#!/usr/bin/env python3
"""
Tests for the enforce_auth before_request hook in api/app.py.

The hook has two distinct behaviours depending on the auth store state:
  - users file exists and is POPULATED  → auth is enforced (unauthenticated → 401)
  - users file exists but is EMPTY      → 503 (auth not configured)
  - users file does not exist / unreadable → bypass (pre-auth compat mode)

These tests create real AuthManager instances pointing at tmp directories so
that list_users() and the file-readability check both behave exactly as they
do in production.
"""

import os
import sys
import json
import pytest
from pathlib import Path
from unittest.mock import patch

sys.path.insert(0, str(Path(__file__).parent.parent / 'api'))


@pytest.fixture
def flask_client():
    from app import app
    app.config['TESTING'] = True
    return app.test_client()


@pytest.fixture
def populated_auth_manager(tmp_path):
    """AuthManager whose users file contains at least one admin account."""
    from auth_manager import AuthManager
    data_dir = str(tmp_path / 'data')
    config_dir = str(tmp_path / 'config')
    os.makedirs(data_dir, exist_ok=True)
    os.makedirs(config_dir, exist_ok=True)
    mgr = AuthManager(data_dir=data_dir, config_dir=config_dir)
    # Create an admin so list_users() is non-empty
    ok = mgr.create_user('admin', 'AdminPass123!', 'admin')
    assert ok, 'Could not seed admin user for test'
    return mgr


@pytest.fixture
def empty_auth_manager(tmp_path):
    """AuthManager whose users file exists and is readable but contains no users."""
    from auth_manager import AuthManager
    data_dir = str(tmp_path / 'data')
    config_dir = str(tmp_path / 'config')
    os.makedirs(data_dir, exist_ok=True)
    os.makedirs(config_dir, exist_ok=True)
    mgr = AuthManager(data_dir=data_dir, config_dir=config_dir)
    # The constructor creates the file with '[]' (empty list). We do NOT add
    # any user, so list_users() returns [] but the file is readable.
    assert mgr.list_users() == [], 'Expected empty user list'
    return mgr


# ── populated store → auth enforced ──────────────────────────────────────────

def test_populated_auth_manager_unauthenticated_request_gets_401(
    flask_client, populated_auth_manager
):
    """When the auth store has users, unauthenticated API requests must get 401."""
    with patch('app.auth_manager', populated_auth_manager):
        r = flask_client.get('/api/status')
    assert r.status_code == 401
    data = json.loads(r.data)
    assert 'error' in data


def test_populated_auth_manager_401_body_says_not_authenticated(
    flask_client, populated_auth_manager
):
    """The 401 body must clearly indicate the session is missing."""
    with patch('app.auth_manager', populated_auth_manager):
        r = flask_client.get('/api/peers')
    assert r.status_code == 401
    data = json.loads(r.data)
    assert 'Not authenticated' in data.get('error', '')


def test_populated_auth_manager_non_api_path_bypasses_auth(
    flask_client, populated_auth_manager
):
    """Non-API paths like /health must always be public."""
    with patch('app.auth_manager', populated_auth_manager):
        r = flask_client.get('/health')
    assert r.status_code == 200


def test_populated_auth_manager_auth_namespace_bypasses_auth(
    flask_client, populated_auth_manager
):
    """The /api/auth/* namespace must always be accessible without a session."""
    with patch('app.auth_manager', populated_auth_manager):
        r = flask_client.get('/api/auth/me')
    # /api/auth/me may return 401 from the route itself (no session), but it
    # must NOT be blocked by enforce_auth; the enforce_auth hook must return None
    # for /api/auth/* paths.  The status must not be 503.
    assert r.status_code != 503


# ── empty store → 503 ────────────────────────────────────────────────────────

def test_empty_auth_manager_returns_503_for_api_requests(
    flask_client, empty_auth_manager
):
    """When the users file exists and is readable but empty, /api/* must get 503."""
    with patch('app.auth_manager', empty_auth_manager):
        r = flask_client.get('/api/status')
    assert r.status_code == 503
    data = json.loads(r.data)
    assert 'error' in data


def test_empty_auth_manager_503_body_mentions_configuration(
    flask_client, empty_auth_manager
):
    """The 503 error body must mention that auth is not configured."""
    with patch('app.auth_manager', empty_auth_manager):
        r = flask_client.get('/api/config')
    assert r.status_code == 503
    data = json.loads(r.data)
    error_text = data.get('error', '')
    assert 'not configured' in error_text.lower() or 'Authentication' in error_text


def test_empty_auth_manager_non_api_path_bypasses_503(
    flask_client, empty_auth_manager
):
    """Even with an empty auth store, /health must remain accessible."""
    with patch('app.auth_manager', empty_auth_manager):
        r = flask_client.get('/health')
    assert r.status_code == 200


if __name__ == '__main__':
    pytest.main([__file__, '-v'])