module Stripe::Util

def self.check_api_key!(key)
  raise TypeError, "api_key must be a string" unless key.is_a?(String)
  key
end

def self.check_string_argument!(key)
  raise TypeError, "argument must be a string" unless key.is_a?(String)
  key
end

def self.colorize(val, color, isatty)
  return val unless isatty
  mode = 0 # default
  foreground = 30 + COLOR_CODES.fetch(color)
  background = 40 + COLOR_CODES.fetch(:default)
  "\033[#{mode};#{foreground};#{background}m#{val}\033[0m"
end

def self.convert_to_stripe_object(data, opts = {})
  opts = normalize_opts(opts)
  case data
  when Array
    data.map { |i| convert_to_stripe_object(i, opts) }
  when Hash
    # Try converting to a known object class.  If none available, fall back
    # to generic StripeObject
    object_classes.fetch(data[:object], StripeObject)
                  .construct_from(data, opts)
  else
    data
  end
end

def self.encode_parameters(params)
  Util.flatten_params(params)
      .map { |k, v| "#{url_encode(k)}=#{url_encode(v)}" }.join("&")
end

def self.flatten_params(params, parent_key = nil)
  result = []
  # do not sort the final output because arrays (and arrays of hashes
  # especially) can be order sensitive, but do sort incoming parameters
  params.each do |key, value|
    calculated_key = parent_key ? "#{parent_key}[#{key}]" : key.to_s
    if value.is_a?(Hash)
      result += flatten_params(value, calculated_key)
    elsif value.is_a?(Array)
      result += flatten_params_array(value, calculated_key)
    else
      result << [calculated_key, value]
    end
  end
  result
end

def self.flatten_params_array(value, calculated_key)
  result = []
  value.each_with_index do |elem, i|
    if elem.is_a?(Hash)
      result += flatten_params(elem, "#{calculated_key}[#{i}]")
    elsif elem.is_a?(Array)
      result += flatten_params_array(elem, calculated_key)
    else
      result << ["#{calculated_key}[#{i}]", elem]
    end
  end
  result
end

def self.level_name(level)
  case level
  when LEVEL_DEBUG then "debug"
  when LEVEL_ERROR then "error"
  when LEVEL_INFO  then "info"
  else level
  end
end

def self.log_debug(message, data = {})
  if !Stripe.logger.nil? ||
     !Stripe.log_level.nil? && Stripe.log_level <= Stripe::LEVEL_DEBUG
    log_internal(message, data, color: :blue, level: Stripe::LEVEL_DEBUG,
                                logger: Stripe.logger, out: $stdout)
  end
end

def self.log_error(message, data = {})
  if !Stripe.logger.nil? ||
     !Stripe.log_level.nil? && Stripe.log_level <= Stripe::LEVEL_ERROR
    log_internal(message, data, color: :cyan, level: Stripe::LEVEL_ERROR,
                                logger: Stripe.logger, out: $stderr)
  end
end

def self.log_info(message, data = {})
  if !Stripe.logger.nil? ||
     !Stripe.log_level.nil? && Stripe.log_level <= Stripe::LEVEL_INFO
    log_internal(message, data, color: :cyan, level: Stripe::LEVEL_INFO,
                                logger: Stripe.logger, out: $stdout)
  end
end

def self.log_internal(message, data = {}, color: nil, level: nil,
                      logger: nil, out: nil)
  data_str = data.reject { |_k, v| v.nil? }
                 .map do |(k, v)|
    format("%<key>s=%<value>s",
           key: colorize(k, color, logger.nil? && !out.nil? && out.isatty),
           value: wrap_logfmt_value(v))
  end.join(" ")
  if !logger.nil?
    # the library's log levels are mapped to the same values as the
    # standard library's logger
    logger.log(level,
               format("message=%<message>s %<data_str>s",
                      message: wrap_logfmt_value(message),
                      data_str: data_str))
  elsif out.isatty
    out.puts format("%<level>s %<message>s %<data_str>s",
                    level: colorize(level_name(level)[0, 4].upcase,
                                    color, out.isatty),
                    message: message,
                    data_str: data_str)
  else
    out.puts format("message=%<message>s level=%<level>s %<data_str>s",
                    message: wrap_logfmt_value(message),
                    level: level_name(level),
                    data_str: data_str)
  end
end

def self.normalize_headers(headers)
  headers.each_with_object({}) do |(k, v), new_headers|
    k = k.to_s.tr("_", "-") if k.is_a?(Symbol)
    k = k.split("-").reject(&:empty?).map(&:capitalize).join("-")
    new_headers[k] = v
  end
end

def self.normalize_id(id)
  if id.is_a?(Hash) # overloaded id
    params_hash = id.dup
    id = params_hash.delete(:id)
  else
    params_hash = {}
  end
  [id, params_hash]
end

def self.normalize_opts(opts)
  case opts
  when String
    { api_key: opts }
  when Hash
    check_api_key!(opts.fetch(:api_key)) if opts.key?(:api_key)
    opts.clone
  else
    raise TypeError, "normalize_opts expects a string or a hash"
  end
end

def self.object_classes
  @object_classes ||= Stripe::ObjectTypes.object_names_to_classes
end

def self.objects_to_ids(obj)
  case obj
  when APIResource
    obj.id
  when Hash
    res = {}
    obj.each { |k, v| res[k] = objects_to_ids(v) unless v.nil? }
    res
  when Array
    obj.map { |v| objects_to_ids(v) }
  else
    obj
  end
end

def self.request_id_dashboard_url(request_id, api_key)
  env = !api_key.nil? && api_key.start_with?("sk_live") ? "live" : "test"
  "https://dashboard.stripe.com/#{env}/logs/#{request_id}"
end

def self.secure_compare(str_a, str_b)
  return false unless str_a.bytesize == str_b.bytesize
  l = str_a.unpack "C#{str_a.bytesize}"
  res = 0
  str_b.each_byte { |byte| res |= byte ^ l.shift }
  res.zero?
end

def self.symbolize_names(object)
  case object
  when Hash
    new_hash = {}
    object.each do |key, value|
      key = (begin
               key.to_sym
             rescue StandardError
               key
             end) || key
      new_hash[key] = symbolize_names(value)
    end
    new_hash
  when Array
    object.map { |value| symbolize_names(value) }
  else
    object
  end
end

def self.url_encode(key)
  CGI.escape(key.to_s).
    # Don't use strict form encoding by changing the square bracket control
    # characters back to their literals. This is fine by the server, and
    # makes these parameter strings easier to read.
    gsub("%5B", "[").gsub("%5D", "]")
end

def self.wrap_logfmt_value(val)
  # If value is any kind of number, just allow it to be formatted directly
  # to a string (this will handle integers or floats).
  return val if val.is_a?(Numeric)
  # Hopefully val is a string, but protect in case it's not.
  val = val.to_s
  if %r{[^\w\-/]} =~ val
    # If the string contains any special characters, escape any double
    # quotes it has, remove newlines, and wrap the whole thing in quotes.
    format(%("%<value>s"), value: val.gsub('"', '\"').delete("\n"))
  else
    # Otherwise use the basic value if it looks like a standard set of
    # characters (and allow a few special characters like hyphens, and
    # slashes)
    val
  end
end