#!/usr/bin/env bash

function prop () {
  # Needs to be declared before it’s assigned or I cannot grab the exit code 
  # later. Fun race condition <.<
  local selection
  local window
  # Find all visible windows and get their geometry, then
  # format slurp-friendly, then
  # run slurp!
  selection=$(swaymsg -t get_tree | jq  '.. | select(.visible?==true) | .rect | [ .x,.y,.width,.height ]' \
                    | jq -r '"\(.[0]),\(.[1]) \(.[2])x\(.[3])"' \
                    | slurp -r)

  local ret=$?
  [ $ret -ne 0 ] && exit $ret

  local x=$(echo "$selection" | awk -F'[, x]' '{print $1}')
  local y=$(echo "$selection" | awk -F'[, x]' '{print $2}')
  local w=$(echo "$selection" | awk -F'[, x]' '{print $3}')
  local h=$(echo "$selection" | awk -F'[, x]' '{print $4}')

  # Find the window matching the selection.
  window=$(swaymsg -t get_tree | \
      jq ".. | select((.rect?.x==$x) and (.rect?.y==$y) and (.rect?.width==$w) and (.rect?.height=$h) and (.visible?==true))")

  [ -z "$window" ] && exit 1

  # Pretty print, since capturing the output of `swaymsg` makes it uglify.
  echo $window | jq
}

function check_dependencies () {
  local ret=0
  for cmd in "$@"; do
    ! [ $(command -v $cmd) ] && echo "Missing dependency: $cmd." && ret=1
  done
  return $ret
}

( check_dependencies "jq" "slurp" "swaymsg" ) || exit 1

prop