from __future__ import annotations

from datetime import date
from decimal import Decimal

from mousehold_api import models
from mousehold_api.schemas import ManualObservationCreate
from mousehold_api.services.ingestion import create_observation_with_candidate
from mousehold_api.services.reconciliation import (
    accept_reconciliation_suggestion,
    ignore_reconciliation_suggestion,
    list_reconciliation_decisions,
    list_reconciliation_suggestions,
)
from mousehold_domain import (
    EventObservationRelation,
    FinancialEventStatus,
    FinancialEventType,
    RelationType,
    SourceType,
)
from sqlalchemy import select
from sqlalchemy.orm import Session


def test_paypal_email_is_matched_to_paypal_statement(
    session: Session,
    household_setup: dict[str, str],
) -> None:
    email_event = _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.PAYPAL_EMAIL,
        source_reference="paypal-email-1",
        amount=Decimal("18.99"),
        event_date=date(2026, 1, 5),
        due_date=date(2026, 1, 8),
        merchant="Example Merchant",
        description="PayPal payment to Example Merchant",
        status=None,
    )
    statement_event = _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.PAYPAL_CSV,
        source_reference="PAYPAL-TXN-1",
        provider_transaction_id="PAYPAL-TXN-1",
        amount=Decimal("18.99"),
        event_date=date(2026, 1, 6),
        merchant="Example Merchant",
        description="Payment Sent",
        status=FinancialEventStatus.CONFIRMED,
    )
    session.commit()

    suggestions = list_reconciliation_suggestions(
        session,
        household_id=household_setup["household_id"],
    )

    assert len(suggestions) == 1
    assert suggestions[0].primary_event.id == email_event.id
    assert suggestions[0].confirming_event.id == statement_event.id
    assert suggestions[0].confidence >= Decimal("0.80")


def test_accepting_suggestion_confirms_primary_and_links_evidence(
    session: Session,
    household_setup: dict[str, str],
) -> None:
    email_event = _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.KLARNA_EMAIL,
        source_reference="klarna-email-1",
        amount=Decimal("84.00"),
        event_date=date(2026, 2, 1),
        due_date=date(2026, 2, 14),
        merchant="Example Shop",
        description="Klarna payment reference KR-123",
        raw_payload_json={"references": {"klarna_reference": "KR-123"}},
        status=None,
    )
    _statement_event = _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.KLARNA_CSV,
        source_reference="KR-123",
        provider_transaction_id="KR-123",
        amount=Decimal("84.00"),
        event_date=date(2026, 2, 8),
        merchant="Example Shop",
        description="Klarna payment",
        status=FinancialEventStatus.CONFIRMED,
    )
    session.commit()
    suggestion = list_reconciliation_suggestions(
        session,
        household_id=household_setup["household_id"],
    )[0]

    accept_reconciliation_suggestion(
        session,
        household_id=household_setup["household_id"],
        suggestion_id=suggestion.id,
    )
    session.commit()
    session.refresh(email_event)

    assert email_event.status == FinancialEventStatus.CONFIRMED
    relation = session.scalars(select(models.EventRelation)).one()
    assert relation.from_event_id == suggestion.primary_event.id
    assert relation.to_event_id == suggestion.confirming_event.id
    evidence_link = session.scalars(
        select(models.EventObservationLink)
        .where(models.EventObservationLink.event_id == email_event.id)
        .where(models.EventObservationLink.relation == EventObservationRelation.EVIDENCE_FOR)
    ).first()
    assert evidence_link is not None
    assert list_reconciliation_suggestions(session, household_id=household_setup["household_id"]) == []


def test_different_amounts_do_not_match(
    session: Session,
    household_setup: dict[str, str],
) -> None:
    _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.PAYPAL_EMAIL,
        source_reference="paypal-email-2",
        amount=Decimal("18.99"),
        event_date=date(2026, 1, 5),
        merchant="Example Merchant",
        description="PayPal payment",
        status=None,
    )
    _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.PAYPAL_CSV,
        source_reference="PAYPAL-TXN-2",
        amount=Decimal("19.99"),
        event_date=date(2026, 1, 6),
        merchant="Example Merchant",
        description="Payment Sent",
        status=FinancialEventStatus.CONFIRMED,
    )
    session.commit()

    assert list_reconciliation_suggestions(session, household_id=household_setup["household_id"]) == []


def test_ignored_suggestion_is_persistently_hidden(
    session: Session,
    household_setup: dict[str, str],
) -> None:
    _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.PAYPAL_EMAIL,
        source_reference="paypal-email-ignore",
        amount=Decimal("12.00"),
        event_date=date(2026, 1, 5),
        due_date=date(2026, 1, 8),
        merchant="Example Merchant",
        description="PayPal payment to Example Merchant",
        status=None,
    )
    _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.PAYPAL_CSV,
        source_reference="PAYPAL-TXN-IGNORE",
        provider_transaction_id="PAYPAL-TXN-IGNORE",
        amount=Decimal("12.00"),
        event_date=date(2026, 1, 6),
        merchant="Example Merchant",
        description="Payment Sent",
        status=FinancialEventStatus.CONFIRMED,
    )
    session.commit()
    suggestion = list_reconciliation_suggestions(
        session,
        household_id=household_setup["household_id"],
    )[0]

    _ignored, decision = ignore_reconciliation_suggestion(
        session,
        household_id=household_setup["household_id"],
        suggestion_id=suggestion.id,
        actor_user_id=household_setup["user_a_id"],
        reason="not the same payment",
    )
    session.commit()

    assert decision.decision == "ignored"
    assert list_reconciliation_suggestions(session, household_id=household_setup["household_id"]) == []
    decisions = list_reconciliation_decisions(session, household_id=household_setup["household_id"])
    assert decisions[0].suggestion_id == suggestion.id


def test_paypal_obligation_statement_and_bank_debit_lifecycle(
    session: Session,
    household_setup: dict[str, str],
) -> None:
    email_event = _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.PAYPAL_EMAIL,
        source_reference="paypal-email-lifecycle",
        amount=Decimal("84.00"),
        event_date=date(2026, 1, 5),
        due_date=date(2026, 2, 4),
        merchant="Example Merchant",
        description="PayPal promised payment to Example Merchant",
        status=None,
        event_type=FinancialEventType.PROMISED_PAYMENT,
    )
    statement_event = _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.PAYPAL_CSV,
        source_reference="PAYPAL-LIFECYCLE",
        provider_transaction_id="PAYPAL-LIFECYCLE",
        amount=Decimal("84.00"),
        event_date=date(2026, 1, 6),
        merchant="Example Merchant",
        description="PayPal payment to Example Merchant",
        status=FinancialEventStatus.CONFIRMED,
    )
    bank_event = _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.FINTS,
        source_reference="BANK-PAYPAL-LIFECYCLE",
        provider_transaction_id="BANK-PAYPAL-LIFECYCLE",
        amount=Decimal("84.00"),
        event_date=date(2026, 2, 4),
        merchant="PayPal Europe",
        description="PayPal funding debit",
        status=FinancialEventStatus.CONFIRMED,
    )
    session.commit()

    first = list_reconciliation_suggestions(session, household_id=household_setup["household_id"])[0]
    assert first.primary_event.id == email_event.id
    assert first.confirming_event.id == statement_event.id
    accept_reconciliation_suggestion(
        session,
        household_id=household_setup["household_id"],
        suggestion_id=first.id,
    )
    session.commit()

    session.refresh(email_event)
    session.refresh(bank_event)
    assert email_event.status == FinancialEventStatus.CONFIRMED
    assert bank_event.event_type == FinancialEventType.LIABILITY_PAYMENT

    second = list_reconciliation_suggestions(session, household_id=household_setup["household_id"])[0]
    assert second.primary_event.id == statement_event.id
    assert second.confirming_event.id == bank_event.id
    assert second.relation_type == RelationType.SETTLES
    accept_reconciliation_suggestion(
        session,
        household_id=household_setup["household_id"],
        suggestion_id=second.id,
    )
    session.commit()

    relations = list(session.scalars(select(models.EventRelation)).all())
    assert {relation.relation_type for relation in relations} == {
        RelationType.SAME_ECONOMIC_EVENT_AS,
        RelationType.SETTLES,
    }
    expense_events = list(
        session.scalars(
            select(models.FinancialEvent)
            .where(models.FinancialEvent.household_id == household_setup["household_id"])
            .where(models.FinancialEvent.event_type == FinancialEventType.EXPENSE)
        ).all()
    )
    assert [event.id for event in expense_events] == [statement_event.id]


def test_klarna_obligation_statement_and_bank_debit_lifecycle(
    session: Session,
    household_setup: dict[str, str],
) -> None:
    email_event = _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.KLARNA_EMAIL,
        source_reference="klarna-email-lifecycle",
        amount=Decimal("64.00"),
        event_date=date(2026, 3, 1),
        due_date=date(2026, 3, 31),
        merchant="Example Shop",
        description="Klarna payment reference KR-456",
        raw_payload_json={"references": {"klarna_reference": "KR-456"}},
        status=None,
        event_type=FinancialEventType.PROMISED_PAYMENT,
    )
    statement_event = _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.KLARNA_CSV,
        source_reference="KR-456",
        provider_transaction_id="KR-456",
        amount=Decimal("64.00"),
        event_date=date(2026, 3, 5),
        merchant="Example Shop",
        description="Klarna payment KR-456",
        status=FinancialEventStatus.CONFIRMED,
    )
    bank_event = _create_observation_event(
        session,
        household_id=household_setup["household_id"],
        owner_user_id=household_setup["user_a_id"],
        source_type=SourceType.FINTS,
        source_reference="BANK-KLARNA-LIFECYCLE",
        provider_transaction_id="BANK-KLARNA-LIFECYCLE",
        amount=Decimal("64.00"),
        event_date=date(2026, 3, 31),
        merchant="Klarna Bank AB",
        description="Klarna funding debit",
        status=FinancialEventStatus.CONFIRMED,
    )
    session.commit()

    first = list_reconciliation_suggestions(session, household_id=household_setup["household_id"])[0]
    assert first.primary_event.id == email_event.id
    assert first.confirming_event.id == statement_event.id
    accept_reconciliation_suggestion(
        session,
        household_id=household_setup["household_id"],
        suggestion_id=first.id,
    )
    session.commit()

    session.refresh(bank_event)
    assert bank_event.event_type == FinancialEventType.LIABILITY_PAYMENT

    second = list_reconciliation_suggestions(session, household_id=household_setup["household_id"])[0]
    assert second.primary_event.id == statement_event.id
    assert second.confirming_event.id == bank_event.id
    assert second.relation_type == RelationType.SETTLES


def _create_observation_event(
    session: Session,
    *,
    household_id: str,
    owner_user_id: str,
    source_type: SourceType,
    source_reference: str,
    amount: Decimal,
    event_date: date,
    merchant: str,
    description: str,
    provider_transaction_id: str | None = None,
    due_date: date | None = None,
    raw_payload_json: dict | None = None,
    status: FinancialEventStatus | None,
    event_type: FinancialEventType = FinancialEventType.EXPENSE,
) -> models.FinancialEvent:
    _observation, event = create_observation_with_candidate(
        session,
        ManualObservationCreate(
            household_id=household_id,
            source_type=source_type,
            owner_user_id=owner_user_id,
            source_reference=source_reference,
            provider_transaction_id=provider_transaction_id,
            raw_payload_json=raw_payload_json,
            amount=amount,
            currency="EUR",
            event_date=event_date,
            due_date=due_date,
            merchant=merchant,
            description=description,
            status=status,
            event_type=event_type,
        ),
    )
    assert event is not None
    return event