Reminder schedule

# title: Reminder schedule
# category: Vibescript Showcase
# difficulty: Showcase
# summary: Generate reminder jobs with enum channels, Duration lead times, and template-based subjects.
# description: This example shows how Vibescript can express notification scheduling with clean typed helpers and deterministic output.
# tags: notifications, durations, enums, templates
# featured: true
# feature_rank: 5
# vibe: 0.2

enum ReminderChannel
  Email
  Sms
  Push
end

def lead_time(channel: ReminderChannel) -> duration
  if channel == ReminderChannel::Email
    Duration.build(hours: 48)
  elsif channel == ReminderChannel::Sms
    Duration.parse("PT6H")
  else
    Duration.parse("PT30M")
  end
end

def reminder_job(invoice_id: string, due_at: time, channel: ReminderChannel) -> hash
  delta = lead_time(channel)
  send_at = delta.ago(due_at)

  {
    invoice_id: invoice_id,
    channel: channel.name,
    lead_time: delta.iso8601,
    send_at: send_at.format("2006-01-02T15:04:05Z"),
    subject: "Invoice {{invoice}} is due soon".template({ invoice: invoice_id })
  }
end

def run
  due_at = Time.at(1700600000)
  {
    email: reminder_job("inv_2026_0042", due_at, ReminderChannel::Email),
    sms: reminder_job("inv_2026_0042", due_at, ReminderChannel::Sms),
    push: reminder_job("inv_2026_0042", due_at, ReminderChannel::Push)
  }
end