"""
Integration tests for authorization endpoint flow.

Tests the complete authorization endpoint behavior including parameter validation,
client metadata fetching, consent form rendering, and code generation.
"""

import tempfile
from pathlib import Path
from unittest.mock import AsyncMock, Mock, patch

import pytest
from fastapi.testclient import TestClient


@pytest.fixture
def auth_app(monkeypatch, tmp_path):
    """Create app for authorization testing."""
    db_path = tmp_path / "test.db"

    monkeypatch.setenv("GONDULF_SECRET_KEY", "a" * 32)
    monkeypatch.setenv("GONDULF_BASE_URL", "https://auth.example.com")
    monkeypatch.setenv("GONDULF_DATABASE_URL", f"sqlite:///{db_path}")
    monkeypatch.setenv("GONDULF_DEBUG", "true")

    from gondulf.main import app
    return app


@pytest.fixture
def auth_client(auth_app):
    """Create test client for authorization tests."""
    with TestClient(auth_app) as client:
        yield client


@pytest.fixture
def mock_happ_fetch():
    """Mock h-app parser to avoid network calls."""
    from gondulf.services.happ_parser import ClientMetadata

    metadata = ClientMetadata(
        name="Test Application",
        url="https://app.example.com",
        logo="https://app.example.com/logo.png"
    )

    with patch('gondulf.services.happ_parser.HAppParser.fetch_and_parse', new_callable=AsyncMock) as mock:
        mock.return_value = metadata
        yield mock


class TestAuthorizationEndpointValidation:
    """Tests for authorization endpoint parameter validation."""

    def test_missing_client_id_returns_error(self, auth_client):
        """Test that missing client_id returns 400 error."""
        response = auth_client.get("/authorize", params={
            "redirect_uri": "https://app.example.com/callback",
            "response_type": "code",
            "state": "test123",
        })

        assert response.status_code == 400
        assert "client_id" in response.text.lower()

    def test_missing_redirect_uri_returns_error(self, auth_client):
        """Test that missing redirect_uri returns 400 error."""
        response = auth_client.get("/authorize", params={
            "client_id": "https://app.example.com",
            "response_type": "code",
            "state": "test123",
        })

        assert response.status_code == 400
        assert "redirect_uri" in response.text.lower()

    def test_http_client_id_rejected(self, auth_client):
        """Test that HTTP client_id (non-HTTPS) is rejected."""
        response = auth_client.get("/authorize", params={
            "client_id": "http://app.example.com",  # HTTP not allowed
            "redirect_uri": "https://app.example.com/callback",
            "response_type": "code",
            "state": "test123",
        })

        assert response.status_code == 400
        assert "https" in response.text.lower()

    def test_mismatched_redirect_uri_rejected(self, auth_client):
        """Test that redirect_uri not matching client_id domain is rejected."""
        response = auth_client.get("/authorize", params={
            "client_id": "https://app.example.com",
            "redirect_uri": "https://evil.example.com/callback",  # Different domain
            "response_type": "code",
            "state": "test123",
        })

        assert response.status_code == 400
        assert "redirect_uri" in response.text.lower()


class TestAuthorizationEndpointRedirectErrors:
    """Tests for errors that redirect back to the client."""

    @pytest.fixture
    def valid_params(self):
        """Valid base authorization parameters."""
        return {
            "client_id": "https://app.example.com",
            "redirect_uri": "https://app.example.com/callback",
            "state": "test123",
        }

    def test_invalid_response_type_redirects_with_error(self, auth_client, valid_params, mock_happ_fetch):
        """Test invalid response_type redirects with error parameter."""
        params = valid_params.copy()
        params["response_type"] = "token"  # Invalid - only "code" is supported

        response = auth_client.get("/authorize", params=params, follow_redirects=False)

        assert response.status_code == 302
        location = response.headers["location"]
        assert "error=unsupported_response_type" in location
        assert "state=test123" in location

    def test_missing_code_challenge_redirects_with_error(self, auth_client, valid_params, mock_happ_fetch):
        """Test missing PKCE code_challenge redirects with error."""
        params = valid_params.copy()
        params["response_type"] = "code"
        params["me"] = "https://user.example.com"
        # Missing code_challenge

        response = auth_client.get("/authorize", params=params, follow_redirects=False)

        assert response.status_code == 302
        location = response.headers["location"]
        assert "error=invalid_request" in location
        assert "code_challenge" in location.lower()

    def test_invalid_code_challenge_method_redirects_with_error(self, auth_client, valid_params, mock_happ_fetch):
        """Test invalid code_challenge_method redirects with error."""
        params = valid_params.copy()
        params["response_type"] = "code"
        params["me"] = "https://user.example.com"
        params["code_challenge"] = "abc123"
        params["code_challenge_method"] = "plain"  # Invalid - only S256 supported

        response = auth_client.get("/authorize", params=params, follow_redirects=False)

        assert response.status_code == 302
        location = response.headers["location"]
        assert "error=invalid_request" in location
        assert "S256" in location

    def test_missing_me_parameter_redirects_with_error(self, auth_client, valid_params, mock_happ_fetch):
        """Test missing me parameter redirects with error."""
        params = valid_params.copy()
        params["response_type"] = "code"
        params["code_challenge"] = "abc123"
        params["code_challenge_method"] = "S256"
        # Missing me parameter

        response = auth_client.get("/authorize", params=params, follow_redirects=False)

        assert response.status_code == 302
        location = response.headers["location"]
        assert "error=invalid_request" in location
        assert "me" in location.lower()

    def test_invalid_me_url_redirects_with_error(self, auth_client, valid_params, mock_happ_fetch):
        """Test invalid me URL redirects with error."""
        params = valid_params.copy()
        params["response_type"] = "code"
        params["code_challenge"] = "abc123"
        params["code_challenge_method"] = "S256"
        params["me"] = "not-a-valid-url"

        response = auth_client.get("/authorize", params=params, follow_redirects=False)

        assert response.status_code == 302
        location = response.headers["location"]
        assert "error=invalid_request" in location


class TestAuthorizationConsentPage:
    """Tests for the consent page rendering."""

    @pytest.fixture
    def complete_params(self):
        """Complete valid authorization parameters."""
        return {
            "client_id": "https://app.example.com",
            "redirect_uri": "https://app.example.com/callback",
            "response_type": "code",
            "state": "test123",
            "code_challenge": "E9Melhoa2OwvFrEMTJguCHaoeK1t8URWbuGJSstw-cM",
            "code_challenge_method": "S256",
            "me": "https://user.example.com",
        }

    def test_valid_request_shows_consent_page(self, auth_client, complete_params, mock_happ_fetch):
        """Test valid authorization request shows consent page."""
        response = auth_client.get("/authorize", params=complete_params)

        assert response.status_code == 200
        assert "text/html" in response.headers["content-type"]
        # Page should contain client information
        assert "app.example.com" in response.text or "Test Application" in response.text

    def test_consent_page_contains_required_fields(self, auth_client, complete_params, mock_happ_fetch):
        """Test consent page contains all required form fields."""
        response = auth_client.get("/authorize", params=complete_params)

        assert response.status_code == 200
        # Check for hidden form fields that will be POSTed
        assert "client_id" in response.text
        assert "redirect_uri" in response.text
        assert "code_challenge" in response.text

    def test_consent_page_displays_client_metadata(self, auth_client, complete_params, mock_happ_fetch):
        """Test consent page displays client h-app metadata."""
        response = auth_client.get("/authorize", params=complete_params)

        assert response.status_code == 200
        # Should show client name from h-app
        assert "Test Application" in response.text or "app.example.com" in response.text

    def test_consent_page_preserves_state(self, auth_client, complete_params, mock_happ_fetch):
        """Test consent page preserves state parameter."""
        response = auth_client.get("/authorize", params=complete_params)

        assert response.status_code == 200
        assert "test123" in response.text


class TestAuthorizationConsentSubmission:
    """Tests for consent form submission."""

    @pytest.fixture
    def consent_form_data(self):
        """Valid consent form data."""
        return {
            "client_id": "https://app.example.com",
            "redirect_uri": "https://app.example.com/callback",
            "state": "test123",
            "code_challenge": "E9Melhoa2OwvFrEMTJguCHaoeK1t8URWbuGJSstw-cM",
            "code_challenge_method": "S256",
            "me": "https://user.example.com",
            "scope": "",
        }

    def test_consent_submission_redirects_with_code(self, auth_client, consent_form_data):
        """Test consent submission redirects to client with authorization code."""
        response = auth_client.post(
            "/authorize/consent",
            data=consent_form_data,
            follow_redirects=False
        )

        assert response.status_code == 302
        location = response.headers["location"]
        assert location.startswith("https://app.example.com/callback")
        assert "code=" in location
        assert "state=test123" in location

    def test_consent_submission_generates_unique_codes(self, auth_client, consent_form_data):
        """Test each consent generates a unique authorization code."""
        # First submission
        response1 = auth_client.post(
            "/authorize/consent",
            data=consent_form_data,
            follow_redirects=False
        )
        location1 = response1.headers["location"]

        # Second submission
        response2 = auth_client.post(
            "/authorize/consent",
            data=consent_form_data,
            follow_redirects=False
        )
        location2 = response2.headers["location"]

        # Extract codes
        from tests.conftest import extract_code_from_redirect
        code1 = extract_code_from_redirect(location1)
        code2 = extract_code_from_redirect(location2)

        assert code1 != code2

    def test_authorization_code_stored_for_exchange(self, auth_client, consent_form_data):
        """Test authorization code is stored for later token exchange."""
        response = auth_client.post(
            "/authorize/consent",
            data=consent_form_data,
            follow_redirects=False
        )

        from tests.conftest import extract_code_from_redirect
        code = extract_code_from_redirect(response.headers["location"])

        # Code should be non-empty and URL-safe
        assert code is not None
        assert len(code) > 20  # Should be a substantial code


class TestAuthorizationSecurityHeaders:
    """Tests for security headers on authorization endpoints."""

    def test_authorization_page_has_security_headers(self, auth_client, mock_happ_fetch):
        """Test authorization page includes security headers."""
        params = {
            "client_id": "https://app.example.com",
            "redirect_uri": "https://app.example.com/callback",
            "response_type": "code",
            "state": "test123",
            "code_challenge": "abc123",
            "code_challenge_method": "S256",
            "me": "https://user.example.com",
        }
        response = auth_client.get("/authorize", params=params)

        assert "X-Frame-Options" in response.headers
        assert "X-Content-Type-Options" in response.headers
        assert response.headers["X-Frame-Options"] == "DENY"

    def test_error_pages_have_security_headers(self, auth_client):
        """Test error pages include security headers."""
        # Request without client_id should return error page
        response = auth_client.get("/authorize", params={
            "redirect_uri": "https://app.example.com/callback"
        })

        assert response.status_code == 400
        assert "X-Frame-Options" in response.headers
        assert "X-Content-Type-Options" in response.headers