import asyncio
import json
import unittest
from concurrent.futures import Future

from app.api.producer import MockMessageProducer
from app.api.server import IngestionAPIServer


def payload():
    return dict(raw_id="delivery-test", device_id="123", caller_num="+19875551234",
                svc="4G_DATA", rat=6, lac="1", ci="2", up_bytes=10,
                down_bytes=20, epoch_start=1726070000, epoch_end=1726070300)


class PendingProducer(MockMessageProducer):
    def __init__(self):
        super().__init__()
        self.pending = []

    def produce(self, topic, key, value):
        future = Future()
        self.pending.append(future)
        return future


class Writer:
    def __init__(self):
        self.data = b""

    def write(self, value):
        self.data += value

    async def drain(self):
        pass


class TestAcknowledgedAPI(unittest.IsolatedAsyncioTestCase):
    async def test_response_waits_for_delivery_and_bounds_outstanding(self):
        producer = PendingProducer()
        server = IngestionAPIServer(producer=producer, queue_max_size=1)
        writer = Writer()
        task = asyncio.create_task(server._handle_raw_cdr_ingestion(writer, json.dumps(payload()).encode()))
        await asyncio.sleep(0.02)
        self.assertEqual(writer.data, b"", "202 must await the broker")
        other = Writer()
        await server._handle_raw_cdr_ingestion(other, json.dumps(payload()).encode())
        self.assertIn(b"429", other.data)
        producer.pending[0].set_result(None)
        await task
        self.assertIn(b"202", writer.data)

    async def test_missing_fields_wrong_types_and_utf8_return_400(self):
        server = IngestionAPIServer(producer=MockMessageProducer())
        for body in (b"{}", b"\xff", json.dumps(payload() | {"raw_id": 42}).encode(),
                     json.dumps(payload() | {"rat": True}).encode()):
            with self.subTest(body=body):
                writer = Writer()
                await server._handle_raw_cdr_ingestion(writer, body)
                self.assertIn(b"400", writer.data)

    async def test_failed_delivery_returns_503_and_next_request_recovers(self):
        producer = MockMessageProducer()
        server = IngestionAPIServer(producer=producer)
        producer.set_healthy(False)
        writer = Writer()
        await server._handle_raw_cdr_ingestion(writer, json.dumps(payload()).encode())
        self.assertIn(b"503", writer.data)
        producer.set_healthy(True)
        writer = Writer()
        await server._handle_raw_cdr_ingestion(writer, json.dumps(payload()).encode())
        self.assertIn(b"202", writer.data)