Wake up script for OSX

wakeup.sh

#!/bin/bash

wake_time="2018-03-04.02:30:00"
wake_time_epoch=$(date -j -f %Y-%m-%d.%H:%M:%S $wake_time +%s)

while [ 1 ]; do
    now_epoch=$(date +%s)
    if [ $now_epoch -ge $wake_time_epoch ]; then
        break
    fi
    sleep 1
done
while [ 1 ]; do
    say 'wake up'
    sleep 1
done