#!/usr/bin/lua
-- miqos 主框架

local socket=require("socket")
local io=   require 'io'
local libunix= require 'socket.unix'
local json= require 'json'
local unsock=assert(libunix())

-- 单一流的设备，比如电视/盒子，用来做设备最低带宽预留
band_reserve_hosts={
    changed=true,
    ['video']={},
    ['other']={},
}

-- 特殊设备优先级
special_host_list={
    host={
    },
    changed=false,
}

require "miqos.common"
require "miqos.command"
--require "miqos.rule_by_flow"
require "miqos.rule_by_host"
require "miqos.rule_by_prio"
require "miqos.rule_by_service"

local QOS_CMD

--read args
QOS_VER='CTF'
if #arg >= 1 then
    if arg[1] == 'std' then
        QOS_VER='STD'
    elseif arg[1] == 'ctf' then
        QOS_VER='CTF'
    elseif arg[1] == 'fix' then
        QOS_VER='FIX'
    elseif arg[1] == 'hwqos' then
        QOS_VER='HWQOS'
    else
        QOS_VER='FIX'
        QOS_CMD=arg
    end
else
    clean_sock()
    logger(3,'======== Process Exit. =====')
    os.exit(0)
end

-----全局定义-----------------

g_group_def=nil
g_class_def={}

-- TODO: 暂时关闭，需要看测试结果
g_enable_stab=false

---
g_leaf_type='fq_codel'   --,sfq,fq_codel
--g_leaf_type='sfq'   --,sfq,fq_codel


function clean_sock()
    unsock:close()
    util.exec('rm -rf ' .. cfg.server.path)
end


-- 清除规则，并退出服务
function system_exit()
    cleanup_system()
    clean_sock()
    logger(3,'======== Process Exit. =====')
    os.exit(0)
end

-- 系统初始化
local function system_init()

    -- 将配置文件copy到tmp内存中,并初始化cursor
    if not cfg2tmp() then
        return false
    end

    -- 读取网络配置
    if not read_network_conf() then
        logger(3, 'failed to read network config!')
        return false
    end

    -- read_qos_config()

    -- SIGTERM to clear and exit
    px.signal(px.SIGTERM,
        function ()
            logger(3,'signal TERM to stop miqos.')
            system_exit()
        end)

    px.signal(px.SIGINT,
        function ()
            logger(3,'signal INT to stop miqos.')
            system_exit()
        end)

    return true
end

g_ifb_status=''
local function check_ifb_up()
    if QOS_VER == 'HWQOS' then
        return true
    end
    -- 如果ifb状态未UP,则尝试UP
    if g_ifb_status ~= UP then
        --check if dev ifb0 is up
        local ifb_up = '/usr/sbin/ip link set ifb0 up '
        local ifb_check = '/usr/sbin/ip link show ifb0 |grep "state DOWN"'
        local ret = util.exec(ifb_up)
        ret = util.exec(ifb_check)
        if ret == '' then
            g_ifb_status = UP
        else
            logger(3, 'ifb0 is not up, wait for next link up.')
            return false    -- 继续下一次set link up
        end
    end
    return true
end

-- 更新调用QoS
local function update_qos_rules()
    local ret=false
    if not check_ifb_up() then return false end

    -- 读取配置文件（TODO: 这里需要添加一个触发开关，只有通过命令行触发的配置改变才能激发重读qos config）
    if not read_qos_config() then
        -- logger(3,'config no changed.')
        return false
    end

    if qdisc[cur_qdisc].changed() or old_qdisc ~= cur_qdisc then
        ret = qdisc[cur_qdisc].apply(old_qdisc,cfg.bands,cfg.DEVS,false)
        cfg.qdisc.old = cfg.qdisc.cur
    end

    return ret
end

-- 为FIX-版本更新简化QoS
local function update_fix_qos_rules()

    -- 读取配置文件
    if not read_qos_config() then
        return false
    end

    if cfg.enabled.flag == '0' then    -- clean rule & exit if qos off
        system_exit()
    end

    if qdisc[cur_qdisc] then
        if qdisc[cur_qdisc].apply then
            logger(3,'-------------apply '..cur_qdisc)
            return qdisc[cur_qdisc].apply(nil,cfg.bands,cfg.DEVS,true,true)
        end
    else
        logger(3, 'service-mode-qdisc not exist.')
    end
    return false
end


-- 读取uptime计数
local function get_uptime()
    local pp=io.open('/proc/uptime')
    local n=pp:read('*n')
    pp:close()
    return math.ceil(n)
end

-- 主循环
local function main_loop()

    util.exec('rm -rf ' .. cfg.server.path)
    assert(unsock:bind(cfg.server.path))
    assert(unsock:listen())
    unsock:settimeout(1)

    local now_time = get_uptime()
    local next_qos_time = now_time
    local delta
    local gc_timer=0

    -- tables for select event
    local set=newset()
    set:insert(unsock)    -- add 'server' into select events

    while true do

        now_time = get_uptime()       -- 读取当前的uptime ticks
        if now_time >= next_qos_time then
            if update_qos_rules() then
                gc_timer = gc_timer + 1
                if gc_timer >= 180 then
                    gc_timer = 0
                    local tmp_cnt = collectgarbage('count')

                    logger(3,p_sysinfo())
                end

                -- 更新tc的counters,便于直接调用返回
                update_counters(cfg.DEVS)
            end

            next_qos_time = now_time + cfg.check_interval      -- 更新下一次update QOS检测时间
        end

        delta = next_qos_time - now_time
        if delta > cfg.check_interval then
            logger(3, "Warning!!! plz check Update QoS delta = " .. delta .. ", it's too long!!!!")
            delta = cfg.check_interval
        end

        local readable, _, error = socket.select(set, nil , delta)
        for _,v in ipairs(readable) do

            if v == unsock then
                -- logger(3, 'new client come in ...')

                local clt=v:accept()
                if clt then
                    clt:settimeout(1)
                    set:insert(clt)
                else
                    logger(3, 'accept client error.')
                end
            else
                local data,error = v:receive()

                if error then
                    v:close()
                    -- logger(3, 'client is disconnected.')
                    set:remove(v)
                else
                    local args=string.split(data,' ')
                    local res,execflag='',''
                    if not args[1] then
                        res={status=3,data='cmd is NULL.'}
                    elseif args[1] == 'die' then
                        v:send(json.encode({status=0}) .. "\n")
                        v:close()
                        logger(3,"======== COMMAND `qos die` ============")
                        system_exit()       ---===OVER NOW===---

                    else
                        -- 命令行的处理
                        res,execflag = process_cmd(unpack(args))
                        if execflag then    -- 触发立即执行更新qos操作
                            next_qos_time = 0
                        end
                    end

                    v:send(json.encode(res) .. '\n')
                    v:close()
                    set:remove(v)
                end
            end
        end
    end
end

function main_once()

    -- FIX 模式强制service模式
    cur_qdisc='service'

    local res={result=0,data='ok'}
    cfg.DEVS={
            UP={dev=read_interfaces("wan"),id='2',},
            DOWN={dev="ifb0",id='1',},
        }
    if not QOS_CMD or not QOS_CMD[1] then
        update_fix_qos_rules()
    else
        -- 命令行的处理
        read_qos_config()
        res,execflag = process_cmd(unpack(QOS_CMD))

        if execflag then    -- 触发立即执行更新qos操作
            update_fix_qos_rules()
        end
    end

    if g_debug then pr(res) end

end


--[[main]]-------------------
local function main()

    if system_init() then
        local s,e
        if QOS_VER == 'FIX' then
            -- logger(3, 'apply rule as FIX mode.')
            s, e = pcall(function() main_once() end)
        else
            -- logger(3, 'apply rule as non-FIX mode.')
            s, e = pcall(function() main_loop() end)
        end
        if not s
        then
            logger(3,e)
            cleanup_system()
        end
    else
        logger(3, 'system initial failed. exit.')
    end
end

main()

--[[main end]]-------------------