-- Handles the bridge to javascript to do peer-to-peer connections


log = require("log")
net = {}

net.initalize = () ->
	am.eval_js(require("js_bridge"))

net.call = (method, args) ->
	print("About to eval")
	result = am.eval_js("window.PEER." .. method .. "(" .. am.to_json(args) .. ")")
	print("Done evaling")
	result

net.pull = () ->
	messages = am.eval_js("window.PEER.message_queue")
	am.eval_js("window.PEER.message_queue = []")
	messages

callbacks = {}
peers = {}
connections = {}

class Connection
	new: (source, dest) =>
		@source = source
		@dest = dest
	on: (event, callback) =>
		newid = #callbacks + 1
		callbacks[newid] = callback
		net.call("conn_on", {name: @source, id: @dest, e: event, message: newid})
	send: (msgname, msg) =>
		net.validate(msgname, msg)
		net.call("send",{name: @source, id: @dest, data: msg})

class Peer
	new: (id) =>
		net.call("create",{name: id})
		if id
			@id = id
			peers[id] = @
	on: (event, callback) =>
		newid = #callbacks + 1
		callbacks[newid] = callback
		net.call("on",{name: @id, message:newid, e: event})
	
	connect: (id, options) =>
		conn = net.call("connect", {name: @id, id: id})
		log.info("Got connection: " .. tostring(conn), {"net"})
		Connection(conn[1],conn[2])


net.Peer = Peer

-- A fake peer for testing
fakepeers = {}
fakeconnections = {}
fakecallbacks = {}
channel = require("channel")

class FakePeer
	new: (id) =>
		if id
			@id = id
			fakepeers[id] = @
	on: (event, callback) =>
		newid = #fakecallbacks + 1
		fakecallbacks[newid] = callback
	
	connect: (id, options) =>
		conn = channel.FaultyChannel({
			avg_latency: 200
			latency_std: 100
			loss: 0.1
		})
		conn


messages = {}
formatcache = {}
message_callbacks = {}
net.register_message = (name, format) ->
	assert(type(format) == "table", "Format must be a table")
	format.required = format.required or {}
	format.optional = format.optional or {}
	assert(next(format.required) or next(format.optional), "No fields found")
	for set in *({format.required, format.optional})
		for field, type_ in pairs(format.required)
			if type(type_) == "string"
				key = string.format("%s\0%s\0%s",name,field,type_)
				if not formatcache[key]
					formatcache[key] = (any) ->
						assert(type(any) == type_, string.format("In message %q %q must be a %q, but was a %q", name, field, type_, type(any)))
				set[field] = formatcache[key]
	messages[name] = format
	message_callbacks[name] = {}

net.validate = (name, message) ->
	assert(type(message) == "table", "Message must be a table")
	format = messages[name]
	required = {}
	for field, validate in pairs(format.required)
		required[field] = validate
	for field, value in pairs(message)
		if format.required[field]
			required[field](value)
			required[field] = nil
		if format.optional[field]
			format.optional[field](value)
	missing = next(required)
	if missing
		error("Missing required field: " .. missing)
	true

net.listen = (name, callback, id) ->
	id = id or {}
	message_callbacks[name] = message_callbacks[name] or {}
	message_callbacks[name][id] = callback
	id

net.defen = (name, id) ->
	message_callbacks[name][id] = nil

rewrite_events = {
	connection: (message) ->
		message.data.data = Connection(message.data.data[1], message.data.data[2])
}

net.pump = () ->
	msg_ = net.pull!
	log.info("Processing " .. tostring(#msg_) .. " messages", {"net"})
	for message in *msg_
		log.info(tostring(message), {"net", message.data.peer})
		if rewrite_events[message.data.e]
			log.info("Rewriting data due to " .. message.data.e .. " event", {"net", message.data.peer})
			rewrite_events[message.data.e](message)
			log.info(tostring(message), {"net", message.data.peer})
		peer = peers[message.data.peer]
		assert(peer, "Failed to find peer:" .. message.data.peer)
		callback = callbacks[message.message]
		assert(callback, "Failed to find callback " .. message.message .. " on peer " .. message.data.peer)
		callback(peer,message.data)

net.peers = () ->
	peers

net