#!/usr/bin/env bash

export LC_ALL=C

tmpdir="$(mktemp -d)"

cp ../../{rgbfix,contrib/gbdiff.bash} "$tmpdir"
src="$PWD"
cd "$tmpdir" || exit

# Immediate expansion is the desired behavior.
# shellcheck disable=SC2064
trap "cd; rm -rf ${tmpdir@Q}" EXIT

tests=0
failed=0
rc=0

bold="$(tput bold)"
resbold="$(tput sgr0)"
red="$(tput setaf 1)"
green="$(tput setaf 2)"
rescolors="$(tput op)"

RGBFIX=./rgbfix

tryDiff () {
	if ! diff -au --strip-trailing-cr "$1" "$2"; then
		echo "${bold}${red}${3:-$1} mismatch!${rescolors}${resbold}"
		false
	fi
}

tryCmp () {
	if ! cmp "$1" "$2"; then
		./gbdiff.bash "$1" "$2"
		echo "${bold}${red}${3:-$1} mismatch!${rescolors}${resbold}"
		false
	fi
}

runTest () {
	flags=$(
		head -n 1 "$2/$1.flags" | # Allow other lines to serve as comments
		sed "s# ./# ${src//#/\\#}/#g" # Prepend src directory to path arguments
	)

	for variant in '' ' piped'; do
		(( tests++ ))
		our_rc=0
		if [[ $progress -ne 0 ]]; then
			echo "${bold}${green}$1${variant}...${rescolors}${resbold}"
		fi
		if [[ -r "$2/$1.bin" ]]; then
			desired_input="$2/$1.bin"
		else
			desired_input="$src/default-input.bin"
		fi
		if [[ -z "$variant" ]]; then
			cp "$desired_input" out.gb
			if [[ -n "$(eval "$RGBFIX" $flags out.gb '2>out.err')" ]]; then
				echo "${bold}${red}Fixing $1 in-place shouldn't output anything on stdout!${rescolors}${resbold}"
				our_rc=1
			fi
			subst=out.gb
		else
			# Stop! This is not a Useless Use Of Cat. Using cat instead of
			# stdin redirection makes the input an unseekable pipe - a scenario
			# that's harder to deal with.
			# shellcheck disable=SC2002
			cat "$desired_input" | eval $RGBFIX "$flags" - '>out.gb' '2>out.err'
			subst='<stdin>'
		fi

		if [[ -r "$2/$1.err" ]]; then
			desired_errname="$2/$1.err"
		else
			desired_errname=/dev/null
		fi
		sed "s/$subst/<filename>/g" out.err | tryDiff "$desired_errname" - "$1.err${variant}"
		(( our_rc = our_rc || $? ))

		if [[ -r "$2/$1.gb" ]]; then
			tryCmp "$2/$1.gb" out.gb "$1.gb${variant}"
			(( our_rc = our_rc || $? ))
		fi

		(( rc = rc || our_rc ))
		if [[ $our_rc -ne 0 ]]; then
			(( failed++ ))
			break
		fi
	done
}

rm -f padding*_* # Delete padding test cases generated but not deleted (e.g. interrupted)

progress=1
for i in "$src"/*.flags; do
	runTest "$(basename "$i" .flags)" "$src"
done

# Check the result with all different padding bytes
echo "${bold}Checking padding...${resbold}"
cp "$src"/padding{,-large,-larger}.bin .
touch padding{,-large,-larger}.err
progress=0
for (( i=0; i < 10; ++i )); do
	(( padding = RANDOM % 256 ))
	echo "$padding..."
	for suffix in '' -large -larger; do
		cat <<<"-p $padding" >padding$suffix.flags
		tr '\377' \\$((padding / 64))$(((padding / 8) % 8))$((padding % 8)) <"$src/padding$suffix.gb" >padding$suffix.gb # OK because $FF bytes are only used for padding
		runTest padding${suffix} .
	done
done
echo "${bold}Done checking padding!${resbold}"

# Check that RGBFIX errors out when inputting a non-existent file...
$RGBFIX noexist 2>out.err
rc=$((rc || $? != 1))
tryDiff "$src/noexist.err" out.err noexist.err
rc=$((rc || $?))

if [[ "$failed" -eq 0 ]]; then
	echo "${bold}${green}All ${tests} tests passed!${rescolors}${resbold}"
else
	echo "${bold}${red}${failed} of the tests failed!${rescolors}${resbold}"
fi

exit $rc