Convert railrouter to module

Trimmed whitespace, split functions into a separate module.

src/railrouter/modules/railrouter.lua

@@ -0,0 +1,258 @@
+package.path = package.path .. ";/modules/?;/modules/?.lua;/modules/?/init.lua"
+local log = require("log")
+local events = require("events")
+local net = require("net")
+local dns = require("dns")
+local serializer = require("serializer")
+local railnetwork = require("railnetwork")
+local autoupdater = require("autoupdater")
+local railrouter = {}
+
+function railrouter.getStationComputerId(station, feature)
+	local station = stations[station]
+	if station == nil then
+		return nil
+	end
+	local featureConfig = station.features[feature]
+	if featureConfig == nil then
+		return nil
+	end
+	return featureConfig.computerId
+end
+
+function railrouter.notifyNewRequest(request)
+	print(string.format("Sending new %s request to station %i", request.class, request.source))
+	local computerId = railrouter.getStationComputerId(request.source, request.class)
+	if computerId == nil then
+		log.err(string.format("Sending request to station %i but %s computer ID not found; discarding request", request.source, request.class))
+		return
+	end
+	net.sendMessage(computerId, "newRequest", request)
+end
+
+function railrouter.mergeTables(a, b)
+	for key, value in pairs(b) do
+		if a[key] == nil or type(a[key]) ~= "table" or type(value) ~= "table" then
+			a[key] = value
+		else
+			railrouter.mergeTables(a[key], value)
+		end
+	end
+end
+
+function railrouter.updateStation(station)
+	log.info(string.format("Updating station %i", station.stationId))
+	if stations[station.stationId] == nil then
+		stations[station.stationId] = {}
+	end
+	railrouter.mergeTables(stations[station.stationId], station)
+	railrouter.addStationToNetwork(station)
+	railrouter.stationsChanged()
+end
+
+function railrouter.stationsChanged()
+	serializer.writeToFile("stations", stations)
+
+	for id in pairs(stations) do
+		local computerId = railrouter.getStationComputerId(id, "passenger")
+		if computerId ~= nil then
+			log.info(string.format("Sending station update to %i at station %i", computerId, id))
+			net.sendMessage(computerId, "stationUpdate", stations)
+		end
+	end
+end
+
+function railrouter.sendStationList(_, sender)
+	log.info(string.format("Sending station list to %i", sender))
+	net.sendMessage(sender, "stationUpdate", stations)
+end
+
+function railrouter.removeStation(station)
+	log.info(string.format("Removing station %i", station.stationId))
+	stations[station.stationId] = nil
+	network:removeNode(railrouter.getStationNode(station.stationId, false))
+	network:removeNode(railrouter.getStationNode(station.stationId, true))
+	railrouter.stationsChanged()
+end
+
+function railrouter.validateTrip(trip)
+	if trip.origin and trip.destination then
+		local routes = network:findRoutes(trip)
+		if next(routes) then
+			trip.routes = routes
+			return true
+		end
+        return nil, string.format("No routes exist between origin %s and destination %s; did you misconfigure a switch or station?", railnetwork.formatLocation(trip.origin), railnetwork.formatLocation(trip.destination))
+	end
+	-- We can only check whether the destination is valid.
+	return network:findClosestNode(trip.destination)
+end
+
+function railrouter.checkTrip(trip)
+	log.info(string.format("New trip: %s at %s departing for %s", trip.type, railnetwork.formatLocation(trip.origin), railnetwork.formatLocation(trip.destination)))
+
+	local result, tripError = railrouter.validateTrip(trip)
+	if result then
+		net.sendMessage(trip.computerId, "allowDeparture", trip)
+	else
+		log.warn(string.format("Rejecting trip request: %s", tripError))
+		trip.rejectionReason = tripError
+		net.sendMessage(trip.computerId, "rejectDeparture", trip)
+	end
+end
+
+function railrouter.registerTrip(trip)
+	log.info(string.format("Departed: %s at %s in %s departing for %s", trip.type, railnetwork.formatLocation(trip.origin), trip.minecartName, railnetwork.formatLocation(trip.destination)))
+
+	trips[trip.minecartName] = trip
+	serializer.writeToFile("trips", trips)
+end
+
+function railrouter.minecartDetected(detection)
+	log.info(string.format("Minecart detected: %s at %s", detection.minecartName, railnetwork.formatLocation(detection.location)))
+
+	local trip = trips[detection.minecartName]
+	if trip == nil then
+		log.warn(string.format("No trip active for %s; ignoring detection", detection.minecartName))
+		return
+	end
+
+	if railnetwork.locationsMatch(trip.destination, detection.location) then
+		log.info(string.format("Trip to %s completed for %s", railnetwork.formatLocation(trip.destination), detection.minecartName))
+		trips[detection.minecartName] = nil
+		serializer.writeToFile("trips", trips)
+		return
+	end
+
+	trip.lastKnownLocation = detection.location
+	serializer.writeToFile("trips", trips)
+
+	if detection.switchId == nil then
+		-- There's nothing to do here if this location is not a switch.
+		return
+	end
+
+	local switch = switches[detection.switchId]
+	if switch == nil or switch.computerId == nil then
+		log.warn(string.format("Ignoring detection: Detection at switch %i, which was not found", detection.switchId))
+		return
+	end
+
+	local path, pathError = network:findRoute({origin = detection.location, destination = trip.destination, tags = trip.tags})
+	if not path then
+		log.warn(string.format("Ignoring detection: %s", pathError))
+		return
+	end
+
+	local edge = path.edges[1]
+	if edge == nil then
+		log.warn(string.format("Ignoring detection: Path to destination %s is empty", railnetwork.formatLocation(trip.destination)))
+		return
+	end
+
+	local switchState = edge.edge.switchState or false
+	log.info(string.format("Setting switch %i to %s", detection.switchId, tostring(switchState)))
+	net.sendMessage(switch.computerId, "setSwitch", {state = switchState})
+end
+
+function railrouter.switchOnline(switch)
+	log.info(string.format("Switch %i online", switch.id))
+	switches[switch.id] = switch
+	serializer.writeToFile("switches", switches)
+	railrouter.addSwitchToNetwork(switch)
+end
+
+function railrouter.switchOffline(switch)
+	log.info(string.format("Switch %i offline", switch.id))
+	switches[switch.id] = nil
+	serializer.writeToFile("switches", switches)
+	network:removeNode(railrouter.getSwitchNode(switch.id))
+end
+
+function railrouter.getStationNode(id, departing)
+	local nodeType = "arrive"
+	if departing then
+		nodeType = "depart"
+	end
+	return string.format("S%i-%s", id, nodeType)
+end
+
+function railrouter.getSwitchNode(id)
+	return string.format("T%i", id)
+end
+
+function railrouter.getSwitchConnection(location, switchState)
+	if location then
+		return {
+			location = location.location or location, -- For backwards compatibility with older switches
+			switchState = switchState,
+			distance = location.distance,
+			tags = location.tags,
+		}
+	end
+end
+
+function railrouter.addSwitchToNetwork(switch)
+	if switch.continuesTo and switch.location.direction then
+		error(string.format("Switch %i defines both continuesTo and location.direction; drop one of these to resolve the conflict", switch.id))
+	end
+	if not switch.divergesTo then
+		error(string.format("Switch %i does not define divergesTo", switch.id))
+	end
+	network:addNode(railrouter.getSwitchNode(switch.id), {
+		location = switch.location,
+		connections = {railrouter.getSwitchConnection(switch.divergesTo, true), railrouter.getSwitchConnection(switch.continuesTo, false)},
+	})
+end
+
+function railrouter.addStationToNetwork(station)
+	if not station.features.passenger then
+		return
+	end
+	if station.features.passenger.cartsIn then
+		network:addNode(railrouter.getStationNode(station.stationId, false), {location = station.features.passenger.cartsIn.location})
+	end
+	if station.features.passenger.cartsOut then
+		network:addNode(railrouter.getStationNode(station.stationId, true), {location = station.features.passenger.cartsOut.location})
+	end
+end
+
+function railrouter.buildRailNetwork()
+	network = railnetwork.new()
+	for _, switch in pairs(switches) do
+		railrouter.addSwitchToNetwork(switch)
+	end
+	for _, station in pairs(stations) do
+		railrouter.addStationToNetwork(station)
+	end
+	for id, line in pairs(lines) do
+		network:addLine(id, line)
+	end
+end
+
+function railrouter.onStartup()
+	trips = serializer.readFromFile("trips")
+	switches = serializer.readFromFile("switches")
+	stations = serializer.readFromFile("stations")
+	lines = serializer.readFromFile("lines")
+	railnetwork.buildRailNetwork()
+	net.registerMessageHandler("newRequest", railnetwork.notifyNewRequest)
+	net.registerMessageHandler("stationOnline", railnetwork.updateStation)
+	net.registerMessageHandler("stationOffline", railnetwork.removeStation)
+	net.registerMessageHandler("newTrip", railnetwork.checkTrip)
+	net.registerMessageHandler("tripDeparted", railnetwork.registerTrip)
+	net.registerMessageHandler("minecartDetected", minecartDetected)
+	net.registerMessageHandler("switchOnline", railnetwork.switchOnline)
+	net.registerMessageHandler("switchOffline", railnetwork.switchOffline)
+	net.registerRawMessageHandler("getStations", railnetwork.sendStationList)
+	autoupdater.initialize()
+
+	dofile("config")
+	log.info(string.format("RailRouterOS: Listening on %s...", net.openModem(config.modem)))
+	dns.register("railrouter")
+
+	events.runMessageLoop()
+end
+
+return railrouter
+