Pre-commit hook to bump version number

pre-commit

#!/bin/sh
# Standard WUSM version numbering:
# year.month.day.commit
#
# This script searches all files in the git repo
# and bumps the version number

new=$(date +"%y.%m.%d.0")
a=( ${new//./ } )
file=$(grep -lir "Version:" *.php)
while read -r line
do
    if  [[ $line == *Version:* ]];
    then
        old=$line
	c=${line#Version:}
        b=( ${c//./ } )
        if [ ${a[0]} == ${b[0]}  ] && [ ${a[1]} == ${b[1]} ] && [ ${a[2]} == ${b[2]}  ]; then
            # already had a commit today, just bump commit number
            ((b[3]++))
            new="${a[0]}.${a[1]}.${a[2]}.${b[3]}"
        else
            # first commit of the day
            new="${a[0]}.${a[1]}.${a[2]}.0"
        fi
    fi
done <$file

find_this=$c
replace_with=$new

echo "Incrementing version from $c to $new\n"

ag -l $find_this $* | xargs sed -i '' "s/$find_this/$replace_with/g"

#this is kinda annoying, but it works
git add .