QWED Finance guards for financial AI verification

from qwed_finance import ComplianceGuard

guard = ComplianceGuard()

# AML Threshold Check (BSA/FinCEN)
result = guard.verify_aml_flag(
    amount=15000,
    country_code="US",
    llm_flagged=True
)
# result.compliant = True ✅
# result.proof = "amount >= 10000 → CTR required"

# Z3 proves: IF amount >= 10000 THEN flag_required
from z3 import *
amount = Real('amount')
flag = Bool('flag')
solver = Solver()
solver.add(Implies(amount >= 10000, flag == True))

from qwed_finance import CalendarGuard, DayCountConvention
from datetime import date

guard = CalendarGuard()

# Verify 30/360 day count
result = guard.verify_day_count(
    start_date=date(2026, 1, 1),
    end_date=date(2026, 7, 1),
    llm_days=180,
    convention=DayCountConvention.THIRTY_360
)
# result.verified = True ✅

from qwed_finance import DerivativesGuard, OptionType

guard = DerivativesGuard()

# Verify Black-Scholes call price
result = guard.verify_black_scholes(
    spot_price=100,
    strike_price=105,
    time_to_expiry=0.25,
    risk_free_rate=0.05,
    volatility=0.20,
    option_type=OptionType.CALL,
    llm_price="$3.50"
)
# result.greeks = {"delta": "0.4502", "gamma": "0.0389", ...}

from qwed_finance import MessageGuard, MessageType

guard = MessageGuard()

# Verify pacs.008 payment message
result = guard.verify_iso20022_xml(
    xml_string=pacs008_xml,
    msg_type=MessageType.PACS_008
)
# result.valid = True/False
# result.errors = ["Missing required element: GrpHdr"]

# Validate MT103 fields
result = guard.verify_swift_mt(
    mt_string=mt103_message,
    mt_type=SwiftMtType.MT103
)
# Checks Field 20, 32A, 50K, 59, etc.

from qwed_finance import ISOGuard

guard = ISOGuard()

# Verify pacs.008 (JSON format)
result = guard.verify_payment_message(
    message={
        "MsgId": "1234AB",
        "CreDtTm": "2026-01-28T10:00:00",
        "NbOfTxs": 1,
        "TtlIntrBkSttlmAmt": {"amount": 100.50, "currency": "USD"}
    },
    msg_type="pacs.008"
)
# result.verified = True ✅

from qwed_finance import QueryGuard

guard = QueryGuard(allowed_tables={"transactions", "accounts"})

# Check read-only safety
result = guard.verify_readonly_safety(
    "DELETE FROM users WHERE id=1"
)
# result.safe = False ❌
# result.violations = ["Mutation detected: DELETE statement"]

-- Regex might miss this:
SELECT * FROM (DELETE FROM users RETURNING *) AS x

-- SQLGlot AST catches it by parsing the tree structure

from qwed_finance import CrossGuard

guard = CrossGuard()

# SWIFT + Sanctions in one call
result = guard.verify_swift_with_sanctions(
    mt_string=swift_message,
    sanctions_list=["ACME Corp", "Bad Bank LLC"]
)
# Validates SWIFT format AND screens entities

from qwed_finance import BondGuard

guard = BondGuard()

# Verify YTM calculation
result = guard.verify_ytm(
    face_value=1000,
    coupon_rate=0.05,
    price=950,
    years_to_maturity=10,
    llm_output="5.66%"
)
# result.verified = True ✅
# result.computed_ytm = 0.0566...

# ✅ Correct: use explicit % for percentage values
guard.verify_ytm(..., llm_output="5.25%")

# ✅ Correct: use decimal fraction directly
guard.verify_ytm(..., llm_output="0.0525")

# ⚠️ Breaking: "5.25" now means 525%, NOT 5.25%
# Use "5.25%" instead

from qwed_finance import FXGuard

guard = FXGuard()

# Verify Spot Conversion
result = guard.verify_conversion(
    amount=1000,
    from_currency="USD",
    to_currency="EUR",
    rate=0.92,
    llm_output="920.00 EUR"
)
# result.verified = True ✅

from qwed_finance import RiskGuard

guard = RiskGuard()

# Verify Sharpe Ratio
# (Return - RiskFree) / Volatility
result = guard.verify_sharpe_ratio(
    portfolio_return=0.12,
    risk_free_rate=0.03,
    volatility=0.15,
    llm_output="0.60" 
)
# result.verified = True ✅
# result.computed_sharpe = 0.60