module Deepenv

# File lib/deepenv.rb, line 30
def parse_env_value(val_in) 
  val = val_in.strip
  if /^ +$/ =~ val_in then  # if one ore more whitespaces only, assume it's on purpose
    val_in
  elsif val === '' then     # blank goes to nil
    nil
  elsif val === 'null' then # return null as string so as not to be parsed by json later
    val 
  elsif /^\d+\.\d+$/ =~ val
    val.to_f
  elsif /^\d+$/ =~ val
    val.to_i
  elsif /^true$/i =~ val
    true
  elsif /^false$/i =~ val
    false
  else 
    begin
      JSON.parse(val)
    rescue
      val
    end
  end
end

# File lib/deepenv.rb, line 11
def to_config (original={}, opts={})
  @@prefix = opts.fetch(:prefix, "DEEPENV_")
  @@nesting_delimiter = opts.fetch(:nesting_delimiter, '__').downcase

  ENV.filter {|k| k.start_with? @@prefix}
  .map {|k, v| [k, parse_env_value(v)]}
  .each_with_object(
    original.deep_dup()
  ) do |kv,hash| 
    hash.deep_set(
        kv[0].dup
          .downcase!
          .sub(/^#{Regexp.escape(@@prefix.downcase)}/, '') 
          .split(@@nesting_delimiter).map(&:to_sym),
        kv[1]
      ) 
  end
end