refactor RentNumberValidator

app/models/rent.rb

@@ -53,5 +53,9 @@ def self.users_filter(params, id)
  def item
  Item.unscoped { super }
  end
+
+ def days
+ (self.begin.to_date.. self.end.to_date).to_a
+ end
 end
 

app/validators/rent_number_validator.rb

@@ -1,24 +1,43 @@
+# Validators are instantiated once, instance variables persist between validations, might cause bugs
 class RentNumberValidator < ActiveModel::Validator
- def validate(record)
- #Rent.where("begin < ? && end > ?", record.end, record.begin).where.not(state: :unprocessed).sum(:number)
- return if record.number.nil? || record.begin.nil? || record.end.nil?
- sum = 0
- rents = Rent.all
- rents.each do |rent|
- sum += rent.number if(rent.begin < record.end && rent.end > record.begin && rent.state != "unprocessed")
- end
- if sum+record.number > record.item.number
- record.errors.add :base, "Erre az időpontra sajnos nincs elég a kívánt eszközből."
- record.errors.add :base, "A megadott napokra elérhető eszközök száma:"
- day = record.begin.to_date
- while(day <= record.end.to_date)
- sum = 0
- rents.each do |rent|
- sum += rent.number if(rent.begin.to_date <= day && rent.end.to_date >= day && rent.state != "unprocessed")
- end
- record.errors.add :base, day.to_s + ": " + (record.item.number - sum).to_s + " darab"
- day += 1
- end
- end
+ def validate(record)
+ item = record.item
+ active_rents = active_rents(record)
+ rent_days = rent_days(active_rents)
+ rents_by_item = rents_by_item(rent_days, active_rents)
+
+ record.days.each do |day|
+ rent_number_for_day = rents_by_item.dig(day, item) || 0
+ if rent_number_for_day + record.number > item.number
+ available_item_number = item.number = rent_number_for_day
+ record.errors.add :base, "A kiválasztott napon(#{day}) csak #{available_item_number} darab #{item.name} elérhető."
+ end
  end
+ end
+
+ private
+
+ # hash[rent_day][item] = sum taken out amount item (per day, per item)
+ def rents_by_item(rent_days, active_rents)
+ result = {}
+ rent_days.each do |rent_date|
+ result[rent_date] = {} if result[rent_date].nil?
+ active_rents.each do |active_rent|
+ result[rent_date][active_rent.item] = 0 if result[rent_date][active_rent.item].nil?
+ result[rent_date][active_rent.item] += active_rent.number
+ end
+ end
+ result
+ end
+
+ def rent_days(active_rents)
+ active_rents.map(&:days).flatten.uniq.sort
+ end
+
+ def active_rents(record)
+ Rent.includes(:item)
+ .where(state: [:approved, :taken])
+ .where.not('rents.end <= :begin or :end <= rents.begin',
+ { begin: record.begin, end: record.end })
+ end
 end

spec/models/rent_spec.rb

@@ -2,7 +2,7 @@
 
 RSpec.describe Rent, type: :model do
  let(:user) { create(:user) }
- let(:item) { create(:item) }
+ let(:item) { create(:item, number: 10) }
  let(:pre_existing_rent) do
  Rent.create!(state: :approved, item: item, user: user,
  begin: DateTime.new(2022, 1, 10),
@@ -13,7 +13,7 @@
  Rent.new(state: :approved, item: item, user: user,
  begin: begin_date,
  end: end_date,
- number: 5)
+ number: rent_number)
  end
 
  subject do
@@ -29,34 +29,58 @@
  Timecop.return
  end
 
- context 'when the rent starts before the pre existing rent' do
- let(:begin_date) { DateTime.new(2022, 1, 5) }
- context 'and ends before the current rent' do
- let(:end_date) { DateTime.new(2022, 1, 9) }
- it { expect(subject).to be_valid }
+ context 'when the rent number equals to all available item number' do
+ let(:rent_number) { 10 }
+ context 'when the rent starts before the pre existing rent' do
+ let(:begin_date) { DateTime.new(2022, 1, 5) }
+ context 'and ends before the current rent' do
+ let(:end_date) { DateTime.new(2022, 1, 9) }
+ it { expect(subject).to be_valid }
+ end
+ context 'and ends on the current rent beginning date' do
+ let(:end_date) { DateTime.new(2022, 1, 10) }
+ it { expect(subject).to be_valid }
+ end
+ context 'and ends after the current_rent is take' do
+ let(:end_date) { DateTime.new(2022, 1, 11) }
+ it {
+ expect(subject).not_to be_valid
+ }
+ end
  end
- context 'and ends on the current rent beginning date' do
- let(:end_date) { DateTime.new(2022, 1, 10) }
- it { expect(subject).to be_valid }
+
+ context 'when the rent ends after the pre existing rent' do
+ let(:end_date) { DateTime.new(2022, 1, 20) }
+ context 'and begins before the current rent is back' do
+ let(:begin_date) { DateTime.new(2022, 1, 14) }
+ it { expect(subject).not_to be_valid }
+ end
+ context 'and begins whe the current rent is back' do
+ let(:begin_date) { DateTime.new(2022, 1, 15) }
+ it { expect(subject).to be_valid }
+ end
+ context 'and begins after the current rent is back' do
+ let(:begin_date) { DateTime.new(2022, 1, 16) }
+ it { expect(subject).to be_valid }
+ end
  end
- context 'and ends after the current_rent is take' do
- let(:end_date) { DateTime.new(2022, 1, 11) }
+ context 'and begins and ends during the current rent' do
+ let(:begin_date) { DateTime.new(2022, 1, 11) }
+ let(:end_date) { DateTime.new(2022, 1, 14) }
  it { expect(subject).not_to be_valid }
  end
- end
-
- context 'when the rent ends after the pre existing rent' do
- let(:end_date) { DateTime.new(2022, 1, 20) }
- context 'and begins before the current rent is back' do
- let(:begin_date) { DateTime.new(2022, 1, 14) }
+ context 'and begins and ends at the same time as the current rent' do
+ let(:begin_date) { DateTime.new(2022, 1, 10) }
+ let(:end_date) { DateTime.new(2022, 1, 15) }
  it { expect(subject).not_to be_valid }
  end
- context 'and begins whe the current rent is back' do
- let(:begin_date) { DateTime.new(2022, 1, 15) }
- it { expect(subject).to be_valid }
- end
- context 'and begins after the current rent is back' do
- let(:begin_date) { DateTime.new(2022, 1, 16) }
+ end
+
+ context 'when the rent number is less then all available item number' do
+ let(:rent_number) { 1 }
+ context 'and begins and ends at the same time as the current rent' do
+ let(:begin_date) { DateTime.new(2022, 1, 10) }
+ let(:end_date) { DateTime.new(2022, 1, 15) }
  it { expect(subject).to be_valid }
  end
  end