module ReversibilityChecker

# File lib/reversibility_checker.rb, line 21
def self.current_version(config)
  return ENV["CURRENT_VERSION"].to_i unless ENV["CURRENT_VERSION"].nil?

  ActiveRecord::Base.establish_connection(config)
  version = ActiveRecord::Migrator.current_version
  ActiveRecord::Base.remove_connection

  return version
end

# File lib/reversibility_checker.rb, line 8
def self.dump(config)
  case ActiveRecord::Base.schema_format
  when :ruby
    buffer = StringIO.new
    ActiveRecord::SchemaDumper.dump(ActiveRecord::Base.connection, buffer)
    buffer.string
  when :sql
    file = Tempfile.new
    ActiveRecord::Tasks::DatabaseTasks.structure_dump(config, file.path)
    file.read
  end
end

# File lib/reversibility_checker.rb, line 31
def self.target_versions(config, current_version)
  ActiveRecord::Base.establish_connection(config)
  migration_context = ActiveRecord::Base.connection.migration_context
  ActiveRecord::Base.remove_connection

  versions = ActiveRecord::Tasks::DatabaseTasks.migrations_paths.flat_map do |migrations_path|
    Dir["#{migrations_path}/*.rb"].map do |filepath|
      migration_context.parse_migration_filename(filepath).first.to_i
    end
  end
  versions.select { |version| version > current_version }.sort
end