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# Terminal
docker run --name postgres -p 5432:5432 -e POSTGRES_PASSWORD=postgres -d postgres
docker stop postgres
docker start postgres
brew install ctop && ctop

rails g model author name
rails g model publisher name
rails g model genre name
rails g scaffold books title author:belongs_to publisher:belongs_to genre:belongs_to
rails g migration add_index_to_tables

bundle add faker
bundle add pg_search
bundle add kaminari

# config/database.yml
development:
  <<: *default
  database: template_development
  url: postgresql://postgres:[email protected]:5432/template_development

# db/seeds.rb
100.times do
  Author.create(name: Faker::Book.author)
end

100.times do
  Publisher.create(name: Faker::Book.author)
end

100.times do
  Genre.create(name: Faker::Book.genre)
end

100.times do
  [].tap do |array|
    10_000.times do
      time = Time.current
      array << {
        title: Faker::Book.title,
        author_id: 1 + rand(100),
        publisher_id: 1 + rand(100),
        genre_id: 1 + rand(100),
        updated_at: time,
        created_at: time
      }
    end
    Book.insert_all(array)
  end
end

# 1_000_000.times do
#   Book.create(
#     title: Faker::Book.title,
#     author_id: 1 + rand(100),
#     publisher_id: 1 + rand(100),
#     genre_id: 1 + rand(100)
#   )
# end

# books_controller.rb
def index
  @books = Book.search(params[:q])
    .includes(:author, :publisher, :genre)
    .page(params[:page])
    .without_count
    .per(8)
end

# models/book.rb
class Book < ApplicationRecord
  belongs_to :author
  belongs_to :publisher
  belongs_to :genre

  include PgSearch::Model
  pg_search_scope :pg_search,
    against: :title,
    using: {
      tsearch: { dictionary: 'english' }
    },
    associated_against: {
      author: :name,
      publisher: :name,
      genre: :name
    }

  def self.search(query)
    return all unless query.present?

    # where(title: query)

    # where("title ILIKE ?", "%#{query}%")

    # where("to_tsvector('english', title) @@ plainto_tsquery('english', :q)", q: query)

    # where("to_tsvector('english', title) @@ plainto_tsquery('english', :q)", q: query)
    # .joins(:author).or(Book.where("authors.name ILIKE ?", "%#{query}%"))
    # .joins(:publisher).or(Book.where("publishers.name ILIKE ?", "%#{query}%"))
    # .joins(:genre).or(Book.where("genres.name ILIKE ?", "%#{query}%"))

    pg_search(query)
  end
end


# views/books/index.html.erb
<%= form_with url: books_path, method: :get do |form| %>
  <div class='input-group'>
    <%= form.text_field :q, value: params[:q], placeholder: 'Search', class: 'form-control' %>
    <%= form.submit 'Search', class: 'btn btn-outline-secondary' %>
  </div>
<% end %>

<table class='table'>
  <thead>
    <th>Title</th>
    <th>Author</th>
    <th>Publisher</th>
    <th>Genre</th>

    <th colspan=3>Actions</th>
  </thead>
  <tbody>
    <% @books.each do |book| %>
      <tr>
        <td><%= highlight(book.title, query_array) %></td>
        <td><%= highlight(book.author.name, query_array) %></td>
        <td><%= highlight(book.publisher.name, query_array) %></td>
        <td><%= highlight(book.genre.name, query_array) %></td>

        <td><%= link_to "Show", book_path(book) %></td>
        <td><%= link_to "Edit", edit_book_path(book) %></td>
        <td><%= link_to "Delete", book_path(book), "data-turbo-method": :delete %></td>
      </tr>
    <% end %>
  </tbody>
</table>

<%# paginate @books %>
<%= link_to_prev_page @books, 'Previous Page', class: 'btn btn-outline-primary' %>
<%= link_to_next_page @books, 'Next Page', class: 'btn btn-outline-primary' %>

# app/helpers/application_helper.rb
module ApplicationHelper
  def query_array
    params[:q].to_s.split(' ')
  end
end

# db/migrate/XXXXXXXX_add_index_to_tables.rb
class AddIndexToTables < ActiveRecord::Migration[7.0]
  def change
    add_index :books, "to_tsvector('english', title)", using: :gin
    add_index :authors, "to_tsvector('english', name)", using: :gin
    add_index :publishers, "to_tsvector('english', name)", using: :gin
    add_index :genres, "to_tsvector('english', name)", using: :gin
  end
end