# Redmine - project management software
# Copyright (C) 2006-2017  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 TimeEntry < ActiveRecord::Base
  include Redmine::SafeAttributes
  # could have used polymorphic association
  # project association here allows easy loading of time entries at project level with one database trip
  belongs_to :project
  belongs_to :issue
  belongs_to :user
  belongs_to :author, :class_name => 'User'
  belongs_to :activity, :class_name => 'TimeEntryActivity'

  acts_as_customizable
  acts_as_event :title => Proc.new { |o|
                  related   = o.issue if o.issue && o.issue.visible?
                  related ||= o.project
                  "#{l_hours(o.hours)} (#{related.event_title})"
                },
                :url => Proc.new {|o| {:controller => 'timelog', :action => 'index', :project_id => o.project, :issue_id => o.issue}},
                :author => :user,
                :group => :issue,
                :description => :comments

  acts_as_activity_provider :timestamp => "#{table_name}.created_on",
                            :author_key => :user_id,
                            :scope => joins(:project).preload(:project)

  validates_presence_of :author_id, :user_id, :activity_id, :project_id, :hours, :spent_on
  validates_presence_of :issue_id, :if => lambda { Setting.timelog_required_fields.include?('issue_id') }
  validates_presence_of :comments, :if => lambda { Setting.timelog_required_fields.include?('comments') }
  validates_numericality_of :hours, :allow_nil => true, :message => :invalid
  validates_length_of :comments, :maximum => 1024, :allow_nil => true
  validates :spent_on, :date => true
  before_validation :set_project_if_nil
  before_validation :set_author_if_nil
  validate :validate_time_entry

  scope :visible, lambda {|*args|
    joins(:project).
    where(TimeEntry.visible_condition(args.shift || User.current, *args))
  }
  scope :left_join_issue, lambda {
    joins("LEFT OUTER JOIN #{Issue.table_name} ON #{Issue.table_name}.id = #{TimeEntry.table_name}.issue_id")
  }
  scope :on_issue, lambda {|issue|
    joins(:issue).
    where("#{Issue.table_name}.root_id = #{issue.root_id} AND #{Issue.table_name}.lft >= #{issue.lft} AND #{Issue.table_name}.rgt <= #{issue.rgt}")
  }

  safe_attributes 'user_id', 'hours', 'comments', 'project_id', 'issue_id', 'activity_id', 'spent_on', 'custom_field_values', 'custom_fields'

  # Returns a SQL conditions string used to find all time entries visible by the specified user
  def self.visible_condition(user, options={})
    Project.allowed_to_condition(user, :view_time_entries, options) do |role, user|
      if role.time_entries_visibility == 'all'
        nil
      elsif role.time_entries_visibility == 'own' && user.id && user.logged?
        "#{table_name}.user_id = #{user.id}"
      else
        '1=0'
      end
    end
  end

  # Returns true if user or current user is allowed to view the time entry
  def visible?(user=nil)
    (user || User.current).allowed_to?(:view_time_entries, self.project) do |role, user|
      if role.time_entries_visibility == 'all'
        true
      elsif role.time_entries_visibility == 'own'
        self.user == user
      else
        false
      end
    end
  end

  def initialize(attributes=nil, *args)
    super
    if new_record? && self.activity.nil?
      if default_activity = TimeEntryActivity.default
        self.activity_id = default_activity.id
      end
      self.hours = nil if hours == 0
    end
  end

  def safe_attributes=(attrs, user=User.current)
    if attrs
      attrs = super(attrs)
      if issue_id_changed? && issue
        if issue.visible?(user) && user.allowed_to?(:log_time, issue.project)
          if attrs[:project_id].blank? && issue.project_id != project_id
            self.project_id = issue.project_id
          end
          @invalid_issue_id = nil
        else
          @invalid_issue_id = issue_id
        end
      end
    end
    attrs
  end

  def set_project_if_nil
    self.project = issue.project if issue && project.nil?
  end

  def set_author_if_nil
    self.author = User.current if author.nil?
  end

  def validate_time_entry
    if hours
      errors.add :hours, :invalid if hours < 0
      errors.add :hours, :invalid if hours == 0.0 && hours_changed? && !Setting.timelog_accept_0_hours?

      max_hours = Setting.timelog_max_hours_per_day.to_f
      if hours_changed? && max_hours > 0.0
        logged_hours = other_hours_with_same_user_and_day
        if logged_hours + hours > max_hours
          errors.add :base, I18n.t(:error_exceeds_maximum_hours_per_day,
            :logged_hours => format_hours(logged_hours), :max_hours => format_hours(max_hours))
        end
      end
    end
    errors.add :project_id, :invalid if project.nil?
    errors.add :user_id, :invalid if (user_id != author_id && !self.assignable_users.map(&:id).include?(user_id))
    errors.add :issue_id, :invalid if (issue_id && !issue) || (issue && project!=issue.project) || @invalid_issue_id
    errors.add :activity_id, :inclusion if activity_id_changed? && project && !project.activities.include?(activity)
    if spent_on_changed? && user
      errors.add :base, I18n.t(:error_spent_on_future_date) if (!Setting.timelog_accept_future_dates? && (spent_on > user.today))
    end
  end

  def hours=(h)
    write_attribute :hours, (h.is_a?(String) ? (h.to_hours || h) : h)
  end

  def hours
    h = read_attribute(:hours)
    if h.is_a?(Float)
      h.round(2)
    else
      h
    end
  end

  # tyear, tmonth, tweek assigned where setting spent_on attributes
  # these attributes make time aggregations easier
  def spent_on=(date)
    super
    self.tyear = spent_on ? spent_on.year : nil
    self.tmonth = spent_on ? spent_on.month : nil
    self.tweek = spent_on ? Date.civil(spent_on.year, spent_on.month, spent_on.day).cweek : nil
  end

  # Returns true if the time entry can be edited by usr, otherwise false
  def editable_by?(usr)
    visible?(usr) && (
      (usr == user && usr.allowed_to?(:edit_own_time_entries, project)) || usr.allowed_to?(:edit_time_entries, project)
    )
  end

  # Returns the custom_field_values that can be edited by the given user
  def editable_custom_field_values(user=nil)
    visible_custom_field_values
  end

  # Returns the custom fields that can be edited by the given user
  def editable_custom_fields(user=nil)
    editable_custom_field_values(user).map(&:custom_field).uniq
  end

  def assignable_users
    users = []
    if project
      users = project.members.active.preload(:user)
      users = users.map(&:user).select{ |u| u.allowed_to?(:log_time, project) }
    end
    users << User.current if User.current.logged? && !users.include?(User.current)
    users
  end

  private

  # Returns the hours that were logged in other time entries for the same user and the same day
  def other_hours_with_same_user_and_day
    if user_id && spent_on
      TimeEntry.
        where(:user_id => user_id, :spent_on => spent_on).
        where.not(:id => id).
        sum(:hours).to_f
    else
      0.0
    end
  end
end