"""Tests for chunk PDF file serving endpoint.

Coverage:
- GET /api/v1/chunks/{file_path}/pdf — success, 404, path traversal 400
"""
import os
import tempfile
import unittest
from unittest.mock import patch

from fastapi.testclient import TestClient

from app.main import app


class TestChunkServing(unittest.TestCase):
    """Test GET /api/v1/chunks/{file_path}/pdf endpoint."""

    def setUp(self):
        self.client = TestClient(app)

    def test_get_chunk_pdf_success(self):
        """Should serve chunk PDF file with 200 and application/pdf."""
        with tempfile.TemporaryDirectory() as tmp_dir:
            test_file = os.path.join(tmp_dir, "test_page_1.pdf")
            with open(test_file, "wb") as f:
                f.write(b"%PDF-1.4 fake content")

            with patch("app.core.config.get_settings") as mock_settings:
                mock_settings.return_value.document_chunk_path = tmp_dir
                response = self.client.get("/api/v1/chunks/test_page_1.pdf/pdf")

            self.assertEqual(response.status_code, 200)
            self.assertIn("application/pdf", response.headers["content-type"])

    def test_get_chunk_pdf_not_found(self):
        """Should return 404 for non-existent chunk file."""
        with patch("app.core.config.get_settings") as mock_settings:
            mock_settings.return_value.document_chunk_path = "/tmp/nonexistent_chunk_dir"
            response = self.client.get("/api/v1/chunks/nonexistent.pdf/pdf")

        self.assertEqual(response.status_code, 404)

    def test_get_chunk_pdf_path_traversal_double_dot(self):
        """Should reject path traversal with .. (404 due to Starlette normalization)."""
        with patch("app.core.config.get_settings") as mock_settings:
            mock_settings.return_value.document_chunk_path = "/tmp/fake_chunk_dir"
            response = self.client.get("/api/v1/chunks/../etc/passwd/pdf")

        self.assertIn(response.status_code, [400, 404])

    def test_get_chunk_pdf_path_traversal_symlink_escape(self):
        """Should reject resolved path escaping base directory (404 from normalization)."""
        with tempfile.TemporaryDirectory() as tmp_dir:
            with patch("app.core.config.get_settings") as mock_settings:
                mock_settings.return_value.document_chunk_path = tmp_dir
                response = self.client.get("/api/v1/chunks/../../etc/passwd/pdf")

            self.assertIn(response.status_code, [400, 404])

    def test_get_chunk_pdf_with_spaces_in_filename(self):
        """Should serve files with spaces in the filename."""
        with tempfile.TemporaryDirectory() as tmp_dir:
            test_file = os.path.join(tmp_dir, "NEC4 ACC_page_3.pdf")
            with open(test_file, "wb") as f:
                f.write(b"%PDF-1.4 fake content")

            with patch("app.core.config.get_settings") as mock_settings:
                mock_settings.return_value.document_chunk_path = tmp_dir
                response = self.client.get("/api/v1/chunks/NEC4 ACC_page_3.pdf/pdf")

            self.assertEqual(response.status_code, 200)
            self.assertIn("application/pdf", response.headers["content-type"])