yay paccache hooks

pacman_yay_clean_cache.hook

[Trigger]
Operation = Upgrade
Type = Package
Target = *

[Action]
Description = Clearing old cache...
When = PostTransaction
Exec = <path_to_script>/pacman_yay_clean_cache.sh

pacman_yay_clean_cache.sh

#!/bin/sh
#
# Clean cache pacman & yay script
#

## TODO: Auto get pacman cachedir (can be changed)
#        Idea: extract from pacman.conf? 
PACMAN_CACHE_DIR=/var/cache/pacman/pkg

## TODO: Check if yay is installed(if no, skip), 
#        then check if yaycachedir is changed, 
#        if not, use default ~/.cache/yay
YAY_CACHE_DIR=/home/$USER/.cache/yay

# Unlike pacman, yay splits cache to dirs by pkg name
# add '-c' before path for paccache: 
# -c, --cachedir <dir>  scan "dir" for packages. can be used more than once.
cache_dirs="$(find $YAY_CACHE_DIR -maxdepth 1 -type d | awk '{ print "-c " $1 }' | tail -n +2)"

# add pacman cache dir
cache_dirs+=" -c $PACMAN_CACHE_DIR"

# clean 
echo "==> Keep last 3 installed versions"
paccache -rk3 $cache_dirs
echo "==> Remove cache of uninstalled pkgs"
paccache -ruk0 $cache_dirs