#!/bin/sh
# anew checksums -69-
set -e

usage() {
	printf "usage: ${0##*/} %s\n" "[-y] ARCHIVE [SOLTASK-file]"
	exit 1
}
Y=false
while : ; do
 case "$1" in
 -y)
  shift 1
  Y=true
  ;;
 *) break ;;
 esac
done
if [ -z "${1:+s}" ]; then
	usage
fi

l=$(dirname "${1:-.}")
f=$(basename "${1}")
p() { echo "$l/$f"; }
SOL="${2:-$l/SOLTASK}"

p_err() {
 printf "ERR: %s\n" "$@" >&2
 exit 1
}
p_msg() {
 printf "\033[1m=>\033[0m %s\n" "$@" >&2
}
confirm() {(
 printf "overwrite? \033[1m(y/n)\033[0m "
 read REPLY
 case $REPLY in
 y|Y) exit 0 ;;
 *) exit 1 ;;
 esac
)}

if ! [ -f "$(p)" ]; then
 p_err "$(p) : not a file."
fi
if ! [ -f "$SOL" ]; then
 p_err "$SOL : not a file."
fi

g=$(grep '^[^#]*SOLSUM=' "$SOL")\
 || p_err "$SOL contains no SOLSUM=..."
if [ 1 -lt $(echo "$g" |wc -l) ]; then
 p_err "$SOL has redundant SOLSUMs"'
'"$g"
elif echo "$g" |grep -q 'SOLSUM="PASS"'; then
 p_err "$SOL -> SOLSUM=PASS"
fi

SUM=$(sha256sum "$(p)")
SUM="${SUM%% *}"
p_msg "$SUM "''">$SOL"''

#** ** DEN ** **
 #case $? in
 #1) p_err ... ;;
 #2) p_err ... ;;
 #*) p_err "status unknown" ;;
 #esac
#** ** END ** **

a=$(sed 's:^[^#]*SOLSUM=.*:SOLSUM="'"$SUM"'":' "$SOL")
if ! $Y; then
 echo "$a" >&2
 confirm
fi
echo "$a" >"$SOL"