Redmine

# redMine - project management software

# Copyright (C) 2006-2007  Jean-Philippe Lang

#

# This program is free software; you can redistribute it and/or

# modify it under the terms of the GNU General Public License

# as published by the Free Software Foundation; either version 2

# of the License, or (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

class MailHandler < ActionMailer::Base

  include ActionView::Helpers::SanitizeHelper

  include Redmine::I18n

  class UnauthorizedAction < StandardError; end

  class MissingInformation < StandardError; end

  attr_reader :email, :user

  def self.receive(email, options={})

    @@handler_options = options.dup

    @@handler_options[:issue] ||= {}

    @@handler_options[:allow_override] = @@handler_options[:allow_override].split(',').collect(&:strip) if @@handler_options[:allow_override].is_a?(String)

    @@handler_options[:allow_override] ||= []

    # Project needs to be overridable if not specified

    @@handler_options[:allow_override] << 'project' unless @@handler_options[:issue].has_key?(:project)

    # Status overridable by default

    @@handler_options[:allow_override] << 'status' unless @@handler_options[:issue].has_key?(:status)

    @@handler_options[:no_permission_check] = (@@handler_options[:no_permission_check].to_s == '1' ? true : false)

    super email

  end

  # Processes incoming emails

  # Returns the created object (eg. an issue, a message) or false

  def receive(email)

    @email = email

    sender_email = email.from.to_a.first.to_s.strip

    # Ignore emails received from the application emission address to avoid hell cycles

    if sender_email.downcase == Setting.mail_from.to_s.strip.downcase

      logger.info  "MailHandler: ignoring email from Redmine emission address [#{sender_email}]" if logger && logger.info

      return false

    end

    @user = User.find_by_mail(email.from.to_a.first.to_s.strip)

    if @user && !@user.active?

      logger.info  "MailHandler: ignoring email from non-active user [#{@user.login}]" if logger && logger.info

      return false

    end

    if @user.nil?

      # Email was submitted by an unknown user

      case @@handler_options[:unknown_user]

      when 'accept'

        @user = User.anonymous

      when 'create'

        @user = MailHandler.create_user_from_email(email)

        if @user

          logger.info "MailHandler: [#{@user.login}] account created" if logger && logger.info

          Mailer.deliver_account_information(@user, @user.password)

        else

          logger.error "MailHandler: could not create account for [#{email.from.first}]" if logger && logger.error

          return false

        end

      else

        # Default behaviour, emails from unknown users are ignored

        logger.info  "MailHandler: ignoring email from unknown user [#{email.from.first}]" if logger && logger.info

        return false

      end

    end

 User.current = @user

    dispatch

  end

  private

  MESSAGE_ID_RE = %r{^<redmine\.([a-z0-9_]+)\-(\d+)\.\d+@}

  ISSUE_REPLY_SUBJECT_RE = %r{\[[^\]]*#(\d+)\]}

  MESSAGE_REPLY_SUBJECT_RE = %r{\[[^\]]*msg(\d+)\]}

  def dispatch

    headers = [email.in_reply_to, email.references].flatten.compact

    if headers.detect {|h| h.to_s =~ MESSAGE_ID_RE}

      klass, object_id = $1, $2.to_i

      method_name = "receive_#{klass}_reply"

      if self.class.private_instance_methods.collect(&:to_s).include?(method_name)

        send method_name, object_id

      else

        # ignoring it

      end

    elsif m = email.subject.match(ISSUE_REPLY_SUBJECT_RE)

      receive_issue_reply(m[1].to_i)

    elsif m = email.subject.match(MESSAGE_REPLY_SUBJECT_RE)

      receive_message_reply(m[1].to_i)

    else

      dispatch_to_default

 end

  rescue ActiveRecord::RecordInvalid => e

    # TODO: send a email to the user

    logger.error e.message if logger

    false

  rescue MissingInformation => e

    logger.error "MailHandler: missing information from #{user}: #{e.message}" if logger

    false

  rescue UnauthorizedAction => e

    logger.error "MailHandler: unauthorized attempt from #{user}" if logger

    false

  end

  def dispatch_to_default

    receive_issue

  end

  # Creates a new issue

  def receive_issue

    project = target_project

    # check permission

    unless @@handler_options[:no_permission_check]

      raise UnauthorizedAction unless user.allowed_to?(:add_issues, project)

    end

    issue = Issue.new(:author => user, :project => project)

    issue.safe_attributes = issue_attributes_from_keywords(issue)

    issue.safe_attributes = {'custom_field_values' => custom_field_values_from_keywords(issue)}

    issue.subject = email.subject.to_s.chomp[0,255]

    if issue.subject.blank?

      issue.subject = '(no subject)'

    end

    issue.description = cleaned_up_text_body

    # add To and Cc as watchers before saving so the watchers can reply to Redmine

    add_watchers(issue)

    issue.save!

    add_attachments(issue)

    logger.info "MailHandler: issue ##{issue.id} created by #{user}" if logger && logger.info

    issue

  end

  # Adds a note to an existing issue

  def receive_issue_reply(issue_id)

    issue = Issue.find_by_id(issue_id)

    return unless issue

    # check permission

    unless @@handler_options[:no_permission_check]

      raise UnauthorizedAction unless user.allowed_to?(:add_issue_notes, issue.project) || user.allowed_to?(:edit_issues, issue.project)

    end

    # ignore CLI-supplied defaults for new issues

    @@handler_options[:issue].clear

    journal = issue.init_journal(user, cleaned_up_text_body)

    issue.safe_attributes = issue_attributes_from_keywords(issue)

    issue.safe_attributes = {'custom_field_values' => custom_field_values_from_keywords(issue)}

    add_attachments(issue)

    issue.save!

    logger.info "MailHandler: issue ##{issue.id} updated by #{user}" if logger && logger.info

    journal

  end

  # Reply will be added to the issue

  def receive_journal_reply(journal_id)

    journal = Journal.find_by_id(journal_id)

    if journal && journal.journalized_type == 'Issue'

      receive_issue_reply(journal.journalized_id)

    end

  end

  # Receives a reply to a forum message

  def receive_message_reply(message_id)

    message = Message.find_by_id(message_id)

    if message

      message = message.root

      unless @@handler_options[:no_permission_check]

        raise UnauthorizedAction unless user.allowed_to?(:add_messages, message.project)

      end

      if !message.locked?

        reply = Message.new(:subject => email.subject.gsub(%r{^.*msg\d+\]}, '').strip,

                            :content => cleaned_up_text_body)

        reply.author = user

        reply.board = message.board

        message.children << reply

        add_attachments(reply)

        reply

      else

        logger.info "MailHandler: ignoring reply from [#{sender_email}] to a locked topic" if logger && logger.info

      end

    end

  end

  def add_attachments(obj)

    if email.has_attachments?

      email.attachments.each do |attachment|

        Attachment.create(:container => obj,

                          :file => attachment,

                          :author => user,

                          :content_type => attachment.content_type)

      end

    end

  end

  # Adds To and Cc as watchers of the given object if the sender has the

  # appropriate permission

  def add_watchers(obj)

    if user.allowed_to?("add_#{obj.class.name.underscore}_watchers".to_sym, obj.project)

      addresses = [email.to, email.cc].flatten.compact.uniq.collect {|a| a.strip.downcase}

      unless addresses.empty?

        watchers = User.active.find(:all, :conditions => ['LOWER(mail) IN (?)', addresses])

        watchers.each {|w| obj.add_watcher(w)}

      end

    end

  end

  def get_keyword(attr, options={})

    @keywords ||= {}

    if @keywords.has_key?(attr)

      @keywords[attr]

    else

      @keywords[attr] = begin

        if (options[:override] || @@handler_options[:allow_override].include?(attr.to_s)) && (v = extract_keyword!(plain_text_body, attr, options[:format]))

          v

        elsif !@@handler_options[:issue][attr].blank?

          @@handler_options[:issue][attr]

        end

      end

    end

  end

  # Destructively extracts the value for +attr+ in +text+

  # Returns nil if no matching keyword found

  def extract_keyword!(text, attr, format=nil)

    keys = [attr.to_s.humanize]

    if attr.is_a?(Symbol)

      keys << l("field_#{attr}", :default => '', :locale =>  user.language) if user

      keys << l("field_#{attr}", :default => '', :locale =>  Setting.default_language)

    end

    keys.reject! {|k| k.blank?}

    keys.collect! {|k| Regexp.escape(k)}

    format ||= '.+'

    text.gsub!(/^(#{keys.join('|')})[ \t]*:[ \t]*(#{format})\s*$/i, '')

    $2 && $2.strip

  end

  def target_project

    # TODO: other ways to specify project:

    # * parse the email To field

    # * specific project (eg. Setting.mail_handler_target_project)

    target = Project.find_by_identifier(get_keyword(:project))

    raise MissingInformation.new('Unable to determine target project') if target.nil?

    target

  end

  # Returns a Hash of issue attributes extracted from keywords in the email body

  def issue_attributes_from_keywords(issue)

    assigned_to = (k = get_keyword(:assigned_to, :override => true)) && find_user_from_keyword(k)

    assigned_to = nil if assigned_to && !issue.assignable_users.include?(assigned_to)

    attrs = {

      'tracker_id' => (k = get_keyword(:tracker)) && issue.project.trackers.find_by_name(k).try(:id),

      'status_id' =>  (k = get_keyword(:status)) && IssueStatus.find_by_name(k).try(:id),

      'priority_id' => (k = get_keyword(:priority)) && IssuePriority.find_by_name(k).try(:id),

      'category_id' => (k = get_keyword(:category)) && issue.project.issue_categories.find_by_name(k).try(:id),

      'assigned_to_id' => assigned_to.try(:id),

      'fixed_version_id' => (k = get_keyword(:fixed_version, :override => true)) && issue.project.shared_versions.find_by_name(k).try(:id),

      'start_date' => get_keyword(:start_date, :override => true, :format => '\d{4}-\d{2}-\d{2}'),

      'due_date' => get_keyword(:due_date, :override => true, :format => '\d{4}-\d{2}-\d{2}'),

      'estimated_hours' => get_keyword(:estimated_hours, :override => true),

      'done_ratio' => get_keyword(:done_ratio, :override => true, :format => '(\d|10)?0')

    }.delete_if {|k, v| v.blank? }

    if issue.new_record? && attrs['tracker_id'].nil?

      attrs['tracker_id'] = issue.project.trackers.find(:first).try(:id)

    end

    attrs

  end

  # Returns a Hash of issue custom field values extracted from keywords in the email body

  def custom_field_values_from_keywords(customized)

    customized.custom_field_values.inject({}) do |h, v|

      if value = get_keyword(v.custom_field.name, :override => true)

        h[v.custom_field.id.to_s] = value

      end

      h

    end

  end

  # Returns the text/plain part of the email

  # If not found (eg. HTML-only email), returns the body with tags removed

  def plain_text_body

    return @plain_text_body unless @plain_text_body.nil?

    parts = @email.parts.collect {|c| (c.respond_to?(:parts) && !c.parts.empty?) ? c.parts : c}.flatten

    if parts.empty?

      parts << @email

    end

    plain_text_part = parts.detect {|p| p.content_type == 'text/plain'}

    if plain_text_part.nil?

      # no text/plain part found, assuming html-only email

      # strip html tags and remove doctype directive

      @plain_text_body = strip_tags(@email.body.to_s)

      @plain_text_body.gsub! %r{^<!DOCTYPE .*$}, ''

    else

      @plain_text_body = plain_text_part.body.to_s

	      end

    @plain_text_body.strip!

    @plain_text_body

  end

  def cleaned_up_text_body

    cleanup_body(plain_text_body)

  end

  def self.full_sanitizer

    @full_sanitizer ||= HTML::FullSanitizer.new

  end

# Creates a user account for the +email+ sender

  def self.create_user_from_email(email)

    addr = email.from_addrs.to_a.first

    if addr && !addr.spec.blank?

      user = User.new

      user.mail = addr.spec

      names = addr.name.blank? ? addr.spec.gsub(/@.*$/, '').split('.') : addr.name.split

      user.firstname = names.shift

      user.lastname = names.join(' ')

      user.lastname = '-' if user.lastname.blank?

      user.login = user.mail

      user.password = ActiveSupport::SecureRandom.hex(5)

      user.language = Setting.default_language

      user.save ? user : nil

    end

  end

  private

  # Removes the email body of text after the truncation configurations.

  def cleanup_body(body)

    delimiters = Setting.mail_handler_body_delimiters.to_s.split(/[\r\n]+/).reject(&:blank?).map {|s| Regexp.escape(s)}

    unless delimiters.empty?

      regex = Regexp.new("^[> ]*(#{ delimiters.join('|') })\s*[\r\n].*", Regexp::MULTILINE)

      body = body.gsub(regex, '')

    end

    body.strip

  end

  def find_user_from_keyword(keyword)

    user ||= User.find_by_mail(keyword)

    user ||= User.find_by_login(keyword)

    if user.nil? && keyword.match(/ /)

      firstname, lastname = *(keyword.split) # "First Last Throwaway"

      user ||= User.find_by_firstname_and_lastname(firstname, lastname)

    end

    user

  end

end