local skynet = require "skynet"
require "skynet.manager"
local socket = require "skynet.socket"
local websocket = require "http.websocket"
local socketdriver = require "skynet.socketdriver"

local jmutil = require "jmutil"

local WATCHDOG = nil
local mapFd = {} -- fd -> connection : { fd , client, agent , ip, mode }

local clientCount = 0
local MAX_CLIENT = 1024 -- max client
local IS_NODELAY = false

-- fd解绑agent
local function l_unband_agent(c)
    if c.agent then
        c.agent = nil
        c.client = nil
    end
end

local function l_close_fd(fd)
    local c = mapFd[fd]
    if c then
        l_unband_agent(c)
        mapFd[fd] = nil
        clientCount = clientCount - 1
    end
end

local handler = {}
-- 接受链接
function handler.connect(fd)
    local addr = websocket.addrinfo(fd)
    skynet.error(string.format("ws connect fd[%s] from[%s] ", tostring(fd), tostring(addr)))
    if clientCount >= MAX_CLIENT then
        -- 超出最大承载玩家数
        socketdriver.close(fd)
        skynet.error(string.format("超出最大承载玩家数 MAX_CLIENT[%s]", tostring(MAX_CLIENT)))
        return
    end
    if IS_NODELAY then
        socketdriver.nodelay(fd)
    end

    clientCount = clientCount + 1
    local c = {
        fd = fd,
        ip = addr
    }
    mapFd[fd] = c

    skynet.send(WATCHDOG, "lua", "socket", "open", fd, addr)
end

function handler.handshake(fd, header, url)
end

-- 接收消息
function handler.message(fd, msg)
    -- skynet.error("message ws ping from: " .. tostring(fd), msg.."\n")
    if #msg == 0 then
        return
    end
    --  msg is string
    local data, sz = jmutil.str2lightuserdata(msg)

    -- recv a package, forward it
    local c = mapFd[fd]
    local agent = c and c.agent
    if agent then
        skynet.redirect(agent, c.client, "client", fd, data, sz)
    else
        -- 首次必须鉴权
        skynet.send(WATCHDOG, "lua", "socket", "data", fd, data, sz)
    end
end

function handler.ping(fd)
    skynet.error("ws ping from: " .. tostring(fd) .. "\n")
end

function handler.pong(fd)
    skynet.error("ws pong from: " .. tostring(fd))
end

function handler.close(fd, code, reason)
    skynet.error("ws close from: " .. tostring(fd), code, reason)
    l_close_fd(fd)
    skynet.send(WATCHDOG, "lua", "socket", "close", fd)
end

function handler.error(fd)
    skynet.error("ws error from: " .. tostring(fd))
    l_close_fd(fd)
    skynet.send(WATCHDOG, "lua", "socket", "error", fd)
end

function handler.warning(fd, size)
    skynet.send(WATCHDOG, "lua", "socket", "warning", fd, size)
end

local root = {}

-- 开始监听链接
function root.open(source, conf)
    WATCHDOG = conf.watchdog or source

    if conf.maxclient then
        MAX_CLIENT = conf.maxclient
    end
    IS_NODELAY = conf.nodelay

    -- 打开监听链接端口
    local address = "0.0.0.0"
    local port = assert(conf.wsPort)
    local protocol = conf.protocol or "ws"
    local fd = socket.listen(address, port)

    skynet.error(
        string.format("Listen websocket fd[%s] port[%s] protocol[%s]", tostring(fd), tostring(port), tostring(protocol))
    )

    -- 开始接受链接
    socket.start(
        fd,
        function(fd, addr)
            -- skynet.error(string.format("accept client socket_fd: %s addr:%s", fd, addr))
            websocket.accept(fd, handler, protocol, addr)
        end
    )
end

-- fd已经绑定agent
function root.fd_band_agent(source, fd, client, address)
    if not mapFd[fd] then
        return false
    end
    local c = assert(mapFd[fd])
    l_unband_agent(c)

    c.client = client or 0
    c.agent = address or source

    return true
end

-- 向fd回应消息
function root.send_to_client(source, fd, msg)
    if msg == nil then
        return
    end
    websocket.write(fd, msg, "binary")
end

-- 断开链接
function root.kick(source, fd)
    websocket.close(fd)
end

-- 注册接收skynet协议列表
skynet.register_protocol {
    name = "client",
    id = skynet.PTYPE_CLIENT
}

skynet.start(
    function()
        skynet.dispatch(
            "lua",
            function(session, source, cmd, ...)
                local f = root[cmd]
                if not f then
                    skynet.error("wsGate can't dispatch cmd " .. (cmd or nil))
                    return
                end
                if session == 0 then
                    f(source, ...)
                else
                    skynet.ret(skynet.pack(f(source, ...)))
                end
            end
        )

        skynet.register(".ws_gate")
    end
)