Code for Caren's auto responder and signature cutoff rules. Based on BodyParts

bodyparts.rb

require 'mail'
require 'tmail'

class BodyParts
  def self.rules
     [
       # Dutch signatures
       { :server => 'Signature #1', :reply_delimiter => /^\r\nMet vriendelijke groet./m },
       { :server => 'Signature #2', :reply_delimiter => /^\r\nGroet./m },
       { :server => 'Signature #3', :reply_delimiter => /^\r\nmvg./m },

       # English signatures
       { :server => 'Signature #1', :reply_delimiter => /^\r\nKind regards./m },
       { :server => 'Signature #1', :reply_delimiter => /^\r\nRegards./m },

       # Dutch rules
       { :server => 'Mail.app', :reply_delimiter => /^Op.*?geschreven:.$/m },
       { :server => 'Gmail', :reply_delimiter => /^Op.*?schreef:.$/m },
       { :server => 'Outlook Express/AOL Webmail', :reply_delimiter =>  /^-+.*Oorspronkelijk bericht.*-+/ },

       # English rules
       { :server => 'Gmail', :reply_delimiter => /^On.*?wrote:.$/m },
       { :server => 'Gmail #2', :reply_delimiter => /^\d+\/\d+\/\d+.*<.*>:.$/m },
       { :server => 'Yahoo! Mail', :reply_delimiter => /^_+\r\nFrom:/ },
       { :server => 'Microsoft Live Mail/Hotmail', :reply_delimiter =>  /\r\n\r\n(Date|Subject):/ },
       { :server => 'Outlook Express/AOL Webmail', :reply_delimiter =>  /^-+.*Original Message.*-+/ },

       # Fallbacks
       { :server => 'Fallback #1', :reply_delimiter =>  /^_+/ },
       { :server => 'Fallback #2', :reply_delimiter =>  /^\>./ }
     ]
  end

  def self.auto_responder_rules
    [
      # Dutch auto-responder subjects
      /^Niet aanwezig/,
      /^Automatisch/,
      /^Afwezigheidsmelding/,

      # English auto-responder subjects
      /^Out of Office/,
      /^I'm currently out of office/
    ]
  end

  def self.extract_tmail_attributes(tmail_object)
    if mail_encoding = tmail_object['content_transfer_encoding']
      content_encoding = mail_encoding.to_s.downcase
    else
      content_encoding = "not known"
    end

    body = if tmail_object.multipart?
      tmail_object.parts.first.body
    else
      tmail_object.body
    end

    {:content_encoding => content_encoding, :body => body}
  end

  def self.extract_mail_attributes(mail_object)
    if plain_part = mail_object.find_first_mime_type('text/plain')
      part = plain_part
    else
      part = mail_object
    end

    if mail_encoding = part['content_transfer_encoding'] || mail_encoding = mail_object['content_transfer_encoding']
      content_encoding = mail_encoding.encoding
    else
      content_encoding = "not known"
    end

    {:content_encoding => content_encoding, :body => part.body.raw_source}
  end

  def self.auto_responder?(email)
    email = Mail::Message.new(email) if email.is_a? String

    if email.header["X-Auto-Response-Suppress"] ||
       (email.header["Auto-Submitted"] && email.header["Auto-Submitted"].value != "no") ||
       auto_responder_rules.map{ |rule| email.subject ? email.subject.match(rule) : nil }.compact.present?
       return true
     end

    return false
  end

  def self.find_reply_in(email)
    email = Mail::Message.new(email) if email.is_a? String

    mail_attributes = case email.class.to_s
      when "TMail::Mail" then extract_tmail_attributes(email)
      when "Mail::Message" then extract_mail_attributes(email)
      else raise "You must pass in either a TMail or Mail object or raw email source text"
    end

    raw_body = mail_attributes[:body]
    body = case mail_attributes[:content_encoding]
      when "base64" then Base64.decode64 raw_body
      when "quoted-printable" then Mail::Encodings::QuotedPrintable.decode raw_body
      else raw_body
    end

    matches = rules.map {|rule| body.match(rule[:reply_delimiter])}.compact!

    unless matches.empty?
      match = matches.sort_by {|m| m.begin(0)}.first
      new_message = body[0, match.begin(0)]
      {:new_message => new_message.strip, :rest_of_thread => body[match.begin(0)..-1].strip}
    else
      {:new_message => body, :rest_of_thread => nil}
    end
  end
end