// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
// vim: ts=8 sw=2 smarttab

#include "tools/rbd/ArgumentTypes.h"
#include "tools/rbd/Shell.h"
#include "tools/rbd/Utils.h"
#include "include/stringify.h"
#include "common/SubProcess.h"
#include <iostream>
#include <boost/algorithm/string/predicate.hpp>
#include <boost/scope_exit.hpp>
#include <boost/program_options.hpp>

namespace rbd {
namespace action {
namespace nbd {

namespace at = argument_types;
namespace po = boost::program_options;

static int call_nbd_cmd(const po::variables_map &vm,
                        const std::vector<const char*> &args)
{
  char exe_path[PATH_MAX];
  ssize_t exe_path_bytes = readlink("/proc/self/exe", exe_path,
				    sizeof(exe_path) - 1);
  if (exe_path_bytes < 0) {
    strcpy(exe_path, "rbd-nbd");
  } else {
    if (snprintf(exe_path + exe_path_bytes,
                 sizeof(exe_path) - exe_path_bytes,
                 "-nbd") < 0) {
      return -EOVERFLOW;
    }
  }

  SubProcess process(exe_path, SubProcess::KEEP, SubProcess::KEEP, SubProcess::KEEP);

  if (vm.count("conf")) {
    process.add_cmd_arg("--conf");
    process.add_cmd_arg(vm["conf"].as<std::string>().c_str());
  }
  if (vm.count("cluster")) {
    process.add_cmd_arg("--cluster");
    process.add_cmd_arg(vm["cluster"].as<std::string>().c_str());
  }
  if (vm.count("id")) {
    process.add_cmd_arg("--id");
    process.add_cmd_arg(vm["id"].as<std::string>().c_str());
  }
  if (vm.count("name")) {
    process.add_cmd_arg("--name");
    process.add_cmd_arg(vm["name"].as<std::string>().c_str());
  }
  if (vm.count("mon_host")) {
    process.add_cmd_arg("--mon_host");
    process.add_cmd_arg(vm["mon_host"].as<std::string>().c_str());
  }
  if (vm.count("keyfile")) {
    process.add_cmd_arg("--keyfile");
    process.add_cmd_arg(vm["keyfile"].as<std::string>().c_str());
  }
  if (vm.count("keyring")) {
    process.add_cmd_arg("--keyring");
    process.add_cmd_arg(vm["keyring"].as<std::string>().c_str());
  }

  for (std::vector<const char*>::const_iterator p = args.begin();
       p != args.end(); ++p)
    process.add_cmd_arg(*p);

  if (process.spawn()) {
    std::cerr << "rbd: failed to run rbd-nbd: " << process.err() << std::endl;
    return -EINVAL;
  } else if (process.join()) {
    std::cerr << "rbd: rbd-nbd failed with error: " << process.err() << std::endl;
    return -EINVAL;
  }

  return 0;
}

void get_show_arguments(po::options_description *positional,
                        po::options_description *options)
{ }

int execute_show(const po::variables_map &vm)
{
  std::vector<const char*> args;

  args.push_back("list-mapped");

  return call_nbd_cmd(vm, args);
}

void get_map_arguments(po::options_description *positional,
                       po::options_description *options)
{
  at::add_image_or_snap_spec_options(positional, options,
                                     at::ARGUMENT_MODIFIER_NONE);
  options->add_options()
    ("read-only", po::bool_switch(), "map read-only")
    ("exclusive", po::bool_switch(), "forbid writes by other clients")
    ("device", po::value<std::string>(), "specify nbd device")
    ("nbds_max", po::value<std::string>(), "override module param nbds_max")
    ("max_part", po::value<std::string>(), "override module param max_part");
}

int execute_map(const po::variables_map &vm)
{
  size_t arg_index = 0;
  std::string pool_name;
  std::string image_name;
  std::string snap_name;
  int r = utils::get_pool_image_snapshot_names(
    vm, at::ARGUMENT_MODIFIER_NONE, &arg_index, &pool_name, &image_name,
    &snap_name, utils::SNAPSHOT_PRESENCE_PERMITTED,
    utils::SPEC_VALIDATION_NONE);
  if (r < 0) {
    return r;
  }

  std::vector<const char*> args;

  args.push_back("map");
  std::string img;
  img.append(pool_name);
  img.append("/");
  img.append(image_name);
  if (!snap_name.empty()) {
    img.append("@");
    img.append(snap_name);
  }
  args.push_back(img.c_str());

  if (vm["read-only"].as<bool>())
    args.push_back("--read-only");

  if (vm["exclusive"].as<bool>())
    args.push_back("--exclusive");

  if (vm.count("device")) {
    args.push_back("--device");
    args.push_back(vm["device"].as<std::string>().c_str());
  }
  if (vm.count("nbds_max")) {
    args.push_back("--nbds_max");
    args.push_back(vm["nbds_max"].as<std::string>().c_str());
  }
  if (vm.count("max_part")) {
    args.push_back("--max_part");
    args.push_back(vm["max_part"].as<std::string>().c_str());
  }

  return call_nbd_cmd(vm, args);
}

void get_unmap_arguments(po::options_description *positional,
                   po::options_description *options)
{
  positional->add_options()
    ("device-spec", "specify nbd device");
}

int execute_unmap(const po::variables_map &vm)
{
  std::string device_name = utils::get_positional_argument(vm, 0);
  if (!boost::starts_with(device_name, "/dev/")) {
    device_name.clear();
  }

  if (device_name.empty()) {
    std::cerr << "rbd: nbd unmap requires device path" << std::endl;
    return -EINVAL;
  }

  std::vector<const char*> args;

  args.push_back("unmap");
  args.push_back(device_name.c_str());

  return call_nbd_cmd(vm, args);
}

Shell::SwitchArguments switched_arguments({"read-only"});

Shell::Action action_show(
  {"nbd", "list"}, {"nbd", "ls"}, "List the nbd devices already used.", "",
  &get_show_arguments, &execute_show);

Shell::Action action_map(
  {"nbd", "map"}, {}, "Map image to a nbd device.", "",
  &get_map_arguments, &execute_map);

Shell::Action action_unmap(
  {"nbd", "unmap"}, {}, "Unmap a nbd device.", "",
  &get_unmap_arguments, &execute_unmap);

} // namespace nbd
} // namespace action
} // namespace rbd