#!/bin/sh

# The MIT License (MIT)
#
# Copyright (c) 2026 pacman64
#
# 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.


# same [options...] [file 1] [file 2]
#
#
# Check if 2 files have the same contents. Output is emitted only for errors,
# and only on the standard error, if so.
#
# This tool is used for its return code, which is 0 when the files have the
# same contents, 1 when they don't, or 2 when not given exactly 2 files to
# compare, or if either file isn't found.
#
# The options are, available both in single and double-dash versions
#
#   -h, -help    show this help message


case "$1" in
    -h|--h|-help|--help)
        awk '/^# +same /, /^$/ { gsub(/^# ?/, ""); print }' "$0"
        exit 0
    ;;

    -) ;;

    --) shift ;;

    -*)
        printf "unsupported option '%s'\n" "$1" >&2
        exit 2
    ;;
esac

if [ $# -ne 2 ]; then
    printf "given %d files, instead of 2\n" "$#" >&2
    exit 2
fi

if [ ! -e "$1" ]; then
    printf "file named '%s' not found\n" "$1" >&2
    exit 2
fi
if [ ! -e "$2" ]; then
    printf "file named '%s' not found\n" "$2" >&2
    exit 2
fi

diff -q "$1" "$2" > /dev/null