#!/usr/bin/env bash

# originally got the idea from this script:
# src:https://github.com/veltall/custom-i3lock

# get random image to use
# https://stackoverflow.com/questions/61290199/how-do-i-select-a-random-file-from-a-directory
random_image=$(ls -1 /home/${USER}/.local/share/img/*.png |  shuf | head -1)
random_image_filname="$(basename -- $random_image)"

# get random gravity to use for the overlay image
gravity=("northeast" "southeast") # "center" "northwest" "northeast" "southwest" "southeast"
random_gravity=${gravity[ $RANDOM % ${#gravity[@]} ]}

# send a notification to the user
notify-send "${random_image_filname} @ ${random_gravity}"

# take a screenshot of the entire screen, and blur this
scrot --overwrite /tmp/currentworkspace.png
magick /tmp/currentworkspace.png -blur 0x9 /tmp/currentworkspaceblur.png

# find height of background image, and set the overlay to be 1/3 of this
workspaceHeight=$(magick /tmp/currentworkspaceblur.png -print "%h" /dev/null)
overlayHeight=$((${workspaceHeight} / 3))

# resize the overlay image
cp ${random_image} /tmp/overlayimage.png
mogrify -resize x${overlayHeight} /tmp/overlayimage.png

# create the final image to be used as the lock screen, and lock the system
composite -gravity ${random_gravity} /tmp/overlayimage.png /tmp/currentworkspaceblur.png /tmp/lockbackground.png
i3lock --tiling -i /tmp/lockbackground.png