class Eco::API::Common::People::DefaultParsers::CSVParser < Eco::API::Common::Loaders::Parser
  attribute :csv

  def parser(data, deps)
    Eco::CSV.parse(data, headers: true, skip_blanks: true).each_with_object([]) do |row, arr_hash|
      row_hash = row.headers.uniq.each_with_object({}) do |attr, hash|
        next if attr.to_s.strip.empty?
        hash[attr.strip] = parse_string(row[attr])
      end
      arr_hash.push(row_hash)
    end
  end

  def serializer(array_hash, deps)
    arr_rows = []
    unless array_hash.empty?
      header = array_hash.first.keys
      arr_rows = array_hash.map do |csv_row|
        CSV::Row.new(header, csv_row.values_at(*header))
      end
    end
    CSV::Table.new(arr_rows).to_csv
  end

  private

  def parse_string(value)
    return nil if value.to_s.empty?
    return nil if null?(value)
    value
  end

  def null?(value)
    return true if !value
    str = value.strip.upcase
    ["NULL"].any? {|token| str == token}
  end

end