"""The Backups row on the System view (services/backup_health.py): quiet while
the backups keep up, a warning that says what is wrong when the newest dump is
more than a day old, the last one failed, or the bucket check found files
missing that no run has sent again since."""
from datetime import UTC, datetime, timedelta

import pytest

from backend.app.models import BackupRun
from backend.app.services import backup_health
from backend.app.services.backup_health import BackupFacts, verdict

NOW = datetime(2026, 3, 4, 12, 0, tzinfo=UTC)


def test_no_row_when_backups_are_not_set_up():
    assert verdict(BackupFacts(expected=False, offsite=False), NOW) is None


def test_a_dump_from_last_night_is_ok_and_says_its_age():
    part = verdict(BackupFacts(expected=True, offsite=True,
                               last_dump_at=NOW - timedelta(hours=9)), NOW)
    assert part["state"] == "ok"
    assert part["detail"] == "The newest database backup to the off-site bucket is 9 h old"


def test_a_dump_older_than_a_day_warns():
    part = verdict(BackupFacts(expected=True, offsite=False,
                               last_dump_at=NOW - timedelta(days=3)), NOW)
    assert part["state"] == "stale"
    assert part["detail"] == "The newest database backup on this server is 3 days old"


def test_no_dump_yet_warns():
    part = verdict(BackupFacts(expected=True, offsite=True), NOW)
    assert part["state"] == "stale"
    assert "No database backup has been taken to the off-site bucket yet" in part["detail"]


def test_a_failed_dump_warns_with_its_reason_beside_the_age():
    part = verdict(BackupFacts(expected=True, offsite=True,
                               last_dump_at=NOW - timedelta(hours=30),
                               last_dump_error="S3Error: HTTP 403"), NOW)
    assert part["state"] == "stale"
    assert "The last database backup failed: S3Error: HTTP 403" in part["detail"]
    assert "is 30 h old" in part["detail"]


def test_files_missing_from_the_bucket_warn():
    part = verdict(BackupFacts(expected=True, offsite=True,
                               last_dump_at=NOW - timedelta(hours=2), missing=1234), NOW)
    assert part["state"] == "stale"
    assert "found 1,234 file(s) missing from the bucket" in part["detail"]


# ── reading the facts ───────────────────────────────────────────────────────


def _run(db_sync, kind, status, at, **kw):
    row = BackupRun(kind=kind, status=status, triggered_by="nightly", started_at=at,
                    finished_at=at + timedelta(minutes=5), **kw)
    db_sync.add(row)
    db_sync.commit()
    return row


@pytest.fixture
def offsite(monkeypatch):
    monkeypatch.setattr("backend.app.services.backup_destination.describe",
                        lambda settings: {"configured": True})


@pytest.mark.integration
def test_the_facts_come_from_the_newest_runs(db_sync, offsite):
    now = datetime.now(UTC)
    _run(db_sync, "db", "ok", now - timedelta(days=2))
    newest = _run(db_sync, "db", "ok", now - timedelta(hours=3))
    _run(db_sync, "db", "running", now - timedelta(minutes=1))

    facts = backup_health.gather(db_sync)
    assert facts.expected and facts.offsite
    assert facts.last_dump_at == newest.finished_at
    assert facts.last_dump_error is None
    assert facts.missing == 0


@pytest.mark.integration
def test_the_newest_finished_dump_failing_is_reported(db_sync, offsite):
    now = datetime.now(UTC)
    _run(db_sync, "db", "ok", now - timedelta(days=2))
    _run(db_sync, "db", "error", now - timedelta(hours=3), error="DumpFailed: disk full")
    facts = backup_health.gather(db_sync)
    assert facts.last_dump_error == "DumpFailed: disk full"


@pytest.mark.integration
def test_missing_files_count_until_a_media_run_finishes_after_the_check(db_sync, offsite):
    now = datetime.now(UTC)
    check = _run(db_sync, "reconcile", "ok", now - timedelta(hours=5),
                 manifest={"listed": 10, "dropped": 3, "adopted": 0})
    _run(db_sync, "media", "ok", now - timedelta(days=1))
    assert backup_health.gather(db_sync).missing == 3

    _run(db_sync, "media", "ok", check.finished_at + timedelta(minutes=1))
    assert backup_health.gather(db_sync).missing == 0


@pytest.mark.integration
def test_nothing_is_expected_without_a_destination_or_the_nightly(db_sync, monkeypatch):
    monkeypatch.setattr("backend.app.services.backup_destination.describe",
                        lambda settings: {"configured": False})
    assert backup_health.gather(db_sync).expected is False


@pytest.mark.integration
async def test_the_system_view_lists_the_backups_row(client, offsite):
    body = await (await client.get("/api/system/health")).get_json()
    part = next(p for p in body["parts"] if p["key"] == "backup")
    assert part["state"] == "stale"
    assert part["detail"].startswith("No database backup has been taken")