stupid script for updating AUR packages

#!/bin/bash

if [ "$#" -ne 1 ]; then
    echo "Usage: "$(basename $0)" aur_package_dir"
    echo
    echo "This is a stupid and simple AUR package upgrader"
    echo
    echo "When passed a directory where clones of AUR repositories are this script"
    echo "will iterate over them directory by directory and if any contains"
    echo "a PKGBUILD file with pkgbase/pkgname will see if this package is installed."
    echo "If it is will perform git reset --hard + git pull, check for pkgver/pkgrel"
    echo "against what is installed and call makepkg -sri in case they differ"
    echo
    echo 'Unfortunately you still have to type your sudo password when installing'
    echo 'packages and I still do not know how to workaround this'a
    exit 1
fi

pushd $1 > /dev/null

for dir in */; do
    pushd $dir > /dev/null

    if [ -f PKGBUILD ]; then
        pkgbase=$(grep -m 1 pkgbase PKGBUILD | cut -d '=' -f 2)
        pkgname=$(grep -m 1 pkgname PKGBUILD | cut -d '=' -f 2)

        # If we have a base package, check for it, using makepkg -sri anyway to install everything
        if [ ! -z $pkgbase ]; then
            pkgname=$pkgbase
        fi

        # In split packages "If pkgbase is not specified, the first element in the pkgname array is used."
        # (c) https://wiki.archlinux.org/index.php/PKGBUILD#Package_name
        # so get the first element of an array if needed
        if echo $pkgname | grep "^("; then
            pkgname=`echo $pkgname | cut -d ' '  -f 1`
            pkgname=${pkgname:2}
        fi

        if [ ! -z "$pkgname" ]; then
            pkg_info=$(pacman -Qi $pkgname 2>&1)
            if [ $? -eq 0 ]; then
                inst_version=`echo "$pkg_info" | grep -m 1 Version | sed s'/Version         ://g' | xargs`
                if echo $inst_version | grep ':'; then
                    inst_version=`echo $inst_version | rev | cut -d ':' -f 1 | rev`
                fi
                echo "--- Found installed package "$pkgname" version: "$inst_version

                git reset --hard
                git pull

                pkgver=$(grep -m 1 pkgver PKGBUILD | cut -d '=' -f 2 | xargs)
                pkgrel=$(grep -m 1 pkgrel PKGBUILD | cut -d '=' -f 2 | xargs)
                git_version=${pkgver}"-"${pkgrel}
                echo "------ Git version of this package is "$git_version

                if [ "$inst_version" != "$git_version" ]; then
                    echo "--------- Package "$pkgname" installed version "$inst_version" has git version "$git_version", will reinstall"
                    makepkg --noconfirm -sri
                fi
            fi
        fi
    fi

    popd > /dev/null
done

popd > /dev/null