class JsonConverter

# File lib/json_converter.rb, line 6
def generate_csv(json, headers=true, nil_substitute='')
  csv = convert_to_csv json, nil_substitute
  headers_written = false

  generated_csv = CSV.generate do |output|
    csv.each do |row|
      if headers && !headers_written
        output << row.keys && headers_written = true
      end

      output << row.values
    end
  end

  generated_csv
end

# File lib/json_converter.rb, line 24
def write_to_csv(json, output_filename='out.csv', headers=true, nil_substitute='')
  csv = convert_to_csv json, nil_substitute
  headers_written = false

  CSV.open(output_filename.to_s, 'w') do |output_file|
    csv.each do |row|
      if headers && !headers_written
        output_file << row.keys && headers_written = true
      end

      output_file << row.values
    end
  end
end

# File lib/json_converter.rb, line 97
def array_from(json_hash)
  queue, next_item = [], json_hash
  while !next_item.nil?

    return next_item if next_item.is_a? Array

    if next_item.is_a? Hash
      next_item.each do |k, v|
        queue.push next_item[k]
      end
    end

    next_item = queue.shift
  end

  return [json_hash]
end

# File lib/json_converter.rb, line 42
def convert_to_csv(json, nil_substitute)
  json = JSON.parse json if json.is_a? String

  in_array = array_from json
  out_array = []

  # Replace all nil values with the value of nil_substitute; The presence
  # of nil values in the data will usually result in uneven rows
  in_array.map! { |x| nils_to_strings x, nil_substitute }

  in_array.each do |row|
    out_array[out_array.length] = flatten row
  end

  out_array
end

# File lib/json_converter.rb, line 74
def flatten(target, path='')
  scalars = [String, Integer, Float, FalseClass, TrueClass]
  columns = {}

  if [Hash, Array].include? target.class
    target.each do |k, v|
      new_columns = flatten(v, "#{path}#{k}/") if target.class == Hash
      new_columns = flatten(k, "#{path}#{k}/") if target.class == Array
      columns = columns.merge new_columns
    end

    return columns
  elsif scalars.include? target.class
      # Remove trailing slash from path
      end_path = path[0, path.length - 1]
      columns[end_path] = target
      return columns
  else
    return {}
  end
end

# File lib/json_converter.rb, line 60
def nils_to_strings(hash, replacement)
  hash.each_with_object({}) do |(k,v), object|
    case v
    when Hash
      object[k] = nils_to_strings v, replacement
    when nil
      object[k] = replacement.to_s
    else
      object[k] = v
    end
  end
end