#!/usr/bin/ruby

# main.rb

require 'socket'
require 'fileutils'
require 'pathname'
require 'erb'

Root = '.'
Port = 8080

class HttpResponse
	def self.process_erb(resp)
		unless resp.ext === ".erb"
			resp.data = resp.lazy.read
			return
		end

		books = Dir["*"]

		template = ERB.new resp.lazy.read
		resp.data = template.result(binding)
		return
	end

	def self.connection(str)
		"Connection: #{str}"
	end

	def self.content_length(resp)
		"Content-Length: #{resp.length}"
	end

	def self.content_type(resp)
		ctype = {
			".png" => "image/png",
			".txt" => "text/plain",
			".html" => "text/html",
			".erb" => "text/html",
			".css" => "text/css",
			".mp3" => "audio/mpeg",
			".ttf" => "font/ttf",
			".mp4" => "video/mp4",
			".pdf" => "application/pdf",
			".webp" => "image/webp"
		}

		"Content-Type: #{ctype[resp.ext]}"
	end

	def self.build(resp)
		resp.route

		if resp.not_found?
			return "HTTP/1.1 404 NOT FOUND\r\n"
		end

		process_erb(resp)

		headers = [
			content_length(resp),
			content_type(resp),
		].join("\r\n")
		
		puts headers

		return "HTTP/1.1 200 OK\r\n#{headers}\r\n\r\n#{resp.data}"
	end
end

class HttpRouter
	attr_reader :ext
	attr_reader :length
	attr_accessor :data
	attr_reader :lazy

	def initialize(path)
		@path = Pathname.new(path)
		@ext = File.extname(path)
		@not_found = false
		@data
	end

	def route
		puts @path

		case @path
		when Pathname.new("/")
			@path = Pathname.new("/index.erb")
			return route
		else
			if File.exist? @path.basename
				@lazy = File.open(@path.basename)
				@length = File.size(@path.basename)
				@ext = File.extname(@path)
			else
				@not_found = true
			end
		end
	end

	def not_found?
		@not_found
	end
end

class HttpServer
	def initialize(port)
		@server = TCPServer.new port
	end

	def accept_connection
		while session = @server.accept
			request = session.gets

			verb, path, protocol = request.split(' ')
			if protocol === 'HTTP/1.1'
				resp = HttpRouter.new(path)
				session.puts HttpResponse.build(resp)
			else
				session.puts 'Connection Refused'
			end

			session.close
		end
	end
end

server = HttpServer.new Port
server.accept_connection