module Utopia::Project

def self.call(builder, root = Dir.pwd, locales: nil)

@parameter locales [Array(String)] an array of locales to support, e.g. `['en', 'ja']`.
@parameter root [String] The file-system root path of the project/gem.
@parameter builder [Rack::Builder]

Appends a project application to the rack builder. 
def self.call(builder, root = Dir.pwd, locales: nil)
	if UTOPIA.production?
		# Handle exceptions in production with a error page and send an email notification:
		builder.use Utopia::Exceptions::Handler
		builder.use Utopia::Exceptions::Mailer
	else
		# We want to propate exceptions up when running tests:
		builder.use Rack::ShowExceptions unless UTOPIA.testing?
	end
	
	# We serve static files from the project root:
	builder.use Utopia::Static, root: root
	
	builder.use Utopia::Static, root: PUBLIC_ROOT
	
	builder.use Utopia::Redirection::Rewrite, {
		'/' => '/index'
	}
	
	builder.use Utopia::Redirection::DirectoryIndex
	
	builder.use Utopia::Redirection::Errors, {
		404 => '/errors/file-not-found'
	}
	
	if locales
		builder.use Utopia::Localization,
			default_locale: locales.first,
			locales: locales
	end
	
	builder.use Utopia::Controller, root: PAGES_ROOT
	
	cache_root = File.expand_path("_gallery", root)
	
	builder.use Utopia::Content, root: PAGES_ROOT, namespaces: {
		# 'gallery' => Utopia::Gallery::Tags.new
	}
	
	builder.run lambda { |env| [404, {}, []] }
end