module Vx
  module Builder
    class ScriptBuilder

      class Nodejs < Base

        DEFAULT_NODE = '0.10'
        NPM_PACKAGES = '~/.npm-packages'
        BOWER_COMPONENTS = '~/.bower_components'

        def call(env)
          if enabled?(env)

            vxvm_install(env, 'nodejs', node_version(env))

            do_cache_key(env) do |i|
              i << "nodejs-#{node_version env}"
            end

            do_announce(env) do |i|
              i << trace_sh_command("node --version")
              i << trace_sh_command("npm --version")
            end

            do_before_install(env) do |i|
              i << "mkdir -p #{NPM_PACKAGES}"
              i << "mkdir -p #{BOWER_COMPONENTS}"
              i << trace_sh_command("npm config set prefix=#{NPM_PACKAGES}")
              i << "test -f .bowerrc || (" + trace_sh_command("export bower_directory=#{BOWER_COMPONENTS}") + ")"
              i << "export PATH=$PATH:#{NPM_PACKAGES}/bin"
            end

            do_install(env) do |i|
              i << trace_sh_command("npm install")
            end

            do_script(env) do |i|
              i << trace_sh_command("npm test")
            end

            do_cached_directories(env) do |i|
              i << NPM_PACKAGES
              i << BOWER_COMPONENTS
            end
          end

          app.call(env)
        end

        private

          def enabled?(env)
            env.source.node_js.first || env.source.language == 'node_js'
          end

          def node_version(env)
            env.source.node_js.first || DEFAULT_NODE
          end

      end
    end
  end
end