const LogReaderService = require("../../../../src/services/logReader");

// Mock the LogReaderService
jest.mock("../../../../src/services/logReader");

describe("LogViewerScreen - Auto Refresh", () => {
	let mockLogReader;
	let mockPaginatedData;

	beforeEach(() => {
		jest.clearAllMocks();
		jest.useFakeTimers();

		// Setup mock data
		mockPaginatedData = {
			entries: [
				{
					id: "entry_1",
					type: "operation_start",
					timestamp: new Date("2025-08-06T20:30:00Z"),
					level: "INFO",
					message: "Price Update Operation Started",
					title: "Price Update Operation",
					details: "Target Tag: summer-sale\nPrice Adjustment: -10%",
				},
			],
			pagination: {
				currentPage: 0,
				pageSize: 10,
				totalEntries: 1,
				totalPages: 1,
				hasNextPage: false,
				hasPreviousPage: false,
				startIndex: 1,
				endIndex: 1,
			},
			filters: {
				levelFilter: "ALL",
				searchTerm: "",
			},
		};

		// Setup LogReaderService mock
		mockLogReader = {
			getPaginatedEntries: jest.fn().mockResolvedValue(mockPaginatedData),
			getLogStatistics: jest.fn().mockResolvedValue({}),
			clearCache: jest.fn(),
			watchFile: jest.fn().mockReturnValue(() => {}),
		};

		LogReaderService.mockImplementation(() => mockLogReader);
	});

	afterEach(() => {
		jest.useRealTimers();
	});

	describe("File Watching", () => {
		test("sets up file watching on mount", () => {
			const logReader = new LogReaderService();

			// Simulate component mount
			const cleanup = logReader.watchFile(() => {});

			expect(mockLogReader.watchFile).toHaveBeenCalled();
			expect(typeof cleanup).toBe("function");
		});

		test("calls refresh callback when file changes", () => {
			const logReader = new LogReaderService();
			const mockCallback = jest.fn();

			// Set up file watching
			logReader.watchFile(mockCallback);

			// Get the callback that was passed to watchFile
			const watchCallback = mockLogReader.watchFile.mock.calls[0][0];

			// Simulate file change
			watchCallback();

			expect(mockCallback).toHaveBeenCalled();
		});

		test("cleans up file watching on unmount", () => {
			const logReader = new LogReaderService();
			const mockCleanup = jest.fn();

			mockLogReader.watchFile.mockReturnValue(mockCleanup);

			const cleanup = logReader.watchFile(() => {});
			cleanup();

			expect(mockCleanup).toHaveBeenCalled();
		});
	});

	describe("Periodic Refresh", () => {
		test("sets up periodic refresh timer", async () => {
			const logReader = new LogReaderService();

			// Simulate component with auto-refresh enabled
			const refreshEnabled = true;

			if (refreshEnabled) {
				// Set up a timer (simulating the component's useEffect)
				const timer = setInterval(() => {
					logReader.clearCache();
				}, 30000);

				// Verify that timer was created
				expect(jest.getTimerCount()).toBeGreaterThan(0);

				// Clean up
				clearInterval(timer);
			}
		});

		test("respects auto-refresh toggle", () => {
			const logReader = new LogReaderService();

			// When auto-refresh is disabled, no timers should be set
			const refreshEnabled = false;

			if (!refreshEnabled) {
				expect(jest.getTimerCount()).toBe(0);
			}
		});

		test("prevents refresh when already loading", async () => {
			const logReader = new LogReaderService();

			// Simulate loading state
			const isLoading = true;
			const isRefreshing = false;

			// Periodic refresh should not trigger when loading
			if (!isLoading && !isRefreshing) {
				logReader.clearCache();
				await logReader.getPaginatedEntries({});
			}

			// If loading, clearCache should not be called
			if (isLoading) {
				expect(mockLogReader.clearCache).not.toHaveBeenCalled();
			}
		});

		test("prevents refresh when already refreshing", async () => {
			const logReader = new LogReaderService();

			// Simulate refreshing state
			const isLoading = false;
			const isRefreshing = true;

			// Periodic refresh should not trigger when already refreshing
			if (!isLoading && !isRefreshing) {
				logReader.clearCache();
				await logReader.getPaginatedEntries({});
			}

			// If refreshing, clearCache should not be called
			if (isRefreshing) {
				expect(mockLogReader.clearCache).not.toHaveBeenCalled();
			}
		});
	});

	describe("Cache Management", () => {
		test("clears cache before refresh", async () => {
			const logReader = new LogReaderService();

			// Simulate manual refresh
			logReader.clearCache();
			await logReader.getPaginatedEntries({});

			expect(mockLogReader.clearCache).toHaveBeenCalled();
			expect(mockLogReader.getPaginatedEntries).toHaveBeenCalled();
		});

		test("maintains cache for regular navigation", async () => {
			const logReader = new LogReaderService();

			// Simulate regular pagination (no cache clear)
			await logReader.getPaginatedEntries({ page: 1 });

			expect(mockLogReader.clearCache).not.toHaveBeenCalled();
			expect(mockLogReader.getPaginatedEntries).toHaveBeenCalledWith(
				expect.objectContaining({ page: 1 })
			);
		});
	});

	describe("Refresh State Management", () => {
		test("distinguishes between loading and refreshing states", async () => {
			const logReader = new LogReaderService();

			// Initial load should be "loading"
			const isInitialLoad = true;
			const isAutoRefresh = false;

			if (isInitialLoad && !isAutoRefresh) {
				// This would set loading state
				expect(true).toBe(true); // Placeholder for state check
			}

			// Auto refresh should be "refreshing"
			if (!isInitialLoad && isAutoRefresh) {
				// This would set refreshing state
				expect(true).toBe(true); // Placeholder for state check
			}
		});

		test("updates last refresh timestamp", async () => {
			const logReader = new LogReaderService();
			const beforeRefresh = new Date();

			// Simulate refresh
			await logReader.getPaginatedEntries({});

			const afterRefresh = new Date();

			// Last refresh should be between before and after
			expect(afterRefresh.getTime()).toBeGreaterThanOrEqual(
				beforeRefresh.getTime()
			);
		});
	});

	describe("Performance Optimization", () => {
		test("avoids unnecessary refreshes", () => {
			const logReader = new LogReaderService();

			// Multiple rapid file change events should be handled efficiently
			const watchCallback = mockLogReader.watchFile.mock.calls[0]?.[0];

			if (watchCallback) {
				// Simulate rapid file changes
				watchCallback();
				watchCallback();
				watchCallback();

				// Should handle gracefully without excessive API calls
				expect(mockLogReader.watchFile).toHaveBeenCalledTimes(1);
			}
		});

		test("handles refresh errors gracefully", async () => {
			const logReader = new LogReaderService();

			// Mock refresh failure
			mockLogReader.getPaginatedEntries.mockRejectedValueOnce(
				new Error("Refresh failed")
			);

			try {
				await logReader.getPaginatedEntries({});
			} catch (error) {
				expect(error.message).toBe("Refresh failed");
			}

			// Should still be able to retry
			mockLogReader.getPaginatedEntries.mockResolvedValueOnce(
				mockPaginatedData
			);
			const result = await logReader.getPaginatedEntries({});
			expect(result).toEqual(mockPaginatedData);
		});

		test("maintains selection during refresh", async () => {
			const logReader = new LogReaderService();

			// Simulate refresh with current selection
			const currentSelection = 0;
			const result = await logReader.getPaginatedEntries({});

			// Selection should be maintained if still valid
			if (currentSelection < result.entries.length) {
				expect(currentSelection).toBeLessThan(result.entries.length);
			}
		});
	});

	describe("Auto-refresh Toggle", () => {
		test("enables auto-refresh by default", () => {
			// Auto-refresh should be enabled by default
			const defaultAutoRefresh = true;
			expect(defaultAutoRefresh).toBe(true);
		});

		test("allows toggling auto-refresh", () => {
			let autoRefresh = true;

			// Toggle off
			autoRefresh = !autoRefresh;
			expect(autoRefresh).toBe(false);

			// Toggle on
			autoRefresh = !autoRefresh;
			expect(autoRefresh).toBe(true);
		});

		test("stops file watching when auto-refresh is disabled", () => {
			const logReader = new LogReaderService();
			const autoRefresh = false;

			// When auto-refresh is disabled, file watching should not be set up
			if (autoRefresh) {
				logReader.watchFile(() => {});
				expect(mockLogReader.watchFile).toHaveBeenCalled();
			} else {
				expect(mockLogReader.watchFile).not.toHaveBeenCalled();
			}
		});

		test("stops periodic refresh when auto-refresh is disabled", () => {
			const autoRefresh = false;

			// When auto-refresh is disabled, no periodic timers should be active
			if (!autoRefresh) {
				expect(jest.getTimerCount()).toBe(0);
			}
		});
	});

	describe("Visual Indicators", () => {
		test("shows different states in status bar", () => {
			// Test different status messages
			const states = [
				{ loading: true, refreshing: false, expected: "Loading..." },
				{ loading: false, refreshing: true, expected: "Refreshing..." },
				{ loading: false, refreshing: false, expected: "Filter status" },
			];

			states.forEach(({ loading, refreshing, expected }) => {
				let statusMessage;
				if (loading) {
					statusMessage = "Loading...";
				} else if (refreshing) {
					statusMessage = "Refreshing...";
				} else {
					statusMessage = "Filter status";
				}

				expect(statusMessage).toContain(expected.split(" ")[0]);
			});
		});

		test("displays auto-refresh status", () => {
			const autoRefresh = true;
			const statusText = `Auto: ${autoRefresh ? "ON" : "OFF"}`;

			expect(statusText).toBe("Auto: ON");
		});

		test("displays last refresh time", () => {
			const lastRefresh = new Date();
			const timeString = lastRefresh.toLocaleTimeString();

			expect(timeString).toMatch(/\d{1,2}:\d{2}:\d{2}/);
		});
	});

	describe("Error Handling", () => {
		test("handles file watching errors gracefully", () => {
			const logReader = new LogReaderService();

			// Mock file watching error
			mockLogReader.watchFile.mockImplementation(() => {
				throw new Error("File watching failed");
			});

			// Should not crash the application
			expect(() => {
				try {
					logReader.watchFile(() => {});
				} catch (error) {
					// Error should be handled gracefully
					expect(error.message).toBe("File watching failed");
				}
			}).not.toThrow();
		});

		test("continues working after refresh errors", async () => {
			const logReader = new LogReaderService();

			// Mock temporary error
			mockLogReader.getPaginatedEntries
				.mockRejectedValueOnce(new Error("Temporary error"))
				.mockResolvedValueOnce(mockPaginatedData);

			// First call fails
			try {
				await logReader.getPaginatedEntries({});
			} catch (error) {
				expect(error.message).toBe("Temporary error");
			}

			// Second call succeeds
			const result = await logReader.getPaginatedEntries({});
			expect(result).toEqual(mockPaginatedData);
		});
	});
});