#!/usr/bin/env ruby

require 'net/http'
require 'uri'
require 'json'

def get_ticket(un, tgt, sv)
  uri = URI.parse("http://localhost:4567/ticket")
  header = {'Content-Type': 'text/json'}

  login = {
    "username": un,
    "ticket": tgt,
    "service": sv
  }

  http = Net::HTTP.new(uri.host, uri.port)
  request = Net::HTTP::Post.new(uri.request_uri, header)
  request.body = login.to_json

  response = http.request(request)
  response.body
end

print "Username: "; un = gets.strip
print "Mailserver: "; ms = gets.strip

unless File.exist?(".keytab")
  puts "No keytab, please kinit"
  exit 1
end

Keys = File.readlines(".keytab").map{ |l| l.strip.split(?:) }.to_h

if Keys.keys.include?(ms)
  ticket = Keys[ms]
elsif Keys.keys.include?("_TGS")
  ticket = get_ticket(un, Keys["_TGS"], ms)
  File.open(".keytab", ?a) do |f|
    f.puts "#{ms}:#{ticket}"
  end
else
  puts "No Ticket Granting Ticket, please kinit"
  exit 1
end

uri = URI.parse("http://localhost:4568/login")
header = {'Content-Type': 'text/json'}

login = {
  "username": un,
  "ticket": ticket
}

http = Net::HTTP.new(uri.host, uri.port)
request = Net::HTTP::Post.new(uri.request_uri, header)
request.body = login.to_json

response = http.request(request)
puts response.body