#!/usr/bin/env bash
set -euo pipefail

REPO_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
SCRIPT="$REPO_ROOT/scripts/check-skill-version-bump.sh"
PASS=0
FAIL=0

pass() { echo "  PASS: $1"; PASS=$((PASS + 1)); }
fail() { echo "  FAIL: $1"; FAIL=$((FAIL + 1)); }

# The gate reads versions with python3 + PyYAML, the same hard requirement
# skill-size-check carries. Without them this suite cannot run: exit 77 so
# run-tests reports SKIPPED (and --strict fails the push).
if ! python3 -c 'import yaml' 2>/dev/null; then
  echo "SKIP: python3 with PyYAML is required" >&2
  exit 77
fi

# Output assertions use here-strings, never `echo | grep -q` (pipefail race;
# see docs/spec/gates.md, Tests).

CLEANUP_DIRS=()
trap 'rm -rf ${CLEANUP_DIRS[@]+"${CLEANUP_DIRS[@]}"}' EXIT

# write_skill <repo> <plugin> <skill> <version-line|""> [body]
# An empty version line writes a SKILL.md with no metadata block at all.
write_skill() {
  local repo="$1" plugin="$2" skill="$3" vline="$4" body="${5:-body}"
  local d="$repo/plugins/$plugin/.apm/skills/$skill"
  mkdir -p "$d"
  {
    echo "---"
    echo "name: $skill"
    echo "description: Use when testing."
    if [[ -n "$vline" ]]; then
      echo "metadata:"
      echo "  $vline"
    fi
    echo "---"
    echo "$body"
  } > "$d/SKILL.md"
}

commit() { (cd "$1" && git add -A && git commit -q -m "${2:-change}"); }

# A fixture with skills alpha (1.0.0) and beta (1.0.9) on main, then checked out
# onto a feature branch.
make_fixture() {
  local dir
  dir="$(mktemp -d)"
  CLEANUP_DIRS+=("$dir")
  (cd "$dir" && git init -q -b main && git config user.email t@t.t && git config user.name t)
  write_skill "$dir" demo alpha 'version: "1.0.0"'
  write_skill "$dir" demo beta "version: 1.0.9"
  commit "$dir" initial
  (cd "$dir" && git checkout -q -b feature)
  echo "$dir"
}

# Every PRE_COMMIT_* input comes from here: a value inherited from the pre-push
# hook running this suite names a sha of the real repo, not the fixture.
run_check() {
  local dir="$1"
  if [[ $# -ge 2 ]]; then
    (cd "$dir" && unset PRE_COMMIT_FROM_REF PRE_COMMIT_REMOTE_BRANCH \
      && PRE_COMMIT_TO_REF="$2" bash "$SCRIPT" 2>&1)
  else
    (cd "$dir" && unset PRE_COMMIT_FROM_REF PRE_COMMIT_TO_REF PRE_COMMIT_REMOTE_BRANCH \
      && bash "$SCRIPT" 2>&1)
  fi
}

# expect_pass <desc> <dir> [to-ref]
expect_pass() {
  local desc="$1"; shift
  local out
  if out="$(run_check "$@")" && [[ -z "$out" ]]; then
    pass "$desc"
  else
    fail "$desc — expected silent exit 0, got: $out"
  fi
}

# expect_fail <desc> <pattern> <dir> [to-ref]
expect_fail() {
  local desc="$1" pattern="$2"; shift 2
  local out
  if out="$(run_check "$@")"; then
    fail "$desc — expected non-zero exit, got 0"
  elif grep -qE "$pattern" <<< "$out"; then
    pass "$desc"
  else
    fail "$desc — output did not match /$pattern/: $out"
  fi
}

echo ""
echo "--- 1. unchanged skill passes ---"
F="$(make_fixture)"
echo "unrelated" > "$F/README.md"; commit "$F"
expect_pass "no skill change passes silently" "$F"

echo ""
echo "--- 2. changed without bump fails ---"
F="$(make_fixture)"
write_skill "$F" demo alpha 'version: "1.0.0"' "new body"; commit "$F"
expect_fail "unbumped change fails and names baseline and current" "alpha: 1\.0\.0 -> 1\.0\.0" "$F"

echo ""
echo "--- 3. changed with patch / minor / major bump passes ---"
for v in 1.0.1 1.1.0 2.0.0; do
  F="$(make_fixture)"
  write_skill "$F" demo alpha "version: \"$v\"" "new body"; commit "$F"
  expect_pass "bump to $v passes" "$F"
done

echo ""
echo "--- 4. version decreased fails ---"
F="$(make_fixture)"
write_skill "$F" demo beta "version: 1.0.8" "new body"; commit "$F"
expect_fail "decrease fails" "beta: 1\.0\.9 -> 1\.0\.8" "$F"

echo ""
echo "--- 5. change to a non-SKILL.md file still counts ---"
F="$(make_fixture)"
mkdir -p "$F/plugins/demo/.apm/skills/alpha/references"
echo "ref" > "$F/plugins/demo/.apm/skills/alpha/references/x.md"; commit "$F"
expect_fail "references/ change without bump fails" "alpha: 1\.0\.0 -> 1\.0\.0" "$F"

echo ""
echo "--- 6. tests/-only change passes without bump ---"
F="$(make_fixture)"
mkdir -p "$F/plugins/demo/.apm/skills/alpha/tests"
echo "t" > "$F/plugins/demo/.apm/skills/alpha/tests/test-x.sh"; commit "$F"
expect_pass "tests/-only change is exempt" "$F"

echo ""
echo "--- 7. new skill exempt ---"
F="$(make_fixture)"
write_skill "$F" demo gamma 'version: "0.1.0"'; commit "$F"
expect_pass "new skill passes" "$F"

echo ""
echo "--- 8. deleted skill exempt ---"
F="$(make_fixture)"
rm -rf "$F/plugins/demo/.apm/skills/alpha"; commit "$F"
expect_pass "deleted skill passes" "$F"

echo ""
echo "--- 9. renamed skill exempt ---"
F="$(make_fixture)"
(cd "$F" && git mv plugins/demo/.apm/skills/alpha plugins/demo/.apm/skills/alpha2)
commit "$F"
expect_pass "renamed skill passes (old absent at pushed, new absent at baseline)" "$F"

echo ""
echo "--- 10. missing version on changed skill fails ---"
F="$(make_fixture)"
write_skill "$F" demo alpha "" "new body"; commit "$F"
expect_fail "missing version fails" "alpha: metadata\.version missing" "$F"

echo ""
echo "--- 11. malformed / prerelease version fails ---"
for v in 'version: 1.1' 'version: "1.0.1-rc1"'; do
  F="$(make_fixture)"
  write_skill "$F" demo alpha "$v" "new body"; commit "$F"
  expect_fail "'$v' is rejected like skill-size-check rejects it" "alpha: metadata\.version missing or not" "$F"
done

echo ""
echo "--- 12. multiple offenders all reported ---"
F="$(make_fixture)"
write_skill "$F" demo alpha 'version: "1.0.0"' "x"
write_skill "$F" demo beta "version: 1.0.9" "x"
commit "$F"
OUT="$(run_check "$F" || true)"
if grep -q "alpha: 1.0.0 -> 1.0.0" <<< "$OUT" && grep -q "beta: 1.0.9 -> 1.0.9" <<< "$OUT" \
   && grep -q "bump PATCH at minimum" <<< "$OUT"; then
  pass "both offenders and the fix are reported"
else
  fail "not every offender reported: $OUT"
fi

echo ""
echo "--- 13. PRE_COMMIT_TO_REF respected over HEAD ---"
F="$(make_fixture)"
write_skill "$F" demo alpha 'version: "1.0.0"' "unbumped"; commit "$F"
BAD="$(cd "$F" && git rev-parse HEAD)"
(cd "$F" && git checkout -q -b clean main)
echo "unrelated" > "$F/README.md"; commit "$F"
CLEAN="$(cd "$F" && git rev-parse HEAD)"
expect_fail "unbumped TO_REF fails while HEAD is clean" "alpha: 1\.0\.0 -> 1\.0\.0" "$F" "$BAD"
(cd "$F" && git checkout -q "$BAD")
expect_pass "clean TO_REF passes while HEAD is unbumped" "$F" "$CLEAN"

echo ""
echo "--- 14. all-zeros delete sha no-ops ---"
F="$(make_fixture)"
write_skill "$F" demo alpha 'version: "1.0.0"' "unbumped"; commit "$F"
expect_pass "40-zero sha exits 0" "$F" "0000000000000000000000000000000000000000"
expect_pass "64-zero sha exits 0" "$F" "$(printf '0%.0s' {1..64})"

echo ""
echo "--- 15. bin plugin covered ---"
F="$(make_fixture)"
write_skill "$F" bin tool 'version: "1.0.0"'
(cd "$F" && git checkout -q main); commit "$F" "add bin skill"
(cd "$F" && git checkout -q feature && git merge -q main)
write_skill "$F" bin tool 'version: "1.0.0"' "changed"; commit "$F"
expect_fail "bin skill change without bump fails" "plugins/bin/\.apm/skills/tool: 1\.0\.0 -> 1\.0\.0" "$F"

echo ""
echo "--- 16. multi-digit semver compare ---"
F="$(make_fixture)"
write_skill "$F" demo beta "version: 1.0.10" "x"; commit "$F"
expect_pass "1.0.10 > 1.0.9 passes" "$F"

echo ""
echo "--- 17. pushed version must also exceed main's tip ---"
F="$(make_fixture)"
write_skill "$F" demo alpha 'version: "1.0.1"' "branch change"; commit "$F"
(cd "$F" && git checkout -q main)
write_skill "$F" demo alpha 'version: "1.0.5"' "main moved on"; commit "$F"
(cd "$F" && git checkout -q feature)
expect_fail "bump over the merge-base fails when main's tip is higher" \
  "alpha: 1\.0\.5 -> 1\.0\.1 \(not above main tip\)" "$F"
OUT="$(run_check "$F" || true)"
if grep -q "not above merge-base" <<< "$OUT"; then
  fail "merge-base reported as failed although 1.0.1 > 1.0.0: $OUT"
else
  pass "only the baseline actually failed is named"
fi
write_skill "$F" demo alpha 'version: "1.0.6"' "branch change 2"; commit "$F"
expect_pass "bump above both the merge-base and main's tip passes" "$F"

echo ""
echo "--- 18. origin/main preferred over local main ---"
F="$(make_fixture)"
write_skill "$F" demo alpha 'version: "1.0.1"' "x"; commit "$F"
# A stale local main pointing at the feature tip would make the diff empty;
# origin/main at the original commit must win and still see the change.
(cd "$F" && git update-ref refs/remotes/origin/main main && git branch -f main feature)
write_skill "$F" demo alpha 'version: "1.0.1"' "y"; commit "$F"
if OUT="$(run_check "$F")" && [[ -z "$OUT" ]]; then
  pass "origin/main used as baseline (1.0.0 -> 1.0.1 counted as a bump)"
else
  fail "unexpected output: $OUT"
fi
(cd "$F" && git update-ref refs/remotes/origin/main feature~1)
expect_fail "origin/main at the bumped commit flags the further unbumped change" \
  "merge-base with origin/main" "$F"
expect_fail "the report names alpha and the versions read from origin/main's merge-base" \
  "demo/\.apm/skills/alpha: 1\.0\.1 -> 1\.0\.1 \(not above merge-base\)" "$F"

echo ""
echo "--- 19. no main ref fails closed ---"
F="$(mktemp -d)"; CLEANUP_DIRS+=("$F")
(cd "$F" && git init -q -b trunk && git config user.email t@t.t && git config user.name t)
write_skill "$F" demo alpha 'version: "1.0.0"'; commit "$F"
expect_fail "missing main fails with a clear message" "neither origin/main nor main resolves" "$F"

echo ""
echo "--- 20. non-ASCII paths are not hidden by core.quotePath ---"
F="$(make_fixture)"
mkdir -p "$F/plugins/demo/.apm/skills/alpha/references"
echo "ref" > "$F/plugins/demo/.apm/skills/alpha/references/résumé.md"; commit "$F"
expect_fail "non-ASCII file under references/ without bump fails" "alpha: 1\.0\.0 -> 1\.0\.0" "$F"
F="$(make_fixture)"
(cd "$F" && git checkout -q main)
write_skill "$F" demo "café" 'version: "2.0.0"'; commit "$F" "add café"
(cd "$F" && git checkout -q feature && git merge -q main)
write_skill "$F" demo "café" 'version: "2.0.0"' "changed"; commit "$F"
expect_fail "non-ASCII skill dir without bump fails" "skills/café: 2\.0\.0 -> 2\.0\.0" "$F"
write_skill "$F" demo "café" 'version: "2.0.1"' "changed again"; commit "$F"
expect_pass "non-ASCII skill dir with bump passes" "$F"

echo ""
echo "--- 21. local main fallback: pushed commit already in main fails closed ---"
F="$(make_fixture)"
MAIN_SHA="$(cd "$F" && git rev-parse main)"
expect_fail "pushing main's sha without origin/main fails" \
  "origin/main does not resolve.*already contained in local main" "$F" "$MAIN_SHA"
(cd "$F" && git checkout -q main)
expect_fail "HEAD on main without origin/main fails" \
  "origin/main does not resolve and HEAD is already contained in local main" "$F"

echo ""
echo "--- 22. pushing main itself with origin/main present ---"
F="$(make_fixture)"
(cd "$F" && git checkout -q main && git update-ref refs/remotes/origin/main main)
expect_pass "main equal to origin/main passes (nothing changed vs main)" "$F"
write_skill "$F" demo alpha 'version: "1.0.1"' "x"; commit "$F"
expect_pass "main ahead of origin/main with a bump passes" "$F"
write_skill "$F" demo beta "version: 1.0.9" "x"; commit "$F"
expect_fail "main ahead of origin/main without a bump fails" "beta: 1\.0\.9 -> 1\.0\.9" "$F"
(cd "$F" && git update-ref refs/remotes/origin/main main)
expect_pass "already-merged content (merge-base == pushed) passes against origin/main" "$F" \
  "$(cd "$F" && git rev-parse main~1)"

echo ""
echo "--- 23. version shape is ASCII-only, bounded, and has no leading zeros ---"
for v in 'version: "１.0.1"' 'version: "1.0.１"' 'version: "1.0.9999999999"' \
         'version: "99999999999999999999.0.0"' 'version: "1.0.08"' 'version: "01.0.1"' \
         'version: "1.00.1"'; do
  F="$(make_fixture)"
  write_skill "$F" demo alpha "$v" "new body"; commit "$F"
  OUT="$(run_check "$F" || true)"
  if grep -q "alpha: metadata\.version missing or not" <<< "$OUT" \
     && ! grep -qiE "integer|syntax error|value too great" <<< "$OUT"; then
    pass "'$v' is rejected as invalid without a bash arithmetic error"
  else
    fail "'$v' not cleanly rejected: $OUT"
  fi
done
F="$(make_fixture)"
write_skill "$F" demo alpha 'version: "1.0.999999999"' "new body"; commit "$F"
expect_pass "nine-digit part is accepted and compared" "$F"
F="$(make_fixture)"
write_skill "$F" demo alpha 'version: "1.0.10"' "new body"; commit "$F"
expect_pass "a zero inside a part (1.0.10) is not a leading zero" "$F"

echo ""
echo "--- 24. python3 / PyYAML failures are never reported as a missing version ---"
REAL_PYTHON="$(command -v python3)"
SHIM_ROOT="$(mktemp -d)"; CLEANUP_DIRS+=("$SHIM_ROOT")
mkdir -p "$SHIM_ROOT/shadow" "$SHIM_ROOT/noyaml" "$SHIM_ROOT/crash"
printf 'raise ImportError("PyYAML deliberately unavailable in this fixture")\n' \
  > "$SHIM_ROOT/shadow/yaml.py"
cat > "$SHIM_ROOT/noyaml/python3" <<EOF
#!/bin/sh
PYTHONPATH="$SHIM_ROOT/shadow\${PYTHONPATH:+:\$PYTHONPATH}" exec "$REAL_PYTHON" "\$@"
EOF
# Passes the up-front import probe, crashes on the real read.
cat > "$SHIM_ROOT/crash/python3" <<EOF
#!/bin/sh
[ "\$1" = "-c" ] && [ "\$2" = "import yaml" ] && exec "$REAL_PYTHON" "\$@"
echo "Traceback: simulated interpreter failure" >&2
exit 1
EOF
chmod +x "$SHIM_ROOT/noyaml/python3" "$SHIM_ROOT/crash/python3"
if PATH="$SHIM_ROOT/noyaml:$PATH" python3 -c 'import yaml' 2>/dev/null; then
  fail "fixture check: the no-PyYAML shim still imports yaml — the next assertion would be vacuous"
else
  pass "fixture check: the no-PyYAML shim makes 'import yaml' fail"
fi
F="$(make_fixture)"
write_skill "$F" demo alpha 'version: "1.0.1"' "new body"; commit "$F"
OUT="$(cd "$F" && unset PRE_COMMIT_FROM_REF PRE_COMMIT_TO_REF PRE_COMMIT_REMOTE_BRANCH \
  && PATH="$SHIM_ROOT/noyaml:$PATH" bash "$SCRIPT" 2>&1)" && RC=0 || RC=$?
if [[ $RC -ne 0 ]] && grep -q "PyYAML is required" <<< "$OUT" && grep -q "Fix: python3 -m pip install PyYAML" <<< "$OUT" \
   && ! grep -q "Traceback" <<< "$OUT"; then
  pass "missing PyYAML fails with FAIL + Fix, no traceback"
else
  fail "missing PyYAML not reported cleanly (rc=$RC): $OUT"
fi
OUT="$(cd "$F" && unset PRE_COMMIT_FROM_REF PRE_COMMIT_TO_REF PRE_COMMIT_REMOTE_BRANCH \
  && PATH="$SHIM_ROOT/crash:$PATH" bash "$SCRIPT" 2>&1)" && RC=0 || RC=$?
if [[ $RC -ne 0 ]] && grep -q "could not read metadata.version" <<< "$OUT" \
   && ! grep -q "missing or not" <<< "$OUT"; then
  pass "python3 crash during the read is a read failure, not a missing version"
else
  fail "python3 crash misreported (rc=$RC): $OUT"
fi

echo ""
echo "--- 25. SKILL.md deleted but skill dir kept ---"
F="$(make_fixture)"
mkdir -p "$F/plugins/demo/.apm/skills/alpha/references"
echo "ref" > "$F/plugins/demo/.apm/skills/alpha/references/x.md"
rm "$F/plugins/demo/.apm/skills/alpha/SKILL.md"; commit "$F"
expect_fail "missing SKILL.md is reported as such" "alpha: SKILL\.md missing at HEAD \(baseline: 1\.0\.0\)" "$F"

echo ""
echo "--- 26. baseline without a valid version accepts any valid version ---"
F="$(make_fixture)"
(cd "$F" && git checkout -q main)
write_skill "$F" demo legacy ""; commit "$F" "add legacy skill"
(cd "$F" && git checkout -q feature && git merge -q main)
write_skill "$F" demo legacy 'version: "0.0.1"' "changed"; commit "$F"
expect_pass "invalid baseline + valid current passes" "$F"

echo ""
echo "--- 27. no merge-base (unrelated histories) fails closed ---"
F="$(make_fixture)"
(cd "$F" && git checkout -q --orphan unrelated && git rm -rq --cached . && rm -rf plugins)
write_skill "$F" demo alpha 'version: "1.0.0"' "orphan"; commit "$F" "orphan root"
expect_fail "unrelated history fails at the merge-base check" "no merge-base between main and HEAD" "$F"

echo ""
echo "--- 28. annotated tag objects as PRE_COMMIT_TO_REF ---"
F="$(make_fixture)"
write_skill "$F" demo alpha 'version: "1.0.0"' "unbumped"; commit "$F"
(cd "$F" && git tag -a v9 -m "tag" && git checkout -q main)
TAG_OBJ="$(cd "$F" && git rev-parse v9)"
if [[ "$(cd "$F" && git cat-file -t "$TAG_OBJ")" == "tag" ]]; then
  pass "fixture check: TO_REF is a tag object, not a commit"
else
  fail "fixture check: v9 is not an annotated tag object"
fi
expect_fail "unbumped change behind an annotated tag fails" "alpha: 1\.0\.0 -> 1\.0\.0" "$F" "$TAG_OBJ"
# Peeling is what makes the local-main fallback's "pushed commit is the
# merge-base" test see through a tag: compared unpeeled, the tag's own sha
# never equals the merge-base and the empty diff would pass.
(cd "$F" && git tag -a on-main -m "tag" main)
expect_fail "a tag on local main's commit fails closed like the commit itself" \
  "origin/main does not resolve and [0-9a-f]+ is already contained in local main" \
  "$F" "$(cd "$F" && git rev-parse on-main)"
(cd "$F" && git tag -a tree-tag -m "tag" "main^{tree}")
expect_fail "a tag on a tree fails closed" "pushed ref [0-9a-f]+ does not resolve to a commit" \
  "$F" "$(cd "$F" && git rev-parse tree-tag)"

echo ""
echo "--- 29. CRLF frontmatter is parsed ---"
# crlf <repo> <skill>: rewrite that skill's SKILL.md with CRLF line endings.
crlf() {
  local f="$1/plugins/demo/.apm/skills/$2/SKILL.md"
  sed 's/$/\r/' "$f" > "$f.tmp" && mv "$f.tmp" "$f"
}
F="$(make_fixture)"
(cd "$F" && git config core.autocrlf false && git checkout -q main)
crlf "$F" alpha; commit "$F" "alpha to CRLF"
(cd "$F" && git checkout -q feature && git merge -q main)
write_skill "$F" demo alpha 'version: "1.0.0"' "crlf body"; crlf "$F" alpha; commit "$F"
if grep -q $'\r' "$F/plugins/demo/.apm/skills/alpha/SKILL.md"; then
  pass "fixture check: SKILL.md carries CRLF"
else
  fail "fixture check: SKILL.md has no CRLF"
fi
expect_fail "unbumped CRLF skill reports both parsed versions" "alpha: 1\.0\.0 -> 1\.0\.0" "$F"
write_skill "$F" demo alpha 'version: "1.0.1"' "crlf body 2"; crlf "$F" alpha; commit "$F"
expect_pass "bumped CRLF skill passes" "$F"

echo ""
echo "--- 30. identical bump already merged to main fails ---"
# Branches A and B both bump alpha 1.0.0 -> 1.0.1 with different content. The
# bumps do not conflict at merge, so without the tip rule main would ship two
# changes under one version.
F="$(make_fixture)"
(cd "$F" && git checkout -q -b branch-a main)
write_skill "$F" demo alpha 'version: "1.0.1"' "change A"; commit "$F"
(cd "$F" && git checkout -q main && git merge -q --no-ff -m "merge A" branch-a \
  && git update-ref refs/remotes/origin/main main && git checkout -q feature)
write_skill "$F" demo alpha 'version: "1.0.1"' "change B"; commit "$F"
expect_fail "B's 1.0.1 fails against A's 1.0.1 on origin/main" \
  "alpha: 1\.0\.1 -> 1\.0\.1 \(not above origin/main tip\)" "$F"
write_skill "$F" demo alpha 'version: "1.0.2"' "change B 2"; commit "$F"
expect_pass "B at 1.0.2 passes" "$F"

echo ""
echo "--- 31. skill deleted on main's tip: only the merge-base rule applies ---"
F="$(make_fixture)"
(cd "$F" && git checkout -q main)
rm -rf "$F/plugins/demo/.apm/skills/alpha"; commit "$F" "drop alpha on main"
(cd "$F" && git checkout -q feature)
write_skill "$F" demo alpha 'version: "1.0.1"' "branch change"; commit "$F"
expect_pass "bump over the merge-base passes when main's tip lacks the skill" "$F"
(cd "$F" && git checkout -q -b unbumped main~1)
write_skill "$F" demo alpha 'version: "1.0.0"' "unbumped"; commit "$F"
expect_fail "unbumped change still fails against the merge-base" \
  "alpha: 1\.0\.0 -> 1\.0\.0 \(not above merge-base\)" "$F"

echo ""
echo "--- 32. UTF-8 BOM before the frontmatter is parsed ---"
# bom <repo> <skill>: prefix that skill's SKILL.md with a UTF-8 byte-order mark.
bom() {
  local f="$1/plugins/demo/.apm/skills/$2/SKILL.md"
  { printf '\xef\xbb\xbf'; cat "$f"; } > "$f.tmp" && mv "$f.tmp" "$f"
}
F="$(make_fixture)"
write_skill "$F" demo alpha 'version: "1.0.0"' "bom body"; bom "$F" alpha; commit "$F"
if [[ "$(head -c 3 "$F/plugins/demo/.apm/skills/alpha/SKILL.md" | od -An -tx1 | tr -d ' ')" == "efbbbf" ]]; then
  pass "fixture check: SKILL.md starts with a BOM"
else
  fail "fixture check: SKILL.md has no BOM"
fi
expect_fail "unbumped BOM skill reports its parsed version, not a missing one" \
  "alpha: 1\.0\.0 -> 1\.0\.0 \(not above merge-base\)" "$F"
write_skill "$F" demo alpha 'version: "1.0.1"' "bom body 2"; bom "$F" alpha; commit "$F"
expect_pass "bumped BOM skill passes" "$F"

echo ""
echo "--- 33. a file moved from one skill to another flags both ---"
# --no-renames: with rename detection, --name-only lists only the new path and
# alpha would lose a file without anyone noticing.
F="$(make_fixture)"
(cd "$F" && git checkout -q main)
mkdir -p "$F/plugins/demo/.apm/skills/alpha/references"
printf 'ref line %s\n' 1 2 3 4 5 > "$F/plugins/demo/.apm/skills/alpha/references/x.md"
commit "$F" "alpha reference"
(cd "$F" && git checkout -q feature && git merge -q main)
mkdir -p "$F/plugins/demo/.apm/skills/beta/references"
(cd "$F" && git mv plugins/demo/.apm/skills/alpha/references/x.md plugins/demo/.apm/skills/beta/references/x.md)
write_skill "$F" demo beta "version: 1.0.10"; commit "$F"
expect_fail "alpha is flagged although only beta was bumped" \
  "alpha: 1\.0\.0 -> 1\.0\.0 \(not above merge-base\)" "$F"

echo ""
echo "--- 34. comparison is ordered major first ---"
F="$(make_fixture)"
(cd "$F" && git checkout -q main)
write_skill "$F" demo alpha 'version: "2.0.0"'; commit "$F" "alpha 2.0.0"
(cd "$F" && git checkout -q feature && git merge -q main)
write_skill "$F" demo alpha 'version: "1.9.0"' "new body"; commit "$F"
expect_fail "2.0.0 -> 1.9.0 fails although minor rose" "alpha: 2\.0\.0 -> 1\.9\.0" "$F"

echo ""
echo "--- 35. unresolvable PRE_COMMIT_TO_REF fails closed ---"
F="$(make_fixture)"
expect_fail "a sha absent from the repo fails" \
  "pushed ref 1234567890abcdef1234567890abcdef12345678 does not resolve to a commit" \
  "$F" "1234567890abcdef1234567890abcdef12345678"

echo ""
echo "--- 36. a SKILL.md git cannot read fails closed ---"
# drop_blob <repo> <rev:path>: delete that blob's loose object, as a corrupt or
# partial clone would lack it. The tree still names the file.
drop_blob() {
  local sha
  sha="$(cd "$1" && git rev-parse "$2")"
  rm -f "$1/.git/objects/${sha:0:2}/${sha:2}"
}
F="$(make_fixture)"
write_skill "$F" demo alpha 'version: "1.0.1"' "new body"; commit "$F"
drop_blob "$F" "HEAD:plugins/demo/.apm/skills/alpha/SKILL.md"
OUT="$(run_check "$F")" && RC=0 || RC=$?
if [[ $RC -ne 0 ]] && grep -q "could not read metadata.version from [0-9a-f]*:plugins/demo/.apm/skills/alpha/SKILL.md" <<< "$OUT" \
   && grep -q "fatal: bad object" <<< "$OUT" && ! grep -qE "missing or not|SKILL\.md missing" <<< "$OUT"; then
  pass "an unreadable pushed SKILL.md is a read failure carrying git's error"
else
  fail "unreadable pushed SKILL.md misreported (rc=$RC): $OUT"
fi
F="$(make_fixture)"
write_skill "$F" demo alpha 'version: "1.0.1"' "new body"; commit "$F"
drop_blob "$F" "main:plugins/demo/.apm/skills/alpha/SKILL.md"
OUT="$(run_check "$F")" && RC=0 || RC=$?
if [[ $RC -ne 0 ]] && grep -q "could not read metadata.version" <<< "$OUT"; then
  pass "an unreadable merge-base SKILL.md fails closed instead of exempting the skill"
else
  fail "unreadable merge-base SKILL.md not caught (rc=$RC): $OUT"
fi

echo ""
echo "--- 37. a mode-only change counts as a change ---"
F="$(make_fixture)"
(cd "$F" && git config core.fileMode true)
chmod +x "$F/plugins/demo/.apm/skills/alpha/SKILL.md"; commit "$F"
if [[ "$(cd "$F" && git diff --summary main HEAD)" == *"mode change 100644 => 100755"* ]]; then
  pass "fixture check: the commit changes only the file mode"
else
  fail "fixture check: no mode change recorded"
fi
expect_fail "chmod +x without a bump fails" "alpha: 1\.0\.0 -> 1\.0\.0" "$F"

echo ""
echo "--- 38. skill directory replaced by a symlink ---"
# Current behaviour, pinned: the path is no longer a tree at the pushed commit,
# so the skill is exempt as deleted. apm drops symlinks under .apm/ (ADR-0017),
# so readers do lose the skill.
F="$(make_fixture)"
rm -rf "$F/plugins/demo/.apm/skills/alpha"
ln -s beta "$F/plugins/demo/.apm/skills/alpha"; commit "$F"
if [[ "$(cd "$F" && git ls-tree HEAD plugins/demo/.apm/skills/alpha)" == 120000* ]]; then
  pass "fixture check: alpha is committed as a symlink"
else
  fail "fixture check: alpha is not a symlink in the commit"
fi
expect_pass "a skill replaced by a symlink is exempt as deleted" "$F"

echo ""
echo "--- 39. leading blank lines before the frontmatter are parsed ---"
# skill-size-check's FRONTMATTER_RE accepts whitespace before the opening
# `---`; this gate must read the same shape. Otherwise the pushed side reports
# "missing" for a file the commit hook accepted, and a baseline shaped this way
# reads as "no valid version", which lets any version pass.
# blank_lead <repo> <skill>: prefix that skill's SKILL.md with blank lines.
blank_lead() {
  local f="$1/plugins/demo/.apm/skills/$2/SKILL.md"
  { printf '\n \t\n'; cat "$f"; } > "$f.tmp" && mv "$f.tmp" "$f"
}
F="$(make_fixture)"
(cd "$F" && git checkout -q main)
blank_lead "$F" alpha; commit "$F" "alpha leading blank"
(cd "$F" && git checkout -q feature && git merge -q main)
write_skill "$F" demo alpha 'version: "1.0.0"' "lead body"; blank_lead "$F" alpha; commit "$F"
expect_fail "unbumped skill with leading blank lines is held to its baseline version" \
  "alpha: 1\.0\.0 -> 1\.0\.0 \(not above merge-base\)" "$F"
write_skill "$F" demo alpha 'version: "1.0.1"' "lead body 2"; blank_lead "$F" alpha; commit "$F"
expect_pass "bumped skill with leading blank lines passes" "$F"

echo ""
echo "Results: $PASS passed, $FAIL failed"
[[ $FAIL -eq 0 ]]