#!/usr/bin/env lua5.1
local enet = require("enet")
local util = require("util")
local common = require("common")

local host = enet.host_create("0.0.0.0:18252")

local game_to_peer = {}
local peer_to_game = {}

local function remove_game(peer)
    local game = peer_to_game[peer]
    if game then
        game_to_peer[game] = nil
        peer_to_game[peer] = nil
    end
end

local function handle(peer, pkt)
    if pkt.type == "match_register" then
        remove_game(peer)
        local game_id = util.rand_string(common.gameid_len)
        peer_to_game[peer] = game_id
        game_to_peer[game_id] = peer
        util.send(peer, { type = "server_match", game_id = util.base64_enc(game_id) })
        print(peer, "registered game")
    elseif pkt.type == "match_join" then
        local game_id = type(pkt.game_id) == "string" and util.base64_dec(pkt.game_id)
        if game_id then
            local server = game_id and game_to_peer[game_id]
            if server then
                util.send(server, { type = "server_join", peer_addr = tostring(peer) })
                util.send(peer, { type = "client_join", peer_addr = tostring(server) })
                print(peer, "joined game", server)
            else
                util.send(peer, { type = "client_join_fail" })
                print(peer, "failed to join game")
            end
        end
    else
        print("invalid pkt type")
    end
end

while true do
    local event = host:service(100)
    while event do
        if event.type == "receive" then
            local pkt = util.json_dec(event.data)
            if pkt then
                handle(event.peer, pkt)
            end
        elseif event.type == "connect" then
            print(event.peer, "connected")
        elseif event.type == "disconnect" then
            remove_game(event.peer)
            print(event.peer, "disconnected")
        end
        event = host:service()
    end
end