require 'mysql2'
require 'singleton'

class DatabaseConnection
  include Singleton

  def initialize
    @client = Mysql2::Client.new(
      host: 'localhost',
      username: 'project_user',
      password: 'project_password',
      database: 'project_db'
    )
  end

  def client
    @client
  end

  def query(sql)
    @client.query(sql)
  end
end