describe CustomFields::Types::ManyToMany do

  before(:each) do
    @blog     = create_blog
    @post_1   = @blog.posts.create title: 'Hello world', body: 'Lorem ipsum...', published: true
    @post_2   = @blog.posts.create title: 'High and Dry', body: 'Lorem ipsum...', published: false
    @post_3   = @blog.posts.create title: 'Nude', body: 'Lorem ipsum...', published: true
    @author_1 = @blog.people.create name: 'John Doe'
    @author_2 = @blog.people.create name: 'Jane Doe'
  end

  it 'assigns posts to an author' do
    author = assign_posts_to_author @author_1, [@post_1, @post_3]

    expect(author.posts.map(&:title)).to eq ['Nude', 'Hello world']
  end

  it 'assigns posts to authors' do
    author_1 = assign_posts_to_author @author_1, [@post_1, @post_3]
    author_2 = assign_posts_to_author @author_2, [@post_2, @post_3]

    expect(author_1.posts.map(&:title)).to eq ['Nude', 'Hello world']
    expect(author_2.posts.map(&:title)).to eq ['Nude', 'High and Dry']
  end

  it 'returns the authors of a post' do
    assign_posts_to_author @author_1, [@post_1, @post_3]
    assign_posts_to_author @author_2, [@post_2, @post_3]

    @post_3 = Post.find @post_3._id

    expect(@post_3.authors.map(&:name)).to eq ['John Doe', 'Jane Doe']
  end

  it 'returns the posts based on the order in the post_ids field' do
    assign_posts_to_author @author_1, [@post_1, @post_3, @post_2]

    author = Person.find @author_1._id

    expect(author.posts.filtered.map(&:title)).to eq ['Hello world', 'Nude', 'High and Dry']
    expect(author.posts.map(&:title)).to eq ['Nude', 'High and Dry', 'Hello world']
  end

  it 'filters the posts' do
    assign_posts_to_author @author_1, [@post_1, @post_3, @post_2]

    author = Person.find @author_1._id

    expect(author.posts.filtered({ published: true }).map(&:title)).to eq ['Hello world', 'Nude']
  end

  it 'orders the posts but not load all the attributes' do
    assign_posts_to_author @author_1, [@post_1, @post_3, @post_2]

    author = Person.find @author_1._id

    expect(author.posts.pluck_with_natural_order(:title)).to eq ['Hello world', 'Nude', 'High and Dry']
    expect(author.posts.pluck_with_natural_order(:title, :published)).to eq [['Hello world', true], ['Nude', true], ['High and Dry', false]]
  end

  it 'filters and orders the posts' do
    author = assign_posts_to_author @author_1, [@post_1, @post_3, @post_2]

    expect(author.posts.filtered({ published: true }, %w[title desc]).map(&:title)).to eq ['Nude', 'Hello world']
  end

  it 'works even if the related model is deleted' do
    author = assign_posts_to_author @author_1, [@post_1, @post_3, @post_2]

    # Mimic the deletion of a model and its data
    [@post_1, @post_3, @post_2].collect(&:delete)
    Object.send :remove_const, "Post#{@blog._id}"

    expect { author.reload.posts.map(&:title) }.to_not raise_error
  end

  protected

  def create_blog
    Blog.new(name: 'My personal blog').tap do |blog|
      blog.people_custom_fields.build label: 'Posts',     type: 'many_to_many', class_name: "Post#{blog._id}", inverse_of: :authors, order_by: ['title', 'desc']
      blog.posts_custom_fields.build  label: 'Authors',   type: 'many_to_many', class_name: "Person#{blog._id}", inverse_of: :posts
      blog.posts_custom_fields.build  label: 'Published', type: 'boolean'

      blog.save & blog.reload
    end
  end

  def assign_posts_to_author(author, posts)
    author.posts = posts

    author.save

    Person.find author._id
  end

end
