pacmanfile

#!/bin/bash

set -u

usage_msg='
NAME:
  pacmanfile - Manage your pacman packages declaratively

SYNOPSIS:
  pacmanfile <operations> [options]

OPERATIONS:
  help   Show this help
  dump   Dump your installed packages into a pacmanfile
  sync   Synchronize your installed packages with your pacmanfile

OPTIONS:
  --noconfirm   Install and uninstall without asking for confirmation
'

package_manager=pacman
if [ -x "$(command -v yay)" ]; then
    package_manager=yay
fi
if [ -x "$(command -v paru)" ]; then
    package_manager=paru
fi

config_dir=${XDG_CONFIG_HOME:-$HOME/.config}
pacmanfile_dir="${config_dir}/pacmanfile"

# Parse arguments
operation=help
option_confirm='--confirm'

while [[ $# -gt 0 ]]; do
    key="$1"

    case $key in
    dump)
        operation=dump
        shift
        ;;

    sync)
        operation=sync
        shift
        ;;

    --noconfirm)
        option_confirm='--noconfirm'
        shift
        ;;

    *)
        shift
        ;;
    esac
done

function dump {
    dump_file="${pacmanfile_dir}/pacmanfile-dumped.txt"
    installed_packages=$($package_manager --query --explicit --quiet | sort --unique)

    # Create config folder if not present
    if [ ! -d "$pacmanfile_dir" ]; then
        mkdir --parents "$pacmanfile_dir"
    fi

    echo "$installed_packages" >"$dump_file"

    echo "Installed packages dumped to $dump_file"
}

function sync {
    pacmanfile_packages=$(sort --unique "${pacmanfile_dir}"/pacmanfile*.txt | grep -E '^[^#].*')
    installed_packages=$($package_manager --query --explicit --quiet | sort --unique)

    to_install=$(diff --new-line-format="" --unchanged-line-format="" <(echo "$pacmanfile_packages") <(echo "$installed_packages"))
    if [ -n "$to_install" ]; then
        # shellcheck disable=SC2086
        $package_manager "$option_confirm" --sync --needed $to_install
    fi

    to_remove=$(diff --new-line-format="" --unchanged-line-format="" <(echo "$installed_packages") <(echo "$pacmanfile_packages"))
    if [ -n "$to_remove" ]; then
        # shellcheck disable=SC2086
        $package_manager "$option_confirm" --remove --nosave --recursive $to_remove
    fi

    if [ -z "$to_install" ] && [ -z "$to_remove" ]; then
        echo "Everything is synced"
    fi
}

case $operation in
dump)
    dump "$@"
    ;;

sync)
    sync "$@"
    ;;

help)
    echo "$usage_msg"
    exit 0
    ;;

*)
    echo "$usage_msg"
    exit 1
    ;;
esac