"""Schlagwörter je Kategorie: Anlegen/Konflikt, Treffer (Empfänger ODER Zweck),
längstes gewinnt, Kind-Filter, Korrektur-Erkennung/Flagging, keine Rückwirkung."""

import io
import json


def _account(admin, **kw):
    body = {"name": "Giro", "type": "girokonto", "currency": "EUR", "opening_balance_cents": 0}
    body.update(kw)
    r = admin.post("/api/accounts", json=body)
    assert r.status_code == 201, r.text
    return r.json()


def _expense_cats(admin, n=2):
    out = []
    for g in admin.get("/api/categories").json():
        if g["kind"] == "expense":
            out += g["categories"]
    assert len(out) >= n, "zu wenige Ausgabe-Kategorien im Seed"
    return out[:n]


def _income_cat(admin):
    for g in admin.get("/api/categories").json():
        if g["kind"] == "income" and g["categories"]:
            return g["categories"][0]
    raise AssertionError("keine Einnahme-Kategorie im Seed")


def _preview_csv(admin, account_id, csv, colmap):
    r = admin.post(
        "/api/imports/preview",
        files={"file": ("k.csv", io.BytesIO(csv.encode("utf-8")), "text/csv")},
        data={
            "account_id": str(account_id), "delimiter": ";", "decimal_sep": ",",
            "date_format": "%d.%m.%Y", "encoding": "utf-8", "has_header": "true",
            "skip_rows": "0", "amount_mode": "signed", "column_map": colmap,
        },
    )
    assert r.status_code == 200, r.text
    return r.json()["rows"]


COLMAP = json.dumps({"date": 0, "amount": 1, "payee": 2, "purpose": 3})


def test_keyword_crud_and_conflict(admin):
    a, b = _expense_cats(admin, 2)
    r = admin.post(f"/api/categories/{a['id']}/keywords", json={"word": "  REWE  "})
    assert r.status_code == 201, r.text
    assert r.json()["word"] == "rewe"  # getrimmt + kleingeschrieben
    kid = r.json()["id"]

    assert [k["word"] for k in admin.get(f"/api/categories/{a['id']}/keywords").json()] == ["rewe"]

    # Gleiches Wort, gleiche Kategorie -> idempotent, keine Dublette.
    assert admin.post(f"/api/categories/{a['id']}/keywords", json={"word": "rewe"}).status_code == 201
    assert len(admin.get(f"/api/categories/{a['id']}/keywords").json()) == 1

    # Gleiches Wort, andere Kategorie -> Konflikt.
    assert admin.post(f"/api/categories/{b['id']}/keywords", json={"word": "rewe"}).status_code == 409

    assert admin.delete(f"/api/categories/keywords/{kid}").status_code == 204
    assert admin.get(f"/api/categories/{a['id']}/keywords").json() == []


def test_matching_payee_purpose_and_kind_filter(admin):
    giro = _account(admin, name="Giro KW")
    a, _ = _expense_cats(admin, 2)
    admin.post(f"/api/categories/{a['id']}/keywords", json={"word": "netflix"})

    csv = (
        "Datum;Betrag;Empfaenger;Zweck\n"
        "01.03.2026;-9,99;NETFLIX;Abo\n"                    # Empfänger-Treffer
        "02.03.2026;-9,99;Kartenzahlung;NETFLIX Monatsabo\n"  # Zweck-Treffer (any)
        "03.03.2026;9,99;NETFLIX;Erstattung\n"             # Einnahme -> darf NICHT greifen
    )
    rows = _preview_csv(admin, giro["id"], csv, COLMAP)
    assert rows[0]["category_id"] == a["id"]
    assert rows[0]["matched_rule_id"] is not None
    assert rows[1]["category_id"] == a["id"]      # über den Zweck getroffen
    assert rows[2]["category_id"] is None          # Ausgabe-Schlagwort, Einnahme -> gefiltert


def test_longest_keyword_wins(admin):
    giro = _account(admin, name="Giro LW")
    a, b = _expense_cats(admin, 2)
    admin.post(f"/api/categories/{a['id']}/keywords", json={"word": "rewe"})
    admin.post(f"/api/categories/{b['id']}/keywords", json={"word": "rewe getraenke"})

    csv = "Datum;Betrag;Empfaenger;Zweck\n01.03.2026;-20,00;REWE Getraenke Markt;Wasser\n"
    rows = _preview_csv(admin, giro["id"], csv, COLMAP)
    assert rows[0]["category_id"] == b["id"]  # spezifischeres (längeres) Schlagwort gewinnt


def test_correction_flagging_confirm(admin):
    giro = _account(admin, name="Giro Flag")
    a, b = _expense_cats(admin, 2)
    kw = admin.post(f"/api/categories/{a['id']}/keywords", json={"word": "spotify"}).json()

    lines = "".join(f"0{i}.03.2026;-9,99;SPOTIFY;Abo\n" for i in range(1, 7))  # 6 Zeilen
    rows = _preview_csv(admin, giro["id"], "Datum;Betrag;Empfaenger;Zweck\n" + lines, COLMAP)
    assert len(rows) == 6 and all(r["category_id"] == a["id"] for r in rows)

    for r in rows[:2]:  # zwei wegkorrigieren
        r["category_id"] = b["id"]
    res = admin.post("/api/imports/commit", json={"account_id": giro["id"], "filename": "s.csv", "rows": rows})
    assert res.status_code == 200, res.text

    flagged = admin.get("/api/categories/keywords/flagged").json()
    hit = next((f for f in flagged if f["id"] == kw["id"]), None)
    assert hit is not None, flagged
    assert hit["applied_count"] == 6 and hit["overridden_count"] == 2

    # „Behalten" unterdrückt die Meldung künftig.
    assert admin.post(f"/api/categories/keywords/{kw['id']}/confirm").status_code == 204
    assert kw["id"] not in [f["id"] for f in admin.get("/api/categories/keywords/flagged").json()]


def test_keyword_update_and_conflict(admin):
    a, b = _expense_cats(admin, 2)
    kw = admin.post(f"/api/categories/{a['id']}/keywords", json={"word": "lidil"}).json()

    r = admin.patch(f"/api/categories/keywords/{kw['id']}", json={"word": "  LIDL  "})
    assert r.status_code == 200, r.text
    assert r.json()["word"] == "lidl"  # getrimmt + kleingeschrieben
    words = admin.get(f"/api/categories/{a['id']}/keywords").json()
    assert next(k for k in words if k["id"] == kw["id"])["word"] == "lidl"
    assert "lidil" not in [k["word"] for k in words]  # altes Wort ist weg

    # Umbenennen auf ein Wort, das schon einer anderen Kategorie gehört -> Konflikt.
    admin.post(f"/api/categories/{b['id']}/keywords", json={"word": "coop"})
    assert admin.patch(f"/api/categories/keywords/{kw['id']}", json={"word": "coop"}).status_code == 409


def test_below_threshold_not_flagged(admin):
    giro = _account(admin, name="Giro NoFlag")
    a, b = _expense_cats(admin, 2)
    kw = admin.post(f"/api/categories/{a['id']}/keywords", json={"word": "denner"}).json()

    lines = "".join(f"0{i}.03.2026;-4,00;DENNER;Einkauf\n" for i in range(1, 7))  # 6 Zeilen
    rows = _preview_csv(admin, giro["id"], "Datum;Betrag;Empfaenger;Zweck\n" + lines, COLMAP)
    rows[0]["category_id"] = b["id"]  # nur 1 von 6 korrigiert (< 1/3)
    admin.post("/api/imports/commit", json={"account_id": giro["id"], "filename": "d.csv", "rows": rows})

    assert kw["id"] not in [f["id"] for f in admin.get("/api/categories/keywords/flagged").json()]


def test_amount_condition_rule(admin):
    giro = _account(admin, name="Giro Amt")
    a, _ = _expense_cats(admin, 2)
    # „sv" nur bei genau 5.00 -> Kategorie a
    r = admin.post(f"/api/categories/{a['id']}/keywords", json={"word": "sv", "amount_cents": 500})
    assert r.status_code == 201, r.text
    assert r.json()["amount_cents"] == 500

    csv = (
        "Datum;Betrag;Empfaenger;Zweck\n"
        "01.03.2026;-5,00;SV Restaurant;Mittag\n"    # 5.00 -> a
        "02.03.2026;-8,00;SV Restaurant;Produkt\n"   # anderer Betrag -> keine Regel
    )
    rows = _preview_csv(admin, giro["id"], csv, COLMAP)
    assert rows[0]["category_id"] == a["id"]
    assert rows[1]["category_id"] is None


def test_transfer_rule_and_target_guess(admin):
    giro = _account(admin, name="Giro TR")
    spar = _account(admin, name="Sparkonto TR", type="sparkonto",
                    identifiers=[{"kind": "text", "value": "Sparen"}])
    assert any(i["kind"] == "text" for i in spar["identifiers"])

    r = admin.post("/api/categories/transfer-keywords", json={"word": "uebertrag"})
    assert r.status_code == 201, r.text

    csv = (
        "Datum;Betrag;Empfaenger;Zweck\n"
        "01.03.2026;-100,00;Max;Uebertrag Sparen\n"       # -> Transfer, Ziel = Sparkonto
        "02.03.2026;-50,00;Max;Uebertrag woandershin\n"   # -> Transfer, kein Ziel erkannt
    )
    rows = _preview_csv(admin, giro["id"], csv, COLMAP)
    assert rows[0]["type"] == "transfer"
    assert rows[0]["to_account_id"] == spar["id"]
    assert rows[1]["type"] == "transfer"
    assert rows[1]["to_account_id"] is None


def test_transfer_keyword_conflicts_with_category_keyword(admin):
    a, _ = _expense_cats(admin, 2)
    admin.post(f"/api/categories/{a['id']}/keywords", json={"word": "doppelwort"})
    # gleiches Wort als Transfer-Regel -> Konflikt
    assert admin.post("/api/categories/transfer-keywords", json={"word": "doppelwort"}).status_code == 409


def test_no_retroactive_apply(admin):
    giro = _account(admin, name="Giro Retro")
    a, _ = _expense_cats(admin, 2)
    rows = _preview_csv(admin, giro["id"], "Datum;Betrag;Empfaenger;Zweck\n01.03.2026;-5,00;ALDI;Einkauf\n", COLMAP)
    assert rows[0]["category_id"] is None
    admin.post("/api/imports/commit", json={"account_id": giro["id"], "filename": "aldi.csv", "rows": rows})

    admin.post(f"/api/categories/{a['id']}/keywords", json={"word": "aldi"})  # erst danach angelegt

    txns = admin.get("/api/transactions").json()
    aldi = [t for t in txns if (t.get("payee") or "").upper() == "ALDI"]
    assert aldi and aldi[0]["category_id"] is None  # bestehende Buchung bleibt unkategorisiert