Merge pull request #41 from jurriaan/1904-date-fix

Default to 1900 date system

2 files changed, 9 insertions, 17 deletions

diff --git a/lib/axlsx/workbook/workbook.rb b/lib/axlsx/workbook/workbook.rb
index b3b10fac..cbb85349 100644
--- a/lib/axlsx/workbook/workbook.rb
+++ b/lib/axlsx/workbook/workbook.rb
@@ -99,25 +99,17 @@ require 'axlsx/workbook/shared_strings_table.rb'
 
     # Creates a new Workbook
     # The recomended way to work with workbooks is via Package#workbook
-    # @option options [Boolean] date1904. If this is not specified, we try to determine if the platform is bsd/darwin and set date1904 to true automatically.    
+    # @option options [Boolean] date1904. If this is not specified, date1904 is set to false. Office 2011 for Mac defaults to false.
     def initialize(options={})
       @styles = Styles.new
       @worksheets = SimpleTypedList.new Worksheet
       @drawings = SimpleTypedList.new Drawing
       @charts = SimpleTypedList.new Chart
       @images = SimpleTypedList.new Pic
-      self.date1904= options[:date1904].nil? ? is_bsd? : options[:date1904]
+      self.date1904= !options[:date1904].nil? && options[:date1904]
       yield self if block_given?      
     end
 
-    # Uses RUBY_PLATFORM constant to determine if the OS is freebsd or darwin
-    # based on this value we attempt to set date1904.
-    # @return [Boolean]
-    def is_bsd?
-      platform = RUBY_PLATFORM.downcase
-      platform.include?('freebsd') || platform.include?('darwin')
-    end
-
     # Instance level access to the class variable 1904
     # @return [Boolean]
     def date1904() @@date1904; end    
diff --git a/lib/axlsx/workbook/worksheet/date_time_converter.rb b/lib/axlsx/workbook/worksheet/date_time_converter.rb
index 5a572781..d2d9a014 100644
--- a/lib/axlsx/workbook/worksheet/date_time_converter.rb
+++ b/lib/axlsx/workbook/worksheet/date_time_converter.rb
@@ -9,8 +9,8 @@ module Axlsx
     # @param [Date] date the date to be serialized
     # @return [Numeric]
     def self.date_to_serial(date)
-      epoc = Axlsx::Workbook::date1904 ? Date.new(1904) : Date.new(1899, 12, 30)
-      (date-epoc).to_f
+      epoch = Axlsx::Workbook::date1904 ? Date.new(1904) : Date.new(1899, 12, 30)
+      (date-epoch).to_f
     end
 
     # The time_to_serial methond converts a Time object its excel serialized form.
@@ -18,12 +18,12 @@ module Axlsx
     # @return [Numeric]
     def self.time_to_serial(time)
       # Using hardcoded offsets here as some operating systems will not except
-      # a 'negative' offset from the ruby epoc.
-      epoc1900 = -2209161600 # Time.utc(1899, 12, 30).to_i
-      epoc1904 = -2082844800 # Time.utc(1904, 1, 1).to_i
+      # a 'negative' offset from the ruby epoch.
+      epoch1900 = -2209161600 # Time.utc(1899, 12, 30).to_i
+      epoch1904 = -2082844800 # Time.utc(1904, 1, 1).to_i
       seconds_per_day = 86400 # 60*60*24
-      epoc = Axlsx::Workbook::date1904 ? epoc1904 : epoc1900
-      (time.to_f - epoc)/seconds_per_day
+      epoch = Axlsx::Workbook::date1904 ? epoch1904 : epoch1900
+      (time.to_f - epoch)/seconds_per_day
     end
   end
 end