crmis/weddings

module Bookable
  extend ActiveSupport::Concern

  included do

    validates :start_time, presence: true
    validates :length, presence: true, numericality: {greater_than: 0}
    validate :start_date_cannot_be_in_the_past
    validate :overlaps

    before_validation :calculate_end_time


    scope :time_constraint, ->(c1, f1, c2, f2) do
      return nil unless f1 && f2
      where "%s ? AND %s ?" % [c1, c2], f1, f2
    end

    scope :end_during, ->(start_time, end_time) { time_constraint "end_time >", start_time, "end_time <", end_time }
    scope :start_during, ->(start_time, end_time) { time_constraint "start_time >", start_time, "start_time <", end_time }
    scope :happening_during, ->(start_time, end_time) { time_constraint "start_time >", start_time, "end_time <", end_time }
    scope :enveloping, ->(start_time, end_time) { time_constraint "start_time <", start_time, "end_time >", end_time }
    scope :identical, ->(start_time, end_time) { time_constraint "start_time =", start_time, "end_time =", end_time }

  end

  def overlaps
    overlapping_bookings = [
      room.bookings.end_during(start_time, end_time),
      room.bookings.start_during(start_time, end_time),
      room.bookings.happening_during(start_time, end_time),
      room.bookings.enveloping(start_time, end_time),
      room.bookings.identical(start_time, end_time)
    ].flatten

    overlapping_bookings.delete self
    if overlapping_bookings.any?
      errors.add(:base, 'Slot has already been booked')
    end
  end

  def start_date_cannot_be_in_the_past
    if start_time && start_time < DateTime.now + (15.minutes)
      errors.add(:start_time, 'must be at least 15 minutes from present time')
    end
  end

  def calculate_end_time
    start_time = validate_start_time
    length = validate_length
    if start_time && length
      self.end_time = start_time + (length.hours - 60)
    end
  end


  def as_json(options = {})
    {
      :id => self.id,
      :start => self.start_time,
      :end => self.end_time + 60,
      :recurring => false,
      :allDay => false
    }
  end

  private

  def validate_start_time
    if !self.start_time.nil?
      start_time = self.start_time
    else
      return nil
    end
  end

  def validate_length
    if !self.length.nil?
      length = self.length.to_i
    else
      return nil
    end
  end

end