# ---- requirements
$LOAD_PATH << File.expand_path("../lib", File.dirname(__FILE__))
require 'rubygems'

FAKE_RAILS_ROOT = '/tmp/pspecs/fixtures'

require 'parallel_specs'
require 'parallel_cucumber'

def mocked_process
  open('|cat /dev/null')
end

def size_of(group)
  group.inject(0) { |sum, test| sum += File.stat(test).size }
end

# Uses /tmp/parallel_tests/application as the cwd so we can create and remove
# files as we want to. After execution it changes cwd back to the original one.
def use_temporary_directory_for
  require 'fileutils'

  dir = File.join("/tmp", "parallel_tests")
  new_dir = File.join(dir, "application")

  begin
    # just in case the temporary dir already exists
    FileUtils.rm_rf(dir) if File.exists?(dir)

    # create the temporary directory
    FileUtils.mkdir_p(new_dir)

    # chdir changes cwd back to the original one after it is done
    Dir.chdir(new_dir) do
      yield
    end
  ensure
    FileUtils.rm_rf(dir) if File.exists?(dir)
  end
end

def test_tests_in_groups(klass, folder, suffix)
  test_root = "#{FAKE_RAILS_ROOT}/#{folder}"

  describe :tests_in_groups do
    before :all do
      system "rm -rf #{FAKE_RAILS_ROOT}; mkdir -p #{test_root}/temp"

      @files = [0,1,2,3,4,5,6,7].map do |i|
        size = 99
        file = "#{test_root}/temp/x#{i}#{suffix}"
        File.open(file, 'w') { |f| f.puts 'x' * size }
        file
      end

      @log = klass.runtime_log
      `mkdir -p #{File.dirname(@log)}`
      `rm -f #{@log}`
    end

    after :all do
      `rm -f #{klass.runtime_log}`
    end

    it "groups when given an array of files" do
      list_of_files = Dir["#{test_root}/**/*#{suffix}"]
      found = klass.with_runtime_info(list_of_files)
      found.should =~ list_of_files.map{ |file| [file, File.stat(file).size]}
    end

    it "finds all tests" do
      found = klass.tests_in_groups(test_root, 1)
      all = [ Dir["#{test_root}/**/*#{suffix}"] ]
      (found.flatten - all.flatten).should == []
    end

    it "partitions them into groups by equal size" do
      groups = klass.tests_in_groups(test_root, 2)
      groups.map{|g| size_of(g)}.should == [400, 400]
    end

    it 'should partition correctly with a group size of 4' do
      groups = klass.tests_in_groups(test_root, 4)
      groups.map{|g| size_of(g)}.should == [200, 200, 200, 200]
    end

    it 'should partition correctly with an uneven group size' do
      groups = klass.tests_in_groups(test_root, 3)
      groups.map{|g| size_of(g)}.should =~ [300, 300, 200]
    end

    def setup_runtime_log
      File.open(@log,'w') do |f|
        @files[1..-1].each{|file| f.puts "#{file}:#{@files.index(file)}"}
        f.puts "#{@files[0]}:10"
      end
    end

    it "partitions by runtime when runtime-data is available" do
      klass.stub!(:puts)
      setup_runtime_log

      groups = klass.tests_in_groups(test_root, 2)
      groups.size.should == 2
      # 10 + 1 + 3 + 5 = 19
      groups[0].should == [@files[0],@files[1],@files[3],@files[5]]
      # 2 + 4 + 6 + 7 = 19
      groups[1].should == [@files[2],@files[4],@files[6],@files[7]]
    end

    it "alpha-sorts partitions when runtime-data is available" do
      klass.stub!(:puts)
      setup_runtime_log

      groups = klass.tests_in_groups(test_root, 2)
      groups.size.should == 2

      groups[0].should == groups[0].sort
      groups[1].should == groups[1].sort
    end

    it "partitions by round-robin when not sorting" do
      files = ["file1.rb", "file2.rb", "file3.rb", "file4.rb"]
      klass.should_receive(:find_tests).and_return(files)
      groups = klass.tests_in_groups(files, 2, :no_sort => true)
      groups[0].should == ["file1.rb", "file3.rb"]
      groups[1].should == ["file2.rb", "file4.rb"]
    end

    it "alpha-sorts partitions when not sorting by runtime" do
      files = %w[q w e r t y u i o p a s d f g h j k l z x c v b n m]
      klass.should_receive(:find_tests).and_return(files)
      groups = klass.tests_in_groups(files, 2, :no_sort => true)
      groups[0].should == groups[0].sort
      groups[1].should == groups[1].sort
    end
  end
end