feat(unitprod):Created timeDuration function template

[BK-2020-03.git] / unitproc / bkdstcountdown

#!/bin/bash

# Date: 2020-02-13T23:14Z; baltakatei>

# Description: This script outputs days until the next time zone
# discontinuity using 'zdump' and 'date'.

#=================ADJUST ME=======================
SCRIPT_TZ="America/Los_Angeles" # Timezone to check for discontinuities
#=================================================

echoerr() {
    echo "$@" 1>&2;
}

# Declare variables
declare -a datesDiscontArray #array

SCRIPT_YEAR=$(date +%Y)
SCRIPT_YEAR_NEXT=$(( $(date +%Y) + 1))
SCRIPT_RUN_DATE_SECONDS=$(date +%s)

# Save zdump output for SCRIPT_YEAR (for how multiline data saved in variable, see https://stackoverflow.com/a/613580 )
datesDiscont="$(zdump -c $SCRIPT_YEAR_NEXT -v $SCRIPT_TZ | grep $SCRIPT_YEAR |  awk '{ print $2 " " $3 " " $4 " " $5 " " $6 " " $7 }'; echo)"
if [ -z "$datesDiscont" ]; then
    echo "No time discontinuity this year."
    exit 1
fi

###echoerr "datesDiscont:--""$datesDiscont""--"

# Count lines in datesDiscont (for counting lines in a variable, see https://stackoverflow.com/a/6314682 )
#datesDiscontLineCount=$(echo "$datesDiscont" | wc -l)

# Convert datesDiscont into array (for how to process each line in a multiline variable, see https://superuser.com/a/284226 )
while IFS= read -r line; do
    #echo "$line"
    #datesDiscontArray+="$line"
    datesDiscontArray+=($(date --date="$line" +%s))
    #echo ${datesDiscontArray[-1]}
done <<< "$datesDiscont"
#echoerr ${datesDiscontArray[@]}

# Sort datesDiscontArray (see https://stackoverflow.com/a/11789688 )
IFS=$'\n' datesDiscontArray=($(sort <<<"${datesDiscontArray[*]}"))
unset IFS

# Get earliest date in datesDiscontArray that isn't in the past.
for discontinuityDate in "${datesDiscontArray[@]}"; do
    ###echoerr "Discontinuity date (seconds):"$discontinuityDate
    ###echoerr "SCRIPT_RUN_DATE_SECONDS     :"$SCRIPT_RUN_DATE_SECONDS
    if [ $discontinuityDate -gt $SCRIPT_RUN_DATE_SECONDS ]; then
	###echoerr "DEBUG:Date in future."
	nextDiscontDate="$discontinuityDate"
	break
    fi
done

echo $(( ( $nextDiscontDate - $SCRIPT_RUN_DATE_SECONDS )/86400 ))" days" # Days until next discontinuity date