/*  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
 * 
 *  Gearmand client and server library.
 *
 *  Copyright (C) 2011-2013 Data Differential, http://datadifferential.com/
 *  Copyright (C) 2008 Brian Aker, Eric Day
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions are
 *  met:
 *
 *      * Redistributions of source code must retain the above copyright
 *  notice, this list of conditions and the following disclaimer.
 *
 *      * Redistributions in binary form must reproduce the above
 *  copyright notice, this list of conditions and the following disclaimer
 *  in the documentation and/or other materials provided with the
 *  distribution.
 *
 *      * The names of its contributors may not be used to endorse or
 *  promote products derived from this software without specific prior
 *  written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 *
 */


/**
 * @file
 * @brief Blob slap worker utility
 */

#include "gear_config.h"
#include <benchmark/benchmark.h>
#include <boost/program_options.hpp>
#include <cerrno>
#include <cstdio>
#include <climits>
#include <iostream>
#include <vector>
#include "util/daemon.hpp"
#include "util/logfile.hpp"
#include "util/pidfile.hpp"
#include "util/signal.hpp"
#include "util/string.hpp"

using namespace datadifferential;

static void *worker_fn(gearman_job_st *job, void *context,
                       size_t *result_size, gearman_return_t *ret_ptr);

static gearman_return_t shutdown_fn(gearman_job_st*, void* /* context */)
{
  return GEARMAN_SHUTDOWN;
}

static gearman_return_t ping_fn(gearman_job_st*, void* /* context */)
{
  return GEARMAN_SUCCESS;
}


int main(int args, char *argv[])
{
  gearman_benchmark_st benchmark;
  bool opt_daemon;
  bool opt_chunk;
  bool opt_status;
  bool opt_unique;
  std::string pid_file;
  std::string log_file;
  int32_t timeout;
  uint32_t count= UINT_MAX;
  in_port_t port;
  std::string host;
  std::string identifier;
  std::vector<std::string> functions;
  std::string verbose_string;
  boost::program_options::options_description desc("Options");
  desc.add_options()
    ("help", "Options related to the program.")
    ("host,h", boost::program_options::value<std::string>(&host)->default_value("localhost"),"Connect to the host")
    ("identifier", boost::program_options::value<std::string>(&identifier)->default_value("blobslap_worker"), "Worker identifier")
    ("port,p", boost::program_options::value<in_port_t>(&port)->default_value(GEARMAN_DEFAULT_TCP_PORT), "Port number use for connection")
    ("count,c", boost::program_options::value<uint32_t>(&count)->default_value(0), "Number of jobs to run before exiting")
    ("timeout,u", boost::program_options::value<int32_t>(&timeout)->default_value(-1), "Timeout in milliseconds")
    ("chunk", boost::program_options::bool_switch(&opt_chunk)->default_value(false), "Send result back in data chunks")
    ("status,s", boost::program_options::bool_switch(&opt_status)->default_value(false), "Send status updates and sleep while running job")
    ("unique,u", boost::program_options::bool_switch(&opt_unique)->default_value(false), "When grabbing jobs, grab the uniqie id")
    ("daemon,d", boost::program_options::bool_switch(&opt_daemon)->default_value(false), "Daemonize")
    ("function,f", boost::program_options::value(&functions), "Function to use.")
    ("verbose,v", boost::program_options::value(&verbose_string)->default_value("v"), "Increase verbosity level by one.")
    ("pid-file", boost::program_options::value(&pid_file), "File to write process ID out to.")
    ("log-file", boost::program_options::value(&log_file), "Create a log file.")
            ;

  boost::program_options::variables_map vm;
  try
  {
    boost::program_options::store(boost::program_options::parse_command_line(args, argv, desc), vm);
    boost::program_options::notify(vm);
  }
  catch(std::exception &e)
  { 
    std::cout << e.what() << std::endl;
    return EXIT_FAILURE;
  }

  if (vm.count("help"))
  {
    std::cout << desc << std::endl;
    return EXIT_SUCCESS;
  }

  if (opt_daemon)
  {
    util::daemonize(false, true);
  }

  util::Pidfile _pid_file(pid_file);

  if (pid_file.empty() == false)
  {
    if (_pid_file.create() == false)
    {
      std::cerr << _pid_file.error_message().c_str();
      return EXIT_FAILURE;
    }
  }

  if (not log_file.empty())
  {
    FILE *file= fopen(log_file.c_str(), "w+");
    if (file == NULL)
    {
      std::cerr << "Unable to open:" << log_file << "(" << strerror(errno) << ")" << std::endl;
      return EXIT_FAILURE;
    }
    fclose(file);

    // We let the error from this happen later (if one was to occur)
    unlink(log_file.c_str());
  }

  gearman_worker_st *worker;
  if (not (worker= gearman_worker_create(NULL)))
  {
    std::cerr << "Failed to allocate worker" << std::endl;
    return EXIT_FAILURE;
  }

  if (getenv("GEARMAN_SERVERS") == NULL)
  {
    if (gearman_failed(gearman_worker_add_server(worker, host.c_str(), port)))
    {
      std::cerr << "Failed while adding server " << host << ":" << port << " :" << gearman_worker_error(worker) << std::endl;
      return EXIT_FAILURE;
    }
  }

  if (identifier.size())
  {
    gearman_worker_set_identifier(worker, identifier.c_str(), identifier.size());
  }


  benchmark.verbose= static_cast<uint8_t>(verbose_string.length());

  if (opt_daemon)
  {
    util::daemon_is_ready(benchmark.verbose == 0);
  }

  util::SignalThread signal(true);
  util::Logfile log(log_file);

  if (not log.open())
  {
    std::cerr << "Could not open logfile:" << log_file << std::endl;
    return EXIT_FAILURE;
  }

  if (not signal.setup())
  {
    log.log() << "Failed signal.setup()" << std::endl;
    return EXIT_FAILURE;
  }

  gearman_function_t shutdown_function= gearman_function_create(shutdown_fn);
  if (gearman_failed(gearman_worker_define_function(worker,
                                                    util_literal_param("shutdown"), 
                                                    shutdown_function,
                                                    0, 0)))
  {
    log.log() << "Failed to add shutdown function: " << gearman_worker_error(worker) << std::endl;
    return EXIT_FAILURE;
  }

  gearman_function_t ping_function= gearman_function_create(ping_fn);
  if (gearman_failed(gearman_worker_define_function(worker,
                                                    util_literal_param("blobslap_worker_ping"), 
                                                    ping_function,
                                                    0, 0)))
  {
    log.log() << "Failed to add blobslap_worker_ping function: " << gearman_worker_error(worker) << std::endl;
    return EXIT_FAILURE;
  }

  if (functions.empty() == false)
  {
    for (std::vector<std::string>::iterator iter= functions.begin(); iter != functions.end(); ++iter)
    {
      if (gearman_failed(gearman_worker_add_function(worker,
                                                     (*iter).c_str(), 0,
                                                     worker_fn, &benchmark)))
      {
        log.log() << "Failed to add default function: " << gearman_worker_error(worker) << std::endl;
        return EXIT_FAILURE;
      }
    }
  }
  else
  {
    if (gearman_failed(gearman_worker_add_function(worker,
                                                   GEARMAN_BENCHMARK_DEFAULT_FUNCTION, 0,
                                                   worker_fn, &benchmark)))
    {
      log.log() << "Failed to add default function: " << gearman_worker_error(worker) << std::endl;
      return EXIT_FAILURE;
    }
  }

  gearman_worker_set_timeout(worker, timeout);

  do
  {
    gearman_return_t rc= gearman_worker_work(worker);

    if (rc == GEARMAN_SHUTDOWN)
    {
      if (benchmark.verbose > 0)
      {
        log.log() << "shutdown" << std::endl;
      }
      break;
    }
    else if (gearman_failed(rc))
    {
      log.log() << "gearman_worker_work(): " << gearman_worker_error(worker) << std::endl;
      break;
    }

    count--;
  } while(count and (not signal.is_shutdown()));

  gearman_worker_free(worker);

  return EXIT_SUCCESS;
}

static void *worker_fn(gearman_job_st *job, void *context,
                       size_t *, gearman_return_t *ret_ptr)
{
  gearman_benchmark_st *benchmark= static_cast<gearman_benchmark_st *>(context);

  if (benchmark->verbose > 0)
  {
    benchmark_check_time(benchmark);
  }

  if (benchmark->verbose > 1)
  {
    std::cout << "Job=" << gearman_job_handle(job) << " (" << gearman_job_workload_size(job) << ")" << std::endl;
  }

  *ret_ptr= GEARMAN_SUCCESS;

  return NULL;
}