#-- copyright
# OpenProject is a project management system.
# Copyright (C) 2012-2015 the OpenProject Foundation (OPF)
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License version 3.
#
# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
# Copyright (C) 2006-2013 Jean-Philippe Lang
# Copyright (C) 2010-2013 the ChiliProject Team
#
# 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.
#
# See doc/COPYRIGHT.rdoc for more details.
#++

module UserInvitation
  EVENT_NAME = 'user_invited'

  module_function

  ##
  # Creates an invited user with the given email address.
  # If no first and last is given it will default to 'OpenProject User'
  # for the first name and 'To-be' for the last name.
  # The default login is the email address.
  #
  # @param email E-Mail address the invitation is sent to.
  # @param login User's login (optional)
  # @param first_name The user's first name (optional)
  # @param last_name The user's last name (optional)
  #
  # @yield [user] Allows modifying the created user before saving it.
  #
  # @return The invited user. If the invitation failed, calling `#registered?`
  #         on the returned user will yield `false`. Check for validation errors
  #         in that case.
  def invite_new_user(email:, login: nil, first_name: nil, last_name: nil)
    user = User.new login: login || email,
                    mail: email,
                    firstname: first_name || email,
                    lastname: last_name || '(invited)',
                    status: Principal::STATUSES[:invited]

    yield user if block_given?

    invite_user! user
  end

  ##
  # Invites the given user. An email will be sent to their email address
  # containing the token necessary for the user to register.
  #
  # Validates and saves the given user. The invitation will fail if the user is invalid.
  #
  # @return The invited user or nil if the invitation failed.
  def invite_user!(user)
    user, token = user_invitation user

    if token
      OpenProject::Notifications.send(EVENT_NAME, token)

      user
    end
  end

  ##
  # Creates an invited user with the given email address.
  # If no first and last is given it will default to 'OpenProject User'
  # for the first name and 'To-be' for the last name.
  # The default login is the email address.
  #
  # @return Returns the user and the invitation token required to register.
  def user_invitation(user)
    User.transaction do
      user.invite

      if user.valid?
        token = invitation_token user
        token.save!

        user.save!

        return [user, token]
      end
    end

    [user, nil]
  end

  def token_action
    'invite'
  end

  def invitation_token(user)
    Token.find_or_initialize_by user: user, action: token_action
  end
end