local enet = require"enet"
local json = require"common.dkjson"
local unpack = unpack or table.unpack

math.randomseed(os.time())

local host = enet.host_create("*:8473")
print(host:get_socket_address())

-- sequential list of all players
local playerlist = {}
local nextid = 1

-- this is maybe suboptimal
-- but it is simplest for now
local function player_by_id(id)
	for i,pl in ipairs(playerlist) do
		if pl.id == id then return pl, i end
	end
	return nil
end
local function player_by_peer(peer)
	for i,pl in ipairs(playerlist) do
		if pl.peer == peer then return pl, i end
	end
	return nil
end

local function random_color()
	return {math.random(),math.random(),math.random()}
end
local function make_player(peer)
	local p = {pos={0,0},color=random_color(),peer=peer,id=nextid}
	nextid = nextid + 1
	return p
end

local function player_info_part(player)
	return {
		id=player.id,
		x=player.pos[1],
		y=player.pos[2],
		color=player.color,
	}
end
local function player_join_packet(player)
	return json.encode{t="join",pl=player_info_part(player)}
end
local function player_you_packet(player)
	return json.encode{t="you",pl=player_info_part(player)}
end
local function player_leave_packet(player)
	return json.encode{t="leave",id=player.id}
end
local function player_move_packet(player,x,y)
	return json.encode{t="move",id=player.id,x=x,y=y}
end

while true do
	local ev = host:service(100)
	if ev then
		if ev.type == "connect" then
			local player = make_player(ev.peer)
			table.insert(playerlist,player)
			print("connect",player.peer,player.id)
			player.peer:send(player_you_packet(player))

			for i,otherplayer in ipairs(playerlist) do
				if otherplayer ~= player then
					-- tell new player about each other player
					player.peer:send(player_join_packet(otherplayer))
					-- tell each other player about new player
					otherplayer.peer:send(player_join_packet(player))
				end
			end
		elseif ev.type == "disconnect" then
			local player, idx = player_by_peer(ev.peer)
			if not player then error("sneeze "..ev.peer) end
			print("disconnect",player.peer,player.id)
			table.remove(playerlist,idx)
			for i,otherplayer in ipairs(playerlist) do
				otherplayer.peer:send(player_leave_packet(player))
			end
		elseif ev.type == "receive" then
			local player = player_by_peer(ev.peer)
			if not player then error("sneezey "..ev.peer) end
			local j = json.decode(ev.data)
			local op = j.t
			if op == "ppos" then
				local x,y = j.x,j.y
				player.pos[1] = x
				player.pos[2] = y
				print(player.id,"-->",player.pos[1],player.pos[2])
				for i,otherplayer in ipairs(playerlist) do
					if otherplayer ~= player then
						otherplayer.peer:send(player_move_packet(player,x,y))
					end
				end
			end

		end
		-- for k,v in pairs(ev) do io.write(tostring(k),":",tostring(v)," ") end
		-- print()
	end
end