# Copyright (c) Microsoft. All rights reserved.

from __future__ import annotations

import threading
import time
from typing import Any, List, Optional, Union

import agentops
import pytest
import pytest_asyncio
import uvicorn
from agentops.sdk.core import TraceContext
from fastapi import FastAPI, Request
from opentelemetry.proto.collector.trace.v1.trace_service_pb2 import (
    ExportTraceServiceRequest,
    ExportTraceServiceResponse,
)
from opentelemetry.sdk.trace import ReadableSpan
from opentelemetry.trace.status import StatusCode
from portpicker import pick_unused_port

from agentlightning.store.base import LightningStore, LightningStoreCapabilities
from agentlightning.tracer.agentops import AgentOpsTracer
from agentlightning.types import Span, TraceStatus
from agentlightning.utils import otlp

pytestmark = [pytest.mark.agentops]


@pytest_asyncio.fixture
async def agentops_tracer():
    tracer = AgentOpsTracer()
    with tracer.lifespan():
        async with tracer.trace_context():
            yield tracer


class MockOTLPService:
    """A mock OTLP server to capture trace export requests for testing purposes."""

    def __init__(self) -> None:
        self.received: List[ExportTraceServiceRequest] = []

    def start_service(self) -> int:
        app = FastAPI()

        @app.post("/v1/traces")
        async def _export_traces(request: Request):  # type: ignore
            async def capture(message: ExportTraceServiceRequest) -> None:
                self.received.append(message)

            return await otlp.handle_otlp_export(
                request,
                ExportTraceServiceRequest,
                ExportTraceServiceResponse,
                capture,
                signal_name="traces",
            )

        port = pick_unused_port()
        config = uvicorn.Config(app, host="127.0.0.1", port=port, log_level="error")
        self.server = uvicorn.Server(config)
        self.thread = threading.Thread(target=self.server.run, daemon=True)
        self.thread.start()
        timeout = time.time() + 5
        while not getattr(self.server, "started", False):
            if time.time() > timeout:
                raise RuntimeError("OTLP test server failed to start")
            if not self.thread.is_alive():
                raise RuntimeError("OTLP test server thread exited before startup")
            time.sleep(0.01)

        return port

    def stop_service(self) -> None:
        self.server.should_exit = True
        self.thread.join(timeout=5)

    def get_traces(self) -> List[ExportTraceServiceRequest]:
        return self.received


class MockLightningStore(LightningStore):
    """A minimal stub-only LightningStore, only implements methods likely used in tests."""

    def __init__(self, server_port: int = 80) -> None:
        super().__init__()
        self.otlp_traces = False
        self.server_port = server_port

    def enable_otlp_traces(self) -> None:
        self.otlp_traces = True

    async def add_otel_span(
        self,
        rollout_id: str,
        attempt_id: str,
        readable_span: ReadableSpan,
        sequence_id: int | None = None,
    ) -> Span:
        if sequence_id is None:
            sequence_id = 0

        span = Span.from_opentelemetry(
            readable_span, rollout_id=rollout_id, attempt_id=attempt_id, sequence_id=sequence_id
        )
        return span

    @property
    def capabilities(self) -> LightningStoreCapabilities:
        """Return the capabilities of the store."""
        return LightningStoreCapabilities(
            async_safe=False,
            thread_safe=False,
            zero_copy=False,
            otlp_traces=self.otlp_traces,
        )

    def otlp_traces_endpoint(self) -> str:
        return f"http://127.0.0.1:{self.server_port}/v1/traces"


def _func_with_exception():
    """Function that always raises an exception to test error tracing."""
    raise ValueError("This is a test exception")


def _func_without_exception():
    """Function that always executed successfully to test success tracing."""
    pass


def test_agentops_tracer_create_span(agentops_tracer: AgentOpsTracer) -> None:
    status = TraceStatus(status_code="ERROR", description="agentops")

    span = agentops_tracer.create_span(
        "agentops-span",
        attributes={"foo": "bar"},
        status=status,
        timestamp=42_000.0,
    )

    assert span.name == "agentops-span"
    assert span.attributes["foo"] == "bar"
    assert span.status.status_code == "ERROR"
    assert span.status.description == "agentops"
    assert span.start_time is not None
    assert span.end_time is not None


def test_agentops_tracer_operation_context_records_exception(agentops_tracer: AgentOpsTracer) -> None:
    with pytest.raises(ValueError):
        with agentops_tracer.operation_context("agentops-op", attributes={"foo": "bar"}) as ctx:
            raise ValueError("agentops boom")

    recorded_span = ctx.get_recorded_span()  # type: ignore
    assert recorded_span.name == "agentops-op"
    assert recorded_span.status.status_code == "ERROR"
    assert recorded_span.status.description is not None
    assert "agentops boom" in recorded_span.status.description


@pytest.mark.asyncio
@pytest.mark.parametrize("with_exception", [True, False])
async def test_trace_error_status_from_instance(with_exception: bool):
    import agentlightning

    agentlightning.setup_logging("DEBUG")
    captured_state = {}
    old_end_trace = agentops.end_trace

    def custom_end_trace(
        trace_context: Optional[TraceContext] = None, end_state: Union[Any, StatusCode, str] = None
    ) -> None:
        captured_state["state"] = end_state
        return old_end_trace(trace_context, end_state=end_state)

    agentops.end_trace = custom_end_trace

    tracer = AgentOpsTracer()
    with tracer.lifespan():
        try:
            if with_exception:
                with pytest.raises(ValueError):
                    async with tracer.trace_context():
                        _func_with_exception()
                assert captured_state["state"] == StatusCode.ERROR
            else:
                async with tracer.trace_context():
                    _func_without_exception()
                assert captured_state["state"] == StatusCode.OK
        finally:
            agentops.end_trace = old_end_trace


@pytest.mark.asyncio
async def test_agentops_trace_without_store():
    tracer = AgentOpsTracer()

    with tracer.lifespan():
        # Using AgentOpsTracer to trace a function without providing a store, rollout_id, or attempt_id.
        async with tracer.trace_context(name="agentops_test"):
            _func_without_exception()
        spans = tracer.get_last_trace()
        assert len(spans) > 0


@pytest.mark.asyncio
async def test_agentops_trace_with_store_disable():
    tracer = AgentOpsTracer()

    with tracer.lifespan():
        # Using AgentOpsTracer to trace a function with providing a store which disabled native otlp exporter, rollout_id, and attempt_id.
        store = MockLightningStore()
        async with tracer.trace_context(
            name="agentops_test", store=store, rollout_id="test_rollout_id", attempt_id="test_attempt_id"
        ):
            _func_without_exception()
        spans = tracer.get_last_trace()
        assert len(spans) > 0


@pytest.mark.asyncio
async def test_agentops_trace_with_store_enable():
    mock_service = MockOTLPService()
    port = mock_service.start_service()

    tracer = AgentOpsTracer()

    with tracer.lifespan():
        try:
            # Using AgentOpsTracer to trace a function with providing a store which disabled native otlp exporter, rollout_id, and attempt_id.
            store = MockLightningStore(port)
            async with tracer.trace_context(
                name="agentops_test", store=store, rollout_id="test_rollout_id", attempt_id="test_attempt_id"
            ):
                _func_without_exception()
            spans = tracer.get_last_trace()
            assert len(spans) > 0
        finally:
            mock_service.stop_service()