/**
 * View Transitions Helper - Admin Interface
 *
 * Helper-Funktionen für View Transitions API.
 * Baseline 2023: View Transitions API ist Baseline Newly available.
 */

/**
 * Check if View Transitions are supported
 */
export function supportsViewTransitions() {
    return 'startViewTransition' in document;
}

/**
 * Start View Transition for Admin Navigation
 */
export function transitionNavigation(callback) {
    if (!supportsViewTransitions()) {
        callback();
        return;
    }

    document.startViewTransition(() => {
        callback();
    });
}

/**
 * Start View Transition for Admin Content Updates
 */
export function transitionContentUpdate(callback) {
    if (!supportsViewTransitions()) {
        callback();
        return;
    }

    const transition = document.startViewTransition(() => {
        callback();
    });

    return transition;
}

/**
 * Start View Transition for Popover
 */
export function transitionPopover(popoverElement, callback) {
    if (!supportsViewTransitions()) {
        callback();
        return;
    }

    // Set view-transition-name for this specific popover
    const originalName = popoverElement.style.viewTransitionName;
    popoverElement.style.viewTransitionName = `admin-popover-${popoverElement.id}`;

    const transition = document.startViewTransition(() => {
        callback();
    });

    transition.finished.finally(() => {
        // Restore original name
        if (originalName) {
            popoverElement.style.viewTransitionName = originalName;
        } else {
            popoverElement.style.viewTransitionName = '';
        }
    });

    return transition;
}

/**
 * Initialize View Transitions for Admin Navigation Links
 */
export function initAdminNavigationTransitions() {
    if (!supportsViewTransitions()) {
        return;
    }

    // Handle navigation links
    document.querySelectorAll('.admin-nav a[href]').forEach(link => {
        link.addEventListener('click', (e) => {
            const href = link.getAttribute('href');
            
            // Only handle internal links
            if (href && !href.startsWith('http') && !href.startsWith('#')) {
                e.preventDefault();
                
                transitionNavigation(() => {
                    window.location.href = href;
                });
            }
        });
    });
}

/**
 * Initialize View Transitions for Popover Toggles
 */
export function initPopoverTransitions() {
    if (!supportsViewTransitions()) {
        return;
    }

    document.querySelectorAll('[popovertarget]').forEach(trigger => {
        const popoverId = trigger.getAttribute('popovertarget');
        const popover = document.getElementById(popoverId);
        
        if (popover) {
            popover.addEventListener('toggle', (e) => {
                const isOpen = popover.matches(':popover-open');
                
                transitionPopover(popover, () => {
                    // Transition is handled by browser
                });
            });
        }
    });
}

/**
 * Initialize all View Transitions
 */
export function initViewTransitions() {
    initAdminNavigationTransitions();
    initPopoverTransitions();
}

// Auto-initialize if DOM is ready
if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', initViewTransitions);
} else {
    initViewTransitions();
}