"""Raw request limits apply before JSON validation and across body chunks."""

import asyncio
import unittest
from unittest.mock import patch

from fastapi.testclient import TestClient

import app as server
from request_limits import RequestSizeLimitMiddleware


class RequestLimitTests(unittest.TestCase):
    def test_oversized_json_is_rejected_before_inference(self):
        with patch.object(server.engine, "analyze_locked") as analyze:
            for path in ["/api/analyze", "/api/jobs"]:
                response = TestClient(server.app).post(path, json={
                    "task": "pii", "text": "x" * (12 * 1024 * 1024),
                })
                self.assertEqual(response.status_code, 413)
                self.assertEqual(response.json()["detail"], "Request is too large. Use fewer or smaller media files, or shorten the text.")
                self.assertEqual(response.headers["Cache-Control"], "no-store, max-age=0")
        analyze.assert_not_called()

    def test_chunked_body_cannot_bypass_the_limit(self):
        async def exercise():
            messages = iter([
                {"type": "http.request", "body": b"12345", "more_body": True},
                {"type": "http.request", "body": b"67890", "more_body": True},
            ])
            sent = []

            async def receive():
                return next(messages)

            async def send(message):
                sent.append(message)

            async def downstream(scope, receive, send):
                self.fail("An oversized request must not reach the framework")

            await RequestSizeLimitMiddleware(downstream, max_bytes=8)(
                {"type": "http", "path": "/api/analyze"}, receive, send,
            )
            self.assertEqual(sent[0]["status"], 413)

        asyncio.run(exercise())


if __name__ == "__main__":
    unittest.main()