-- KEYS[1]: the job data hash
-- KEYS[2]: the active job list
-- KEYS[3]: the signal list

-- ARGV[1]: the job ID
-- ARGV[2]: the serialized job data

-- Returns: 1 if the job was newly enqueued, 0 if it already exists

-- Set job data in hash
local set = redis.call("hsetnx", KEYS[1], ARGV[1], ARGV[2])

if set == 1 then
  -- If it was set, push the job on to the active list
  redis.call("rpush", KEYS[2], ARGV[1])

  -- Signal that there are jobs in the queue
  redis.call("del", KEYS[3])
  redis.call("lpush", KEYS[3], 1)
end

return set