local syslog=require("syslog")
local math=require("math")
local cjson=require("cjson") 


-------------------------[全局参数定义]-------------------------

data_report_interv=60       --一次平均数 1小时,也是上报时间 default:3600
compare_interv=24           --一次比对计算 24小时
history_data=2*30           --存储 2 月历史记录
-------------------------[输入设备名称以及标识符]-------------------------
device_a="210163000001"
device_b="444222112"
value_name_a="doValue"
value_name_b="weiyi"

-------------------------[输出标识符]-------------------------
identifier="Event"
event_value_name="level"

-------------------------[事件参数]-------------------------
warning_level_1=60
warning_level_2=70
warning_level_3=80

-------------------------[系统变量]------------------------
raw_data_cache_size=100  --缓存大小
fit_data_cache_size=10  --滤波器缓存大小

syslog.openlog("chenjiang syslog", syslog.LOG_PERROR + syslog.LOG_ODELAY, "LOG_USER")


function write_cache_to_file(path,ojb)
    local file=io.open(path, 'w+')
    file:seek('set')
    file:write(cjson.encode(ojb))
    file:flush()
    file:close()
end

function read_cache_from_file(path)
    local file=io.open(path, 'a+')
    local ojb={}
    file:seek('set')
    ojb = file:read()
    file:close()
    if(ojb == nil) then return nil end
    return cjson.decode(ojb)
end

function process_event(raw_data,avg_cache)
    local fit_data={}
    local sum=0.0
    --复制到fit表,复制最近几条数据
    for i=#raw_data.list,#raw_data.list-fit_data_cache_size,-1 do 
        if raw_data.list[i] then table.insert( fit_data, raw_data.list[i]) end
    end
    local json_str=cjson.encode(fit_data)

    --排序去头去尾
    table.sort( fit_data )
    table.remove( fit_data,#fit_data)
    table.remove( fit_data,1)

    local json_str=cjson.encode(fit_data)
    print("fit_data",json_str, #json_str)
    for i=1,#fit_data,1 do
        sum = sum + fit_data[i] 
    end
    local avg_value = sum/#fit_data
    local level=0
    if avg_value >= warning_level_3 or avg_value <= 0-warning_level_3  then level =3 
    elseif avg_value >= warning_level_2 or avg_value <= 0-warning_level_2  then level =2 
    elseif avg_value >= warning_level_1  or avg_value <= 0-warning_level_1 then level =1 
    else
    end

    if (level ~= avg_cache.last_level ) then 
        local new_data={}
        new_data['timestamp']=os.time()
        new_data['identifier']=identifier
        new_data[event_value_name]=level
        avg_cache.last_level = level;
        write_cache_to_file("/tmp/chenjiang_avg_24h.dat",avg_cache)
        local json_str=cjson.encode(new_data)
        syslog.syslog("LOG_WARNING", json_str .. #json_str)
        return 0,json_str,#json_str
    end
    return -1
end

function process_data(raw_data)
    local curr_timestamp=os.time()
    local json_str=cjson.encode(raw_data)
    local cache = read_cache_from_file("/tmp/chenjiang_avg_24h.dat")
    if not cache then     cache={}     cache.list={}  cache.timestamp_1h=0 cache.last_level=0 syslog.syslog("LOG_WARNING","table init") end
    err_code,out_str,out_len = process_event(raw_data,cache)  --判断事件
    if(err_code)==0 then return err_code,out_str,out_len end
    if  curr_timestamp  >= (cache.timestamp_1h + data_report_interv) then       --数据平滑后上报
        cache.timestamp_1h = curr_timestamp
        local sum=0.0
        for i=1,#raw_data.list,1 do
            sum = sum + raw_data.list[i]
        end
        cache.avg_value = sum/#raw_data.list

        if #cache.list > compare_interv then table.remove( cache.list, 1 ) end
        table.insert(cache.list, cache.avg_value ) 

        write_cache_to_file("/tmp/chenjiang_avg_24h.dat",cache)
        local json_str=cjson.encode(cache)
        print("avg_data_24h",json_str, #json_str)

        hist = read_cache_from_file("/app/chenjiang_history.dat")
        local date = os.date("*t", os.time());
        if not hist then     
            hist={} 
            hist.list={} 
            hist.timestamp=0 
            hist.date = os.date("*t", os.time());
            hist.before_day_value=cache.list[#cache.list]
            hist.today_value=cache.list[#cache.list]
            syslog.syslog("LOG_WARNING","table init")  
        end
        if date["data"] ~= hist.date["data"] and date["hour"] == 8 then   -- 8 地方时区
            hist.timestamp = curr_timestamp 
            hist.date = os.date("*t", os.time());
            hist.before_day_value =  hist.today_value   --DATA t-1
            hist.today_value = cache.list[#cache.list]
            hist.value_diff = math.abs(hist.today_value - hist.before_day_value)
            if #hist.list > history_data then table.remove( hist.list, 1 ) end
            table.insert(hist.list, hist.value_diff ) 
            local sum=0.0
            for i=1,#hist.list,1 do
                sum = sum + hist.list[i]
            end
            hist.value_diff_add = sum
            write_cache_to_file("/app/chenjiang_history.dat",hist)
        end
    
        local new_data={}
        new_data['timestamp']=os.time()
        new_data['avg_value']=cache.avg_value
        new_data['avg_value_24']=hist.today_value
        new_data['diff_data_24']=hist.value_diff
        new_data['add_value_24_2M']=hist.value_diff_add
        local json_str=cjson.encode(new_data)
        syslog.syslog("LOG_WARNING", json_str .. #json_str)
        return 0,json_str,#json_str
    end
    return -1,nil,0 --中间计算结果不返回

end

function udef_process(obj)
    local err_code=0
    local cache = read_cache_from_file("/tmp/chenjiang_raw.dat")
    if not cache then     cache={}     cache.list={}     end
    if #cache.list > raw_data_cache_size then table.remove( cache.list, 1 ) end
    table.insert(cache.list, obj.raw_diff ) 
    write_cache_to_file("/tmp/chenjiang_raw.dat",cache)
    return process_data(cache)
end
        
function parser_input(obj)
    local source_a, source_b
    for i,v in pairs(obj["datas"]) do
        if(v["sn"] == device_a) then
            tag = v["tags"]
            if tag then
                source_a = tag[value_name_a]
            end
        elseif(v["sn"] == device_b) then
            tag = v["tags"]
            if tag then
                source_b = tag[value_name_b]
            end
        end
    end
    return source_a,source_b
end

function protocol_decode(input_str, len)
  --出参格式化--
  local obj = cjson.decode(input_str)
  --获取输入变量--
local source_a, source_b = parser_input(obj)
if source_a == nil or source_b == nil then
    print(source_a,source_b)
    syslog.syslog("LOG_WARNING","input args less than 2,one or more args missed")
    return -1,nil,0
end
syslog.syslog("LOG_WARNING",string.format( "source data[%f,%f]",source_a,source_b))

local json_obj={}
json_obj.raw_diff = source_a - source_b
err_code,out_str,out_len=udef_process(json_obj)
  --用户自定义数据处理
--   status,err_code = pcall(udef_process, json_obj)
--   if not status or not err_code then
--       if not status then
--         syslog.syslog("LOG_WARNING","err:FATAL")
--       end
--       return -3,nil,0
--   end
-- syslog.syslog("LOG_WARNING", string.format( "return code:%d",err_code))
return err_code,out_str,out_len
end
-- protocol_decode('{"datas":[{"sn":"210163000001","time":1574933970,"state":0,"quality":0,"identifier":"post","tags":{"doValue":10}},{"sn":"444222112","time":1574933967,"state":0,"quality":0,"identifier":"post","tags":{"weiyi":100}}]}', 0)


syslog.closelog()