[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 - $SCRIPT_RUN_DATE_SECONDS )/86400 ))" days" # Days until next discontinuity date
Commit	Line	Data
fdf917e1 SBS	1	#!/bin/bash
	2
	3	# Date: 2020-02-13T23:14Z; baltakatei>
	4
	5	# Description: This script outputs days until the next time zone
	6	# discontinuity using 'zdump' and 'date'.
	7
	8	#=================ADJUST ME=======================
	9	SCRIPT_TZ="America/Los_Angeles" # Timezone to check for discontinuities
	10	#=================================================
	11
	12	echoerr() {
	13	echo "$@" 1>&2;
	14	}
	15
	16	# Declare variables
	17	declare -a datesDiscontArray #array
	18
	19	SCRIPT_YEAR=$(date +%Y)
	20	SCRIPT_YEAR_NEXT=$(( $(date +%Y) + 1))
	21	SCRIPT_RUN_DATE_SECONDS=$(date +%s)
	22
	23	# Save zdump output for SCRIPT_YEAR (for how multiline data saved in variable, see https://stackoverflow.com/a/613580 )
	24	datesDiscont="$(zdump -c $SCRIPT_YEAR_NEXT -v $SCRIPT_TZ \| grep $SCRIPT_YEAR \| awk '{ print $2 " " $3 " " $4 " " $5 " " $6 " " $7 }'; echo)"
	25	if [ -z "$datesDiscont" ]; then
	26	echo "No time discontinuity this year."
	27	exit 1
	28	fi
	29
	30	###echoerr "datesDiscont:--""$datesDiscont""--"
	31
	32	# Count lines in datesDiscont (for counting lines in a variable, see https://stackoverflow.com/a/6314682 )
	33	#datesDiscontLineCount=$(echo "$datesDiscont" \| wc -l)
	34
	35	# Convert datesDiscont into array (for how to process each line in a multiline variable, see https://superuser.com/a/284226 )
	36	while IFS= read -r line; do
	37	#echo "$line"
	38	#datesDiscontArray+="$line"
	39	datesDiscontArray+=($(date --date="$line" +%s))
	40	#echo ${datesDiscontArray[-1]}
	41	done <<< "$datesDiscont"
	42	#echoerr ${datesDiscontArray[@]}
	43
	44	# Sort datesDiscontArray (see https://stackoverflow.com/a/11789688 )
	45	IFS=$'\n' datesDiscontArray=($(sort <<<"${datesDiscontArray[*]}"))
	46	unset IFS
	47
	48	# Get earliest date in datesDiscontArray that isn't in the past.
	49	for discontinuityDate in "${datesDiscontArray[@]}"; do
	50	###echoerr "Discontinuity date (seconds):"$discontinuityDate
	51	###echoerr "SCRIPT_RUN_DATE_SECONDS :"$SCRIPT_RUN_DATE_SECONDS
	52	if [ $discontinuityDate -gt $SCRIPT_RUN_DATE_SECONDS ]; then
	53	###echoerr "DEBUG:Date in future."
	54	nextDiscontDate="$discontinuityDate"
	55	break
	56	fi
	57	done
	58
	59	echo $(( ( $nextDiscontDate - $SCRIPT_RUN_DATE_SECONDS )/86400 ))" days" # Days until next discontinuity date