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

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

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

# Helper: write a minimal .pre-commit-hooks.yaml exposing one script entry and
# one --config-bearing entry, so RELEASE_PATHS (derived from the manifest, not
# hand-maintained) has both shapes to parse.
write_manifest() {
  local dir="$1"
  mkdir -p "$dir/vale"
  cat > "$dir/.pre-commit-hooks.yaml" <<'EOF'
-   id: fake-size-check
    entry: scripts/skill-size-check.sh
    language: script
-   id: fake-vale-check
    entry: scripts/vale-wrap.sh --config vale/.vale.ini
    language: script
EOF
}

# Helper: a fixture repo with a manifest and its two referenced release-relevant
# paths, committed and tagged v1.0.0.
make_tagged_fixture() {
  local dir
  dir="$(mktemp -d)"
  (cd "$dir" && git init -q && git config user.email t@t.t && git config user.name t)
  write_manifest "$dir"
  mkdir -p "$dir/scripts"
  echo "v1" > "$dir/scripts/skill-size-check.sh"
  echo "cfg" > "$dir/vale/.vale.ini"
  (cd "$dir" && git add -A && git commit -q -m "initial" && git tag v1.0.0)
  echo "$dir"
}

run_check() {
  local dir="$1" branch="$2"
  (cd "$dir" && PRE_COMMIT_REMOTE_BRANCH="$branch" bash "$SCRIPT" 2>&1)
}

CLEANUP_DIRS=()
trap 'rm -rf "${CLEANUP_DIRS[@]}"' EXIT
track() { CLEANUP_DIRS+=("$1"); }

# --- 1. Not targeting main: silent no-op regardless of state ---
echo ""
echo "--- exits 0 when not pushing to main, even with no tags ---"
FIXTURE1="$(mktemp -d)"; track "$FIXTURE1"
(cd "$FIXTURE1" && git init -q)
if run_check "$FIXTURE1" "refs/heads/feature-branch" > /dev/null; then
  pass "exits 0 when target branch isn't main"
else
  fail "exited non-zero on a non-main target branch"
fi

# --- 2. Targeting main, no tag exists at all: hard fail ---
echo ""
echo "--- exits 1 when targeting main and no tag exists ---"
FIXTURE2="$(mktemp -d)"; track "$FIXTURE2"
(cd "$FIXTURE2" && git init -q && git config user.email t@t.t && git config user.name t)
write_manifest "$FIXTURE2"
mkdir -p "$FIXTURE2/scripts"
echo "v1" > "$FIXTURE2/scripts/skill-size-check.sh"
echo "cfg" > "$FIXTURE2/vale/.vale.ini"
(cd "$FIXTURE2" && git add -A && git commit -q -m "initial")
if run_check "$FIXTURE2" "refs/heads/main" > /dev/null; then
  fail "exited 0 when targeting main with no tag — expected exit 1"
else
  pass "exits non-zero when targeting main and no tag exists yet"
fi

# --- 3. Targeting main, tag exists, no release-relevant changes since: passes ---
echo ""
echo "--- exits 0 when targeting main and nothing release-relevant changed since the tag ---"
FIXTURE3="$(make_tagged_fixture)"; track "$FIXTURE3"
echo "unrelated" > "$FIXTURE3/README.md"
(cd "$FIXTURE3" && git add -A && git commit -q -m "unrelated change")
if run_check "$FIXTURE3" "refs/heads/main" > /dev/null; then
  pass "exits 0 when only unrelated files changed since the tag"
else
  fail "exited non-zero despite no release-relevant changes since the tag"
fi

# --- 4. Targeting main, tag exists, a release-relevant file changed since: hard fail ---
echo ""
echo "--- exits 1 when a release-relevant file changed since the tag ---"
FIXTURE4="$(make_tagged_fixture)"; track "$FIXTURE4"
echo "v2" > "$FIXTURE4/scripts/skill-size-check.sh"
(cd "$FIXTURE4" && git add -A && git commit -q -m "update release-relevant script")
OUT4=$(run_check "$FIXTURE4" "refs/heads/main" || true)
if echo "$OUT4" | grep -q "skill-size-check.sh"; then
  pass "exits non-zero and names the changed file when a release-relevant path changed since the tag"
else
  fail "did not flag the release-relevant file that changed since the tag"
fi

# --- 5. Not targeting main even with release-relevant changes and a tag: still a no-op ---
echo ""
echo "--- exits 0 on a feature branch even with release-relevant changes since the tag ---"
FIXTURE5="$(make_tagged_fixture)"; track "$FIXTURE5"
echo "v2" > "$FIXTURE5/scripts/skill-size-check.sh"
(cd "$FIXTURE5" && git add -A && git commit -q -m "update release-relevant script")
if run_check "$FIXTURE5" "refs/heads/some-feature" > /dev/null; then
  pass "exits 0 on a feature branch regardless of un-tagged release-relevant changes"
else
  fail "hard-failed on a feature branch — should only ever fail when targeting main"
fi

# --- 6. A release-relevant path deleted since the tag is still flagged ---
echo ""
echo "--- exits 1 when a release-relevant path was deleted since the tag, not just modified ---"
FIXTURE6="$(make_tagged_fixture)"; track "$FIXTURE6"
rm -rf "$FIXTURE6/vale"
(cd "$FIXTURE6" && git add -A && git commit -q -m "delete the vale config dir")
OUT6=$(run_check "$FIXTURE6" "refs/heads/main" || true)
if echo "$OUT6" | grep -q "vale/.vale.ini"; then
  pass "flags a deleted release-relevant path instead of silently dropping it from the diff"
else
  fail "did not flag deletion of a release-relevant path since the tag"
fi

# --- 7. A git diff failure hard-fails instead of reading as a clean pass ---
echo ""
echo "--- exits 1 (not a silent pass) when the underlying git diff errors out ---"
FIXTURE7="$(make_tagged_fixture)"; track "$FIXTURE7"
TAG_TREE="$(cd "$FIXTURE7" && git rev-parse 'v1.0.0^{tree}')"
echo "v2" > "$FIXTURE7/scripts/skill-size-check.sh"
(cd "$FIXTURE7" && git add -A && git commit -q -m "advance past the tag")
rm -f "$FIXTURE7/.git/objects/${TAG_TREE:0:2}/${TAG_TREE:2}"
if run_check "$FIXTURE7" "refs/heads/main" > /dev/null; then
  fail "silently exited 0 when the underlying git diff failed"
else
  pass "hard-fails instead of silently passing when git diff can't be computed"
fi

# --- 8. A non-version tag reachable from HEAD does not become the diff baseline ---
echo ""
echo "--- ignores a non-vX.Y.Z tag and still flags a change since the real release tag ---"
FIXTURE8="$(make_tagged_fixture)"; track "$FIXTURE8"
echo "checkpoint" > "$FIXTURE8/scripts/skill-size-check.sh"
(cd "$FIXTURE8" && git add -A && git commit -q -m "checkpoint work" && git tag checkpoint-1)
echo "v2" > "$FIXTURE8/scripts/skill-size-check.sh"
(cd "$FIXTURE8" && git add -A && git commit -q -m "real release-relevant change")
OUT8=$(run_check "$FIXTURE8" "refs/heads/main" || true)
if echo "$OUT8" | grep -q "skill-size-check.sh"; then
  pass "still flags the release-relevant change since v1.0.0, ignoring the non-version checkpoint tag"
else
  fail "an incidental non-version tag shifted the baseline and hid a real release-relevant change"
fi

# --- 9. A file outside every manifest entry does not trigger a fail ---
echo ""
echo "--- exits 0 when a changed file sits near, but isn't referenced by, a manifest entry ---"
FIXTURE9="$(make_tagged_fixture)"; track "$FIXTURE9"
echo "irrelevant" > "$FIXTURE9/scripts/unrelated-helper.sh"
(cd "$FIXTURE9" && git add -A && git commit -q -m "add an unrelated script alongside the exposed one")
if run_check "$FIXTURE9" "refs/heads/main" > /dev/null; then
  pass "exits 0 for a file that lives alongside, but isn't referenced by, any manifest entry"
else
  fail "flagged a file that no .pre-commit-hooks.yaml entry actually exposes"
fi

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