"""
Tests for engine.benchmark module - performance regression tests.
"""

from unittest.mock import patch

import pytest

from engine.display import NullDisplay


class TestBenchmarkNullDisplay:
    """Performance tests for NullDisplay - regression tests."""

    @pytest.mark.benchmark
    def test_null_display_minimum_fps(self):
        """NullDisplay should meet minimum performance threshold."""
        import time

        display = NullDisplay()
        display.init(80, 24)
        buffer = ["x" * 80 for _ in range(24)]

        iterations = 1000
        start = time.perf_counter()
        for _ in range(iterations):
            display.show(buffer)
        elapsed = time.perf_counter() - start

        fps = iterations / elapsed
        min_fps = 20000

        assert fps >= min_fps, f"NullDisplay FPS {fps:.0f} below minimum {min_fps}"

    @pytest.mark.benchmark
    def test_effects_minimum_throughput(self):
        """Effects should meet minimum processing throughput."""
        import time

        from effects_plugins import discover_plugins
        from engine.effects import EffectContext, get_registry

        discover_plugins()
        registry = get_registry()
        effect = registry.get("noise")
        assert effect is not None, "Noise effect should be registered"

        buffer = ["x" * 80 for _ in range(24)]
        ctx = EffectContext(
            terminal_width=80,
            terminal_height=24,
            scroll_cam=0,
            ticker_height=20,
            mic_excess=0.0,
            grad_offset=0.0,
            frame_number=0,
            has_message=False,
        )

        iterations = 500
        start = time.perf_counter()
        for _ in range(iterations):
            effect.process(buffer, ctx)
        elapsed = time.perf_counter() - start

        fps = iterations / elapsed
        min_fps = 10000

        assert fps >= min_fps, (
            f"Effect processing FPS {fps:.0f} below minimum {min_fps}"
        )


class TestBenchmarkWebSocketDisplay:
    """Performance tests for WebSocketDisplay."""

    @pytest.mark.benchmark
    def test_websocket_display_minimum_fps(self):
        """WebSocketDisplay should meet minimum performance threshold."""
        import time

        with patch("engine.display.backends.websocket.websockets", None):
            from engine.display import WebSocketDisplay

            display = WebSocketDisplay()
            display.init(80, 24)
            buffer = ["x" * 80 for _ in range(24)]

            iterations = 500
            start = time.perf_counter()
            for _ in range(iterations):
                display.show(buffer)
            elapsed = time.perf_counter() - start

            fps = iterations / elapsed
            min_fps = 10000

            assert fps >= min_fps, (
                f"WebSocketDisplay FPS {fps:.0f} below minimum {min_fps}"
            )