invoice.rb

# -*- encoding : utf-8 -*-
class Invoice < ActiveRecord::Base
  paginates_per 15

  belongs_to :campaign
  has_and_belongs_to_many :tasks
  has_many :expense_notes

  validates_presence_of :campaign
  validates_presence_of :start_date
  validates_presence_of :end_date
  validates_presence_of :expiration_period

  validate :validate_end_date
  validate :invalid_invoice_period
  validate :intersecting_invoices
  validate :presence_of_non_invoiced_good_hours_in_some_task

  before_validation :set_start_date_if_blank
  after_create :invoice_tasks
  after_create :invoice_expense_notes

  def tasks_hours
    tasks.inject(0) do |hours, task|
      hours + task.total_good_hours_in_period(:do_not_invoice, start_date, end_date)
    end
  end

  def tasks_amount
    invoiced_hours * campaign.try(:hourly_price)
  end

  def expense_notes_amount
    expense_notes.inject(0) do |amount, expense_note|
      amount + expense_note.amount
    end
  end

  def amount
    tasks_amount + expense_notes_amount
  end

  private

  ######### BEFORE VALIDATION #########

  def set_start_date_if_blank
    if start_date.blank?
      self.start_date = if campaign.invoices.blank?
        campaign.activities.minimum(:estimated_start_date)
      else
        campaign.invoices.maximum(:end_date).advance(:days => 1)
      end
    end
  end

  ######### VALIDAZIONI ###########

  def presence_of_non_invoiced_good_hours_in_some_task
     # perche possa creare una fattura
     if campaign.present?
       # almeno uno tra i task della campagna
       campaign.activities.map(&:tasks).flatten.any? do |task|
         # deve avere qualche ora da fatturare nel periodo della fattura stessa
         task.total_good_hours_in_period(:do_not_invoice, start_date, end_date).nonzero?
       end
     end
   end

   def validate_end_date
     # la data di inizio fattura dev'essere precedente a quella di fine
     if start_date.present? && end_date.present? && end_date < start_date
       errors.add :end_date, I18n.t("activerecord.errors.models.contract.attributes.end_date.lower_than_start_date")
     end
   end

   def invalid_invoice_period
     if end_date.present? && start_date.present? && campaign.present? && campaign.activities.present?
       # la data di inizio fattura dev'essere superiore alla data di inizio campagna
       if start_date < campaign.activities.minimum(:estimated_start_date)
         errors.add :start_date, I18n.t("activerecord.errors.models.invoice.attributes.start_date.lower_than_campaign_start")
       # la data di termine fattura dev'essere inferiore o uguale alla fine campagna
       elsif end_date > campaign.activities.maximum(:estimated_end_date)
         errors.add :end_date, I18n.t("activerecord.errors.models.invoice.attributes.end_date.greater_than_campaign_end")
       end
     end
   end

   def intersecting_invoices
     # non posso avere due fatture con periodo di appartenenza intersecante
     if start_date.present? && campaign.present? && campaign.invoices.present? && start_date <= (campaign.invoices - self).max(:end_date)
       errors.add :end_date, I18n.t("activerecord.errors.models.invoice.attributes.end_date.lower_than_previous")
     end
   end

  ########## AFTER CREATE ###########

  def invoice_tasks
    campaign.activities.map(&:tasks).flatten.each do |task|
      if task.total_good_hours_in_period(:do_not_invoice, start_date, end_date).nonzero?
        task.invoices << self
      end
    end
  end

  def invoice_expense_notes
    campaign.activities.map(&:expense_notes).each do |expense_note|
      if expense_note.spending_date <= end_date && expense_note.spending_date >= start_date
        self.expense_notes << expense_note
      end
    end
  end

end