import importlib
import os

import pytest
from fastapi.testclient import TestClient


@pytest.fixture
def client(tmp_path):
    os.environ["DB_PATH"] = str(tmp_path / "test.db")
    os.environ["SYNC_TOKEN"] = "geheim"
    os.environ["FILES_DIR"] = str(tmp_path / "files")
    from app import config, db, files, main
    importlib.reload(config)
    importlib.reload(db)
    importlib.reload(files)
    importlib.reload(main)
    with TestClient(main.app) as c:
        yield c


AUTH = {"Authorization": "Bearer geheim"}


def sync(client, since=0, **collections):
    body = {"since": since, **collections}
    r = client.post("/api/sync", json=body, headers=AUTH)
    assert r.status_code == 200, r.text
    return r.json()


def test_health_ohne_token(client):
    assert client.get("/api/health").json() == {"ok": True}


def test_falscher_token(client):
    assert client.post("/api/sync", json={}).status_code == 401
    assert client.post("/api/sync", json={}, headers={"Authorization": "Bearer falsch"}).status_code == 401
    assert client.get("/api/events").status_code == 401


def test_push_und_pull(client):
    a = sync(client, events=[{"id": "e1", "updated": "2026-09-19T10:00:00.000Z", "title": "Zahnarzt"}])
    assert a["cursor"] == 1
    assert [e["id"] for e in a["events"]] == ["e1"]

    # Anderes Gerät ohne Stand bekommt alles
    b = sync(client)
    assert [e["title"] for e in b["events"]] == ["Zahnarzt"]
    assert b["cursor"] == 1

    # Mit aktuellem Stand kommt nichts Neues
    c = sync(client, since=1)
    assert c["events"] == [] and c["cursor"] == 1


def test_neuester_gewinnt(client):
    sync(client, todos=[{"id": "t1", "updated": "2026-09-19T10:00:00.000Z", "title": "alt"}])
    sync(client, todos=[{"id": "t1", "updated": "2026-09-19T09:00:00.000Z", "title": "älter"}])
    assert client.get("/api/todos", headers=AUTH).json()[0]["title"] == "alt"
    r = sync(client, since=0, todos=[{"id": "t1", "updated": "2026-09-19T11:00:00.000Z", "title": "neu"}])
    assert r["todos"][0]["title"] == "neu"
    assert r["cursor"] == 2


def test_abgelehnte_aenderung_bekommt_serverstand(client):
    sync(client, todos=[{"id": "t1", "updated": "2026-09-19T10:00:00.000Z", "title": "server"}])
    r = sync(client, since=1, todos=[{"id": "t1", "updated": "2026-09-19T09:00:00.000Z", "title": "client"}])
    assert [t["title"] for t in r["todos"]] == ["server"]
    assert r["cursor"] == 1


def test_tombstone(client):
    sync(client, notes=[{"id": "Plan.md", "updated": "2026-09-19T10:00:00.000Z", "content": "x"}])
    r = sync(client, since=1, notes=[{"id": "Plan.md", "updated": "2026-09-19T10:05:00.000Z", "deleted": True}])
    assert r["notes"][0]["deleted"] is True
    assert client.get("/api/notes", headers=AUTH).json() == []
    # Ein verspäteter älterer Stand belebt die Notiz nicht wieder
    sync(client, notes=[{"id": "Plan.md", "updated": "2026-09-19T10:01:00.000Z", "content": "y"}])
    assert client.get("/api/notes", headers=AUTH).json() == []


def test_ordner_laufen_mit(client):
    r = sync(client, folders=[{"id": "Projekte/Alt", "updated": "2026-09-19T10:00:00.000Z", "deleted": False}])
    assert r["folders"][0]["id"] == "Projekte/Alt"
    r = sync(client, since=1, folders=[{"id": "Projekte/Alt", "updated": "2026-09-19T10:05:00.000Z", "deleted": True}])
    assert r["folders"][0]["deleted"] is True


def test_seit_cursor_liefert_nur_neues(client):
    sync(client, events=[{"id": "e1", "updated": "2026-09-19T10:00:00.000Z", "title": "a"}])
    sync(client, events=[{"id": "e2", "updated": "2026-09-19T10:00:00.000Z", "title": "b"}])
    r = sync(client, since=1)
    assert [e["id"] for e in r["events"]] == ["e2"]


def test_dateien_nur_auf_anfrage(client):
    sync(client, files=[{"id": "-home-x/s1.jsonl", "updated": "2026-09-22T10:00:00.000Z", "content": "zeile\n"}])
    # Handy und Extension fragen ohne files: nichts davon in der Antwort
    r = sync(client, events=[], todos=[], notes=[], folders=[])
    assert "files" not in r and r["events"] == []
    assert "files" not in sync(client)
    # Nur Dateien angefragt: nur der Steckbrief zurück, kein Inhalt
    r = sync(client, files=[])
    assert r["files"] == [{"id": "-home-x/s1.jsonl", "updated": "2026-09-22T10:00:00.000Z", "size": 6}] and "events" not in r
    assert r["cursor"] == 1


def test_dateien_inhalt_auf_platte_und_anhaengen(client, tmp_path):
    import hashlib
    sync(client, files=[{"id": "p/s.jsonl", "updated": "2026-09-22T10:00:00.000Z", "content": "a\n"}])
    assert (tmp_path / "files" / "p" / "s.jsonl").read_bytes() == b"a\n"
    # Anhang mit passendem Stand
    base = {"size": 2, "hash": hashlib.sha256(b"a\n").hexdigest()}
    r = sync(client, files=[{"id": "p/s.jsonl", "updated": "2026-09-22T11:00:00.000Z", "base": base, "append": "b\n"}])
    assert (tmp_path / "files" / "p" / "s.jsonl").read_bytes() == b"a\nb\n"
    assert r["files"][-1]["size"] == 4
    # Anhang mit falschem Stand: abgelehnt, Server-Stand samt Hash kommt zurück
    r = sync(client, since=99, files=[{"id": "p/s.jsonl", "updated": "2026-09-22T12:00:00.000Z", "base": base, "append": "c\n"}])
    assert r["files"] == [{"id": "p/s.jsonl", "updated": "2026-09-22T11:00:00.000Z", "size": 4, "hash": hashlib.sha256(b"a\nb\n").hexdigest()}]
    assert (tmp_path / "files" / "p" / "s.jsonl").read_bytes() == b"a\nb\n"
    # Inhalt holen: ganz, oder nur den Rest ab bekanntem Stand
    r = client.get("/api/files/p/s.jsonl", headers=AUTH)
    assert r.content == b"a\nb\n" and r.headers["X-From"] == "0" and r.headers["X-Size"] == "4"
    r = client.get("/api/files/p/s.jsonl", params={"from": 2, "hash": base["hash"]}, headers=AUTH)
    assert r.content == b"b\n" and r.headers["X-From"] == "2"
    r = client.get("/api/files/p/s.jsonl", params={"from": 2, "hash": "falsch"}, headers=AUTH)
    assert r.content == b"a\nb\n" and r.headers["X-From"] == "0"
    # Löschen räumt die Platte, Tombstone bleibt, Inhalt weg
    sync(client, files=[{"id": "p/s.jsonl", "updated": "2026-09-22T13:00:00.000Z", "deleted": True}])
    assert not (tmp_path / "files" / "p" / "s.jsonl").exists()
    assert client.get("/api/files/p/s.jsonl", headers=AUTH).status_code == 404
    assert sync(client, files=[])["files"][-1]["deleted"] is True


def test_dateien_aus_datenbank_auf_platte(client, tmp_path):
    import json
    from app import db, files
    # Alter Stand: Inhalt in der Datenbank
    with db.connect(write=True) as conn:
        conn.execute("INSERT INTO items VALUES ('files', 'alt/s.jsonl', '2026-09-01T00:00:00.000Z', 0, ?, 1)",
                     (json.dumps({"id": "alt/s.jsonl", "updated": "2026-09-01T00:00:00.000Z", "content": "alt\n"}),))
    with db.connect(write=True) as conn:
        assert files.migrate(conn) == 1
        assert files.migrate(conn) == 0
    assert (tmp_path / "files" / "alt" / "s.jsonl").read_bytes() == b"alt\n"
    assert sync(client, files=[])["files"] == [{"id": "alt/s.jsonl", "updated": "2026-09-01T00:00:00.000Z", "size": 4}]