class Faker::Internet

def base64(length: 16, padding: false, urlsafe: true)
  char_range = [
    Array('0'..'9'),
    Array('A'..'Z'),
    Array('a'..'z'),
    urlsafe ? %w[- _] : %w[+ /]
  ].flatten
  s = Array.new(length) { sample(char_range) }.join
  s += '=' if padding
  s
end

def bot_user_agent(vendor: nil)
  agent_hash = translate('faker.internet.bot_user_agent')
  agents = vendor.respond_to?(:to_sym) && agent_hash[vendor.to_sym] || agent_hash[sample(agent_hash.keys)]
  sample(agents)
end

def construct_email(local_part, domain_name)
  [local_part, domain_name].join('@')
end

def device_token
  shuffle(rand(16**64).to_s(16).rjust(64, '0').chars.to_a).join
end

def domain_name(subdomain: false, domain: nil)
  with_locale(:en) do
    if domain
      domain
        .split('.')
        .map { |domain_part| Char.prepare(domain_part) }
        .tap do |domain_elements|
          if domain_elements.length < 2
            domain_elements << domain_suffix(safe: true)
          end
          if subdomain && domain_elements.length < 3
            domain_elements.unshift(Char.prepare(domain_word))
          end
        end.join('.')
    else
      [domain_word, domain_suffix(safe: true)].tap do |domain_elements|
        if subdomain
          domain_elements.unshift(Char.prepare(domain_word))
        end
      end.join('.')
    end
  end
end

def domain_suffix(safe: nil)
  if safe
    fetch('internet.safe_domain_suffix')
  else
    fetch('internet.domain_suffix')
  end
end

def domain_word
  with_locale(:en) { Char.prepare(Company.name.split.first) }
end

def email(name: nil, separators: nil, domain: nil)
  local_part = if separators
                 username(specifier: name, separators: separators)
               else
                 username(specifier: name)
               end
  sanitized_local_part = sanitize_email_local_part(local_part)
  generate_domain = if domain.nil?
                      domain_name
                    else
                      domain_name(domain: domain)
                    end
  construct_email(sanitized_local_part, generate_domain)
end

def fix_umlauts(string: '')
  Char.fix_umlauts(string)
end

def free_email(name: nil)
  construct_email(
    sanitize_email_local_part(username(specifier: name)),
    fetch('internet.free_email')
  )
end

def ip_v4_address
  [rand_in_range(0, 255), rand_in_range(0, 255),
   rand_in_range(0, 255), rand_in_range(0, 255)].join('.')
end

def ip_v4_cidr
  "#{ip_v4_address}/#{rand(1..31)}"
end

def ip_v6_address
  (1..8).map { rand(65_536).to_s(16) }.join(':')
end

def ip_v6_cidr
  "#{ip_v6_address}/#{rand(1..127)}"
end

def mac_address(prefix: '')
  prefix_digits = prefix.split(':').map { |d| d.to_i(16) }
  address_digits = Array.new((6 - prefix_digits.size)) { rand(256) }
  (prefix_digits + address_digits).map { |d| format('%02x', d) }.join(':')
end

def password(min_length: 8, max_length: 16, mix_case: true, special_characters: false)
  raise ArgumentError, 'min_length and max_length must be greater than or equal to one' if min_length < 1 || max_length < 1
  raise ArgumentError, 'min_length must be smaller than or equal to max_length' unless min_length <= max_length
  character_types = []
  required_min_length = 0
  if mix_case
    character_types << :mix_case
    required_min_length += 2
  end
  if special_characters
    character_types << :special_characters
    required_min_length += 1
  end
  raise ArgumentError, "min_length should be at least #{required_min_length} to enable #{character_types.join(', ')} configuration" if min_length < required_min_length
  target_length = rand(min_length..max_length)
  password = []
  character_bag = []
  # use lower_chars by default and add upper_chars if mix_case
  lower_chars = self::LLetters
  password << sample(lower_chars)
  character_bag += lower_chars
  digits = ('0'..'9').to_a
  password << sample(digits)
  character_bag += digits
  if mix_case
    upper_chars = self::ULetters
    password << sample(upper_chars)
    character_bag += upper_chars
  end
  if special_characters
    special_chars = %w[! @ # $ % ^ & *]
    password << sample(special_chars)
    character_bag += special_chars
  end
  password << sample(character_bag) while password.length < target_length
  shuffle(password).join
end

def private_ip_v4_address
  sample(PRIVATE_IPV4_ADDRESS_RANGES).map { |range| rand(range) }.join('.')
end

def private_net_checker
  ->(addr) { private_nets_regex.any? { |net| net =~ addr } }
end

def private_nets_regex
  [
    /^10\./,                                       # 10.0.0.0    - 10.255.255.255
    /^100\.(6[4-9]|[7-9]\d|1[0-1]\d|12[0-7])\./,   # 100.64.0.0  - 100.127.255.255
    /^127\./,                                      # 127.0.0.0   - 127.255.255.255
    /^169\.254\./,                                 # 169.254.0.0 - 169.254.255.255
    /^172\.(1[6-9]|2\d|3[0-1])\./,                 # 172.16.0.0  - 172.31.255.255
    /^192\.0\.0\./,                                # 192.0.0.0   - 192.0.0.255
    /^192\.168\./,                                 # 192.168.0.0 - 192.168.255.255
    /^198\.(1[8-9])\./                             # 198.18.0.0  - 198.19.255.255
  ]
end

def public_ip_v4_address
  addr = nil
  loop do
    addr = ip_v4_address
    break unless reserved_net_checker[addr]
  end
  addr
end

def reserved_net_checker
  ->(addr) { (private_nets_regex + reserved_nets_regex).any? { |net| net =~ addr } }
end

def reserved_nets_regex
  [
    /^0\./,                 # 0.0.0.0      - 0.255.255.255
    /^192\.0\.2\./,         # 192.0.2.0    - 192.0.2.255
    /^192\.88\.99\./,       # 192.88.99.0  - 192.88.99.255
    /^198\.51\.100\./,      # 198.51.100.0 - 198.51.100.255
    /^203\.0\.113\./,       # 203.0.113.0  - 203.0.113.255
    /^(22[4-9]|23\d)\./,    # 224.0.0.0    - 239.255.255.255
    /^(24\d|25[0-5])\./     # 240.0.0.0    - 255.255.255.254  and  255.255.255.255
  ]
end

def safe_email(name: nil)
  construct_email(
    sanitize_email_local_part(username(specifier: name)),
    "example.#{sample(%w[org com net])}"
  )
end

def sanitize_email_local_part(local_part)
  char_range = [
    Array('0'..'9'),
    Array('A'..'Z'),
    Array('a'..'z'),
    "!#$%&'*+-/=?^_`{|}~.".chars
  ].flatten
  local_part.chars.map do |char|
    char_range.include?(char) ? char : '#'
  end.join
end

def slug(words: nil, glue: nil)
  glue ||= sample(%w[- _])
  return words.delete(',.').gsub(' ', glue).downcase unless words.nil?
  sample(translate('faker.internet.slug'), 2).join(glue)
end

def url(host: domain_name, path: "/#{username}", scheme: 'http')
  "#{scheme}://#{host}#{path}"
end

def user(*args)
  user_hash = {}
  args = %w[username email] if args.empty?
  args.each { |arg| user_hash[:"#{arg}"] = send(arg) }
  user_hash
end

def user_agent(vendor: nil)
  agent_hash = translate('faker.internet.user_agent')
  agents = vendor.respond_to?(:to_sym) && agent_hash[vendor.to_sym] || agent_hash[sample(agent_hash.keys)]
  sample(agents)
end

def username(specifier: nil, separators: %w[. _])
  with_locale(:en) do
    return shuffle(specifier.scan(/[[:word:]]+/)).join(sample(separators)).downcase if specifier.respond_to?(:scan)
    case specifier
    when Integer
      # If specifier is Integer and has large value, Argument error exception is raised to overcome memory full error
      raise ArgumentError, 'Given argument is too large' if specifier > 10**6
      tries = 0 # Don't try forever in case we get something like 1_000_000.
      result = nil
      loop do
        result = username(specifier: nil, separators: separators)
        tries += 1
        break unless result.length < specifier && tries < 7
      end
      return result * (specifier / result.length + 1) if specifier.positive?
    when Range
      tries = 0
      result = nil
      loop do
        result = username(specifier: specifier.min, separators: separators)
        tries += 1
        break unless !specifier.include?(result.length) && tries < 7
      end
      return result[0...specifier.max]
    end
    sample([
             Char.prepare(Name.first_name),
             [Name.first_name, Name.last_name].map do |name|
               Char.prepare(name)
             end.join(sample(separators))
           ])
  end
end

def uuid
  # borrowed from: https://github.com/ruby/ruby/blob/d48783bb0236db505fe1205d1d9822309de53a36/lib/securerandom.rb#L250
  ary = Faker::Config.random.bytes(16).unpack('NnnnnN')
  ary[2] = (ary[2] & 0x0fff) | 0x4000
  ary[3] = (ary[3] & 0x3fff) | 0x8000
  '%08x-%04x-%04x-%04x-%04x%08x' % ary # rubocop:disable Style/FormatString
end