// screenLockManager.js - Manages screen wake lock to prevent screen from turning off
// Uses the Screen Wake Lock API: https://developer.mozilla.org/en-US/docs/Web/API/Screen_Wake_Lock_API

let wakeLock = null;
let isLockEnabled = false;

/**
 * Requests a screen wake lock to prevent the screen from turning off
 * @returns {Promise<boolean>} - True if wake lock was acquired successfully
 */
export async function acquireWakeLock() {
    if (!isScreenWakeLockSupported()) {
        console.warn('[ScreenLockManager] Screen Wake Lock API not supported in this browser');
        return false;
    }

    try {
        // Release any existing wake lock first
        await releaseWakeLock();
        
        // Request a new wake lock
        wakeLock = await navigator.wakeLock.request('screen');
        isLockEnabled = true;
        
        console.log('[ScreenLockManager] Screen Wake Lock acquired');
        
        // Add event listeners to reacquire the lock when needed
        setupWakeLockListeners();
        
        return true;
    } catch (error) {
        console.error('[ScreenLockManager] Error acquiring wake lock:', error);
        isLockEnabled = false;
        return false;
    }
}

/**
 * Releases the screen wake lock if one is active
 * @returns {Promise<boolean>} - True if wake lock was released successfully
 */
export async function releaseWakeLock() {
    if (!wakeLock) {
        return true; // No wake lock to release
    }
    
    try {
        await wakeLock.release();
        wakeLock = null;
        isLockEnabled = false;
        console.log('[ScreenLockManager] Screen Wake Lock released');
        return true;
    } catch (error) {
        console.error('[ScreenLockManager] Error releasing wake lock:', error);
        return false;
    }
}

/**
 * Checks if the Screen Wake Lock API is supported in this browser
 * @returns {boolean} - True if supported
 */
export function isScreenWakeLockSupported() {
    return 'wakeLock' in navigator && 'request' in navigator.wakeLock;
}

/**
 * Returns the current status of the wake lock
 * @returns {boolean} - True if wake lock is currently active
 */
export function isWakeLockActive() {
    return isLockEnabled && wakeLock !== null;
}

/**
 * Sets up event listeners to reacquire the wake lock when needed
 * (e.g., when the page becomes visible again after being hidden)
 */
function setupWakeLockListeners() {
    // When the page becomes visible again, reacquire the wake lock
    document.addEventListener('visibilitychange', handleVisibilityChange);
    
    // When the screen orientation changes, reacquire the wake lock
    if ('screen' in window && 'orientation' in window.screen) {
        window.screen.orientation.addEventListener('change', handleOrientationChange);
    }
}

/**
 * Handles visibility change events to reacquire wake lock when page becomes visible
 */
async function handleVisibilityChange() {
    if (isLockEnabled && document.visibilityState === 'visible') {
        // Only try to reacquire if we previously had a lock
        await acquireWakeLock();
    }
}

/**
 * Handles orientation change events to reacquire wake lock
 */
async function handleOrientationChange() {
    if (isLockEnabled) {
        // Some devices may release the wake lock on orientation change
        await acquireWakeLock();
    }
}

/**
 * Initializes the screen lock manager
 * @param {Object} options - Configuration options
 * @param {boolean} options.autoAcquire - Whether to automatically acquire wake lock on init
 * @returns {Promise<boolean>} - True if initialization was successful
 */
export async function initScreenLockManager(options = {}) {
    const { autoAcquire = true } = options; // Default to true - automatically acquire on init
    
    // Check for support
    const isSupported = isScreenWakeLockSupported();
    console.log(`[ScreenLockManager] Screen Wake Lock API ${isSupported ? 'is' : 'is not'} supported`);
    
    // Automatically acquire wake lock if supported (now default behavior)
    if (autoAcquire && isSupported) {
        return await acquireWakeLock();
    }
    
    return isSupported;
}