import json
import re
from decimal import Decimal
from pathlib import Path

import pytest

from app.parsers.registry import parse_pdf
from app.parsers.validate import balance_difference

FIXTURES = Path(__file__).parent / "fixtures"
CASES = [("vr_beispiel.pdf", "vr"), ("hvb_beispiel.pdf", "hvb"),
         ("dkb_beispiel.pdf", "dkb")]

NOISE = re.compile(
    r"(Kontostand|Übertrag|alter Saldo|neuer Saldo|Seite \d|Blatt \d)", re.I)


@pytest.mark.parametrize("filename,bank", CASES)
def test_parse_fixture(filename, bank):
    path = FIXTURES / filename
    if not path.exists():
        pytest.skip(f"Fixture {filename} fehlt")
    stmt = parse_pdf(path)
    assert stmt.bank == bank
    assert stmt.opening_balance is not None
    assert stmt.closing_balance is not None
    assert len(stmt.transactions) > 0
    assert balance_difference(stmt) == Decimal("0")


@pytest.mark.parametrize("filename,bank", CASES)
def test_no_noise_in_parsed_fields(filename, bank):
    path = FIXTURES / filename
    if not path.exists():
        pytest.skip(f"Fixture {filename} fehlt")
    stmt = parse_pdf(path)
    for t in stmt.transactions:
        assert not NOISE.search(t.purpose), f"Noise im Verwendungszweck: #{stmt.transactions.index(t)}"
        assert not NOISE.search(t.counterparty), f"Noise im Empfänger: #{stmt.transactions.index(t)}"
        assert stmt.period_start <= t.booking_date <= stmt.period_end


@pytest.mark.parametrize("filename,bank", CASES)
def test_expected_values(filename, bank):
    path = FIXTURES / filename
    exp_path = FIXTURES / f"expected_{bank}.json"
    if not path.exists() or not exp_path.exists():
        pytest.skip("Fixture oder expected-Datei fehlt")
    stmt = parse_pdf(path)
    exp = json.loads(exp_path.read_text())
    assert len(stmt.transactions) == exp["transaction_count"]
    for c in exp["spot_checks"]:
        t = stmt.transactions[c["index"]]
        assert str(t.booking_date) == c["booking_date"]
        assert str(t.amount) == c["amount"]
        assert c["counterparty_contains"].lower() in t.counterparty.lower()
        assert c["purpose_contains"].lower() in t.purpose.lower()