module Geocoder::Request

def geocoder_reject_non_ipv4_addresses(ip_addresses)
  ips = []
  for ip in ip_addresses
    begin
      valid_ip = IPAddr.new(ip)
    rescue
      valid_ip = false
    end
    ips << valid_ip.to_s if valid_ip
  end
  return ips.any? ? ips : ip_addresses
end

def geocoder_reject_trusted_ip_addresses(ip_addresses)
  ip_addresses.reject { |ip| trusted_proxy?(ip) }
end

def geocoder_remove_port_from_addresses(ip_addresses)
  ip_addresses.map do |ip|
    # IPv4
    if ip.count('.') > 0
      ip.split(':').first
    # IPv6 bracket notation
    elsif match = ip.match(/\[(\S+)\]/)
      match.captures.first
    # IPv6 bare notation
    else
      ip
    end
  end
end

def geocoder_split_ip_addresses(ip_addresses)
  ip_addresses ? ip_addresses.strip.split(/[,\s]+/) : []
end

def geocoder_spoofable_ip
  # We could use a more sophisticated IP-guessing algorithm here,
  # in which we'd try to resolve the use of different headers by
  # different proxies.  The idea is that by comparing IPs repeated
  # in different headers, you can sometimes decide which header
  # was used by a proxy further along in the chain, and thus
  # prefer the headers used earlier.  However, the gains might not
  # be worth the performance tradeoff, since this method is likely
  # to be called on every request in a lot of applications.
  GEOCODER_CANDIDATE_HEADERS.each do |header|
    if @env.has_key? header
      addrs = geocoder_split_ip_addresses(@env[header])
      addrs = geocoder_remove_port_from_addresses(addrs)
      addrs = geocoder_reject_non_ipv4_addresses(addrs)
      addrs = geocoder_reject_trusted_ip_addresses(addrs)
      return addrs.first if addrs.any?
    end
  end
  @env['REMOTE_ADDR']
end

def location
  @location ||= Geocoder.search(geocoder_spoofable_ip, ip_address: true).first
end

def safe_location
  @safe_location ||= Geocoder.search(ip, ip_address: true).first
end