#!/bin/bash
#
# rest_test.sh — Regression tests for the bar structure of a rest argument.
#
# A rest argument collects everything after the declared positional
# arguments, bars included, and hands the structure on; a klammer reads the
# bar count as dimension (| elements, || rows).  The one thing the ENGINE
# decides is where the structure begins and ends:
#
#   * exactly ONE written leading bar is stripped — the bar that separates
#     the rest from what precedes it: the last positional argument, the
#     options, or the klammer name in the opening-bar idiom (`@table |` with
#     the rows on the lines below).  Every further leading bar delimits an
#     EMPTY FIRST ELEMENT the writer meant: `@table | | M | F ||` has an
#     empty corner cell.  Decided 2026-10-01; before it every leading bar
#     was trimmed, so an empty first element could not be written at all,
#     and a Markdown table's empty header corner shifted the header row one
#     column left.
#   * trailing bars and whitespace are trimmed (the customary dangling
#     separator before a closing @), as before.
#   * an empty element between two bars is kept wherever it stands.
#
# The rest(N) cast (kutil.rest_split) is SKS Python and is tested at that
# tier; here the value is read back raw through *name* substitution.
#
# Engine tier: --klammersets none, fixtures inline.
#
# Usage: ./rest_test.sh   (LSan suppressions come from env/runtime.env)
# Exit code: 0 if all tests pass, 1 otherwise.

PASS=0
FAIL=0
KTEXT=ktext
K=${KLAMMERTEXT_HOME:?KLAMMERTEXT_HOME must be set}

red=$'\033[31m'
green=$'\033[32m'
reset=$'\033[0m'

trim() { awk '{ sub(/[ \t\r]+$/, "") } { line[NR]=$0 } END { f=1; while (f<=NR && line[f]=="") f++; l=NR; while (l>=1 && line[l]=="") l--; for (i=f;i<=l;i++) print line[i] }'; }

# check_eq TEST_NAME EXPECTED INPUT
#   The fixtures: @zz takes only a rest, @yy one positional then a rest.
#   Each prints its arguments in brackets, so the bar structure is visible.
check_eq() {
    local test_name="$1" expected="$2" input="$3"
    local output status
    output=$("$KTEXT" --klammersets none -d -s "@@zz items.rest :x 0 : [*items*] @@ @@yy first | second.rest : [*first*][*second*] @@ $input" 2>/tmp/rest_test_err.$$)
    status=$?
    output=$(printf '%s' "$output" | trim)
    if [ $status -ne 0 ]; then
        echo "${red}FAIL${reset} $test_name — ktext exited $status"
        echo "       stderr: $(head -3 /tmp/rest_test_err.$$)"
        FAIL=$((FAIL + 1))
        return
    fi
    if [ "$output" = "$expected" ]; then
        echo "${green}PASS${reset} $test_name"
        PASS=$((PASS + 1))
    else
        echo "${red}FAIL${reset} $test_name"
        echo "       expected: [$expected]"
        echo "       got:      [$output]"
        FAIL=$((FAIL + 1))
    fi
}

echo "-- the leading bar --"
check_eq " 1. no leading bar: the elements as written"          '[M | F]'     '@zz M | F @'
check_eq " 2. the opening-bar idiom: one bar stripped"           '[M | F]'     '@zz | M | F @'
check_eq " 3. a second leading bar is an empty first element"   '[| M | F]'   '@zz | | M | F @'
check_eq " 4. the idiom with the rows below, empty corner cell" '[| M | F ||
Nom | der]' '@zz |
 | M | F ||
Nom | der @'
check_eq " 5. options first, then the idiom bar"                '[M | F]'     '@zz :x 1 | M | F @'
check_eq " 6. options first, then an empty first element"       '[| M | F]'   '@zz :x 1 | | M | F @'

echo
echo "-- after a positional argument --"
check_eq " 7. the bar after the positional is the separator"    '[a][b | c]'  '@yy a | b | c @'
check_eq " 8. a second bar there is an empty first element"     '[a][| b | c]' '@yy a | | b | c @'

echo
echo "-- the middle and the end --"
check_eq " 9. an empty element between bars is kept"            '[M | | F]'   '@zz M | | F @'
check_eq "10. one trailing bar is trimmed"                      '[M | F]'     '@zz M | F | @'
check_eq "11. a row separator is never the stripped bar"        '[|| M | F]'  '@zz || M | F @'

echo
echo "================================"
echo "Passed: $PASS  Failed: $FAIL"
rm -f /tmp/rest_test_err.$$
[ $FAIL -eq 0 ]