from __future__ import annotations

import re

import pytest


def _mock_checks(monkeypatch, **overrides):
    payloads = {
        "db": {"status": "ok", "latency_ms": 1.0},
        "cache": {"status": "ok", "latency_ms": 1.0},
        "celery": {"status": "ok"},
        "backup": {"status": "ok"},
    }
    payloads.update(overrides)

    monkeypatch.setattr("apps.health.views.check_db", lambda: payloads["db"])
    monkeypatch.setattr("apps.health.views.check_cache", lambda: payloads["cache"])
    monkeypatch.setattr("apps.health.views.check_celery", lambda: payloads["celery"])
    monkeypatch.setattr("apps.health.views.check_backup", lambda: payloads["backup"])


@pytest.mark.django_db
def test_healthy(client, monkeypatch):
    _mock_checks(monkeypatch)

    response = client.get("/health/")

    assert response.status_code == 200
    assert response.json()["status"] == "ok"


@pytest.mark.django_db
def test_degraded_celery(client, monkeypatch):
    _mock_checks(monkeypatch, celery={"status": "fail", "detail": "broker down"})

    response = client.get("/health/")

    assert response.status_code == 200
    assert response.json()["status"] == "degraded"


@pytest.mark.django_db
def test_degraded_backup(client, monkeypatch):
    _mock_checks(monkeypatch, backup={"status": "fail", "detail": "backup missing"})

    response = client.get("/health/")

    assert response.status_code == 200
    assert response.json()["status"] == "degraded"


@pytest.mark.django_db
def test_unhealthy_db(client, monkeypatch):
    _mock_checks(monkeypatch, db={"status": "fail", "detail": "db down"})

    response = client.get("/health/")

    assert response.status_code == 503
    assert response.json()["status"] == "unhealthy"


@pytest.mark.django_db
def test_unhealthy_cache(client, monkeypatch):
    _mock_checks(monkeypatch, cache={"status": "fail", "detail": "cache down"})

    response = client.get("/health/")

    assert response.status_code == 503
    assert response.json()["status"] == "unhealthy"


@pytest.mark.django_db
def test_response_shape(client, monkeypatch):
    _mock_checks(monkeypatch)

    payload = client.get("/health/").json()

    assert set(payload) == {"status", "version", "checks", "timestamp"}
    assert set(payload["version"]) == {"git_sha", "build"}
    assert set(payload["checks"]) == {"db", "cache", "celery", "backup"}
    assert re.fullmatch(r"\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}Z", payload["timestamp"])


@pytest.mark.django_db
def test_version_fields(client, monkeypatch):
    _mock_checks(monkeypatch)
    monkeypatch.setenv("GIT_SHA", "59cc1c4")
    monkeypatch.setenv("BUILD_ID", "build-20260306-59cc1c4")

    payload = client.get("/health/").json()

    assert payload["version"]["git_sha"] == "59cc1c4"
    assert payload["version"]["build"] == "build-20260306-59cc1c4"


@pytest.mark.django_db
def test_no_cache_headers(client, monkeypatch):
    _mock_checks(monkeypatch)

    response = client.get("/health/")

    assert "no-cache" in response["Cache-Control"]