class LivestatusClient

# File lib/livestatus-client.rb, line 123
def columns
  return [key] unless opts[:columns]
  [key] + opts[:columns].split(',')
end

# File lib/livestatus-client.rb, line 29
def command
  args = [opts[:command]] + opts[:arguments].split(',')
  cmd_string = "COMMAND [#{Time.now.to_i}] #{args.join(';')}\n" \
    "ResponseHeader: fixed16\n" \
    "OutputFormat: json\n"

  socket.write cmd_string + "\n"
  response = read
  socket.close
  puts response
end

# File lib/livestatus-client.rb, line 20
def display_columns
  printf "%-30s %-9s %s\n", 'column', '(type)', 'description'
  120.times { print '-' }
  puts
  query('columns').select { |col| col[2] == opts[:query] }.each do |col|
    printf "%-30s %-9s %s\n", col[1], "(#{col[3]})", col[0]
  end
end

# File lib/livestatus-client.rb, line 41
def key
  key_map = {
    'downtimes' => 'id',
    'services' => 'description',
    'servicesbygroup' => 'description',
    'servicesbyhostgroup' => 'description',
    'comments' => 'service_description'
  }

  key_map[opts[:query]] || 'name'
end

# File lib/livestatus-client.rb, line 128
def opts
  @opts ||= begin
    opts = Trollop.options do
      version "livestatus-client #{LivestatusClient::VERSION} (c) 2017 Evertrue"
      opt :host, 'Livestatus host', short: 'h', type: String
      opt :port, 'Livestatus port', short: 'p', type: String
      opt :query, 'The query string', short: 'q', type: String
      opt :columns, 'Which columns to display (comma separated)', short: 'l', type: String
      opt :list, 'List available columns'
      opt :command, 'Command to send', short: 'c', type: String
      opt :arguments, 'Command argumenets (comma separated)', short: 'a', type: String
    end

    fail 'Either a query or a command must be specified' unless opts[:query] || opts[:command]

    opts
  end
end

# File lib/livestatus-client.rb, line 66
def parse(data)
  # Outputs a somewhat more useful data structure that looks like this:
  #
  # {
  #   "item1": {
  #     "column1": [
  #       "value1",
  #       "value2"
  #     ],
  #     "column2": [
  #       "value1",
  #       "value2"
  #     ]
  #   },
  #   "item2": {
  #     "column1": [
  #     ],
  #     "column2": [
  #       "value1"
  #     ]
  #   }
  # }

  data.each_with_object({}) do |item, memo|
    item_name = item.shift
    # columns[1..-1] because we assume the first value is a name or id tag
    memo[item_name] = columns[1..-1].each_with_object({}) do |col, cols_memo|
      cols_memo[col] = item.shift
    end
  end
end

# File lib/livestatus-client.rb, line 53
def query(keyword)
  query_string = "GET #{keyword}\n" \
    "ResponseHeader: fixed16\n" \
    "OutputFormat: json\n"
  query_string += "Columns: #{columns.join ' '}\n" unless opts[:list]

  socket.write query_string + "\n"
  response = read
  socket.close
  return response unless opts[:columns]
  parse response
end

# File lib/livestatus-client.rb, line 98
def read
  header = socket.read 16

  response = {
    code: header[0..2].to_i,
    length: header[4..14].chomp.to_i
  }

  fail "Received error response #{response[:code]}" unless response[:code] == 200

  JSON.parse socket.read response[:length]
end

# File lib/livestatus-client.rb, line 8
def run
  if opts[:query]
    if opts[:list]
      display_columns
    else
      puts JSON.pretty_generate query opts[:query]
    end
  elsif opts[:command]
    command
  end
end

# File lib/livestatus-client.rb, line 111
def socket
  return @socket unless !@socket || @socket.closed?
  @socket = TCPSocket.open opts[:host], opts[:port]
end