module Flucti
  module Parameters
    extend self
    extend Utilities

    def store_dir
      @store_dir ||= begin
        options = []
        options << Pathname(ENV['APPDATA']) / 'Flucti' if ENV['APPDATA']
        options << Pathname(ENV['HOME']) / '.flucti' if ENV['HOME']
        located = options.find { |dir| dir.directory? } || options.find { |dir| dir.dirname.directory? }
        located ||= Pathname(Dir.tmpdir) / 'flucti'
        located.mkpath
        located
      end
    end

    def data_store
      @data_store ||= store_dir / 'parameters.yml'
    end

    def fetch(key)
      cache[key.to_s]
    end

    def store(key, value)
      cache[key.to_s] = value
      data_store.open("w") { |f| f << YAML.dump(cache) }
    end

  private

    def cache
      @cache ||= (YAML.load_file(data_store) if data_store.exist?) || {}
    end
  end
end