// __tests__/unit/services/emailService.test.js
const emailServiceModule = require("../../../src/services/emailService"); // Adjust path
const { Resend } = require("resend");
const logger = require("../../../config/logger"); // Adjust path

jest.mock("resend"); // Mock the Resend constructor and its methods
jest.mock("../../../config/logger"); // Mock logger to spy on it

describe("Email Service (Resend)", () => {
	const mockSend = jest.fn();
	const originalResendApiKey = process.env.RESEND_API_KEY;
	const originalEmailFrom = process.env.EMAIL_FROM_ADDRESS;

	beforeEach(() => {
		mockSend.mockClear();
		Resend.mockClear();
		Resend.mockImplementation(() => ({
			emails: { send: mockSend },
		}));
		// Ensure env vars are set for these tests
		process.env.RESEND_API_KEY = "test-resend-api-key";
		process.env.EMAIL_FROM_ADDRESS = "sender@example.com";
	});

	afterAll(() => {
		process.env.RESEND_API_KEY = originalResendApiKey;
		process.env.EMAIL_FROM_ADDRESS = originalEmailFrom;
	});

	describe("sendSubmissionNotification", () => {
		const form = {
			name: "Test Form",
			email_notifications_enabled: true,
			notification_email_address: "custom@example.com",
		};
		const submissionData = { name: "John Doe", message: "Hello" };
		const userOwnerEmail = "owner@example.com";

		it("should send email if notifications enabled and custom address provided", async () => {
			mockSend.mockResolvedValue({ data: { id: "email_id_123" }, error: null });
			await emailServiceModule.sendSubmissionNotification(
				form,
				submissionData,
				userOwnerEmail
			);

			expect(Resend).toHaveBeenCalledWith("test-resend-api-key");
			expect(mockSend).toHaveBeenCalledWith({
				from: "sender@example.com",
				to: "custom@example.com",
				subject: "New Submission for Form: Test Form",
				html: expect.stringContaining("<strong>Test Form</strong>"),
			});
			expect(logger.info).toHaveBeenCalledWith(
				expect.stringContaining("Submission email sent successfully")
			);
		});

		it("should use owner email if custom address not provided", async () => {
			const formNoCustomEmail = { ...form, notification_email_address: null };
			mockSend.mockResolvedValue({ data: { id: "email_id_123" }, error: null });
			await emailServiceModule.sendSubmissionNotification(
				formNoCustomEmail,
				submissionData,
				userOwnerEmail
			);

			expect(mockSend).toHaveBeenCalledWith(
				expect.objectContaining({
					to: "owner@example.com",
				})
			);
		});

		it("should not send email if notifications are disabled", async () => {
			const disabledForm = { ...form, email_notifications_enabled: false };
			await emailServiceModule.sendSubmissionNotification(
				disabledForm,
				submissionData,
				userOwnerEmail
			);
			expect(mockSend).not.toHaveBeenCalled();
			expect(logger.info).toHaveBeenCalledWith(
				expect.stringContaining("Email notifications are disabled")
			);
		});

		it("should log error if Resend fails", async () => {
			const resendError = new Error("Resend API Error");
			mockSend.mockResolvedValue({ data: null, error: resendError }); // Resend SDK might return error in object
			// OR mockSend.mockRejectedValue(resendError); if it throws

			await emailServiceModule.sendSubmissionNotification(
				form,
				submissionData,
				userOwnerEmail
			);
			expect(logger.error).toHaveBeenCalledWith(
				"Error sending submission email via Resend:",
				resendError
			);
		});

		it("should not send if RESEND_API_KEY is missing", async () => {
			delete process.env.RESEND_API_KEY; // Temporarily remove
			// Re-require or re-instantiate the service if it checks env vars at import time
			// For this structure, the check is at the top of the file, so it might already be 'null'
			// A better approach would be for the service to have an isConfigured() method.
			// Forcing a re-import for the test is tricky without specific Jest features for module reloading.
			// Let's assume the check inside sendSubmissionNotification handles the 'resend' object being null.

			// To test this properly, we might need to re-import the module after changing env var
			jest.resetModules(); // Clears module cache
			process.env.RESEND_API_KEY = undefined;
			const freshEmailService = require("../../../src/services/emailService");

			await freshEmailService.sendSubmissionNotification(
				form,
				submissionData,
				userOwnerEmail
			);
			expect(mockSend).not.toHaveBeenCalled();
			expect(logger.warn).toHaveBeenCalledWith(
				expect.stringContaining("Resend SDK not initialized")
			);

			process.env.RESEND_API_KEY = "test-resend-api-key"; // Restore
			jest.resetModules(); // Clean up
		});
	});
	// You would add similar tests for sendVerificationEmail, etc. from the old Nodemailer-based service
	// if you intend to keep that functionality (currently it's commented out or separate)
});