replace_baseplate.sh

#!/bin/bash

replace_baseplate_circle () {

if ! [ -e "${1}" ]; then
    return 1
fi

grep -qE '^  <linearGradient id="linearGradient[0-9]*" x1="1" x2="47" gradientUnits="userSpaceOnUse">$' < "${1}" || return 1

grep -qE '^ <g transform="matrix\(0,-1,1,0,0,48\)' < "${1}" || return 1

local __gradient_number="$(grep -E '^  <linearGradient id="linearGradient[0-9]*" x1="1" x2="47" gradientUnits="userSpaceOnUse">' < "${1}" | grep -oE 'id="linearGradient[0-9]*"' | sed 's/^id="linearGradient\([0-9]*\)"$/\1/')"

sed \
-e 's/  <linearGradient id="linearGradient\([0-9]*\)" x1="1" x2="47" gradientUnits="userSpaceOnUse">/  <linearGradient id="linearGradient\1" x2="0" y1="47" y2="1" gradientUnits="userSpaceOnUse">/' \
-i "${1}"

perl -i -p0e 's/ <g transform="matrix\(0,-1,1,0,0,48\)".*? <\/g>/ <circle cx="24" cy="24" r="23" style="fill:url\(#GRADIENT_TEMPORARY\)"\/>/s' "${1}"

sed -e "s/GRADIENT_TEMPORARY/linearGradient${__gradient_number}/" -i "${1}"

echo "${1}"

}

replace_baseplate_square () {

if ! [ -e "${1}" ]; then
    return 1
fi

grep -qE '^  <linearGradient id="linearGradient[0-9]*" x1="-47" x2="-1" y1="2.8779e-15" y2="6.1232e-17" gradientUnits="userSpaceOnUse">$' < "${1}" || return 1

grep -qE '^ <rect transform="rotate\(-90\)" x="-47" y="1" width="46" height="46" rx="4" style="fill:url\(#linearGradient[0-9]*\)' < "${1}" || return 1

pcregrep -qM ' <g transform="translate\(0 3.949e-5\)">
  <path d="m1 43v0.25c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-0.25c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4zm0 0.5v0.5c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-0.5c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4z" style="opacity:.02"\/>
  <path d="m1 43.25v0.25c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-0.25c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4z" style="opacity:.05"\/>
  <path d="m1 43v0.25c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-0.25c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4z" style="opacity:.1"\/>
 <\/g>' < "${1}" || return 1

pcregrep -qM ' <g transform="translate\(0 3.949e-5\)">
  <g transform="translate\(0 -1004.4\)">
   <path d="m1 1043.4v4c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-4c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4z" style="opacity:.1"\/>
  <\/g>
 <\/g>' < "${1}" || return 1

local __gradient_number="$(grep -E '^  <linearGradient id="linearGradient[0-9]*" x1="-47" x2="-1" y1="2.8779e-15" y2="6.1232e-17" gradientUnits="userSpaceOnUse">' < "${1}" | grep -oE 'id="linearGradient[0-9]*"' | sed 's/^id="linearGradient\([0-9]*\)"$/\1/')"

sed \
-e 's/ y1="2.8779e-15" y2="6.1232e-17" / /' \
-e 's/  <linearGradient id="linearGradient\([0-9]*\)" x1="-47" x2="-1" gradientUnits="userSpaceOnUse">/  <linearGradient id="linearGradient\1" x2="0" y1="47" y2="1" gradientUnits="userSpaceOnUse">/' \
-e 's/ <rect transform="rotate(-90)" x="-47" y="1" width="46" height="46" rx="4" style="fill:url(#linearGradient\([0-9]*\))"\/>/ <rect x="1" y="1" width="46" height="46" rx="4" style="fill:url(#linearGradient\1)"\/>/' \
-i "${1}"

perl -i -p0e 's/ <g transform="translate\(0 3.949e-5\)">
  <path d="m1 43v0.25c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-0.25c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4zm0 0.5v0.5c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-0.5c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4z" style="opacity:.02"\/>
  <path d="m1 43.25v0.25c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-0.25c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4z" style="opacity:.05"\/>
  <path d="m1 43v0.25c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-0.25c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4z" style="opacity:.1"\/>
 <\/g>/ <path d="m1 43v0.25c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-0.25c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4zm0 0.5v0.5c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-0.5c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4z" style="opacity:.02"\/>
 <path d="m1 43.25v0.25c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-0.25c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4z" style="opacity:.05"\/>
 <path d="m1 43v0.25c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-0.25c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4z" style="opacity:.1"\/>/s' "${1}"

perl -i -p0e 's/ <g transform="translate\(0 3.949e-5\)">
  <g transform="translate\(0 -1004.4\)">
   <path d="m1 1043.4v4c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-4c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4z" style="opacity:.1"\/>
  <\/g>
 <\/g>/ <path d="m1 39v4c0 2.216 1.784 4 4 4h38c2.216 0 4-1.784 4-4v-4c0 2.216-1.784 4-4 4h-38c-2.216 0-4-1.784-4-4z" style="opacity:.1"\/>/s' "${1}"


sed -e "s/GRADIENT_TEMPORARY/linearGradient${__gradient_number}/" -i "${1}"

echo "${1}"

}

all_circle () {

find icons/circle/48/ -type f | sort | while read -r __file; do
    replace_baseplate_circle "${__file}" &
done

}

all_square () {

find icons/square/48/ -type f | sort | while read -r __file; do
    replace_baseplate_square "${__file}" &
done

}

if [ "${#}" = '0' ]; then

    all_circle

    all_square

    wait

else

    until [ "${#}" = '0' ]; do
        if [ -e "icons/circle/48/${1}.svg" ]; then
            replace_baseplate_circle "icons/circle/48/${1}.svg"
        fi
        if [ -e "icons/square/48/${1}.svg" ]; then
            replace_baseplate_square "icons/square/48/${1}.svg"
        fi
        shift
    done

fi

exit