require 'erb'
require 'fileutils'
require 'ostruct'
require 'chefspec'

module ChefSpec
  class Bootstrap

    def initialize(cookbooks_dir, spec_dir, template_file)
      @cookbooks_dir = cookbooks_dir
      @spec_dir = spec_dir
      @template_file = template_file
    end

    def setup
      if not Dir.exist?(@cookbooks_dir)
        abort "Unable to locate your cookbooks directory (#{@cookbooks_dir})"
      end

      if not @template_file
        @template_file = root.join('templates', 'default.erb')
      end

      if not File.exist?(@template_file)
        abort "Unable to locate template file (#{@template_file})"
      end
    end

    def generate
      setup()

      erb = ERB.new(File.read(@template_file))

      # begin
      #   require "#{@spec_dir}/spec_helper.rb"
      # rescue LoadError

      # end

      ::RSpec.configure { |config| config.cookbook_path = [@cookbooks_dir, 'cookbooks'] }

      Dir.glob("#{@cookbooks_dir}/*/recipes/*").each do |path|
        path, recipe_file = File.split(path)
        recipe = recipe_file.split('.')[0]
        cookbook = path.split(File::SEPARATOR)[1]

        filename = "#{@spec_dir}/#{cookbook}/#{recipe}_spec.rb"

        puts filename

        if File.exist?(filename)
          puts "    spec already exists. Skipping."
        else
          FileUtils.mkdir_p "#{@spec_dir}/#{cookbook}"

          puts "    executing recipe with ChefSpec..."
          chef_run = get_chef_run(cookbook, recipe)

          if chef_run
            puts "    execution suceeded. Creating spec file."
          else
            puts "    execution failed. Creating empty spec file."
          end

          resources = get_resources(chef_run)
          test_cases = generate_test_cases(resources)

          File.open(filename, "w") do |spec_file|
            spec_file.write(erb.result(binding))
          end
        end
      end
    end

    def root
      @root ||= Pathname.new(File.expand_path('../../', __FILE__))
    end

    def get_chef_run(cookbook, recipe)
      begin
        return ChefSpec::Runner.new.converge("#{cookbook}::#{recipe}")
      rescue
        return nil
      end
    end

    def get_resource_name(resource)
      return resource.name || resource.identity
    end

    def get_resources(chef_run)
      if chef_run
        return chef_run.resource_collection.all_resources
      else
        return []
      end
    end

    def generate_test_cases(resources)
      test_cases = []
      resources.each do |resource|
        verbs = resource.action
        if not verbs.respond_to?(:each)
          verbs = [verbs]
        end

        noun = resource.resource_name
        adjective = resource.name

        verbs.each do |verb|
          if not verb == :nothing
            test_cases.push({
              :it => "#{verb}s the #{adjective} #{noun}",
              :action => "#{verb}_#{noun}",
              :name => adjective
            })
          end
        end
      end
      return test_cases
    end
  end
end