gitsyncroot-nomsg-periodic

#!/bin/bash
# Author: Gokberk Cinbis, May 2020 

# set -e --> dont do this since (i) incompatible with wait() [needs special handling] and (ii) breaks down the script in case of temp I/O errors
shopt -s expand_aliases

# -- copy pasted from bashrc-defs for portability --
# this way:
# * the script doesn't require .bashrc, to be used in Makefile, etc. more easily
# * this becomes a standalone script with fewer dependencies 
alias gitsyncroot-nomsg='(command cd `git-print-root-path` && __gitsync-nomsg)' 
alias git-print-root-path='git rev-parse --show-toplevel'
alias __gitsync-nomsg='(git reset && git add . && git-commit-silent-nomsg && echo "git-pull-nomsg & git push" && git-pull-nomsg && git push)' # pull and send
function git-commit-silent-nomsg() {
    d=`command date +%Y%m%d`
    t=`command date +%H.%M.%S` # hour.minute.seconds (dots are useful for time, otherwise very unreadible)
    #host=`command hostname`
    #msg_="$host-$d-$t" # -- host can be sensitive, avoid it --
    msg_="NoMessage-$d-$t" # -- host can be sensitive, avoid it --
    git diff-index --quiet HEAD || git commit -m "$msg_" # no error signal if there is nothing to commit
}
alias git-pull-nomsg='git pull --no-edit'

function __main__()
{
    if [[ "$#" != 1 ]]; then
        echo 'gitsyncroot-nomsg-periodic <NumUpdatesPerHour>'
        echo 'Periodically run gitsyncroot-nomsg in the current repository.'
        echo "Error: invalid number of input arguments ($#)"
        return 1
    else
        let sleep_seconds=3600/$1
        echo "Running gitsyncroot-nomsg-periodic at $PWD" 
        while true; do 
            gitsyncroot-nomsg
            last_time="$(command date -u +%s)"
            echo "Running gitsyncroot-nomsg-periodic at $PWD" 
            echo "" # readability
            printf "Last update: "
            date
            echo "Running $1 times per hour, every $sleep_seconds seconds."
            while true; do
                # Simpler alternative: command sleep 10 
                command read -t 10 -n 1 # sleep n seconds for polling (suggested=10)
                if [ $? = 0 ] ; then
                    break
                fi
                cur_time="$(command date -u +%s)"
                delta="$(($cur_time-$last_time))"
                if [ "$delta" -ge $sleep_seconds ]; then break; fi # time to update
                remain="$(($sleep_seconds-$delta))"
                command printf "Next run in %6d seconds (press a key to start immediately)\r" "$remain"
            done
        done
    fi
}

# ok with multiple quoted arguments
__main__ "$@"