoneTime) -> # Handles a straight number for the on field of a rule. class NumberOnFieldHandler applies: (str) -> !isNaN(parseInt(str, 10)) parseDate: (str) -> parseInt(str, 10) # Handles a "lastSun" type of value for the on field of a rule class LastOnFieldHandler applies: helpers.Months.IsLastDayOfMonthRule parseDate: (str, year, month, qualifier, gmtOffset, daylightOffset) -> helpers.Months.LastDayOfMonthRule str, year, month # Handles a "Sun>=8" type of value for the on field of a rule class CompareOnFieldHandler applies: helpers.Months.IsDayOfMonthRule parseDate: (str, year, month) -> helpers.Months.DayOfMonthByRule str, year, month # A Rule represents an Olson file line describing both a state of time for a given TimeZone # and a transition to daylight savings offset. class Rule constructor: (@name, @_from, @_to, @type, @in, @on, @at, @_save, @letter) -> @from = parseInt @_from, 10 @isMax = false toYear = @from switch @_to when "max" toYear = (helpers.Time.MaxDate()).getUTCFullYear() @isMax = true when "only" toYear = @from else toYear = parseInt @_to, 10 @to = toYear [saveHour, saveMinute] = @_parseTime @_save @save = hours: saveHour mins: saveMinute forZone: (offset) -> @offset = offset # Start with the beginning of the year UTC @fromUTC = helpers.Time.MakeDateFromParts @from, 0, 1, 0, 0, 0 # Apply the passed in time zones offset to get the standard time equivalent of the beginning of the year. @fromUTC = helpers.Time.ApplyOffset @fromUTC, offset # To is the end of the passed in To year, adjusted for GMTOffset and Daylight savings @toUTC = helpers.Time.MakeDateFromParts @to, 11, 31, 23, 59, 59, 999 @toUTC = helpers.Time.ApplyOffset @toUTC, offset setOnUTC: (year, offset, getPrevSave) -> toMonth = helpers.Months.MonthIndex @in onParsed = parseInt @on, 10 toDay = if !isNaN(onParsed) then onParsed else @_parseOnDay @on, year, toMonth # Get the time of day and apply it to the onUTC [toHour, toMinute, atQualifier] = @_parseTime @at # The end time here is not inclusive, we adjust it by 1 millisecond @onUTC = helpers.Time.MakeDateFromParts year, toMonth, toDay, toHour, toMinute @onUTC.setUTCMilliseconds(@onUTC.getUTCMilliseconds() - 1) @atQualifier = if atQualifier != '' then atQualifier else "w" @onUTC = helpers.Time.QualifiedTimeToUTC @onUTC, @atQualifier, offset, => getPrevSave(@) @onSort = "#{toMonth}-#{toDay}-#{@onUTC.getUTCHours()}-#{@onUTC.getUTCMinutes()}" appliesToUTC: (dt) -> @fromUTC <= dt <= @toUTC # Parse the string that represents the day of the month in the "on" field of a rule. # In addition to an actual number this can be strings like "lastSun", "Sun>=8" representing # the last Sunday of the month or the first Sunday on or after the 8th day of the month (second Sunday of the month) _parseOnDay: (onStr, year, month) -> handlers = [new NumberOnFieldHandler, new LastOnFieldHandler, new CompareOnFieldHandler] for handler in handlers continue unless handler.applies onStr return handler.parseDate onStr, year, month throw new Error "Unable to parse 'on' field for #{@name}|#{@_from}|#{@_to}|#{onStr}" _parseTime: (atStr) -> helpers.Time.ParseTime atStr class RuleSet constructor: (@rules = [], @timeZone) -> # Update the rules offsets min = null max = null endYears = {} beginYears = {} for rule in @rules # In the first pass through, we won't have accurate end's rule.forZone @timeZone.offset, -> helpers.noSave if min == null or rule.from < min min = rule.from if max == null or rule.to > max max = rule.to endYears[rule.to] = endYears[rule.to] || [] endYears[rule.to].push rule beginYears[rule.from] = beginYears[rule.from] || [] beginYears[rule.from].push rule # Store these for later range checks on rules. @minYear = min @maxYear = max commonUpdateYearEnds = (end = "toUTC", years = endYears) => for own year, rules of years # Get the rules that apply for that year yearRules = @allThatAppliesTo rules[0][end] continue if yearRules.length < 1 # We only care about the last rule that gets applied for the year # We need to sort here by the on time # TODO: (kind of cheating by only sorting by month) rules = @_sortRulesByOnTime rules lastRule = yearRules.slice(-1)[0] # Keep it moving if no save to apply continue if lastRule.save.hours == 0 and lastRule.save.mins == 0 for rule in rules rule[end] = helpers.Time.ApplySave rule[end], lastRule.save # Follow up and check each end year for a last rule with a save value. commonUpdateYearEnds "toUTC", endYears # The begin times could also have a save applied that we missed. commonUpdateYearEnds "fromUTC", beginYears allThatAppliesTo: (dt) -> # TODO: Pre-check for year outside of min and max. (rule for rule in @rules when rule.appliesToUTC dt) getWallTimeForUTC: (dt) -> # Get the rules for this year rules = @allThatAppliesTo dt # If no rules apply, return standard time if rules.length < 1 return new TimeZoneTime(dt, @timeZone, helpers.noSave) # Sort the rules. rules = @_sortRulesByOnTime rules getPrevRuleSave = (r) -> idx = rules.indexOf r # Return begin of year save if this is the first rule (or not found) if idx < 1 if rules.length < 1 return helpers.noSave # TODO: We are cheating here by choosing the last rule for the current year, # we should have to check the previous years last rule. return rules.slice(-1)[0].save # Return the previous rules save value otherwise rules[idx-1].save # Update the onTimes for each of the rules for rule in rules rule.setOnUTC dt.getUTCFullYear(), @timeZone.offset, getPrevRuleSave # Get rules that applied to us appliedRules = (rule for rule in rules when rule.onUTC.getTime() < dt.getTime()) # TODO: We are cheating here by choosing the last rule for the current year, # we should have to check the previous years last rule. lastSave = if rules.length < 1 then helpers.noSave else rules.slice(-1)[0].save if appliedRules.length > 0 # Get the last rule that applied, then use its save time lastSave = appliedRules.slice(-1)[0].save new TimeZoneTime(dt, @timeZone, lastSave) getUTCForWallTime: (dt) -> # All of our rule begins and ends are in UTC time, so try to translate at least by the offset. utcStd = helpers.Time.StandardTimeToUTC @timeZone.offset, dt rules = (rule for rule in @rules when rule.appliesToUTC utcStd) # If no rules apply, return standard time if rules.length < 1 return utcStd # Sort the rules. rules = @_sortRulesByOnTime rules getPrevRuleSave = (r) -> idx = rules.indexOf r # Return begin of year save if this is the first rule (or not found) if idx < 1 if rules.length < 1 return helpers.noSave # TODO: We are cheating here by choosing the last rule for the current year, # we should have to check the previous years last rule. return rules.slice(-1)[0].save # Return the previous rules save value otherwise rules[idx-1].save # Update the onTimes for each of the rules for rule in rules rule.setOnUTC utcStd.getUTCFullYear(), @timeZone.offset, getPrevRuleSave # Get rules that applied to us appliedRules = (rule for rule in rules when rule.onUTC.getTime() < utcStd.getTime()) # TODO: We are cheating here by choosing the last rule for the current year, # we should have to check the previous years last rule. lastSave = if rules.length < 1 then helpers.noSave else rules.slice(-1)[0].save if appliedRules.length > 0 # Get the last rule that applied, then use its save time lastSave = appliedRules.slice(-1)[0].save helpers.Time.WallTimeToUTC @timeZone.offset, lastSave, dt getYearEndDST: (dt) -> year = if typeof dt == number then dt else dt.getUTCFullYear() # Get the last second of the passed in year. utcStd = helpers.Time.StandardTimeToUTC @timeZone.offset, year, 11, 31, 23, 59, 59 rules = (rule for rule in @rules when rule.appliesToUTC utcStd) # If no rules apply, return no save if rules.length < 1 return helpers.noSave # Sort the rules. rules = @_sortRulesByOnTime rules getPrevRuleSave = (r) -> idx = rules.indexOf r # Return no save if this is the first rule (or not found) if idx < 1 return helpers.noSave # Return the previous rules save value otherwise rules[idx-1].save # Update the onTimes for each of the rules for rule in rules rule.setOnUTC utcStd.getUTCFullYear(), @timeZone.offset, getPrevRuleSave # Get rules that applied to us appliedRules = (rule for rule in rules when rule.onUTC.getTime() < utcStd.getTime()) # Return no save if no rules applied. lastSave = helpers.noSave if appliedRules.length > 0 # Get the last rule that applied, then use its save time lastSave = appliedRules.slice(-1)[0].save # Return the lastSave that applied lastSave isAmbiguous: (dt) -> # Get the standard version of the wall time that is passed in. utcStd = helpers.Time.StandardTimeToUTC @timeZone.offset, dt rules = (rule for rule in @rules when rule.appliesToUTC utcStd) # If no rules apply, return false if rules.length < 1 return false # Sort the rules. rules = @_sortRulesByOnTime rules getPrevRuleSave = (r) -> idx = rules.indexOf r # Return no save if this is the first rule (or not found) if idx < 1 return helpers.noSave # Return the previous rules save value otherwise rules[idx-1].save # Update the onTimes for each of the rules for rule in rules rule.setOnUTC utcStd.getUTCFullYear(), @timeZone.offset, getPrevRuleSave # Get rules that applied to appliedRules = (rule for rule in rules when rule.onUTC.getTime() <= utcStd.getTime()-1) # Return false if no rules applied return false if appliedRules.length < 1 # Get the last rule that applied, then check it's end time lastRule = appliedRules.slice(-1)[0] prevSave = getPrevRuleSave lastRule totalMinutes = prev: (prevSave.hours * 60) + prevSave.mins last: (lastRule.save.hours * 60) + lastRule.save.mins # There was no change in save, so there can be no ambiguity here. return false if totalMinutes.prev == totalMinutes.last # if the previous rule had a dst, and this one doesn't, it's a "fall back" # if the previous rule had no dst and this one does it's a "spring forward" springForward = totalMinutes.prev < totalMinutes.last makeAmbigRange = (begin, minutesOff) -> ambigRange = begin: helpers.Time.MakeDateFromTimeStamp begin.getTime() + 1 ambigRange.end = helpers.Time.Add ambigRange.begin, 0, minutesOff # Since we could have applied a -minutesOff, switch the begin and end if they have swapped. if ambigRange.begin.getTime() > ambigRange.end.getTime() tmp = ambigRange.begin ambigRange.begin = ambigRange.end ambigRange.end = tmp ambigRange # if we are springing forward, the last rules save should be added to determine the range # if we are falling back, the previous save should be used to set the beginning. minsOff = if springForward then totalMinutes.last else -totalMinutes.prev range = makeAmbigRange lastRule.onUTC, minsOff # Apply the previous save value to the standard time for fair comparison utcStd = helpers.Time.WallTimeToUTC @timeZone.offset, prevSave, dt # Return whether or not we are in the ambiguous range range.begin <= utcStd <= range.end _sortRulesByOnTime: (rules) -> rules.sort (a, b) -> (helpers.Months.MonthIndex a.in) - (helpers.Months.MonthIndex b.in) lib = Rule: Rule RuleSet: RuleSet OnFieldHandlers: NumberHandler: NumberOnFieldHandler LastHandler: LastOnFieldHandler CompareHandler: CompareOnFieldHandler lib if typeof window == 'undefined' req_helpers = require "./helpers" req_TimeZoneTime = require "./timezonetime" module.exports = init(req_helpers, req_TimeZoneTime) else if typeof define != 'undefined' define ["olson/helpers", "olson/timezonetime"], init else @.WallTime or= {} @.WallTime.rule = init(@.WallTime.helpers, @.WallTime.TimeZoneTime)