#!/usr/bin/env bash
# Verify a downloaded MoonBite release artifact.
#
#   scripts/release/verify-release.sh <artifact> [SHA256SUMS.txt] [--pub deploy/moonbite-release.pub] [--owner moonbitecoin]
#
# Checks, in order:
#   1. sha256   - the artifact's hash appears in SHA256SUMS.txt under its own name   (REQUIRED)
#   2. minisign - SHA256SUMS.txt.minisig verifies against the pinned public key      (when minisign is installed and the key is not the placeholder)
#   3. sigstore - `gh attestation verify <artifact> --owner <owner>` passes          (when gh is installed)
#
# Exit 0 only when every check that could run passed. A check that could not run
# (tool missing, placeholder key, no .minisig) is reported as SKIP and does not
# fail the result, but the summary says what was and was not proven.
# Works in bash on Linux, macOS and Git Bash. No emoji; plain PASS/FAIL/SKIP.
set -euo pipefail

usage() { sed -n '2,15p' "$0" | sed 's/^# \{0,1\}//'; exit 2; }

ARTIFACT=""; SUMS=""; PUB=""; OWNER="moonbitecoin"
while [ $# -gt 0 ]; do
  case "$1" in
    --pub)   PUB="$2"; shift 2 ;;
    --owner) OWNER="$2"; shift 2 ;;
    -h|--help) usage ;;
    -*) echo "unknown option: $1"; usage ;;
    *) if [ -z "$ARTIFACT" ]; then ARTIFACT="$1"; elif [ -z "$SUMS" ]; then SUMS="$1"; else usage; fi; shift ;;
  esac
done
[ -n "$ARTIFACT" ] || usage
[ -f "$ARTIFACT" ] || { echo "FAIL  artifact not found: $ARTIFACT"; exit 1; }

DIR="$(cd "$(dirname "$ARTIFACT")" && pwd)"
NAME="$(basename "$ARTIFACT")"
[ -n "$SUMS" ] || SUMS="$DIR/SHA256SUMS.txt"
if [ -z "$PUB" ]; then
  HERE="$(cd "$(dirname "$0")" && pwd)"
  for c in "$DIR/moonbite-release.pub" "$HERE/../../deploy/moonbite-release.pub"; do
    [ -f "$c" ] && { PUB="$c"; break; }
  done
fi

pass=0; fail=0; skip=0
ok()   { echo "PASS  $*"; pass=$((pass+1)); }
bad()  { echo "FAIL  $*"; fail=$((fail+1)); }
skp()  { echo "SKIP  $*"; skip=$((skip+1)); }

sha256_of() {
  if command -v sha256sum >/dev/null 2>&1; then sha256sum "$1" | cut -d' ' -f1
  elif command -v shasum >/dev/null 2>&1; then shasum -a 256 "$1" | cut -d' ' -f1
  else openssl dgst -sha256 "$1" | awk '{print $NF}'; fi
}

echo "artifact : $ARTIFACT"
echo "manifest : $SUMS"
echo "pubkey   : ${PUB:-<none found>}"
echo

# 1. sha256 ------------------------------------------------------------------
if [ ! -f "$SUMS" ]; then
  bad "sha256: manifest not found ($SUMS). Download SHA256SUMS.txt from the same release."
else
  ACTUAL="$(sha256_of "$ARTIFACT" | tr 'A-F' 'a-f')"
  # "<hex>  name" or "<hex> *name"; match on basename
  EXPECTED="$(grep -Ei "^[0-9a-f]{64}[[:space:]]+\*?(.*/)?${NAME//./\\.}[[:space:]]*$" "$SUMS" | head -1 | awk '{print tolower($1)}' || true)"
  if [ -z "$EXPECTED" ]; then
    bad "sha256: '$NAME' is not listed in $SUMS"
  elif [ "$EXPECTED" = "$ACTUAL" ]; then
    ok "sha256: $ACTUAL matches manifest"
  else
    bad "sha256: MISMATCH  manifest=$EXPECTED  actual=$ACTUAL  -- do not run this file"
  fi
fi

# 2. minisign ------------------------------------------------------------------
KEYLINE=""
if [ -n "$PUB" ] && [ -f "$PUB" ]; then
  KEYLINE="$(grep -v '^[[:space:]]*#' "$PUB" | grep -v '^[[:space:]]*$' | grep -v '^untrusted comment' | head -1 || true)"
fi
if ! command -v minisign >/dev/null 2>&1; then
  skp "minisign: tool not installed (https://jedisct1.github.io/minisign/)"
elif [ -z "$KEYLINE" ] || [ "${KEYLINE#REPLACE_ME}" != "$KEYLINE" ]; then
  skp "minisign: release public key is still a placeholder (key ceremony pending, deploy/RELEASE-SIGNING.md)"
elif [ ! -f "$SUMS.minisig" ]; then
  skp "minisign: no $(basename "$SUMS").minisig next to the manifest"
elif minisign -Vm "$SUMS" -P "$KEYLINE" >/dev/null 2>&1; then
  ok "minisign: $(basename "$SUMS").minisig verifies against pinned key"
else
  bad "minisign: signature on $(basename "$SUMS") does NOT verify -- manifest may be forged"
fi

# 3. Sigstore attestation ------------------------------------------------------
if ! command -v gh >/dev/null 2>&1; then
  skp "sigstore: GitHub CLI (gh) not installed; cannot check build provenance"
else
  if OUT="$(gh attestation verify "$ARTIFACT" --owner "$OWNER" 2>&1)"; then
    ok "sigstore: attestation verified for owner '$OWNER' (built by GitHub Actions from the public repo)"
    echo "$OUT" | grep -Ei 'repo|workflow|ref' | sed 's/^/        /' || true
  else
    case "$OUT" in
      *"not logged"*|*"auth login"*|*"authentication"*|*"Bad credentials"*|*"HTTP 401"*)
        skp "sigstore: gh is not authenticated or its token is invalid (run 'gh auth login'); attestation not checked" ;;
      *)
        bad "sigstore: no valid attestation for this file under owner '$OWNER'"
        echo "$OUT" | tail -5 | sed 's/^/        /' ;;
    esac
  fi
fi

# Summary ----------------------------------------------------------------------
echo
echo "result: $pass passed, $fail failed, $skip skipped"
if [ "$fail" -gt 0 ]; then
  echo "VERDICT: FAIL - do not use this artifact."
  exit 1
fi
if [ "$pass" -eq 0 ]; then
  echo "VERDICT: NOTHING PROVEN - no check could run."
  exit 1
fi
if [ "$skip" -gt 0 ]; then
  echo "VERDICT: PASS (with $skip check(s) skipped - integrity shown; see SKIP lines for what was not proven)"
else
  echo "VERDICT: PASS - integrity, authenticity and build provenance all verified."
fi
exit 0