import os
from collections.abc import AsyncIterator
from contextlib import asynccontextmanager
from pathlib import Path
from types import SimpleNamespace

import pytest
from fastapi.testclient import TestClient

os.environ["DATABASE_URL"] = "sqlite:///./data/test_gargi_ai.db"
os.environ["GEMINI_API_KEY"] = "test-key"

from gargi_ai.config import get_settings  # noqa: E402
from gargi_ai.database import Base, engine  # noqa: E402
from gargi_ai.main import app  # noqa: E402
from gargi_ai.providers import LiveProvider, LLMProvider, TTSProvider  # noqa: E402
from gargi_ai.schemas import QuizQuestion, TeachingPayload, WhiteboardBlock  # noqa: E402


class FakeLLM(LLMProvider):
    async def stream_explanation(self, prompt: str) -> AsyncIterator[str]:
        yield "Gravity "
        yield "pulls objects together."

    async def generate_artifact(self, prompt: str) -> TeachingPayload:
        return TeachingPayload(
            spoken_explanation="Gravity pulls objects together.",
            summary="Gravity is an attractive force.",
            whiteboard_blocks=[
                WhiteboardBlock(type="heading", content="Gravity"),
                WhiteboardBlock(type="equation", content="F = Gm1m2/r^2"),
            ],
            quiz=[
                QuizQuestion(
                    id="q1",
                    type="multiple_choice",
                    question="What does gravity do?",
                    options=["Attracts", "Repels"],
                    expected_answer="Attracts",
                    explanation="Masses attract.",
                ),
                QuizQuestion(
                    id="q2",
                    type="multiple_choice",
                    question="Which has gravity?",
                    options=["Mass", "Nothing"],
                    expected_answer="Mass",
                    explanation="All mass gravitates.",
                ),
                QuizQuestion(
                    id="q3",
                    type="short_answer",
                    question="Name the force.",
                    expected_answer="Gravity",
                    explanation="The force is gravity.",
                ),
            ],
            detected_misconceptions=[],
            learner_level_update="beginner",
            suggested_follow_up="Explore orbits.",
        )


class FakeTTS(TTSProvider):
    def __init__(self, audio_dir: Path):
        self.audio_dir = audio_dir

    async def synthesize(self, text: str, voice: str):
        audio_id = "11111111-1111-1111-1111-111111111111"
        output = self.audio_dir / f"{audio_id}.mp3"
        output.parent.mkdir(parents=True, exist_ok=True)
        output.write_bytes(b"fake-mp3")
        return audio_id, output


class FakeLiveSession:
    def __init__(self):
        self.received_audio = False
        self.delivered = False

    async def send_realtime_input(self, **kwargs):
        if kwargs.get("audio"):
            self.received_audio = True

    async def receive(self):
        while not self.received_audio or self.delivered:
            import asyncio

            await asyncio.sleep(0.01)
        self.delivered = True
        part = SimpleNamespace(
            inline_data=SimpleNamespace(data=b"fake-live-pcm")
        )
        content = SimpleNamespace(
            input_transcription=SimpleNamespace(text="Why does gravity work?"),
            output_transcription=SimpleNamespace(
                text="Gravity attracts objects with mass."
            ),
            model_turn=SimpleNamespace(parts=[part]),
            interrupted=False,
            turn_complete=True,
        )
        yield SimpleNamespace(server_content=content)


class FakeLive(LiveProvider):
    @asynccontextmanager
    async def connect(self, system_instruction: str):
        yield FakeLiveSession()


@pytest.fixture
def client():
    settings = get_settings()
    Base.metadata.drop_all(bind=engine)
    settings.audio_dir.mkdir(parents=True, exist_ok=True)
    with TestClient(app) as test_client:
        app.state.llm = FakeLLM()
        app.state.tts = FakeTTS(settings.audio_dir)
        app.state.live = FakeLive()
        yield test_client
    Base.metadata.drop_all(bind=engine)