# tests/services/test_recurring.py
import datetime
from sqlalchemy import create_engine
from sqlalchemy.orm import Session

from src.db import Base
from src.models import *
from src.services.recurring import RecurringDetector


def make_session():
    engine = create_engine("sqlite:///:memory:")
    Base.metadata.create_all(engine)
    return Session(engine)


def make_recurring_data(session):
    member = HouseholdMember(name="Andrew", relationship="self")
    session.add(member)
    session.flush()
    account = Account(name="Checking", institution="WF", account_type="checking", owner_id=member.id)
    session.add(account)
    session.flush()

    # Netflix monthly: ~$19.07 on 3rd/4th of month
    for month in [1, 2]:
        session.add(Transaction(
            date=datetime.date(2026, month, 4),
            amount=-19.07, description="Netflix.com", account_id=account.id,
        ))

    # HelloFresh weekly: ~$142.87
    for day in [1, 8, 15, 22, 29]:
        session.add(Transaction(
            date=datetime.date(2026, 1, day),
            amount=-142.87, description="HELLOFRESH", account_id=account.id,
        ))

    # Random one-off purchase
    session.add(Transaction(
        date=datetime.date(2026, 1, 10),
        amount=-95.38, description="CARL'S GOLFLAND INC", account_id=account.id,
    ))

    session.commit()
    return account


def test_detect_monthly_recurring():
    session = make_session()
    make_recurring_data(session)
    detector = RecurringDetector(session)
    results = detector.detect()
    netflix = [r for r in results if "Netflix" in r["description"]]
    assert len(netflix) == 1
    assert netflix[0]["frequency"] == "monthly"
    assert abs(netflix[0]["typical_amount"] - 19.07) < 0.01


def test_detect_weekly_recurring():
    session = make_session()
    make_recurring_data(session)
    detector = RecurringDetector(session)
    results = detector.detect()
    hello = [r for r in results if "HELLOFRESH" in r["description"]]
    assert len(hello) == 1
    assert hello[0]["frequency"] == "weekly"


def test_one_off_not_detected():
    session = make_session()
    make_recurring_data(session)
    detector = RecurringDetector(session)
    results = detector.detect()
    golf = [r for r in results if "GOLFLAND" in r["description"]]
    assert len(golf) == 0


def test_annual_cost_calculation():
    session = make_session()
    make_recurring_data(session)
    detector = RecurringDetector(session)
    results = detector.detect()
    netflix = [r for r in results if "Netflix" in r["description"]][0]
    assert abs(netflix["annual_cost"] - 19.07 * 12) < 1.0