# encoding: utf-8

#--

#   Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies)

#   Copyright (C) 2008 Johan Sørensen <johan@johansorensen.com>

#   Copyright (C) 2008 David A. Cuadrado <krawek@gmail.com>

#   Copyright (C) 2008 Tor Arne Vestbø <tavestbo@trolltech.com>

#

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

#   it under the terms of the GNU Affero General Public License as published by

#   the Free Software Foundation, either version 3 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 Affero General Public License for more details.

#

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

#   along with this program.  If not, see <http://www.gnu.org/licenses/>.

#++

class Comment < ActiveRecord::Base

  include Gitorious::Search

  belongs_to :user

  belongs_to :target, :polymorphic => true

  belongs_to :project

  has_many   :events, :as => :target, :dependent => :destroy

  after_create :notify_target_if_supported

  after_create :update_state_in_target

  serialize :state_change, Array

  is_indexed do |s|

    s.index :body

    s.index "user#login", :as => :commented_by

  end

  attr_protected :user_id

  validates_presence_of :user_id, :target, :project_id

  validates_presence_of :body, :if =>  Proc.new {|mr| mr.body_required?}

  named_scope :with_shas, proc{|*shas|

    {:conditions => { :sha1 => shas.flatten }, :include => :user}

  }

  NOTIFICATION_TARGETS = [ MergeRequest, MergeRequestVersion ]

  def deliver_notification_to(another_user)

    message_body = "#{user.title} commented:\n\n#{body}"

    if [MergeRequest, MergeRequestVersion].include?(target.class)

      if state_change

        message_body << "\n\nThe status of your merge request"

        message_body << " is now #{state_changed_to}"

      end

      subject_class_name = "merge request"

    else

      subject_class_name = target.class.human_name.downcase

    end

    message = Message.new({

      :sender => self.user,

      :recipient => another_user,

      :subject => "#{user.title} commented on your #{subject_class_name}",

      :body => message_body,

      :notifiable => self.target,

    })

    message.save

  end

  def state=(new_state)

    return if new_state.blank?

    result = []

    if applies_to_merge_request?

      return if target.status_tag.to_s == new_state

      result << (target.status_tag.nil? ? nil : target.status_tag.name)

    end

    result << new_state

    self.state_change = result

  end

  def state_changed_to

    state_change.to_a.last

  end

  def state_changed_from

    state_change.to_a.size > 1 ? state_change.first : nil

  end

  def body_required?

    if applies_to_merge_request?

      return state_change.blank?

    else

      return true

    end

  end

  # +lines_str+ is a representation of the first and last line-number

  # tuple (as generated by Diff::Unified::Generator) and the lines the

  # comment span, in the follow format:

  # first_tuple:last_tuple+line_span

  def lines=(lines_str)

    start, rest = lines_str.split(":")

    raise "invalid lines format" if rest.blank?

    last, amount = rest.split("+")

    if start.blank? || last.blank? || amount.blank?

      raise "invalid lines format"

    end

    self.first_line_number = start

    self.last_line_number = last

    self.number_of_lines = amount

  end

  def lines

    "#{self.first_line_number}:#{self.last_line_number}+#{self.number_of_lines}"

  end

  def sha_range

    first, last = sha1.split("-")

    first..(last||first)

  end

  def applies_to_line_numbers?

    return !first_line_number.blank?

  end

  def applies_to_merge_request?

    MergeRequest === target

  end

  def editable_by?(a_user)

    creator?(a_user) && recently_created?

  end

  def creator?(a_user)

    a_user == user

  end

  def recently_created?

    created_at > 10.minutes.ago

  end

  protected

    def notify_target_if_supported

      if target && NOTIFICATION_TARGETS.include?(target.class)

        if self.target === MergeRequestVersion

          target_user = target.merge_request.user

        else

          target_user = target.user

        end

        return if target_user == user

        deliver_notification_to(target_user)

      end

    end

    def update_state_in_target

      if applies_to_merge_request? and state_change

        target.with_user(user) do

          if target.resolvable_by?(user)

            target.status_tag=(state_changed_to)

            target.create_status_change_event(body)

          end

        end

      end

    end

end