OOP school library: preserve data

app.rb

@@ -7,15 +7,18 @@
 
 require_relative 'modules/book_mod'
 require_relative 'modules/people_mod'
-require_relative 'modules/Rental_mod'
+require_relative 'modules/rental_mod'
+
+require_relative 'modules/save_data'
+require_relative 'modules/read_data'
 
 class App
   attr_accessor :books, :rentals, :people
 
   def initialize
-    @books = []
-    @rentals = []
-    @people = []
+    @books = ReadData.new.read_books
+    @people = ReadData.new.read_people
+    @rentals = ReadData.new.read_rentals(ReadData.new.read_books, ReadData.new.read_people)
   end
 
   include BookMod

data/books.json

@@ -0,0 +1,6 @@
+[
+  {
+    "title": "Grief child",
+    "author": "George"
+  }
+]

data/people.json

@@ -0,0 +1,30 @@
+[
+  {
+    "id": 630,
+    "name": "Amen",
+    "age": "20",
+    "type": "Student",
+    "parent_permission": true
+  },
+  {
+    "id": 204,
+    "name": "Shafu",
+    "age": "30",
+    "type": "Teacher",
+    "specialization": null
+  },
+  {
+    "id": 163,
+    "name": "shafiu",
+    "age": "10 ",
+    "type": "Student",
+    "parent_permission": true
+  },
+  {
+    "id": 357,
+    "name": "Amen",
+    "age": "20",
+    "type": "Teacher",
+    "specialization": "math"
+  }
+]

data/rentals.json

@@ -0,0 +1,7 @@
+[
+  {
+    "date": "02-02-20",
+    "people_index": 0,
+    "book_index": 0
+  }
+]

modules/book_mod.rb

@@ -18,6 +18,7 @@ def create_book
     book = Book.new(title, author)
     @books.push(book)
     puts 'Book created successfully!'
+    SaveData.new.save_books(@books)
   end
 
   def list_books_using_id

modules/people_mod.rb

@@ -34,6 +34,7 @@ def create_student
     student = Student.new(age, name, parent_permission)
     @people.push(student)
     puts 'Student added successfully!'
+    SaveData.new.save_people(@people)
   end
 
   def create_teacher
@@ -46,6 +47,7 @@ def create_teacher
     teacher = Teacher.new(age, name, specialization)
     @people.push(teacher)
     puts 'Teacher added successfully!'
+    SaveData.new.save_people(@people)
   end
 
   def list_people_using_id

modules/read_data.rb

@@ -0,0 +1,50 @@
+require 'json'
+
+class ReadData
+  def read_books
+    books = []
+    return books unless File.exist?('./data/books.json')
+
+    file = File.open('./data/books.json')
+    data = JSON.parse(file.read)
+    data.each do |book|
+      books << Book.new(book['title'], book['author'])
+    end
+    file.close
+    books
+  end
+
+  def read_people
+    people = []
+    return people unless File.exist?('./data/people.json')
+
+    file = File.open('./data/people.json')
+    data = JSON.parse(file.read)
+    file.close
+    data.each do |person|
+      if person['type'] == 'Student'
+        student = Student.new(person['age'], person['name'], person['parent_permission'])
+        student.id = person['id']
+        people << student
+      else
+        teacher = Teacher.new(person['age'], person['name'], person['parent_permission'])
+        teacher.id = person['id']
+        people << teacher
+      end
+    end
+    people
+  end
+
+  def read_rentals(books, people)
+    rentals = []
+    return rentals unless File.exist?('./data/rentals.json')
+
+    file = File.open('./data/rentals.json')
+    data = JSON.parse(file.read)
+    file.close
+    data.each do |rental|
+      rentals << Rental.new(rental['date'], books[rental['book_index']], people[rental['people_index']])
+    end
+    rentals
+  end
+end

modules/rental_mod.rb

@@ -12,6 +12,7 @@ def create_rental
     person = @people[select_person]
     rental = Rental.new(date, book, person)
     @rentals.push(rental)
+    SaveData.new.save_rentals(@rentals, @books, @people)
     puts 'Rental created successfully!'
   end
 

modules/save_data.rb

@@ -0,0 +1,63 @@
+require 'json'
+require 'fileutils'
+
+class SaveData
+  def exist_file(filename)
+    FileUtils.mkdir_p('./data')
+    FileUtils.touch('./data/books.json') if !File.exist?('./data/books.json') && filename == 'books'
+    FileUtils.touch('./data/people.json') if !File.exist?('./data/people.json') && filename == 'people'
+    FileUtils.touch('./data/rentals.json') if !File.exist?('./data/rentals.json') && filename == 'rentals'
+  end
+
+  def save_books(books)
+    book_arr = []
+    books.each do |book|
+      book_arr << { title: book.title, author: book.author }
+    end
+    return if book_arr.empty?
+
+    exist_file('books')
+    File.write('./data/books.json', JSON.pretty_generate(book_arr))
+  end
+
+  def save_people(people)
+    people_arr = []
+    people.each do |person|
+      person_obj = {
+        id: person.id,
+        name: person.name,
+        age: person.age,
+        type: person.class.name
+      }
+      if person.instance_of?(::Teacher)
+        person_obj[:specialization] = person.specialization
+      else
+        person_obj[:parent_permission] = person.parent_permission
+      end
+      people_arr << person_obj
+    end
+
+    return if people_arr.empty?
+
+    exist_file('people')
+    File.write('./data/people.json', JSON.pretty_generate(people_arr))
+  end
+
+  def save_rentals(rentals, books, people)
+    rentals_arr = []
+    rentals.each do |rental|
+      rental_obj = {
+        date: rental.date,
+        people_index: people.index(rental.person),
+        book_index: books.index(rental.book)
+      }
+      rentals_arr << rental_obj
+    end
+
+    return if rentals_arr.empty?
+
+    exist_file('rentals')
+
+    File.write('./data/rentals.json', JSON.pretty_generate(rentals_arr))
+  end
+end

modules/select.rb

@@ -1,4 +1,5 @@
 require_relative '../app'
+require_relative 'read_data'
 
 class Select
   def initialize

modules/student.rb

@@ -1,12 +1,13 @@
 require_relative 'person'
 
 class Student < Person
-  attr_reader :classroom
+  attr_reader :classroom, :parent_permission
+  attr_writer :id
 
-  def initialize(age, name, _parent_permission, classroom: 'Unknown')
+  def initialize(age, name, parent_permission, classroom: 'Unknown')
     super(age, name)
-    @id = Random.rand(1...100)
     @classroom = classroom
+    @parent_permission = parent_permission
   end
 
   def play_hooky

modules/teacher.rb

@@ -1,9 +1,11 @@
 require_relative 'person'
 
 class Teacher < Person
+  attr_accessor :specialization
+  attr_writer :id
+
   def initialize(age, name, specialization)
     super(age, name)
-    @id = Random.rand(1...1000)
     @specialization = specialization
   end