#!/bin/sh -euf
#
# Convert input to 32bit hex encoded utf8.
#
# Copyright (c) 2026 Dylan Araps
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
#

export LC_ALL=C
a=$1; b=${a#?}; c=${b#?}; d=${c#?}
unset LC_ALL
a=${a%"$b"} b=${b%"$c"} c=${c%"$d"} d=${d%"${1#????}"}
export $(printf 'a=%d b=%d c=%d d=%d' "'$a" "'$b" "'$c" "'$d")
printf '0x%08X\n' "$((a < 128 ? a : a < 224 ?
(a & 0x1F) <<  6 | (b & 0x3F) : a < 240 ?
(a & 0x0F) << 12 | (b & 0x3F) <<  6 | (c & 0x3F) :
(a & 0x07) << 18 | (b & 0x3F) << 12 | (c & 0x3F) << 6 | (d & 0x3f)))"