// TODO: Import necessary modules, e.g., for making HTTP requests (like axios or node-fetch)
// import { IDataObject } from 'n8n-workflow'; // Or other relevant n8n types

/**
 * @namespace SunoApiUtils
 * Utility functions for interacting with the Suno AI API.
 * These functions are placeholders and need to be implemented based on
 * the actual API behavior discovered during research (see docs/dev-log.md).
 */

/**
 * Logs in to the Suno AI service using email and password.
 * This function will likely interact with a login endpoint and store
 * session information (e.g., cookies, tokens) for subsequent requests.
 *
 * @async
 * @memberof SunoApiUtils
 * @param {string} email - The user's email address.
 * @param {string} password - The user's password.
 * @returns {Promise<boolean>} A promise that resolves to true if login is successful, false otherwise.
 * @throws {Error} If login fails or an API error occurs.
 */
export async function loginWithCredentials(email, password) {
	// TODO: Implement actual API call to login endpoint.
	// TODO: Store session token/cookie upon successful login.
	// TODO: Implement error handling based on research from docs/dev-log.md
	console.log('Attempting login for:', email); // Placeholder
	throw new Error('Not implemented: loginWithCredentials');
	// return Promise.resolve(true); // Placeholder
}

/**
 * Retrieves the current session token or authentication cookie.
 * This function should access the stored session information.
 *
 * @async
 * @memberof SunoApiUtils
 * @returns {Promise<string | null>} A promise that resolves to the session token/cookie string, or null if not authenticated.
 */
export async function getSessionToken() {
	// TODO: Implement logic to retrieve stored session token/cookie.
	// TODO: Implement error handling based on research from docs/dev-log.md
	throw new Error('Not implemented: getSessionToken');
	// return Promise.resolve('mock_session_token'); // Placeholder
}

/**
 * Checks if the current session is active/valid and refreshes it if necessary.
 * This might involve making a test API call or using a dedicated refresh token endpoint.
 *
 * @async
 * @memberof SunoApiUtils
 * @returns {Promise<boolean>} A promise that resolves to true if the session is active or refreshed, false otherwise.
 */
export async function refreshSessionIfExpired() {
	// TODO: Implement logic to check session validity (e.g., by calling a protected endpoint).
	// TODO: If session is expired, attempt to refresh it using a refresh token or re-login mechanism.
	// TODO: Implement error handling based on research from docs/dev-log.md
	throw new Error('Not implemented: refreshSessionIfExpired');
	// return Promise.resolve(true); // Placeholder
}

/**
 * Checks if the user is currently authenticated.
 * This could involve checking for a valid session token and/or its expiry.
 *
 * @async
 * @memberof SunoApiUtils
 * @returns {Promise<boolean>} A promise that resolves to true if authenticated, false otherwise.
 */
export async function isAuthenticated() {
	// TODO: Implement logic to check for a valid, non-expired session token/cookie.
	// TODO: May call getSessionToken() and refreshSessionIfExpired() internally.
	// TODO: Implement error handling based on research from docs/dev-log.md
	throw new Error('Not implemented: isAuthenticated');
	// return Promise.resolve(true); // Placeholder
}

/**
 * Submits a prompt to Suno AI to generate music.
 *
 * @async
 * @memberof SunoApiUtils
 * @param {string} promptText - The text prompt describing the desired music.
 * @param {object} [options] - Optional parameters for the generation process.
 * @param {string} [options.style] - Desired style of music.
 * @param {boolean} [options.instrumental] - Whether to generate instrumental music.
 * @param {string} [options.customLyrics] - Custom lyrics to use.
 * @returns {Promise<any>} A promise that resolves with the API response (e.g., job ID for polling).
 * @throws {Error} If the API request fails.
 */
export async function submitPrompt(promptText, options = {}) {
	// TODO: Ensure user is authenticated before making the call.
	// TODO: Implement actual API call to the prompt submission endpoint.
	// TODO: Structure the payload according to API requirements.
	// TODO: Implement error handling based on research from docs/dev-log.md
	console.log('Submitting prompt:', promptText, 'with options:', options); // Placeholder
	throw new Error('Not implemented: submitPrompt');
	// return Promise.resolve({ jobId: 'mock_job_id_123' }); // Placeholder
}

/**
 * Uploads a reference audio track to Suno AI.
 * This might be used for features like "continue track" or style transfer.
 *
 * @async
 * @memberof SunoApiUtils
 * @param {string} filePath - Path to the local audio file.
 * @param {object} [options] - Optional parameters for the upload.
 * @param {string} [options.title] - Title for the reference track.
 * @returns {Promise<any>} A promise that resolves with the API response (e.g., track ID).
 * @throws {Error} If the file upload fails or API error occurs.
 */
export async function uploadReferenceTrack(filePath, options = {}) {
	// TODO: Ensure user is authenticated.
	// TODO: Implement file reading and multipart/form-data request for upload.
	// TODO: Implement error handling based on research from docs/dev-log.md
	console.log('Uploading reference track:', filePath, 'with options:', options); // Placeholder
	throw new Error('Not implemented: uploadReferenceTrack');
	// return Promise.resolve({ referenceTrackId: 'mock_ref_track_456' }); // Placeholder
}

/**
 * Selects a specific voice or instrument for generation.
 * This assumes Suno AI has a concept of selectable voices/instruments.
 *
 * @async
 * @memberof SunoApiUtils
 * @param {string} voiceId - The ID of the voice/instrument to select.
 * @returns {Promise<void>} A promise that resolves when the selection is successful.
 * @throws {Error} If the API request fails.
 */
export async function selectVoice(voiceId) {
	// TODO: Ensure user is authenticated.
	// TODO: Implement API call to select a voice/instrument.
	// TODO: Implement error handling based on research from docs/dev-log.md
	console.log('Selecting voice:', voiceId); // Placeholder
	throw new Error('Not implemented: selectVoice');
	// return Promise.resolve(); // Placeholder
}

/**
 * Polls the status of a generation job.
 *
 * @async
 * @memberof SunoApiUtils
 * @param {string} jobId - The ID of the job to poll.
 * @returns {Promise<any>} A promise that resolves with the job status information (e.g., progress, completion, URLs to tracks).
 * @throws {Error} If the API request fails.
 */
export async function pollJobStatus(jobId) {
	// TODO: Ensure user is authenticated.
	// TODO: Implement API call to get job status. This might need to be called repeatedly.
	// TODO: Implement error handling based on research from docs/dev-log.md
	console.log('Polling job status for:', jobId); // Placeholder
	throw new Error('Not implemented: pollJobStatus');
	// return Promise.resolve({ status: 'completed', trackUrl: 'https://example.com/track.mp3' }); // Placeholder
}

/**
 * Downloads a generated audio track.
 *
 * @async
 * @memberof SunoApiUtils
 * @param {string} trackId - The ID of the track to download.
 * @returns {Promise<any>} A promise that resolves with the audio data (e.g., a Buffer or Stream).
 * @throws {Error} If the download fails or API error occurs.
 */
export async function downloadTrack(trackId) {
	// TODO: Ensure user is authenticated.
	// TODO: Implement API call to download the track file.
	// TODO: Handle binary data response.
	// TODO: Implement error handling based on research from docs/dev-log.md
	console.log('Downloading track:', trackId); // Placeholder
	throw new Error('Not implemented: downloadTrack');
	// return Promise.resolve(Buffer.from('mock_audio_data')); // Placeholder
}

/**
 * Lists previously generated songs by the user.
 *
 * @async
 * @memberof SunoApiUtils
 * @param {object} [options] - Optional parameters for listing songs.
 * @param {number} [options.limit] - Maximum number of songs to retrieve.
 * @param {number} [options.offset] - Offset for pagination.
 * @returns {Promise<any[]>} A promise that resolves with an array of song objects.
 * @throws {Error} If the API request fails.
 */
export async function listPreviousSongs(options = {}) {
	// TODO: Ensure user is authenticated.
	// TODO: Implement API call to list songs.
	// TODO: Implement error handling based on research from docs/dev-log.md
	console.log('Listing previous songs with options:', options); // Placeholder
	throw new Error('Not implemented: listPreviousSongs');
	// return Promise.resolve([{ id: 'song1', title: 'My First Song' }, { id: 'song2', title: 'Another Hit' }]); // Placeholder
}

// Example of how these might be called (for testing/ideation only):
/*
async function main() {
	try {
		const loggedIn = await loginWithCredentials('test@example.com', 'password123');
		if (loggedIn) {
			const token = await getSessionToken();
			console.log('Session token:', token);

			if (await isAuthenticated()) {
				const job = await submitPrompt('Epic orchestral score for a space battle', { style: 'cinematic' });
				console.log('Submitted job:', job.jobId);

				let status;
				do {
					await new Promise(resolve => setTimeout(resolve, 5000)); // Wait 5s
					status = await pollJobStatus(job.jobId);
					console.log('Job status:', status);
				} while (status.status !== 'completed' && status.status !== 'failed');

				if (status.status === 'completed') {
					const audioData = await downloadTrack(status.trackUrl); // Assuming trackUrl is the ID or direct URL
					console.log('Downloaded track data length:', audioData.length);
				}

				const songs = await listPreviousSongs({ limit: 5 });
				console.log('Previous songs:', songs);
			}
		}
	} catch (error) {
		console.error('Suno API Error:', error.message);
	}
}

// main(); // Uncomment to run example (ensure to handle promises correctly if top-level await is not available)
*/