A wrapper script for tradedangerous.

trade.rb

#!/usr/bin/env ruby

# A wrapper around Trade Dangerous that persists settings in a local JSON file.

require 'json'

class Trader
  attr_reader :data

  def initialize(data:)
    @data = data
    fail "Script does not exist at #{location}." unless File.exists?(location)
  end

  def calculate!
    arguments = keys_and_args.each_with_object([]) do |(key, arg), array|
      value = data[key.to_s]
      next if value.nil?

      value = value.map { |v| %Q("#{v}") }.join(',') if key == :avoid
      array << "--#{arg} #{value}"
    end

    puts "Calculating trade run...\n\n"
    value = execute('run -vvv', arguments.join(' '))
  end

  def update!
    execute 'import', '--plug=maddavo'
  end

  private

  def execute(command, arguments)
    system("python #{location} #{command} #{arguments}")
  end

  def keys_and_args
    {
      from: 'from',
      credits: 'credits',
      insurance: 'insurance',
      capacity: 'capacity',
      empty_ly: 'empty-ly',
      ly_per: 'ly-per',
      ls_max: 'ls-max',
      avoid: 'avoid',
      hops: 'hops',
      jumps: 'jumps',
      start_jumps: 'start-jumps'
    }
  end

  def location
    File.expand_path(File.join('~', 'Code', 'bitbucket', 'kfsone',
                               'tradedangerous', 'trade.py'))
  end
end

class Persister
  attr_reader :data
  def initialize
    @data = File.exists?(location) ? JSON.parse(IO.read(location)) : {}
  end

  def for_key(key)
    data[key.to_s]
  end

  def set_value(value, for_key:)
    return if value.nil? || value == ""
    if for_key == :avoid && value.is_a?(String)
      value = value.split(",").map(&:strip)
    end
    data[for_key.to_s] = value
  end

  def clear_value_for_key(key)
    data[key.to_s] = nil
  end

  def persist!
    FileUtils.mkdir_p(File.dirname(location))
    File.open(location, 'w') { |f| f.write(JSON.pretty_generate(data)) }
  end

  private

  def location
    File.expand_path(File.join('~', '.tradedangerous', 'trade-settings.json'))
  end
end

class Asker
  attr_reader :settings

  def initialize(settings: Persister.new)
    @settings = settings
  end

  def ask_and_persist!
    ask!
    settings.persist!
  end

  def ask!
    questions.each do |key, question|
      to_ask = question
      to_ask += " (Previous: #{settings.for_key(key)})" if settings.for_key(key)
      puts to_ask
      value = gets.chomp
      settings.set_value(value, for_key: key)
    end
  end

  private

  def questions
    {
      from: 'Where are you now?',
      credits: 'How much money do you have?',
      insurance: 'Insurance amount?',
      capacity: 'Cargo capacity?',
      empty_ly: 'Max distance per jump?',
      ly_per: 'Max distance per jump, laden?',
      ls_max: 'Max distance per station from star?',
      avoid: 'Anything to avoid?',
      hops: 'How many hops?',
      jumps: 'How many jumps per hop?',
      start_jumps: 'How many jumps out to start?'
    }
  end
end

is_quick = ARGV[0] && ARGV[0] == "quick"

settings = Persister.new
if !is_quick
  asker = Asker.new(settings: settings)
  asker.ask_and_persist!
end
trader = Trader.new(data: settings.data)
trader.calculate!