module Gush
  class Job

    attr_accessor :workflow_id, :incoming, :outgoing,
      :finished_at, :failed_at, :started_at, :enqueued_at

    attr_reader :name

    def initialize(workflow, opts = {})
      @workflow = workflow
      options = opts.dup
      assign_variables(options)
    end

    def as_json
      {
        name: @name,
        klass: self.class.to_s,
        finished: finished?,
        enqueued: enqueued?,
        failed: failed?,
        incoming: @incoming,
        outgoing: @outgoing,
        finished_at: finished_at,
        enqueued_at: enqueued_at,
        started_at: started_at,
        failed_at: failed_at,
        running: running?
      }
    end

    def to_json(options = {})
      Gush::JSON.encode(as_json)
    end

    def self.from_hash(flow, hash)
      hash[:klass].constantize.new(flow, hash)
    end

    def work
    end

    def start!
      @started_at = current_timestamp
    end

    def enqueue!
      @enqueued_at = current_timestamp
      @started_at = nil
      @finished_at = nil
      @failed_at = nil
    end

    def finish!
      @finished_at = current_timestamp
    end

    def fail!
      @finished_at = current_timestamp
      @failed_at = current_timestamp
    end

    def enqueued?
      !!enqueued_at
    end

    def finished?
      !!finished_at
    end

    def failed?
      !!failed_at
    end

    def succeeded?
      finished? && !failed?
    end

    def running?
      !!started_at && !finished?
    end

    def ready_to_start?
      !running? && !enqueued? && !finished? && !failed?
    end

    def has_no_dependencies?
      incoming.empty?
    end

    private

    def current_timestamp
      Time.now.to_i
    end

    def assign_variables(options)
      @name        = options[:name]
      @incoming    = options[:incoming] || []
      @outgoing    = options[:outgoing] || []
      @failed_at   = options[:failed_at]
      @finished_at = options[:finished_at]
      @started_at  = options[:started_at]
      @enqueued_at = options[:enqueued_at]
    end
  end
end