require 'speed_gun'

class SpeedGun::Event
  def self.from_hash(id, hash)
    event = new(
      hash['name'],
      hash['payload'],
      Time.at(hash['started_at']),
      hash['finished_at'] ? Time.at(hash['finished_at']) : nil
    )
    event.instance_variable_set(:@id, id)

    event
  end

  # @return [String] event ID
  attr_reader :id

  # @return [String] event name
  attr_reader :name

  # @return [Hashie::Mash] payload
  attr_reader :payload

  # @return [Time] start time
  attr_reader :started_at

  # @return [Time, nil] finish time
  attr_reader :finished_at

  # @param name [String] event name
  # @param payload [Hash] payload
  # @param started_at [Time] start time
  # @param finished_at [Time, nil] finish time
  # @return [SpeedGun::Event] instance of SpeedGun::Event
  def initialize(name, payload = {}, started_at = Time.now, finished_at = nil)
    @id = SecureRandom.uuid
    @name = name
    @payload = Hashie::Mash.new(payload)
    @started_at = started_at
    @finished_at = finished_at
  end

  # Finish event
  #
  # @return [Time] finish time
  def finish!
    @finished_at = Time.now
  end

  # @return [true, false] true if the event is finished
  def finished?
    !@finished_at.nil?
  end

  # Time duration of the event
  #
  # @return [Float] a duration of the event
  def duration
    finished? ? finished_at.to_f - started_at.to_f : -1
  end

  def to_hash
    {
      'name' => name,
      'payload' => payload,
      'started_at' => started_at.to_f,
      'finished_at' => finished? ? finished_at.to_f : nil,
      'duration' => duration
    }
  end
end