module Ops
  class HealthMonitorJob
    include Sidekiq::Job

    sidekiq_options retry: 1, queue: "default"

    INTERVAL_SECS = ENV.fetch("OPS_HEALTH_INTERVAL_SECS", "180").to_i
    REDIS_CHAIN_KEY = "ops:health_monitor:chain"
    HEARTBEAT_KEY = "ops:health_monitor:last_run"

    def self.ensure_chain
      return unless redis

      return if redis.get(REDIS_CHAIN_KEY)

      redis.set(REDIS_CHAIN_KEY, "1", ex: INTERVAL_SECS * 2)
      perform_in(INTERVAL_SECS)
    end

    def self.redis
      @redis ||= Redis.new(url: ENV.fetch("REDIS_URL", "redis://localhost:6379/0"))
    rescue Redis::CannotConnectError
      nil
    end

    def perform
      self.class.redis&.set(HEARTBEAT_KEY, Time.current.to_i, ex: INTERVAL_SECS * 3)
      Ops::HealthChecks.new.call
    ensure
      self.class.perform_in(INTERVAL_SECS)
    end
  end
end