#!/usr/bin/env ruby
require 'unicorn-cuba-base'
require 'base64'

$LOAD_PATH.unshift(File.join(File.dirname(__FILE__), '..', 'lib'))

Application.new('httpimagestore', port: 3000, processor_count_factor: 2) do
	cli do
		description 'HTTP based image storage and thumbnailer'
		argument :config,
			cast: Pathname,
			description: 'configuration file path'
		version((Pathname.new(__FILE__).dirname + '..' + 'VERSION').read)
	end

	settings do |settings|
		Controller.settings[:config_file] = settings.config
	end

	main do |settings|
		require 'httpimagestore/error_reporter'

		class HTTPImageStore < Controller
			include PerfStats
			extend Stats
			def_stats(
				:workers,
				:total_requests,
				:total_errors
			)

			raindrops_stats = Raindrops::Middleware::Stats.new
			self.use Raindrops::Middleware, stats: raindrops_stats

			StatsReporter << HTTPImageStore.stats
			StatsReporter << raindrops_stats
			StatsReporter << Plugin::ResponseHelpers.stats

			self.define do
				HTTPImageStore.stats.incr_total_requests
				on error? do
					HTTPImageStore.stats.incr_total_errors
					run ErrorReporter
				end

				on 'stats' do
					run StatsReporter
				end

				on 'health_check' do
					log.debug "health_check"
					if client = env['app.configuration'].thumbnailer
						# 8x8 PNG
						data = Base64.decode64('iVBORw0KGgoAAAANSUhEUgAAAAQAAAAECAIAAAAmkwkpAAAAI0lEQVQI1z3KMQoAMAyAwEv//2c7pFQQHISqssXaQWby+NsFYkkV7w+CVgAAAAAASUVORK5CYII=')

						begin
							thumbnail = client.thumbnail(data, 'fit', 4, 4, 'jpeg')
							unless thumbnail.data.length > 300 and thumbnail.data.include? 'JFIF'
								write_plain 502, 'bad image data returned from thumbnailer'
								halt res.finish
							end
						rescue Errno::ECONNREFUSED => error
							write_error 502, error
							halt res.finish
						end
					end
					write_plain 200, 'HTTP Image Store OK'
				end

				log.debug{"got request: #{env["REQUEST_METHOD"]} #{env["REQUEST_URI"]}"}
				env['app.configuration'].handlers.each do |handler|
					log.debug{"trying handler: #{handler}"}
					on eval(handler.http_method), *handler.uri_matchers.map{|m| instance_eval(&m.matcher)} do |*args|
						log.debug{"matched handler: #{handler}"}
						log.with_meta_context api_method: handler.http_method.upcase, api_handler: handler.to_s do
							measure "handling request", handler.to_s do
								# map and decode matched URI segments
								matches = {}
								names = handler.uri_matchers
								.map do |matcher|
									matcher.names
								end
								.flatten

								fail "matched more arguments than named (#{args.length} for #{names.length})" if args.length > names.length
								fail "matched less arguments than named (#{args.length} for #{names.length})" if args.length < names.length

								names.zip(args)
								.each do |name, value|
									fail "name should be a symbol" unless name.is_a? Symbol
									matches[name] = URI.utf_decode(value)
								end

								# decode remaining URI components
								path = (env['PATH_INFO'][1..-1] || '').split('/').map do |part|
									URI.utf_decode(part)
								end.join('/')

								# query string already decoded by Rack
								query_string = req.GET

								# actual request URI
								request_uri = env['REQUEST_URI']
								request_headers = env.select{|k,v| k.start_with? 'HTTP_'}.map do |pair|
									[
										pair[0].sub(/^HTTP_/, '').gsub('_', '-'),
										pair[1]
									]
								end
								request_headers = Hash[request_headers]
								request_headers.delete('VERSION')

								body = measure "reading request body" do
									req.body.read
								end

								state = Configuration::RequestState.new(body, matches, path, query_string, request_uri, request_headers, memory_limit, env['xid'] || {})

								measure "validating request" do
									handler.validators.each do |validator|
										validator.realize(state) unless validator.respond_to? :excluded? and validator.excluded?(state)
									end
								end unless handler.validators.empty?
								measure "sourcing images" do
									handler.sources.each do |source|
										source.realize(state) unless source.respond_to? :excluded? and source.excluded?(state)
									end
								end
								measure "processing images" do
									handler.processors.each do |processor|
										processor.realize(state) unless processor.respond_to? :excluded? and processor.excluded?(state)
									end
								end unless handler.processors.empty?
								measure "storing images" do
									handler.stores.each do |store|
										store.realize(state) unless store.respond_to? :excluded? and store.excluded?(state)
									end
								end unless handler.stores.empty?
								measure "sending response" do
									handler.output.realize(state)
									instance_eval(&state.output_callback)
								end
							end
						end
					end
				end

				on root do
					write_plain 200, 'HTTP Image Store'
				end
			end
		end

		class Configurator
			def initialize(app, configuration)
				@app = app
				@configuration = configuration
			end

			def call(env)
				env['app.configuration'] = @configuration
				@app.call(env)
			end
		end

		require 'httpimagestore/configuration'

		# connect Scope tree with Controller logger
		Configuration::Scope.logger = Controller.logger_for(Configuration::Scope)

		# load builin supported set
		require 'httpimagestore/configuration/path'
		require 'httpimagestore/configuration/handler'
		require 'httpimagestore/configuration/thumbnailer'
		require 'httpimagestore/configuration/identify'
		require 'httpimagestore/configuration/file'
		require 'httpimagestore/configuration/output'
		require 'httpimagestore/configuration/s3'
		require 'httpimagestore/configuration/validate_hmac'

		HTTPImageStore.use Configurator, Configuration.from_file(settings.config)
		HTTPImageStore
	end

	after_fork do |server, worker|
		HTTPImageStore.stats.incr_workers
	end
end