#!/bin/sh
# Tests for bin/generate-index.
#
# SKILLS_INDEX.md was maintained by hand and drifted: two skills shipped with
# no row at all (#15), because their rows lived on branches squash-merged after
# a directory reorg. A gate caught drift after the fact; generating the table
# from frontmatter removes the class entirely (#29) — the curated summary and
# trigger now live next to the skill they describe, which is the same argument
# that made a hand-maintained index the wrong shape.

set -u

ROOT=$(CDPATH= cd -- "$(dirname -- "$0")/.." && pwd)
SUT="$ROOT/bin/generate-index"

pass=0
fail=0
WORK=${TMPDIR:-/tmp}/generate_index_test.$$

if [ ! -f "$SUT" ]; then
  printf 'FAIL: %s does not exist\n' "$SUT"
  exit 1
fi

cleanup() { rm -rf "$WORK"; }
trap cleanup EXIT INT TERM

ok() { pass=$((pass + 1)); printf '  ok   %s\n' "$1"; }
no() { fail=$((fail + 1)); printf '  FAIL %s\n%s\n' "$1" "${2:-}"; }

# skill <root> <name> <surfaces> [summary] [use_when]
skill() {
  mkdir -p "$1/skills/$2"
  {
    printf -- '---\nname: %s\nsurfaces: %s\n' "$2" "$3"
    [ $# -lt 4 ] || printf 'summary: "%s"\n' "$4"
    [ $# -lt 5 ] || printf 'use_when: "%s"\n' "$5"
    printf -- 'description: d\n---\n'
  } > "$1/skills/$2/SKILL.md"
}

# fixture <name> — a root with an index carrying the generated-table markers.
fixture() {
  _f="$WORK/$1"
  mkdir -p "$_f"
  cat > "$_f/SKILLS_INDEX.md" <<'IDX'
# Engineering Skills Index

<!-- BEGIN skills-table -->
<!-- END skills-table -->

## Wiring
prose that must survive regeneration
IDX
  printf '%s' "$_f"
}

f=$(fixture basic)
skill "$f" beta '[claude-code, library]' 'B summary' 'when B'
skill "$f" alpha '[chat]' 'A summary' 'when A'
out=$(sh "$SUT" "$f" 2>&1); rc=$?
if [ "$rc" -ne 0 ]; then
  no 'generates a table' "$out"
elif ! grep -q '^| `alpha` | A summary | when A |' "$f/SKILLS_INDEX.md"; then
  no 'generates a table' "$(cat "$f/SKILLS_INDEX.md")"
elif ! grep -q 'prose that must survive regeneration' "$f/SKILLS_INDEX.md"; then
  no 'content outside the markers survives' "$(cat "$f/SKILLS_INDEX.md")"
elif [ "$(grep -n '`alpha`' "$f/SKILLS_INDEX.md" | cut -d: -f1)" -gt "$(grep -n '`beta`' "$f/SKILLS_INDEX.md" | cut -d: -f1)" ]; then
  no 'rows are sorted' "$(cat "$f/SKILLS_INDEX.md")"
else
  ok 'generates a sorted table and leaves the rest of the file alone'
fi

# The surfaces a skill ships to are the point of #29, so they are visible.
grep -q 'chat' "$f/SKILLS_INDEX.md" \
  && ok 'the row names the surfaces' \
  || no 'the row names the surfaces' "$(cat "$f/SKILLS_INDEX.md")"

# Idempotent: a second run changes nothing.
before=$(cat "$f/SKILLS_INDEX.md")
sh "$SUT" "$f" >/dev/null 2>&1
[ "$before" = "$(cat "$f/SKILLS_INDEX.md")" ] \
  && ok 'regeneration is idempotent' \
  || no 'regeneration is idempotent'

# --check is the CI gate: clean tree passes.
sh "$SUT" --check "$f" >/dev/null 2>&1 \
  && ok '--check passes on a generated index' \
  || no '--check passes on a generated index'

# ...and fails once a skill appears without regenerating.
skill "$f" gamma '[library]' 'G summary' 'when G'
if sh "$SUT" --check "$f" >/dev/null 2>&1; then
  no '--check fails on a stale index'
else
  ok '--check fails on a stale index'
fi

# A skill with no curated summary is an error, not an empty cell: the table
# cell is what a reader scans, and a blank one is worse than a missing row.
f=$(fixture nosummary)
skill "$f" alpha '[library]'
out=$(sh "$SUT" "$f" 2>&1); rc=$?
if [ "$rc" -eq 0 ]; then
  no 'a missing summary is an error' "$out"
elif ! printf '%s' "$out" | grep -q alpha; then
  no 'a missing summary is an error' "$out"
else
  ok 'a missing summary is an error naming the skill'
fi

printf '\ngenerate_index: %d passed, %d failed\n' "$pass" "$fail"
[ "$fail" -eq 0 ]