A very old Ruby script to email me reminders of when people's birthdays are coming up

birthdays.rb

#!/usr/bin/ruby -w
# encoding: US-ASCII

require 'date'

def usage
  STDERR.print <<EOUSAGE
It is intended that this script should be run from cron.daily, or
once every few days by some other means.

Usage:
  birthdays [ -h | --help ]
                             Display this usage message and exit
            [ -m <email-address> | --mail=<email-address> ]
                             Instead of reporting to standard output,
                             silently send a reminder by email.
            -d <n> | --days=<n>
                             Report on any birthdays coming up in
                             the next <n> days.

EOUSAGE
end

require 'getoptlong'

options = GetoptLong.new(

  [ "--help", "-h", GetoptLong::NO_ARGUMENT ],
  [ "--sort", "-s", GetoptLong::NO_ARGUMENT ],
  [ "--mail", "-m", GetoptLong::REQUIRED_ARGUMENT ],
  [ "--days", "-d", GetoptLong::REQUIRED_ARGUMENT ]

)

mail_report_address = nil
days_in_advance = nil

birthday_line_re = Regexp.new( '^((XXXX|\d{4})-(\d\d)-(\d\d)) (.*)$' )
filename = ENV['HOME'] + "/.birthdays"

begin

  options.each do |opt, arg|

    case opt
    when "--help"
      usage
      exit
    when "--mail"
      mail_report_address = arg
      unless mail_report_address =~ /^.+@[^\.].*$/
        raise "'#{mail_report_address}' doesn't look like a valid email address."
      end
    when "--sort"
      lines = open( filename ) { |f| f.readlines }.find_all { |l| l =~ birthday_line_re }
      lines.sort_by { |k|
        k =~ birthday_line_re
        $3 + "-" + $4 + "-" + $5
      }.each { |l| puts l }
      exit
    when "--days"
      begin
        days_in_advance = Integer(arg)
        raise unless days_in_advance >= 0
      rescue
        raise "The argument for -d or --days must be a non-negative integer."
      end

    end

  end

rescue

  STDERR.print $!.to_s + "\n\n"
  usage
  exit

end

unless ARGV.length == 0
  STDERR.puts "Extraneous command line arguments: #{ARGV.join(' ')}"
end

unless days_in_advance
  days_in_advance = 7
end

def fudge_feb_29(year, month, day)
  # Just pretend that birthdays on the 29th of February in non-leap years
  # are on the 28th, for the purposes of deciding whether they're in
  # the next n days.
  is_leap_year = Date.new(year, 1, 1).leap?
  day = 28 if (day == 29) && (month == 2) && !is_leap_year
  Date.new(year, month, day)
end

def within_next_days( day, month, days )

  day = Integer(day.gsub(/^0/,''))
  month = Integer(month.gsub(/^0/,''))

  today = Date.today


  day_this_year = fudge_feb_29( today.year, month, day )
  day_next_year = fudge_feb_29( today.year + 1, month, day )

  for d in [ day_this_year, day_next_year ]

    difference = d - today
    if (difference >= 0) && (difference <= days)
      return difference.round
    end

  end

  return nil

end

class String

  def to_qp

    result = self.gsub( /=/m, '=3D' )

    result.gsub!( /([ \x09]+)\n/m ) { |m|
      m.gsub( /[ \x09]/ ) { |n|
        sprintf( '=%02X', n.unpack('C')[0] )
      }
    }

    result.gsub!( /[\x00-\x08\x09\x0b\x0d\x1f\x7f-\xff]/m ) { |m|
      sprintf( '=%02X', m.unpack('C')[0] )
    }

    result.gsub!( /(.?.?.?.{69}(=[^=]{2}|[^=]{3}))/ ) { |m|
      m + "=\n"
    }

    result

  end

end


just_people = Array.new
full_details = Array.new

open( filename ) do |f|

  f.each do |line|

    line.chomp!
    line.gsub!( /#.*$/, '' )

    next if line =~ /^\s*$/

    if line =~ birthday_line_re

      date = $1
      year = $2
      month = $3
      day = $4
      name = $5

      begin
        within = within_next_days( day, month, days_in_advance )
      rescue
        STDERR.puts "A date calculation failed; are you sure '#{date}'"
        STDERR.puts "is a valid date?"
      end

      if within

        just_people.push name
        all_details = name + "'s birthday is on: #{date}\n"
        if within == 0
          all_details += "   (that's today)\n"
        else
          all_details += "   (in #{within} day's time)\n"
        end
        if year != 'XXXX'
          if (day != 29) && (month != 2) # Because then it's more complicated...
            actual_birthday = (Date.today + within).year - Integer(year)
            all_details += "   (he/she will be #{(actual_birthday)})\n"
          end
        end
        full_details.push all_details

      end

    else
      STDERR.puts "This line is malformed: #{line}"
    end

  end

end

quoted_message = full_details.join("\n").to_qp

if mail_report_address && (full_details.length > 0)

  subject_line = "birthdays for: " + just_people.join(', ')

  command = [ '/sbin/exim',
    '-bm',
    '-i',
    mail_report_address ]

  Kernel.open( "|-", "w" ) do |f|
    if f
      f.puts "To: #{mail_report_address}"
      f.puts "From: Birthday Reminder <mark-birthdays@longair.net>"
      f.puts "Subject: #{subject_line}"
      f.puts "MIME-Version: 1.0"
      f.puts 'Content-Type: text/plain; charset=UTF-8'
      f.puts 'Content-Transfer-Encoding: quoted-printable'
      f.puts
      f.puts quoted_message
      f.puts
    else
      begin
        exec( *command )
      rescue
        raise "Couldn't exec #{command.join(' ')}: #{$!}\n"
      end
    end
  end

else

  full_details.each do |d|

    puts d
    puts

  end


end