#!/usr/bin/lua

package.path = package.path..";/home/paul/git/micodus_server/html/?.lua"

local const = require("const")
local json = require("json")
local server = require("nginx.websocket.server")
local sqlite = require("lsqlite3")

--ngx.shared.geo:set("last_time","")
local db = sqlite.open(const.dbfile, sqlite.OPEN_READONLY)

function getdata()
  local res, vm = db:nrows(const.query)
  local data = {}
  for row in res, vm do
    data = {
      ["time"] = row.time,
      ["latitude"] = row.latitude,
      ["longitude"] = row.longitude,
      ["height"] = row.height,
      ["speed"] = row.speed,
      ["direction"] = row.direction,
      ["serial"] = row.serial,
    }
  end
  return data
end

function geows()
  local locstr = nil
  local wb, err = server:new {
    timeout = 5000,
    max_payload_len = 65535
  }
  if not wb then
    ngx.log(ngx.ERR, "failed to new websocket: ", err)
    return ngx.exit(444)
  end
  local last_time = nil

  while true do
    local data = getdata()
    if data.time ~= last_time then
      local locstr = json.encode(data)
      local bytes, err = wb:send_text(locstr)
      if not bytes then
        ngx.log(ngx.ERR, "failed to send text: ", err)
        return ngx.exit(444)
      end
      last_time = data.time
    end
    ngx.sleep(0.5)
  end
  wb:send_close()
end

geows()