"""Tests for portfolio optimization routes (TDD - RED phase first)."""

from unittest.mock import patch, AsyncMock

import pytest
from httpx import AsyncClient, ASGITransport

from main import app


@pytest.fixture
async def client():
    transport = ASGITransport(app=app)
    async with AsyncClient(transport=transport, base_url="http://test") as c:
        yield c


# --- POST /api/v1/portfolio/optimize ---


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.optimize_hrp", new_callable=AsyncMock)
async def test_portfolio_optimize_happy_path(mock_fn, client):
    mock_fn.return_value = {
        "weights": {"AAPL": 0.35, "MSFT": 0.32, "GOOGL": 0.33},
        "method": "hrp",
    }
    resp = await client.post(
        "/api/v1/portfolio/optimize",
        json={"symbols": ["AAPL", "MSFT", "GOOGL"], "days": 365},
    )
    assert resp.status_code == 200
    data = resp.json()
    assert data["success"] is True
    assert data["data"]["method"] == "hrp"
    assert "AAPL" in data["data"]["weights"]
    mock_fn.assert_called_once_with(["AAPL", "MSFT", "GOOGL"], days=365)


@pytest.mark.asyncio
async def test_portfolio_optimize_missing_symbols(client):
    resp = await client.post("/api/v1/portfolio/optimize", json={"days": 365})
    assert resp.status_code == 422


@pytest.mark.asyncio
async def test_portfolio_optimize_empty_symbols(client):
    resp = await client.post(
        "/api/v1/portfolio/optimize", json={"symbols": [], "days": 365}
    )
    assert resp.status_code == 422


@pytest.mark.asyncio
async def test_portfolio_optimize_too_many_symbols(client):
    symbols = [f"SYM{i}" for i in range(51)]
    resp = await client.post(
        "/api/v1/portfolio/optimize", json={"symbols": symbols, "days": 365}
    )
    assert resp.status_code == 422


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.optimize_hrp", new_callable=AsyncMock)
async def test_portfolio_optimize_service_error_returns_502(mock_fn, client):
    mock_fn.side_effect = RuntimeError("Computation failed")
    resp = await client.post(
        "/api/v1/portfolio/optimize",
        json={"symbols": ["AAPL", "MSFT"], "days": 365},
    )
    assert resp.status_code == 502


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.optimize_hrp", new_callable=AsyncMock)
async def test_portfolio_optimize_value_error_returns_400(mock_fn, client):
    mock_fn.side_effect = ValueError("No price data available")
    resp = await client.post(
        "/api/v1/portfolio/optimize",
        json={"symbols": ["AAPL", "MSFT"], "days": 365},
    )
    assert resp.status_code == 400


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.optimize_hrp", new_callable=AsyncMock)
async def test_portfolio_optimize_default_days(mock_fn, client):
    mock_fn.return_value = {"weights": {"AAPL": 1.0}, "method": "hrp"}
    resp = await client.post(
        "/api/v1/portfolio/optimize", json={"symbols": ["AAPL"]}
    )
    assert resp.status_code == 200
    mock_fn.assert_called_once_with(["AAPL"], days=365)


# --- POST /api/v1/portfolio/correlation ---


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.compute_correlation", new_callable=AsyncMock)
async def test_portfolio_correlation_happy_path(mock_fn, client):
    mock_fn.return_value = {
        "symbols": ["AAPL", "MSFT"],
        "matrix": [[1.0, 0.85], [0.85, 1.0]],
    }
    resp = await client.post(
        "/api/v1/portfolio/correlation",
        json={"symbols": ["AAPL", "MSFT"], "days": 365},
    )
    assert resp.status_code == 200
    data = resp.json()
    assert data["success"] is True
    assert data["data"]["symbols"] == ["AAPL", "MSFT"]
    assert data["data"]["matrix"][0][0] == pytest.approx(1.0)
    mock_fn.assert_called_once_with(["AAPL", "MSFT"], days=365)


@pytest.mark.asyncio
async def test_portfolio_correlation_missing_symbols(client):
    resp = await client.post("/api/v1/portfolio/correlation", json={"days": 365})
    assert resp.status_code == 422


@pytest.mark.asyncio
async def test_portfolio_correlation_empty_symbols(client):
    resp = await client.post(
        "/api/v1/portfolio/correlation", json={"symbols": [], "days": 365}
    )
    assert resp.status_code == 422


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.compute_correlation", new_callable=AsyncMock)
async def test_portfolio_correlation_service_error_returns_502(mock_fn, client):
    mock_fn.side_effect = RuntimeError("Failed")
    resp = await client.post(
        "/api/v1/portfolio/correlation",
        json={"symbols": ["AAPL", "MSFT"], "days": 365},
    )
    assert resp.status_code == 502


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.compute_correlation", new_callable=AsyncMock)
async def test_portfolio_correlation_value_error_returns_400(mock_fn, client):
    mock_fn.side_effect = ValueError("No price data available")
    resp = await client.post(
        "/api/v1/portfolio/correlation",
        json={"symbols": ["AAPL", "MSFT"], "days": 365},
    )
    assert resp.status_code == 400


# --- POST /api/v1/portfolio/risk-parity ---


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.compute_risk_parity", new_callable=AsyncMock)
async def test_portfolio_risk_parity_happy_path(mock_fn, client):
    mock_fn.return_value = {
        "weights": {"AAPL": 0.35, "MSFT": 0.33, "GOOGL": 0.32},
        "risk_contributions": {"AAPL": 0.34, "MSFT": 0.33, "GOOGL": 0.33},
        "method": "risk_parity",
    }
    resp = await client.post(
        "/api/v1/portfolio/risk-parity",
        json={"symbols": ["AAPL", "MSFT", "GOOGL"], "days": 365},
    )
    assert resp.status_code == 200
    data = resp.json()
    assert data["success"] is True
    assert data["data"]["method"] == "risk_parity"
    assert "risk_contributions" in data["data"]
    mock_fn.assert_called_once_with(["AAPL", "MSFT", "GOOGL"], days=365)


@pytest.mark.asyncio
async def test_portfolio_risk_parity_missing_symbols(client):
    resp = await client.post("/api/v1/portfolio/risk-parity", json={"days": 365})
    assert resp.status_code == 422


@pytest.mark.asyncio
async def test_portfolio_risk_parity_empty_symbols(client):
    resp = await client.post(
        "/api/v1/portfolio/risk-parity", json={"symbols": [], "days": 365}
    )
    assert resp.status_code == 422


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.compute_risk_parity", new_callable=AsyncMock)
async def test_portfolio_risk_parity_service_error_returns_502(mock_fn, client):
    mock_fn.side_effect = RuntimeError("Failed")
    resp = await client.post(
        "/api/v1/portfolio/risk-parity",
        json={"symbols": ["AAPL", "MSFT"], "days": 365},
    )
    assert resp.status_code == 502


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.compute_risk_parity", new_callable=AsyncMock)
async def test_portfolio_risk_parity_value_error_returns_400(mock_fn, client):
    mock_fn.side_effect = ValueError("No price data available")
    resp = await client.post(
        "/api/v1/portfolio/risk-parity",
        json={"symbols": ["AAPL", "MSFT"], "days": 365},
    )
    assert resp.status_code == 400


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.compute_risk_parity", new_callable=AsyncMock)
async def test_portfolio_risk_parity_default_days(mock_fn, client):
    mock_fn.return_value = {
        "weights": {"AAPL": 1.0},
        "risk_contributions": {"AAPL": 1.0},
        "method": "risk_parity",
    }
    resp = await client.post(
        "/api/v1/portfolio/risk-parity", json={"symbols": ["AAPL"]}
    )
    assert resp.status_code == 200
    mock_fn.assert_called_once_with(["AAPL"], days=365)


# ---------------------------------------------------------------------------
# POST /api/v1/portfolio/cluster
# ---------------------------------------------------------------------------

_CLUSTER_RESULT = {
    "symbols": ["AAPL", "MSFT", "GOOGL", "AMZN", "JPM", "BAC"],
    "coordinates": [
        {"symbol": "AAPL", "x": 12.5, "y": -3.2, "cluster": 0},
        {"symbol": "MSFT", "x": 11.8, "y": -2.9, "cluster": 0},
        {"symbol": "GOOGL", "x": 10.1, "y": -1.5, "cluster": 0},
        {"symbol": "AMZN", "x": 9.5, "y": -0.8, "cluster": 0},
        {"symbol": "JPM", "x": -5.1, "y": 8.3, "cluster": 1},
        {"symbol": "BAC", "x": -4.9, "y": 7.9, "cluster": 1},
    ],
    "clusters": {"0": ["AAPL", "MSFT", "GOOGL", "AMZN"], "1": ["JPM", "BAC"]},
    "method": "t-SNE + KMeans",
    "n_clusters": 2,
    "days": 180,
}


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.cluster_stocks", new_callable=AsyncMock)
async def test_portfolio_cluster_happy_path(mock_fn, client):
    """POST /cluster returns 200 with valid cluster result."""
    mock_fn.return_value = _CLUSTER_RESULT
    resp = await client.post(
        "/api/v1/portfolio/cluster",
        json={"symbols": ["AAPL", "MSFT", "GOOGL", "AMZN", "JPM", "BAC"], "days": 180},
    )
    assert resp.status_code == 200
    data = resp.json()
    assert data["success"] is True
    assert data["data"]["method"] == "t-SNE + KMeans"
    assert "coordinates" in data["data"]
    assert "clusters" in data["data"]
    mock_fn.assert_called_once_with(
        ["AAPL", "MSFT", "GOOGL", "AMZN", "JPM", "BAC"], days=180, n_clusters=None
    )


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.cluster_stocks", new_callable=AsyncMock)
async def test_portfolio_cluster_with_custom_n_clusters(mock_fn, client):
    """n_clusters is forwarded to service when provided."""
    mock_fn.return_value = _CLUSTER_RESULT
    resp = await client.post(
        "/api/v1/portfolio/cluster",
        json={
            "symbols": ["AAPL", "MSFT", "GOOGL", "AMZN", "JPM", "BAC"],
            "days": 180,
            "n_clusters": 3,
        },
    )
    assert resp.status_code == 200
    mock_fn.assert_called_once_with(
        ["AAPL", "MSFT", "GOOGL", "AMZN", "JPM", "BAC"], days=180, n_clusters=3
    )


@pytest.mark.asyncio
async def test_portfolio_cluster_too_few_symbols_returns_422(client):
    """Fewer than 3 symbols triggers Pydantic validation error (422)."""
    resp = await client.post(
        "/api/v1/portfolio/cluster",
        json={"symbols": ["AAPL", "MSFT"], "days": 180},
    )
    assert resp.status_code == 422


@pytest.mark.asyncio
async def test_portfolio_cluster_missing_symbols_returns_422(client):
    """Missing symbols field returns 422."""
    resp = await client.post("/api/v1/portfolio/cluster", json={"days": 180})
    assert resp.status_code == 422


@pytest.mark.asyncio
async def test_portfolio_cluster_too_many_symbols_returns_422(client):
    """More than 50 symbols returns 422."""
    symbols = [f"SYM{i}" for i in range(51)]
    resp = await client.post(
        "/api/v1/portfolio/cluster", json={"symbols": symbols, "days": 180}
    )
    assert resp.status_code == 422


@pytest.mark.asyncio
async def test_portfolio_cluster_days_below_minimum_returns_422(client):
    """days < 30 returns 422."""
    resp = await client.post(
        "/api/v1/portfolio/cluster",
        json={"symbols": ["AAPL", "MSFT", "GOOGL"], "days": 10},
    )
    assert resp.status_code == 422


@pytest.mark.asyncio
async def test_portfolio_cluster_n_clusters_below_minimum_returns_422(client):
    """n_clusters < 2 returns 422."""
    resp = await client.post(
        "/api/v1/portfolio/cluster",
        json={"symbols": ["AAPL", "MSFT", "GOOGL"], "days": 180, "n_clusters": 1},
    )
    assert resp.status_code == 422


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.cluster_stocks", new_callable=AsyncMock)
async def test_portfolio_cluster_value_error_returns_400(mock_fn, client):
    """ValueError from service returns 400."""
    mock_fn.side_effect = ValueError("at least 3 symbols required")
    resp = await client.post(
        "/api/v1/portfolio/cluster",
        json={"symbols": ["AAPL", "MSFT", "GOOGL"], "days": 180},
    )
    assert resp.status_code == 400


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.cluster_stocks", new_callable=AsyncMock)
async def test_portfolio_cluster_upstream_error_returns_502(mock_fn, client):
    """Unexpected exception from service returns 502."""
    mock_fn.side_effect = RuntimeError("upstream failure")
    resp = await client.post(
        "/api/v1/portfolio/cluster",
        json={"symbols": ["AAPL", "MSFT", "GOOGL"], "days": 180},
    )
    assert resp.status_code == 502


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.cluster_stocks", new_callable=AsyncMock)
async def test_portfolio_cluster_default_days(mock_fn, client):
    """Default days=180 is used when not provided."""
    mock_fn.return_value = _CLUSTER_RESULT
    resp = await client.post(
        "/api/v1/portfolio/cluster",
        json={"symbols": ["AAPL", "MSFT", "GOOGL"]},
    )
    assert resp.status_code == 200
    mock_fn.assert_called_once_with(
        ["AAPL", "MSFT", "GOOGL"], days=180, n_clusters=None
    )


# ---------------------------------------------------------------------------
# POST /api/v1/portfolio/similar
# ---------------------------------------------------------------------------

_SIMILAR_RESULT = {
    "symbol": "AAPL",
    "most_similar": [
        {"symbol": "MSFT", "correlation": 0.85},
        {"symbol": "GOOGL", "correlation": 0.78},
    ],
    "least_similar": [
        {"symbol": "JPM", "correlation": 0.32},
        {"symbol": "BAC", "correlation": 0.28},
    ],
}


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.find_similar_stocks", new_callable=AsyncMock)
async def test_portfolio_similar_happy_path(mock_fn, client):
    """POST /similar returns 200 with most_similar and least_similar."""
    mock_fn.return_value = _SIMILAR_RESULT
    resp = await client.post(
        "/api/v1/portfolio/similar",
        json={
            "symbol": "AAPL",
            "universe": ["MSFT", "GOOGL", "AMZN", "JPM", "BAC"],
            "days": 180,
            "top_n": 2,
        },
    )
    assert resp.status_code == 200
    data = resp.json()
    assert data["success"] is True
    assert data["data"]["symbol"] == "AAPL"
    assert "most_similar" in data["data"]
    assert "least_similar" in data["data"]
    mock_fn.assert_called_once_with(
        "AAPL",
        ["MSFT", "GOOGL", "AMZN", "JPM", "BAC"],
        days=180,
        top_n=2,
    )


@pytest.mark.asyncio
async def test_portfolio_similar_missing_symbol_returns_422(client):
    """Missing symbol field returns 422."""
    resp = await client.post(
        "/api/v1/portfolio/similar",
        json={"universe": ["MSFT", "GOOGL"], "days": 180},
    )
    assert resp.status_code == 422


@pytest.mark.asyncio
async def test_portfolio_similar_missing_universe_returns_422(client):
    """Missing universe field returns 422."""
    resp = await client.post(
        "/api/v1/portfolio/similar",
        json={"symbol": "AAPL", "days": 180},
    )
    assert resp.status_code == 422


@pytest.mark.asyncio
async def test_portfolio_similar_universe_too_small_returns_422(client):
    """universe with fewer than 2 entries returns 422."""
    resp = await client.post(
        "/api/v1/portfolio/similar",
        json={"symbol": "AAPL", "universe": ["MSFT"], "days": 180},
    )
    assert resp.status_code == 422


@pytest.mark.asyncio
async def test_portfolio_similar_top_n_below_minimum_returns_422(client):
    """top_n < 1 returns 422."""
    resp = await client.post(
        "/api/v1/portfolio/similar",
        json={"symbol": "AAPL", "universe": ["MSFT", "GOOGL"], "days": 180, "top_n": 0},
    )
    assert resp.status_code == 422


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.find_similar_stocks", new_callable=AsyncMock)
async def test_portfolio_similar_value_error_returns_400(mock_fn, client):
    """ValueError from service returns 400."""
    mock_fn.side_effect = ValueError("AAPL not found in price data")
    resp = await client.post(
        "/api/v1/portfolio/similar",
        json={"symbol": "AAPL", "universe": ["MSFT", "GOOGL"], "days": 180},
    )
    assert resp.status_code == 400


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.find_similar_stocks", new_callable=AsyncMock)
async def test_portfolio_similar_upstream_error_returns_502(mock_fn, client):
    """Unexpected exception from service returns 502."""
    mock_fn.side_effect = RuntimeError("upstream failure")
    resp = await client.post(
        "/api/v1/portfolio/similar",
        json={"symbol": "AAPL", "universe": ["MSFT", "GOOGL"], "days": 180},
    )
    assert resp.status_code == 502


@pytest.mark.asyncio
@patch("routes_portfolio.portfolio_service.find_similar_stocks", new_callable=AsyncMock)
async def test_portfolio_similar_default_top_n(mock_fn, client):
    """Default top_n=5 is passed to service when not specified."""
    mock_fn.return_value = _SIMILAR_RESULT
    resp = await client.post(
        "/api/v1/portfolio/similar",
        json={"symbol": "AAPL", "universe": ["MSFT", "GOOGL", "AMZN"]},
    )
    assert resp.status_code == 200
    mock_fn.assert_called_once_with("AAPL", ["MSFT", "GOOGL", "AMZN"], days=180, top_n=5)