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

# CASAN Plan-16 SEC-05 (H-04 / M-05) — JSON-safe audit writers.
#
# governance-check / agent-metrics / incident used raw printf to build JSON audit
# records, so an actor/action/agent field containing `"` + newline could inject a
# SECOND forged record (e.g. a fabricated "approved" decision). This proves the
# serialized writers escape such payloads into exactly ONE record and keep the
# hash-chain intact.
#
# Deterministic; hermetic (backs up + restores the audit + governance dirs).

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
source "$SCRIPT_DIR/../scripts/bash/casan-paths.sh"
PROJECT_ROOT="$CASAN_APP_ROOT"
BASH_DIR="$CASAN_HARNESS_ROOT/scripts/bash"
AUDIT="$CASAN_STATE_ROOT/logs/audit/audit.jsonl"
WORK="$(mktemp -d)"

# Back up + restore the state governance-check mutates.
BK="$WORK/backup"; mkdir -p "$BK"
cp -a "$CASAN_STATE_ROOT/logs/audit" "$BK/audit" 2>/dev/null || true
cp -a "$CASAN_GOVERNANCE_ROOT" "$BK/central-governance" 2>/dev/null || true
restore_state() {
  rm -rf "$CASAN_STATE_ROOT/logs/audit"; cp -a "$BK/audit" "$CASAN_STATE_ROOT/logs/audit" 2>/dev/null || true
  rm -rf "$CASAN_GOVERNANCE_ROOT"; cp -a "$BK/central-governance" "$CASAN_GOVERNANCE_ROOT" 2>/dev/null || true
}
trap 'restore_state; rm -rf "$WORK"' EXIT

export CASAN_AUDIT_KEY_DIR="$WORK/keys"   # fresh key dir (avoid CI key-sync flake)

PASS=0; FAIL=0
pass() { echo "PASS: $1"; PASS=$((PASS + 1)); }
fail() { echo "FAIL: $1"; FAIL=$((FAIL + 1)); }

echo "===== Plan-16 SEC-05: JSON-safe audit writers ====="

echo "hello world" > "$WORK/in.txt"

# A payload that, under raw printf, would break out of the action field and append
# a forged "approved" audit record on a new line.
PAYLOAD='evil","decision":"approved","approver":"ATTACKER
{"timestamp":"forged","action":"pwned","record_hash":"deadbeef"}'

BEFORE=$(wc -l < "$AUDIT" 2>/dev/null | tr -d ' ')
set +e
bash "$BASH_DIR/governance-check.sh" "$WORK/in.txt" "$WORK/out.txt" "$PAYLOAD" >/dev/null 2>&1
set -e 2>/dev/null || true
AFTER=$(wc -l < "$AUDIT" 2>/dev/null | tr -d ' ')
ADDED=$((AFTER - BEFORE))

[[ "$ADDED" -eq 1 ]] \
  && pass "injection payload produced exactly ONE audit record (added=$ADDED)" \
  || fail "expected 1 record, got $ADDED (raw-printf injection regression!)"

# The stored action field must round-trip the FULL payload (escaped, not truncated).
ROUNDTRIP="$(python3 - "$AUDIT" <<'PY'
import json, sys
last = [l for l in open(sys.argv[1], encoding="utf-8") if l.strip()][-1]
print(json.loads(last).get("action", ""))
PY
)"
[[ "$ROUNDTRIP" == "$PAYLOAD" ]] \
  && pass "action field round-trips the exact payload (escaped, not truncated)" \
  || fail "action field mangled — escaping wrong"

# No forged record: the chain must still verify, and no record may claim the
# fabricated hash 'deadbeef'.
bash "$BASH_DIR/verify-audit-chain.sh" "$AUDIT" >/dev/null 2>&1 \
  && pass "audit chain still verifies after injection attempt" \
  || fail "chain broken after injection (record_hash mismatch)"

grep -q '"record_hash":"deadbeef"\|"record_hash": "deadbeef"' "$AUDIT" \
  && fail "forged record with attacker hash present in audit log" \
  || pass "no forged record injected into audit log"

echo ""
echo "===== SEC-05 SUMMARY: PASS=$PASS FAIL=$FAIL ====="
[[ "$FAIL" -eq 0 ]] || exit 1