## This Source Code Form is subject to the terms of the Mozilla Public
## License, v. 2.0. If a copy of the MPL was not distributed with this
## file, You can obtain one at https://mozilla.org/MPL/2.0/.
##
## Copyright (c) 2007-2023 Broadcom. All Rights Reserved. The term “Broadcom” refers to Broadcom Inc. and/or its subsidiaries.  All rights reserved.

defmodule LogTailStreamCommandTest do
  use ExUnit.Case, async: false
  import TestHelper

  @command RabbitMQ.CLI.Diagnostics.Commands.LogTailStreamCommand

  setup_all do
    RabbitMQ.CLI.Core.Distribution.start()

    start_rabbitmq_app()

    ExUnit.configure(max_cases: 1)

    on_exit([], fn ->
      start_rabbitmq_app()
    end)

    :ok
  end

  setup context do
    {:ok,
     opts: %{
       node: get_rabbit_hostname(),
       timeout: context[:test_timeout] || 30000,
       duration: :infinity
     }}
  end

  test "merge_defaults: duration defaults to infinity" do
    assert @command.merge_defaults([], %{}) == {[], %{duration: :infinity}}
  end

  test "validate: treats positional arguments as a failure" do
    assert @command.validate(["extra-arg"], %{}) == {:validation_failure, :too_many_args}
  end

  test "validate: treats empty positional arguments and default switches as a success", context do
    assert @command.validate([], context[:opts]) == :ok
  end

  @tag test_timeout: 3000
  test "run: targeting an unreachable node throws a badrpc", context do
    assert match?(
             {:badrpc, _},
             @command.run([], Map.merge(context[:opts], %{node: :jake@thedog, timeout: 100}))
           )
  end

  test "run: streams messages for N seconds", context do
    ensure_log_file()
    time_before = System.system_time(:second)

    stream = @command.run([], Map.merge(context[:opts], %{duration: 15}))
    :rpc.call(get_rabbit_hostname(), :rabbit_log, :error, [to_charlist("Message")])
    :rpc.call(get_rabbit_hostname(), :rabbit_log, :error, [to_charlist("Message1")])
    :rpc.call(get_rabbit_hostname(), :rabbit_log, :error, [to_charlist("Message2")])
    :rpc.call(get_rabbit_hostname(), :rabbit_log, :error, [to_charlist("Message3")])

    # This may take a long time and fail with an ExUnit timeout
    data = Enum.join(stream)

    time_after = System.system_time(:second)

    assert String.match?(data, ~r/Message/)
    assert String.match?(data, ~r/Message1/)
    assert String.match?(data, ~r/Message2/)
    assert String.match?(data, ~r/Message3/)

    time_spent = time_after - time_before
    assert time_spent > 15
    # This my take longer then duration but not too long
    assert time_spent < 45
  end

  test "run: may return an error if there is no log", context do
    delete_log_files()
    {:error, :enoent} = @command.run([], Map.merge(context[:opts], %{duration: 5}))
  end

  def ensure_log_file() do
    [log | _] = :rpc.call(get_rabbit_hostname(), :rabbit, :log_locations, [])
    ensure_file(log, 100)
  end

  def ensure_file(log, 0) do
    flunk("timed out trying to ensure the log file #{log}")
  end

  def ensure_file(log, attempts) do
    case File.exists?(log) do
      true ->
        :ok

      false ->
        :rpc.call(get_rabbit_hostname(), :rabbit_log, :error, [to_charlist("Ping")])
        :timer.sleep(100)
        ensure_file(log, attempts - 1)
    end
  end

  def delete_log_files() do
    [_ | _] = logs = :rpc.call(get_rabbit_hostname(), :rabbit, :log_locations, [])

    Enum.map(logs, fn log ->
      File.rm(log)
    end)
  end
end
