// -*- 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 "common/errno.h"
#include "common/Formatter.h"
#include "common/TextTable.h"
#include <iostream>
#include <boost/program_options.hpp>

namespace rbd {
namespace action {
namespace lock {

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

namespace {

void add_id_option(po::options_description *positional) {
  positional->add_options()
    ("lock-id", "unique lock id");
}

int get_id(const po::variables_map &vm, std::string *id) {
  *id = utils::get_positional_argument(vm, 1);
  if (id->empty()) {
    std::cerr << "rbd: lock id was not specified" << std::endl;
    return -EINVAL;
  }
  return 0;
}

} // anonymous namespace

static int do_lock_list(librbd::Image& image, Formatter *f)
{
  std::list<librbd::locker_t> lockers;
  bool exclusive;
  std::string tag;
  TextTable tbl;
  int r;

  r = image.list_lockers(&lockers, &exclusive, &tag);
  if (r < 0)
    return r;

  if (f) {
    f->open_object_section("locks");
  } else {
    tbl.define_column("Locker", TextTable::LEFT, TextTable::LEFT);
    tbl.define_column("ID", TextTable::LEFT, TextTable::LEFT);
    tbl.define_column("Address", TextTable::LEFT, TextTable::LEFT);
  }

  if (lockers.size()) {
    bool one = (lockers.size() == 1);

    if (!f) {
      std::cout << "There " << (one ? "is " : "are ") << lockers.size()
           << (exclusive ? " exclusive" : " shared")
           << " lock" << (one ? "" : "s") << " on this image.\n";
      if (!exclusive)
        std::cout << "Lock tag: " << tag << "\n";
    }

    for (std::list<librbd::locker_t>::const_iterator it = lockers.begin();
         it != lockers.end(); ++it) {
      if (f) {
        f->open_object_section(it->cookie.c_str());
        f->dump_string("locker", it->client);
        f->dump_string("address", it->address);
        f->close_section();
      } else {
        tbl << it->client << it->cookie << it->address << TextTable::endrow;
      }
    }
    if (!f)
      std::cout << tbl;
  }

  if (f) {
    f->close_section();
    f->flush(std::cout);
  }
  return 0;
}

static int do_lock_add(librbd::Image& image, const char *cookie,
                       const char *tag)
{
  if (tag)
    return image.lock_shared(cookie, tag);
  else
    return image.lock_exclusive(cookie);
}

static int do_lock_remove(librbd::Image& image, const char *client,
                          const char *cookie)
{
  return image.break_lock(client, cookie);
}

void get_list_arguments(po::options_description *positional,
                        po::options_description *options) {
  at::add_image_spec_options(positional, options, at::ARGUMENT_MODIFIER_NONE);
  at::add_format_options(options);
}

int execute_list(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_NONE, utils::SPEC_VALIDATION_NONE);
  if (r < 0) {
    return r;
  }

  at::Format::Formatter formatter;
  r = utils::get_formatter(vm, &formatter);
  if (r < 0) {
    return r;
  }

  librados::Rados rados;
  librados::IoCtx io_ctx;
  librbd::Image image;
  r = utils::init_and_open_image(pool_name, image_name, "", "", true,
                                 &rados, &io_ctx, &image);
  if (r < 0) {
    return r;
  }

  r = do_lock_list(image, formatter.get());
  if (r < 0) {
    std::cerr << "rbd: listing locks failed: " << cpp_strerror(r) << std::endl;
    return r;
  }
  return 0;
}

void get_add_arguments(po::options_description *positional,
                       po::options_description *options) {
  at::add_image_spec_options(positional, options, at::ARGUMENT_MODIFIER_NONE);
  add_id_option(positional);
  options->add_options()
    ("shared", po::value<std::string>(), "shared lock tag");
}

int execute_add(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_NONE, utils::SPEC_VALIDATION_NONE);
  if (r < 0) {
    return r;
  }

  std::string lock_cookie;
  r = get_id(vm, &lock_cookie);
  if (r < 0) {
    return r;
  }

  std::string lock_tag;
  if (vm.count("shared")) {
    lock_tag = vm["shared"].as<std::string>();
  }

  librados::Rados rados;
  librados::IoCtx io_ctx;
  librbd::Image image;
  r = utils::init_and_open_image(pool_name, image_name, "", "", false,
                                 &rados, &io_ctx, &image);
  if (r < 0) {
    return r;
  }

  r = do_lock_add(image, lock_cookie.c_str(),
                  lock_tag.empty() ? nullptr : lock_tag.c_str());
  if (r < 0) {
    if (r == -EBUSY || r == -EEXIST) {
      if (!lock_tag.empty()) {
        std::cerr << "rbd: lock is already held by someone else"
                  << " with a different tag" << std::endl;
      } else {
        std::cerr << "rbd: lock is already held by someone else" << std::endl;
      }
    } else {
      std::cerr << "rbd: taking lock failed: " << cpp_strerror(r) << std::endl;
    }
    return r;
  }
  return 0;
}

void get_remove_arguments(po::options_description *positional,
                          po::options_description *options) {
  at::add_image_spec_options(positional, options, at::ARGUMENT_MODIFIER_NONE);
  add_id_option(positional);
  positional->add_options()
    ("locker", "locker client");
}

int execute_remove(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_NONE, utils::SPEC_VALIDATION_NONE);
  if (r < 0) {
    return r;
  }

  std::string lock_cookie;
  r = get_id(vm, &lock_cookie);
  if (r < 0) {
    return r;
  }

  std::string lock_client = utils::get_positional_argument(vm, 2);
  if (lock_client.empty()) {
    std::cerr << "rbd: locker was not specified" << std::endl;
    return -EINVAL;
  }

  librados::Rados rados;
  librados::IoCtx io_ctx;
  librbd::Image image;
  r = utils::init_and_open_image(pool_name, image_name, "", "", false,
                                 &rados, &io_ctx, &image);
  if (r < 0) {
    return r;
  }

  r = do_lock_remove(image, lock_client.c_str(), lock_cookie.c_str());
  if (r < 0) {
    std::cerr << "rbd: releasing lock failed: " << cpp_strerror(r) << std::endl;
    return r;
  }
  return 0;
}

Shell::Action action_list(
  {"lock", "list"}, {"lock", "ls"}, "Show locks held on an image.", "",
  &get_list_arguments, &execute_list);
Shell::Action action_add(
  {"lock", "add"}, {}, "Take a lock on an image.", "",
  &get_add_arguments, &execute_add);
Shell::Action action_remove(
  {"lock", "remove"}, {"lock", "rm"}, "Release a lock on an image.", "",
  &get_remove_arguments, &execute_remove);

} // namespace lock
} // namespace action
} // namespace rbd