# frozen_string_literal: true

# Released under the MIT License.
# Copyright, 2023, by Samuel Williams.

# require_relative 'address'
require 'uri'
require 'socket'

module IO::Endpoint
	Address = Addrinfo
	
	# Endpoints represent a way of connecting or binding to an address.
	class Generic
		def initialize(**options)
			@options = options.freeze
		end
		
		def with(**options)
			dup = self.dup
			
			dup.options = @options.merge(options)
			
			return dup
		end
		
		attr_accessor :options
		
		# @return [String] The hostname of the bound socket.
		def hostname
			@options[:hostname]
		end
		
		# If `SO_REUSEPORT` is enabled on a socket, the socket can be successfully bound even if there are existing sockets bound to the same address, as long as all prior bound sockets also had `SO_REUSEPORT` set before they were bound.
		# @return [Boolean, nil] The value for `SO_REUSEPORT`.
		def reuse_port?
			@options[:reuse_port]
		end
		
		# If `SO_REUSEADDR` is enabled on a socket prior to binding it, the socket can be successfully bound unless there is a conflict with another socket bound to exactly the same combination of source address and port. Additionally, when set, binding a socket to the address of an existing socket in `TIME_WAIT` is not an error.
		# @return [Boolean] The value for `SO_REUSEADDR`.
		def reuse_address?
			@options[:reuse_address]
		end
		
		# Controls SO_LINGER. The amount of time the socket will stay in the `TIME_WAIT` state after being closed.
		# @return [Integer, nil] The value for SO_LINGER.
		def linger
			@options[:linger]
		end
		
		# @return [Numeric] The default timeout for socket operations.
		def timeout
			@options[:timeout]
		end
		
		# @return [Address] the address to bind to before connecting.
		def local_address
			@options[:local_address]
		end
		
		# Endpoints sometimes have multiple paths.
		# @yield [Endpoint] Enumerate all discrete paths as endpoints.
		def each
			return to_enum unless block_given?
			
			yield self
		end
		
		# Accept connections from the specified endpoint.
		# @param backlog [Integer] the number of connections to listen for.
		def accept(backlog: Socket::SOMAXCONN, &block)
			bind do |server|
				server.listen(backlog) if backlog
				
				while true
					socket, address = server.accept
					
					Fiber.schedule do
						yield accepted(socket), address
					end
				end
			end
		end
		
		# Map all endpoints by invoking `#bind`.
		# @yield the bound wrapper.
		def bound
			wrappers = []
			
			self.each do |endpoint|
				wrapper = endpoint.bind
				wrappers << wrapper
				
				yield wrapper
			end
			
			return wrappers
		ensure
			wrappers.each(&:close) if $!
		end
		
		# Create an Endpoint instance by URI scheme. The host and port of the URI will be passed to the Endpoint factory method, along with any options.
		#
		# @param string [String] URI as string. Scheme will decide implementation used.
		# @param options keyword arguments passed through to {#initialize}
		#
		# @see Endpoint.ssl ssl - invoked when parsing a URL with the ssl scheme "ssl://127.0.0.1"
		# @see Endpoint.tcp tcp - invoked when parsing a URL with the tcp scheme: "tcp://127.0.0.1"
		# @see Endpoint.udp udp - invoked when parsing a URL with the udp scheme: "udp://127.0.0.1"
		# @see Endpoint.unix unix - invoked when parsing a URL with the unix scheme: "unix://127.0.0.1"
		def self.parse(string, **options)
			uri = URI.parse(string)
			
			self.public_send(uri.scheme, uri.host, uri.port, **options)
		end
		
		protected
		
		def accepted(socket)
			socket
		end
	end
end