--
--  rhctl
--
--  Copyright (C) 2009-2014 Christian Pointner <equinox@helsinki.at>
--
--  This file is part of rhctl.
--
--  rhctl is free software: you can redistribute it and/or modify
--  it under the terms of the GNU General Public License as published by
--  the Free Software Foundation, either version 3 of the License, or
--  any later version.
--
--  rhctl is distributed in the hope that it will be useful,
--  but WITHOUT ANY WARRANTY; without even the implied warranty of
--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
--  GNU General Public License for more details.
--
--  You should have received a copy of the GNU General Public License
--  along with rhctl. If not, see <http://www.gnu.org/licenses/>.
--

package.path = package.path .. ';/usr/share/rhctl/?.lua'

socket = require("socket")
utils = require("utils")

old_state = {}
current_state = {}

function state_changed()
   for k,v in pairs(old_state) do
       if v ~= current_state[k] then
           return true
       end
   end
   for k,v in pairs(current_state) do
       if old_state[k] == nil then
           return true
       end
   end
   return false
end

function process_cmd(message)
   local exps = { hs = "^Health: (%a+)$", mc = "^Master: (%a+)$", sc = "^Standby: (%a+)$", hbm = "^Hearbeat Master: (%a+, %a+)$", hbs = "^Hearbeat Standby: (%a+, %a+)$" }
   for key, exp in pairs(exps) do
      local state = string.match(message, exp)
      if(state) then
         if(key == 'hs') then
            current_state = {}
         end
         current_state[key] = state
      end
   end

   if(current_state['hbs'] ~= nil) then
      if(state_changed()) then
         body = "RHCTL Health Output:\n\n"
         body = body .. "Health: " .. current_state['hs'] .. "\n"
         body = body .. "Master: " .. current_state['mc'] .. "\n"
         body = body .. "Standby: " .. current_state['sc'] .. "\n"
         body = body .. "Master Hearbeat: " .. current_state['hbm'] .. "\n"
         body = body .. "Standby Hearbeat: " .. current_state['hbs'] .. "\n"
         utils.send_mail("logs@helsinki.at", "[RHCTL] health: " .. current_state['hs'], body)
         old_state = current_state
      end
   end

   return 0
end

function main_loop(opt)
   log.printf(log.NOTICE, "main_loop started")
   local sig = signal.init()
   local cmdfd = cmd.init()

   cmd.send_string("listen health");
   cmd.send_string("health");

   local return_value = 0
   while return_value == 0 do
      local readable, _, err = socket.select({ sig , cmdfd }, nil)
      if(err) then
         log.printf(log.ERROR, "select returned with error: %s", err)
         return_value = -1
      else
         for _, input in ipairs(readable) do
            if(input == sig) then
               return_value = signal.handle()
               if(return_value == 1) then break end
            else
               if(input == cmdfd) then
                  return_value = cmd.recv_data(process_cmd)
                  if(return_value ~= 0) then break end
               else
                  log.printf(log.ERROR, "select returned invalid handle??")
                  return_value = -1
                  break;
               end
            end
         end
      end
   end

   signal.stop()
   return return_value
end