On-call handoff

# title: On-call handoff
# category: Vibescript Showcase
# difficulty: Showcase
# summary: Build an on-call handoff from the coverage level and shift length.
# description: An enum names the coverage level. Durations set the shift and reminder times.
# tags: operations, durations, enums, on-call
# vibe: 0.2

enum CoverageLevel
  Primary
  Secondary
  Commander
end

def shift_length(level: CoverageLevel) -> duration
  if level == CoverageLevel::Primary
    8.hours
  elsif level == CoverageLevel::Secondary
    12.hours
  else
    24.hours
  end
end

def handoff_packet(service: string, level: CoverageLevel, started_at: time) -> hash
  length = shift_length(level)
  ends_at = length.after(started_at)

  {
    service: service,
    level: level.name,
    starts_at: started_at.format("2006-01-02T15:04:05Z"),
    ends_at: ends_at.format("2006-01-02T15:04:05Z"),
    reminder_at: 30.minutes.ago(ends_at).format("2006-01-02T15:04:05Z"),
    summary: "{{service}} {{level}} handoff".template({ service: service, level: level.name })
  }
end

def run
  started_at = Time.at(1701100000)

  {
    primary: handoff_packet("payments-api", CoverageLevel::Primary, started_at),
    commander: handoff_packet("payments-api", CoverageLevel::Commander, started_at)
  }
end