"""Tests for binance_rest module."""

import pytest
from decimal import Decimal
from unittest.mock import AsyncMock, MagicMock
from datetime import datetime, timezone

from data_collector.binance_rest import fetch_historical_candles


@pytest.mark.asyncio
async def test_fetch_historical_candles_parses_response():
    """Verify that OHLCV rows are correctly parsed into Candle models."""
    ts = 1700000000000  # milliseconds
    mock_exchange = MagicMock()
    mock_exchange.fetch_ohlcv = AsyncMock(
        return_value=[
            [ts, 30000.0, 30100.0, 29900.0, 30050.0, 1.5],
            [ts + 60000, 30050.0, 30200.0, 30000.0, 30150.0, 2.0],
        ]
    )

    candles = await fetch_historical_candles(mock_exchange, "BTC/USDT", "1m", since=ts, limit=500)

    assert len(candles) == 2

    c = candles[0]
    assert c.symbol == "BTCUSDT"
    assert c.timeframe == "1m"
    assert c.open_time == datetime.fromtimestamp(ts / 1000, tz=timezone.utc)
    assert c.open == Decimal("30000.0")
    assert c.high == Decimal("30100.0")
    assert c.low == Decimal("29900.0")
    assert c.close == Decimal("30050.0")
    assert c.volume == Decimal("1.5")

    mock_exchange.fetch_ohlcv.assert_called_once_with("BTC/USDT", "1m", since=ts, limit=500)


@pytest.mark.asyncio
async def test_fetch_historical_candles_empty_response():
    """Verify that an empty exchange response returns an empty list."""
    mock_exchange = MagicMock()
    mock_exchange.fetch_ohlcv = AsyncMock(return_value=[])

    candles = await fetch_historical_candles(mock_exchange, "BTC/USDT", "1m", since=1700000000000)

    assert candles == []