# frozen_string_literal: true
#
# Copyright 2021- MahithaB
#
# 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.

require 'concurrent'
require 'rest-client'
require 'fluent/plugin/input'
require_relative 'metrics_parser'
require_relative 'metrics_helper'

module Fluent
  module Plugin
    class JfrogMetricsInput < Fluent::Plugin::Input
      Fluent::Plugin.register_input('jfrog_metrics', self)
      helpers :timer
      # `config_param` defines a parameter.
      # You can refer to a parameter like an instance variable e.g. @port.
      # `:default` means that the parameter is optional.
      config_param :tag, :string, default: ''
      config_param :jpd_url, :string, default: ''
      config_param :username, :string, default: ''
      config_param :apikey, :string, default: ''
      config_param :interval, :time, default: 10
      config_param :metric_prefix, :string, default: ''

      # `configure` is called before `start`.
      # 'conf' is a `Hash` that includes the configuration parameters.
      # If the configuration is invalid, raise `Fluent::ConfigError`.
      def configure(conf)
        super
        raise Fluent::ConfigError, 'Must define the tag for metrics data.' if @tag == ''

        raise Fluent::ConfigError, 'Must define the jpd_url to scrape metrics' if @jpd_url == ''

        raise Fluent::ConfigError, 'Must define the username for authentication' if @username == ''

        raise Fluent::ConfigError, 'Must define the apikey to use for authentication.' if @apikey == ''

        raise Fluent::ConfigError, 'Must define the interval to use for gathering the metrics.' if @interval == ''

        raise Fluent::ConfigError, 'Must define the metric_prefix to use for getting the metrics.' if @metric_prefix == ''
      end

      # `start` is called when starting and after `configure` is successfully completed.
      def start
        super
        @running = true
        @thread = Thread.new(&method(:run))
      end

      def shutdown
        @running = false
        @thread.join
        super
      end

      def run
        puts('Preparing metrics collection, creating timer task')
        timer_task = Concurrent::TimerTask.new(execution_interval: @interval, timeout_interval: 30, run_now: true) do
          puts('Timer task execution')
          do_execute
        end
        timer_task.execute
      end

      def do_execute
        puts('Executing metrics collection')
        metrics_helper = MetricsHelper.new(@metric_prefix, @jpd_url, @username, @apikey)
        platform_metrics = metrics_helper.get_metrics
        parser = MetricsParser.new(@metric_prefix, router, @tag)
        parser.emit_parsed_metrics(platform_metrics)
      end
    end
  end
end