checkmail

#!/bin/bash
count_file=~/.mail/size
count_mailbox() { grep -c -e '^From:' "$1"; }
count_maildir() { find "$1" -type f | wc -l; }
declare -a boxes=($(
	make -C ~/.mail list_mailboxes \
	  | grep ^/ \
	  | grep -v -e trash -e byme
))

now=$(date +%s)
last=$(stat -c %Y $count_file)
age=$(( now-last ))
if [[ $age -ge ${MAILCHECK:-60} ]]; then
	for i in ${boxes[@]}; do
		count=0
		if [[ -f $i ]];   then count=$(count_mailbox "$i");
		elif [[ -d $i ]]; then count=$(count_maildir "$i");
		elif [[ ! -e $i ]]; then count=0
		fi
		echo $count $i
	done
fi > $count_file.new
awk '
{
	c=$1;
	fn=$2;
	paths[fn]++;
	if (paths[fn]==2) {
		if (c > oc[fn]) {
			print "You have ", (c-oc[fn]), "new messages in " fn
		}
	}
	oc[fn]=c;
} ' $count_file $count_file.new > ~/.cache/checkmail
if [[ -s $count_file.new ]]; then
	mv $count_file.new $count_file; fi

### in cron:
## */1    * * * * /home/jaroslav/bin/checkmail
##
### in profile:
##
## _checkmail() { [[ -s ~/.cache/checkmail ]] && cat ~/.cache/checkmail && truncate -s0 ~/.cache/checkmail; }
##  PS1+="${YELLOW}\$(_checkmail && echo \\n)"