class Timesheet < ActiveRecord::Base
  attr_accessible :status, :user_id, :start_date, :end_date, :activities_attributes
  
  SUBMITTED = 'Submitted'
  APPROUVED = 'Approuved'
  REJECTED = 'Rejected'
  
  STATUS_VALUES = [SUBMITTED, APPROUVED, REJECTED]
  belongs_to :user
  has_many :activities, dependent: :destroy, inverse_of: :timesheet
  has_many :time_entries, through: :activities
  accepts_nested_attributes_for :activities, allow_destroy: true
  
  validates :user_id, presence: true
  validates :status, presence: true, inclusion: {in: STATUS_VALUES}  
  validate :maximum_worktime_per_day
  
  after_update :check_an_activity_present
  
  after_initialize :init_working_week
  
  def date_range
    (start_date..end_date).to_a
  end

  def total_worked_time
    days = 0
    days = time_entries.sum(:worktime) unless time_entries.empty? 
    days   
  end

  def create_activity_days(activity)
    date_range.each { |date| activity.time_entries.build(workdate: date) }    
  end   
  
  def build_and_sort_time_entries
    entries = []
    activities.each do |activity|
      date_range.each do |week_day|
        activity.time_entries.build(workdate: week_day) unless activity.worked_days.include?(week_day)
      end
      
      entries = activity.time_entries
      entries.sort! { |a, b| a.workdate <=> b.workdate }      
    end
    entries
  end 

  
  private
  
  def init_working_week
    if start_date.blank? || end_date.blank?
      set_start_and_end_dates
    end
  end

  def set_start_and_end_dates
    filter_date = Date.today
    last_timesheet = Timesheet.last
    filter_date = last_timesheet.start_date.next_week if last_timesheet
    self.start_date = filter_date.beginning_of_week
    self.end_date = filter_date.end_of_week
  end
  
  def check_an_activity_present      
    raise "You should have at least ONE activity present" if activities.empty?
  end
  
  def maximum_worktime_per_day
    time_entries_by_date = time_entries.group_by(&:workdate)
    time_entries_by_date.each do |key, value|
      errors[:base] << "Maximum daily time should not exceed 1 day" if worktime_by_date(value) > 1
      break
    end
  end
  
  def worktime_by_date(daily_entries)
    time = 0      
    time = daily_entries.map(&:worktime).inject(:+) unless daily_entries.empty?
    time
  end
end