#!/usr/bin/env python3
"""Independent checker for the CAIN-42 hardening bundle. Imports NOTHING from CAIN; needs Python 3 and (for the
signature check) the `cryptography` package.

  python3 verify_bundle.py [DIR_OR_BASE_URL]      (published as verify_bundle.py.txt: save without the .txt)

Checks: (1) every file's SHA-256 and size match manifest.json; (2) the Merkle-style root matches; (3) the Ed25519
signature over the canonical manifest verifies against the embedded public key; (4) every number in manifest["claims"]
is RECOMPUTED from the bundle's own files and must match. It does NOT re-run the tests: the commands to do that
are in REPRODUCE.txt. Exit code 0 only if every check passes.
"""
import base64, hashlib, json, re, sys, urllib.request
from pathlib import Path

src = sys.argv[1] if len(sys.argv) > 1 else "."
def read(name):
    if src.startswith("http"):
        return urllib.request.urlopen(src.rstrip("/") + "/" + name, timeout=30).read()
    return (Path(src) / name).read_bytes()

problems = []
m = json.loads(read("manifest.json"))
sha = lambda b: hashlib.sha256(b).hexdigest()
leaves = []
for f in m["files"]:
    try:
        b = read(f["path"])
    except Exception as e:
        problems.append(f"cannot read {f['path']}: {e}"); continue
    if sha(b) != f["sha256"] or len(b) != f["bytes"]:
        problems.append(f"HASH/SIZE MISMATCH {f['path']}")
    leaves.append(f["sha256"])
root = sha("\n".join(sorted(leaves)).encode())
if root != m["bundle_root"]:
    problems.append("bundle_root mismatch")

def canon(o): return json.dumps(o, sort_keys=True, separators=(",", ":")).encode()
body = {k: v for k, v in m.items() if k not in ("signature",)}
try:
    from cryptography.hazmat.primitives.asymmetric.ed25519 import Ed25519PublicKey
    Ed25519PublicKey.from_public_bytes(base64.b64decode(m["signer_public_key"])).verify(base64.b64decode(m["signature"]), canon(body))
    sig = "valid"
except ImportError:
    sig = "SKIPPED (cryptography not installed)"
except Exception:
    sig = "INVALID"; problems.append("signature invalid")

adv = json.loads(read("adversarial-suite-run.json"))["attacks"]
c = {}
for a in adv: c[a["result"]] = c.get(a["result"], 0) + 1
fi = json.loads(read("formal-invariants-run.json"))
bm = json.loads(read("benchmark.json"))
tr = read("test-run.txt").decode()
passed = sum(int(x) for x in re.findall(r"(\d+) passed", tr)); failed = sum(int(x) for x in re.findall(r"(\d+) failed", tr))
derived = {
    "adversarial_total": len(adv), "adversarial_blocked": c.get("ATTACK_BLOCKED", 0),
    "adversarial_inconclusive": c.get("INCONCLUSIVE", 0), "adversarial_succeeded": c.get("ATTACK_SUCCEEDED", 0),
    "formal_passed": fi["passed"], "formal_total": fi["total"],
    "benchmark_sustained_iterations": bm["duration_tests"]["1_minute_sustained_load"]["iterations"],
    "benchmark_sustained_elapsed_s": bm["duration_tests"]["1_minute_sustained_load"]["elapsed_s"],
    "test_run_passed": passed, "test_run_failed": failed,
}
for k, v in derived.items():
    if m["claims"].get(k) != v:
        problems.append(f"claim {k}: manifest says {m['claims'].get(k)!r}, files give {v!r}")
print(json.dumps({"bundle": m["bundle_id"], "files": len(m["files"]), "signature": sig, "derived": derived}, indent=1))
print("VALID" if not problems else "INVALID:\n  " + "\n  ".join(problems))
sys.exit(0 if not problems else 1)