from datetime import date, timedelta
from decimal import Decimal

import pytest

from app.models.tables import Account, Category, Transaction

H = {"Authorization": "Bearer test-key"}


def _tx(db, acc, day, amount, purpose="Zweck", counterparty="X", category=None, n=[0]):
    n[0] += 1
    db.add(Transaction(account_id=acc.id, booking_date=day, amount=Decimal(amount),
                       purpose=purpose, counterparty=counterparty, status="confirmed",
                       category_id=category.id if category else None,
                       dedup_hash=f"sort-{n[0]}"))


@pytest.fixture
def small(db):
    zeta = Account(bank="t", iban="DE-SO-1", name="Zeta", type="giro")
    alpha = Account(bank="t", iban="DE-SO-2", name="alpha", type="giro")
    kat = Category(name="Miete")
    db.add_all([zeta, alpha, kat])
    db.flush()
    _tx(db, zeta, date(2026, 1, 3), "-5.00", "b-Zweck", "Bert", kat)
    _tx(db, alpha, date(2026, 1, 1), "20.00", "A-Zweck", "anna", None)
    _tx(db, zeta, date(2026, 1, 2), "-30.00", "c-Zweck", "Carl", kat)
    db.commit()


def _amounts(client, qs):
    r = client.get(f"/api/transactions?{qs}", headers=H)
    assert r.status_code == 200
    return [Decimal(t["amount"]) for t in r.json()]


def test_standard_bleibt_datum_aufsteigend(client, small):
    assert _amounts(client, "") == [Decimal("20.00"), Decimal("-30.00"), Decimal("-5.00")]


@pytest.mark.parametrize("sort,dir,expected", [
    ("betrag", "asc", ["-30.00", "-5.00", "20.00"]),
    ("betrag", "desc", ["20.00", "-5.00", "-30.00"]),
    ("datum", "desc", ["-5.00", "-30.00", "20.00"]),
    ("konto", "asc", ["20.00", "-5.00", "-30.00"]),       # alpha vor Zeta (case-insensitiv), Gleichstand -> id
    ("zweck", "asc", ["20.00", "-5.00", "-30.00"]),       # A-, b-, c-Zweck
    ("empfaenger", "desc", ["-30.00", "-5.00", "20.00"]),  # Carl, Bert, anna
    ("kategorie", "asc", ["-5.00", "-30.00", "20.00"]),   # Miete (id-Reihenfolge), unkategorisiert zuletzt
    ("kategorie", "desc", ["-30.00", "-5.00", "20.00"]),  # unkategorisiert auch absteigend zuletzt
])
def test_sortierung_je_spalte(client, small, sort, dir, expected):
    assert _amounts(client, f"sort={sort}&dir={dir}") == [Decimal(e) for e in expected]


def test_ungueltige_werte_fallen_auf_standard(client, small):
    assert _amounts(client, "sort=foo;drop&dir=hoch") == _amounts(client, "")
    client.post("/login", data={"username": "admin", "password": "geheim"})
    assert client.get("/buchungen?sort=foo&dir=bar").status_code == 200


@pytest.fixture
def many(db):
    acc = Account(bank="t", iban="DE-SO-3", name="Viel", type="giro")
    db.add(acc)
    db.flush()
    for i in range(1, 61):  # Beträge i,37; Datum verwürfelt
        _tx(db, acc, date(2026, 1, 1) + timedelta(days=(i * 7) % 60), f"{i}.37", f"Miete {i}")
    db.commit()


def test_sortierung_gilt_ueber_alle_seiten(client, many):
    client.post("/login", data={"username": "admin", "password": "geheim"})
    p1 = client.get("/buchungen?sort=betrag&dir=desc").text
    p2 = client.get("/buchungen?sort=betrag&dir=desc&page=2").text
    assert ">60,37</td>" in p1 and ">1,37</td>" not in p1
    assert ">1,37</td>" in p2 and ">60,37</td>" not in p2


def test_links_erhalten_filter_und_sortierung(client, many):
    client.post("/login", data={"username": "admin", "password": "geheim"})
    html = client.get("/buchungen?q=Miete&sort=betrag&dir=asc").text
    # Aktiver Spaltenkopf kehrt die Richtung um, übernimmt den Filter, ohne page.
    assert 'href="/buchungen?q=Miete&status=confirmed&sort=betrag&dir=desc"' in html
    # Inaktive Spalte startet aufsteigend.
    assert 'href="/buchungen?q=Miete&status=confirmed&sort=datum&dir=asc"' in html
    # Pager behält Filter + Sortierung.
    assert "q=Miete&status=confirmed&sort=betrag&dir=asc&page=2" in html
    assert "▲" in html