#!/bin/bash

set -e

tests=()

update=0

while [ $# -gt 1 ]; do
	case "$1" in
		--update-expected|-u)
			update=1
			shift
		;;
		--test|-t)
			shift
			tests+=($1)
			shift
		;;
		*)
			break
		;;
	esac
done

if [ -z "$1" ]; then
	echo "Usage: $0 [-u|--update-expected] [(-t|--test) <test-set>]... <program> [<program args>...]"
	exit 1
fi

if [ ${#tests[@]} -eq 0 ]; then
	tests=(parse)
fi

program="$@"

testdir="$(dirname "$0")/sets"

total_passed=0
total_failed=0

pass() {
	echo -e "\r[\033[1;32mPASS\033[m]"
	((passed++))
	((total_passed++))
}

fail() {
	echo -e "\r[\033[1;31mFAIL\033[m]"
	((failed++))
	((total_failed++))
}

diff='git -c color.diff.old=green -c color.diff.new=red --no-pager diff -U1 --no-index --color --exit-code'

set +e

for dir in "${tests[@]}"; do

	passed=0
	failed=0

	if [ -d "$testdir/$dir/tests" ]; then

		outputdir="$testdir/$dir/.output"
		diffdir="$testdir/$dir/.diff"

		rm -rf "$outputdir" "$diffdir"
		mkdir "$outputdir" "$diffdir"

		if [ -f "$testdir/$dir/flags" ]; then
			flags="$(<"$testdir/$dir/flags" )"
		else
			flags=''
		fi

		for testfile in "$testdir/$dir/tests"/*; do
			testname="${testfile##*/}"
			expectedfile="$testdir/$dir/expected/$testname"
			outputfile="$outputdir/$testname"
			difffile="$diffdir/$testname"
			echo -n "[....] $dir/$testname"
			{ $program $flags "$testfile"; } &> $outputfile
			r=$?
			if [ $r != 0 ]; then
				fail
				echo -e "\033[31mProgram exited with non-zero status code ($r). The output was:\033[m"
				cat "$outputfile"
				echo -e "\033[31mProgram was invoked as: $program $flags \"$testfile\"\033[m"
			elif [ $update == 1 ]; then
				pass
				cp "$outputfile" "$expectedfile"
			elif [ ! -f "$expectedfile" ]; then
				echo -e "\r[\033[1;34m????\033[m] $dir/$testname - no expected output available, got:"
				cat "$outputfile"
			elif $diff "$expectedfile" "$outputfile" > "$difffile"; then
				pass
			else
				fail
				tail -n+5 "$difffile"
			fi
		done

	else

		echo -n "[....] No such directory: $testdir/$dir/tests"
		fail

	fi

	if [ ${#tests[@]} -gt 1 ]; then
		if [ $failed -gt 0 ]; then
			echo -e "[\033[1;31m$failed $dir TEST(S) FAILED\033[m]\n";
		else
			echo -e "[\033[1;32mALL $passed $dir TESTS PASSED\033[m]\n";
		fi
	fi

done

if [ $total_failed -gt 0 ]; then
	echo -e "[\033[1;31m$total_failed TEST(S) FAILED\033[m]";
	exit 1
else
	echo -e "[\033[1;32mALL $total_passed TESTS PASSED\033[m]";
	exit 0
fi