#!/bin/sh

set -e

cd "${0%/*}"
exec 2>&1

check() {
    for arg in $1; do
        read -r line || { echo "FAIL: insufficient output" >&2; return 1; }
        echo "GOT: $line"
        case "$arg" in
            [a-z]) case "$line" in "in $arg "*) ;; *) echo "FAIL: expected $arg" >&2; return 1; esac;;
            err) case "$line" in nextbin*failed*) ;; *) echo "FAIL: expected err" >&2; return 1; esac;;
            *) echo "INVALID TEST" >&2; exit 1
        esac
    done
    if read -r line; then
        echo "FAIL: too much output" >&2
        return 1
    fi
    echo "OK"
}

try() {
    # shellcheck disable=SC2016
    printf 'TEST: PATH="%s:$PATH:%s" %s, expect %s\n' "${PWD%/test}" "$@"
    PATH="$PATH:$1" "$2" 2>&1 | check "$3"
    # shellcheck disable=SC2016
    printf 'TEST: PATH="%s:%s:$PATH" %s, expect %s\n' "${PWD%/test}" "$@"
    PATH="$1:$PATH" "$2" 2>&1 | check "$3"
}

do_try() {
    try "$1" "$2/x" "$3"
    try "$1" "$2//x" "$3"
    try "$1" "./$2/x" "$3"
    try "$1" "$PWD/$2/x" "$3"
    try "$1" "$2/../$2/x" "$3"
    try "$1" "./$2/../$2/x" "$3"
    try "$1" "$PWD/$2/../$2/x" "$3"
    echo
}

# use do_try2 if x in PATH
do_try2() {
    try "$1" "x" "$3"
    do_try "$@"
}

export PATH="${PWD%/test}:$PATH"

do_try "" a "a err"
do_try2 "$PWD/a" a "a err"
do_try "$PWD/b" a "a b err"
do_try2 "$PWD/a:$PWD/b" a "a b err"
do_try "$PWD/a:$PWD/b" b "b err"
do_try2 "$PWD/a:$PWD/b:$PWD/c" a "a b c"
do_try "$PWD/a:$PWD/b:$PWD/c" b "b c"
do_try2 "$PWD/a:$PWD/a" a "a err"

echo "ALL TESTS COMPLETED SUCCESSFULLY :)"