from __future__ import annotations

import tempfile
import unittest
from decimal import Decimal
from pathlib import Path

from agent_integration.client import OpenAgentEvent
from agent_integration.service import OpenAgentService, SessionNotFoundError
from agent_integration.sessions import SQLiteSessionStore


class FakeAgentClient:
    def __init__(self):
        self.create_calls = []
        self.send_calls = []
        self.stream_calls = []
        self.run_calls = []

    def create_session(self, **kwargs):
        self.create_calls.append(kwargs)
        return {"session_id": "open_sess_123", "status": "active"}

    def send_message(self, session_id, message, **kwargs):
        self.send_calls.append((session_id, message, kwargs))
        return {"session_id": session_id, "run_id": "run_123", "status": "running"}

    def stream_message(self, session_id, message, **kwargs):
        self.stream_calls.append((session_id, message, kwargs))
        yield OpenAgentEvent(event="message.delta", data={"content": "你"})

    def get_run(self, session_id, run_id):
        self.run_calls.append(("get", session_id, run_id))
        return {"session_id": session_id, "run_id": run_id, "status": "completed"}

    def cancel_run(self, session_id, run_id):
        self.run_calls.append(("cancel", session_id, run_id))
        return {"session_id": session_id, "run_id": run_id, "status": "cancelling"}


class AgentServiceTests(unittest.TestCase):
    def test_session_is_created_once_and_persisted(self):
        with tempfile.TemporaryDirectory() as temp_dir:
            db_path = Path(temp_dir) / "sessions.sqlite3"
            client = FakeAgentClient()
            with SQLiteSessionStore(db_path) as store:
                service = OpenAgentService(client, store)  # type: ignore[arg-type]
                first = service.ensure_session(
                    "conversation-001",
                    external_subject_id="customer-001",
                    metadata={"source": "unittest"},
                )
                second = service.ensure_session("conversation-001")

            with SQLiteSessionStore(db_path) as reopened_store:
                persisted = reopened_store.get("conversation-001")

        self.assertEqual(first, second)
        self.assertEqual(first, persisted)
        self.assertEqual(len(client.create_calls), 1)
        session_key = client.create_calls[0]["idempotency_key"]
        self.assertTrue(session_key.startswith("sess_"))
        self.assertNotIn("conversation-001", session_key)

    def test_stable_message_id_produces_stable_idempotency_key(self):
        client = FakeAgentClient()
        with SQLiteSessionStore(":memory:") as store:
            service = OpenAgentService(client, store)  # type: ignore[arg-type]
            service.send_message("conversation-001", "first", message_id="upstream-message-001")
            service.send_message("conversation-001", "retry", message_id="upstream-message-001")

        self.assertEqual(len(client.create_calls), 1)
        first_key = client.send_calls[0][2]["idempotency_key"]
        second_key = client.send_calls[1][2]["idempotency_key"]
        self.assertEqual(first_key, second_key)
        self.assertTrue(first_key.startswith("msg_"))
        self.assertNotIn("upstream-message-001", first_key)

    def test_stream_get_cancel_and_forget_use_saved_session(self):
        client = FakeAgentClient()
        with SQLiteSessionStore(":memory:") as store:
            service = OpenAgentService(client, store)  # type: ignore[arg-type]
            events = list(
                service.stream_message(
                    "conversation-001",
                    "你好",
                    message_id="message-001",
                    include_trace=True,
                )
            )
            status = service.get_run("conversation-001", "run-001")
            cancelled = service.cancel_run("conversation-001", "run-001")
            deleted = service.forget_session("conversation-001")
            with self.assertRaises(SessionNotFoundError):
                service.get_session("conversation-001")

        self.assertEqual(events, [OpenAgentEvent(event="message.delta", data={"content": "你"})])
        self.assertEqual(status["status"], "completed")
        self.assertEqual(cancelled["status"], "cancelling")
        self.assertTrue(deleted)
        self.assertTrue(client.stream_calls[0][2]["include_trace"])
        self.assertEqual(
            client.run_calls,
            [
                ("get", "open_sess_123", "run-001"),
                ("cancel", "open_sess_123", "run-001"),
            ],
        )

    def test_unknown_conversation_fails_without_remote_call(self):
        client = FakeAgentClient()
        with SQLiteSessionStore(":memory:") as store:
            service = OpenAgentService(client, store)  # type: ignore[arg-type]
            with self.assertRaises(SessionNotFoundError):
                service.get_run("missing-conversation", "run-001")
        self.assertEqual(client.run_calls, [])

    def test_message_whitespace_is_preserved_and_metadata_is_strict_json(self):
        client = FakeAgentClient()
        with SQLiteSessionStore(":memory:") as store:
            service = OpenAgentService(client, store)  # type: ignore[arg-type]
            service.send_message("conversation-001", "  keep spacing  ", message_id="message-001")
            with self.assertRaises(ValueError):
                service.send_message(
                    "conversation-002",
                    "hello",
                    metadata={"not_json": Decimal("1.5")},
                )

        self.assertEqual(client.send_calls[0][1], "  keep spacing  ")
        self.assertEqual(len(client.create_calls), 1)


if __name__ == "__main__":
    unittest.main(verbosity=2)