/*
 * Copyright (C) 2023 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "cuttlefish/host/commands/cvd/cli/commands/restart.h"

#include <chrono>
#include <memory>
#include <string>
#include <vector>

#include "cuttlefish/flag_parser/flag.h"
#include "cuttlefish/flag_parser/gflags_compat.h"
#include "cuttlefish/host/commands/cvd/cli/command_request.h"
#include "cuttlefish/host/commands/cvd/cli/commands/command_handler.h"
#include "cuttlefish/host/commands/cvd/cli/selector/selector.h"
#include "cuttlefish/host/commands/cvd/cli/types.h"
#include "cuttlefish/host/commands/cvd/instances/instance_manager.h"
#include "cuttlefish/result/result.h"

namespace cuttlefish {
namespace {

constexpr char kSummaryHelpText[] = "Restart device";
constexpr char kDetailedHelpText[] =
    R"(restart: Reboots the virtual device

Flags:
    -boot_timeout (How many seconds to wait for the device to reboot.)
      type: int32 default: 1000
    -wait_for_launcher (How many seconds to wait for the launcher to respond to
      the status command. A value of zero means wait indefinitely.) type: int32
      default: 30
)";

constexpr char kRestartCmd[] = "restart";

struct RestartOptions {
  int wait_for_launcher_seconds = 30;
  int boot_timeout_seconds = 500;

  std::vector<Flag> Flags() {
    return {
        GflagsCompatFlag("wait_for_launcher", wait_for_launcher_seconds),
        GflagsCompatFlag("boot_timeout", boot_timeout_seconds),
    };
  }
};

}  // namespace

CvdDeviceRestartCommandHandler::CvdDeviceRestartCommandHandler(
    InstanceManager& instance_manager)
    : instance_manager_{instance_manager} {}

Result<void> CvdDeviceRestartCommandHandler::Handle(
    const CommandRequest& request) {
  RestartOptions options;
  std::vector<std::string> subcmd_args = request.SubcommandArguments();
  CF_EXPECT(ConsumeFlags(options.Flags(), subcmd_args,
                         {.fail_on_unexpected_argument = true}));

  auto [instance, group] =
      CF_EXPECT(selector::SelectInstance(instance_manager_, request),
                "Unable to select an instance");

  const auto& instances = group.Instances();
  if (!instances.empty() && instance.Id() == instances[0].Id()) {
    bool other_active = false;
    for (const auto& inst : instances) {
      if (inst.Id() != instance.Id() && inst.IsActive()) {
        other_active = true;
        break;
      }
    }
    CF_EXPECTF(
        !other_active,
        "Restarting the first instance (ID: {}) is not allowed "
        "while other instances are running. Restart the entire group instead.",
        instance.Id());
  }

  CF_EXPECT(
      instance.Restart(std::chrono::seconds(options.wait_for_launcher_seconds),
                       std::chrono::seconds(options.boot_timeout_seconds)));
  return {};
}

cvd_common::Args CvdDeviceRestartCommandHandler::CmdList() const {
  return {kRestartCmd};
}

std::string CvdDeviceRestartCommandHandler::SummaryHelp() const {
  return kSummaryHelpText;
}

bool CvdDeviceRestartCommandHandler::RequiresDeviceExists() const {
  return true;
}

Result<std::string> CvdDeviceRestartCommandHandler::DetailedHelp(
    const CommandRequest& request) {
  return kDetailedHelpText;
}

std::unique_ptr<CvdCommandHandler> NewCvdDeviceRestartCommandHandler(
    InstanceManager& instance_manager) {
  return std::unique_ptr<CvdCommandHandler>(
      new CvdDeviceRestartCommandHandler(instance_manager));
}

}  // namespace cuttlefish
