const React = require("react");
const { render } = require("ink-testing-library");
const {
	PerformanceBenchmark,
	PerformanceProfiler,
	MemoryMonitor,
} = require("../../../src/tui/utils/performanceUtils.js");

// Import optimized components
const OptimizedMenuList = require("../../../src/tui/components/common/OptimizedMenuList.jsx");
const VirtualScrollableContainer = require("../../../src/tui/components/common/VirtualScrollableContainer.jsx");
const OptimizedProgressBar = require("../../../src/tui/components/common/OptimizedProgressBar.jsx");

// Import original components for comparison
const MenuList = require("../../../src/tui/components/common/MenuList.jsx");
const ScrollableContainer = require("../../../src/tui/components/common/ScrollableContainer.jsx");
const ProgressBar = require("../../../src/tui/components/common/ProgressBar.jsx");

/**
 * Performance tests for TUI component rendering
 * Requirements: 4.1, 4.3, 4.4
 */

describe("TUI Component Rendering Performance", () => {
	let profiler;
	let memoryMonitor;

	beforeEach(() => {
		profiler = new PerformanceProfiler();
		memoryMonitor = new MemoryMonitor();
	});

	afterEach(() => {
		profiler.clear();
		memoryMonitor.stopMonitoring();
	});

	describe("MenuList Performance", () => {
		const generateMenuItems = (count) => {
			return Array.from({ length: count }, (_, i) => ({
				label: `Menu Item ${i + 1}`,
				shortcut: String.fromCharCode(97 + (i % 26)), // a-z
				description: `Description for menu item ${i + 1}`,
			}));
		};

		test("should render small menu lists efficiently", async () => {
			const items = generateMenuItems(10);
			const benchmark = new PerformanceBenchmark("Small MenuList Rendering");

			const testFunction = () => {
				const { unmount } = render(
					React.createElement(OptimizedMenuList, {
						items,
						selectedIndex: 0,
						onSelect: () => {},
						showShortcuts: true,
					})
				);
				unmount();
			};

			const results = await benchmark.run(testFunction, 100);

			expect(results.average).toBeLessThan(10); // Should render in less than 10ms on average
			expect(results.p95).toBeLessThan(20); // 95% of renders should be under 20ms

			benchmark.logResults();
		});

		test("should handle large menu lists with virtual scrolling", async () => {
			const items = generateMenuItems(1000);
			const benchmark = new PerformanceBenchmark("Large MenuList Rendering");

			const testFunction = () => {
				const { unmount } = render(
					React.createElement(OptimizedMenuList, {
						items,
						selectedIndex: 0,
						onSelect: () => {},
						showShortcuts: true,
					})
				);
				unmount();
			};

			const results = await benchmark.run(testFunction, 50);

			expect(results.average).toBeLessThan(50); // Should render in less than 50ms on average
			expect(results.p95).toBeLessThan(100); // 95% of renders should be under 100ms

			benchmark.logResults();
		});

		test("should show performance improvement over original MenuList", async () => {
			const items = generateMenuItems(500);

			// Benchmark original MenuList
			const originalBenchmark = new PerformanceBenchmark("Original MenuList");
			const originalTestFunction = () => {
				const { unmount } = render(
					React.createElement(MenuList, {
						items,
						selectedIndex: 0,
						onSelect: () => {},
						showShortcuts: true,
					})
				);
				unmount();
			};
			const originalResults = await originalBenchmark.run(
				originalTestFunction,
				30
			);

			// Benchmark optimized MenuList
			const optimizedBenchmark = new PerformanceBenchmark("Optimized MenuList");
			const optimizedTestFunction = () => {
				const { unmount } = render(
					React.createElement(OptimizedMenuList, {
						items,
						selectedIndex: 0,
						onSelect: () => {},
						showShortcuts: true,
					})
				);
				unmount();
			};
			const optimizedResults = await optimizedBenchmark.run(
				optimizedTestFunction,
				30
			);

			// Optimized version should be at least 20% faster
			const improvement =
				(originalResults.average - optimizedResults.average) /
				originalResults.average;
			expect(improvement).toBeGreaterThan(0.2);

			console.log(
				`Performance improvement: ${(improvement * 100).toFixed(1)}%`
			);
			originalBenchmark.logResults();
			optimizedBenchmark.logResults();
		});
	});

	describe("VirtualScrollableContainer Performance", () => {
		const generateScrollItems = (count) => {
			return Array.from({ length: count }, (_, i) => ({
				id: i,
				content: `Item ${
					i + 1
				} - Lorem ipsum dolor sit amet, consectetur adipiscing elit.`,
			}));
		};

		const renderItem = (item, index) => {
			return React.createElement("div", { key: index }, item.content);
		};

		test("should handle large datasets efficiently with virtual scrolling", async () => {
			const items = generateScrollItems(10000);
			const benchmark = new PerformanceBenchmark(
				"Virtual Scrolling Large Dataset"
			);

			memoryMonitor.startMonitoring(1000);

			const testFunction = () => {
				const { unmount } = render(
					React.createElement(VirtualScrollableContainer, {
						items,
						renderItem,
						itemHeight: 1,
						showScrollIndicators: true,
					})
				);
				unmount();
			};

			const results = await benchmark.run(testFunction, 20);

			// Should handle large datasets efficiently
			expect(results.average).toBeLessThan(100); // Should render in less than 100ms
			expect(results.p95).toBeLessThan(200); // 95% of renders should be under 200ms

			// Check memory usage
			const memoryStats = memoryMonitor.getStatistics();
			const memoryLeak = memoryMonitor.checkForLeaks();

			expect(memoryLeak.isLikely).toBe(false); // Should not have memory leaks

			benchmark.logResults();
			memoryMonitor.logSummary();
		});

		test("should maintain consistent performance with different scroll positions", async () => {
			const items = generateScrollItems(5000);
			const scrollPositions = [0, 100, 500, 1000, 2500, 4999];
			const results = [];

			for (const scrollPosition of scrollPositions) {
				const benchmark = new PerformanceBenchmark(
					`Virtual Scroll Position ${scrollPosition}`
				);

				const testFunction = () => {
					const { unmount } = render(
						React.createElement(VirtualScrollableContainer, {
							items,
							renderItem,
							itemHeight: 1,
							initialScrollPosition: scrollPosition,
						})
					);
					unmount();
				};

				const result = await benchmark.run(testFunction, 20);
				results.push(result.average);
			}

			// Performance should be consistent across different scroll positions
			const maxVariation = Math.max(...results) - Math.min(...results);
			const averageTime =
				results.reduce((sum, time) => sum + time, 0) / results.length;
			const variationPercentage = (maxVariation / averageTime) * 100;

			expect(variationPercentage).toBeLessThan(50); // Variation should be less than 50%

			console.log(
				`Scroll position performance variation: ${variationPercentage.toFixed(
					1
				)}%`
			);
		});
	});

	describe("ProgressBar Performance", () => {
		test("should handle rapid progress updates efficiently", async () => {
			const benchmark = new PerformanceBenchmark("Rapid Progress Updates");

			memoryMonitor.startMonitoring(500);

			const testFunction = () => {
				let progress = 0;
				const { rerender, unmount } = render(
					React.createElement(OptimizedProgressBar, {
						progress,
						label: "Test Progress",
						animate: true,
						debounceDelay: 50,
					})
				);

				// Simulate rapid updates
				for (let i = 0; i < 100; i++) {
					progress = i;
					rerender(
						React.createElement(OptimizedProgressBar, {
							progress,
							label: "Test Progress",
							animate: true,
							debounceDelay: 50,
						})
					);
				}

				unmount();
			};

			const results = await benchmark.run(testFunction, 10);

			expect(results.average).toBeLessThan(200); // Should handle rapid updates efficiently

			// Check for memory leaks during rapid updates
			const memoryLeak = memoryMonitor.checkForLeaks();
			expect(memoryLeak.isLikely).toBe(false);

			benchmark.logResults();
			memoryMonitor.logSummary();
		});

		test("should optimize multi-progress bar rendering", async () => {
			const progressItems = Array.from({ length: 20 }, (_, i) => ({
				key: `progress-${i}`,
				label: `Operation ${i + 1}`,
				progress: Math.random() * 100,
				color: ["blue", "green", "yellow", "cyan", "magenta"][i % 5],
			}));

			const benchmark = new PerformanceBenchmark(
				"Multi-Progress Bar Rendering"
			);

			const testFunction = () => {
				const { unmount } = render(
					React.createElement(OptimizedProgressBar.Multi, {
						progressItems,
						width: 40,
						showLabels: true,
						showPercentages: true,
						animate: false,
					})
				);
				unmount();
			};

			const results = await benchmark.run(testFunction, 50);

			expect(results.average).toBeLessThan(30); // Should render multiple progress bars efficiently
			expect(results.p95).toBeLessThan(60);

			benchmark.logResults();
		});
	});

	describe("Memory Management", () => {
		test("should not leak memory during component lifecycle", async () => {
			const items = Array.from({ length: 1000 }, (_, i) => `Item ${i + 1}`);

			memoryMonitor.startMonitoring(500);

			// Create and destroy components multiple times
			for (let i = 0; i < 50; i++) {
				const { unmount } = render(
					React.createElement(OptimizedMenuList, {
						items,
						selectedIndex: i % items.length,
						onSelect: () => {},
						showShortcuts: true,
					})
				);

				// Simulate some async operations
				await new Promise((resolve) => setTimeout(resolve, 10));

				unmount();
			}

			// Wait for garbage collection
			await new Promise((resolve) => setTimeout(resolve, 1000));

			const memoryLeak = memoryMonitor.checkForLeaks();
			const memoryStats = memoryMonitor.getStatistics();

			expect(memoryLeak.isLikely).toBe(false);
			expect(memoryStats.growth.heapUsed).toBeLessThan(50 * 1024 * 1024); // Less than 50MB growth

			memoryMonitor.logSummary();
		});

		test("should clean up event listeners and timers", async () => {
			const initialHandlers = process.listenerCount("uncaughtException");

			// Create components with timers and event listeners
			const components = [];
			for (let i = 0; i < 10; i++) {
				const { unmount } = render(
					React.createElement(OptimizedProgressBar, {
						progress: 50,
						animate: true,
						animationSpeed: 100,
					})
				);
				components.push(unmount);
			}

			// Unmount all components
			components.forEach((unmount) => unmount());

			// Wait for cleanup
			await new Promise((resolve) => setTimeout(resolve, 500));

			const finalHandlers = process.listenerCount("uncaughtException");

			// Should not have increased the number of event listeners
			expect(finalHandlers).toBeLessThanOrEqual(initialHandlers + 1);
		});
	});

	describe("Debouncing and Throttling", () => {
		test("should reduce render frequency with debouncing", async () => {
			let renderCount = 0;
			const TestComponent = () => {
				renderCount++;
				return React.createElement("div", null, "Test");
			};

			const { rerender } = render(React.createElement(TestComponent));

			// Trigger multiple rapid re-renders
			for (let i = 0; i < 100; i++) {
				rerender(React.createElement(TestComponent));
			}

			// With proper debouncing, render count should be significantly less than 100
			expect(renderCount).toBeLessThan(50);
		});

		test("should maintain responsiveness with throttling", async () => {
			const updates = [];
			let lastUpdate = Date.now();

			const TestComponent = ({ value }) => {
				const currentTime = Date.now();
				updates.push(currentTime - lastUpdate);
				lastUpdate = currentTime;
				return React.createElement("div", null, value);
			};

			const { rerender } = render(
				React.createElement(TestComponent, { value: 0 })
			);

			// Simulate rapid updates with throttling
			for (let i = 1; i <= 50; i++) {
				await new Promise((resolve) => setTimeout(resolve, 10));
				rerender(React.createElement(TestComponent, { value: i }));
			}

			// Updates should be throttled but still responsive
			const averageInterval =
				updates.reduce((sum, interval) => sum + interval, 0) / updates.length;
			expect(averageInterval).toBeGreaterThan(5); // Should be throttled
			expect(averageInterval).toBeLessThan(100); // But still responsive
		});
	});
});

describe("Performance Regression Tests", () => {
	test("should maintain performance benchmarks", async () => {
		const benchmarks = {
			smallMenuList: { maxAverage: 10, maxP95: 20 },
			largeMenuList: { maxAverage: 50, maxP95: 100 },
			virtualScrolling: { maxAverage: 100, maxP95: 200 },
			progressBar: { maxAverage: 30, maxP95: 60 },
		};

		// This test would be run in CI to ensure performance doesn't regress
		// For now, we'll just verify the benchmarks structure
		expect(benchmarks).toBeDefined();
		expect(Object.keys(benchmarks)).toHaveLength(4);
	});
});