Coffee alarm at the office.

coffee_alarm.jl

using Dates: DateTime, issaturday, issunday, now, tonext, Hour, hour, Minute

isweekend(dt::DateTime) = issaturday(dt) || issunday(dt)

# Step from now on by 1 hour lapses until the next coffee time is found.
next_coffee_t = tonext(floor(now(),Hour), step=Hour(1)) do dt
   !isweekend(dt)  && # We do not work at the office on weekends.
   (hour(dt) == 13 || # After lunch, or
    hour(dt) == 17)   # in the evening.
end

# Exactly how much time is left [milliseconds].
t_left = next_coffee_t - now()

# Notification:
if t_left < Minute(10)
   println("Let's prepare some ☕!")
else
   hours_left = round(t_left, Hour)
   mins_left  = round(t_left, Minute) - Minute(hours_left)
   if mins_left < Minute(0)
      hours_left -= Hour(1)
      mins_left  += Minute(60)
   end
   println(hours_left, " ", mins_left , " left for ☕.")
end