document.addEventListener('DOMContentLoaded', () => {
    const gallery = document.getElementById('photo-gallery');
    const searchInput = document.getElementById('searchInput');
    const filterRows = document.querySelector('.filter-rows');
    let filterBtns = Array.from(document.querySelectorAll('.filter-btn'));
    const modal = document.getElementById('image-modal');
    const modalImg = document.getElementById('modal-image-src');
    const modalCaption = document.getElementById('modal-caption');
    const modalCaptionTags = document.getElementById('modal-caption-tags');
    const modalCloseBtn = modal.querySelector('.modal-close-btn') || modal.querySelector('.delete');
    const modalBackground = modal.querySelector('.modal-background');
    const resultCountEl = document.getElementById('result-count');
    const noResults = document.getElementById('no-results');
    const isTouchDevice = 'ontouchstart' in window || (navigator.maxTouchPoints || 0) > 0;
    const topButton = document.getElementById('top');

    const fallbackPhotos = [
        {
            path: '../assets/pics/gallery/classic/20230617_131551.webp',
            caption: "20' Classic Arch",
            tags: ['arch', 'classic', 'outdoor', 'wedding']
        },
        {
            path: '../assets/pics/gallery/classic/_Photos_20241207_083534.webp',
            caption: 'Classic Columns',
            tags: ['columns', 'classic', 'indoor', 'corporate', 'black-tie']
        },
        {
            path: '../assets/pics/gallery/centerpiece/20230108_112718.jpg}.webp',
            caption: 'Cocktail Arrangements',
            tags: ['centerpiece', 'cocktail', 'tablescape', 'baby-shower']
        },
        {
            path: '../assets/pics/gallery/organic/20241121_200047~2.jpg',
            caption: 'Organic Garland',
            tags: ['organic', 'garland', 'outdoor', 'birthday']
        },
        {
            path: '../assets/pics/gallery/organic/20250202_133930~2.jpg',
            caption: 'Organic Garland (Pastel)',
            tags: ['organic', 'garland', 'pastel']
        }
    ];
    let photos = [];
    let tagMeta = { labels: {}, tags: [], aliases: {} };
    const tagLabel = (slug) => {
        if (!slug) return '';
        if (tagMeta.labels && tagMeta.labels[slug]) return tagMeta.labels[slug];
        return slug.replace(/-/g, ' ').replace(/\b\w/g, c => c.toUpperCase());
    };

    const normalizeTags = (tags) => {
        if (Array.isArray(tags)) return tags;
        if (typeof tags === 'string') {
            return tags.split(',').map(tag => tag.trim()).filter(Boolean);
        }
        return [];
    };
    const slugifyTag = (value) => String(value || '')
        .toLowerCase()
        .replace(/[^a-z0-9]+/g, '-')
        .replace(/^-+|-+$/g, '');
    const resolveTagSlug = (value) => {
        const raw = String(value || '').trim();
        if (!raw) return '';
        const lowerRaw = raw.toLowerCase();
        const aliases = tagMeta.aliases || {};
        if (aliases[lowerRaw]) {
            return aliases[lowerRaw];
        }
        const labels = tagMeta.labels || {};
        for (const [slug, label] of Object.entries(labels)) {
            if (label && label.toLowerCase() === lowerRaw) {
                return slug;
            }
        }
        return slugifyTag(raw) || lowerRaw;
    };

    const apiBaseCandidates = (() => {
        const protocol = window.location.protocol;
        const host = window.location.hostname;
        const hints = [
            window.GALLERY_API_URL || '',
            'https://photobackend.beachpartyballoons.com',
            `${protocol}//${host}:5000`,
            `${protocol}//${host}:5001`,
        ];
        // Remove duplicates/empties
        return [...new Set(hints.filter(Boolean))];
    })();

    let activeApiBase = '';

    const fetchWithTimeout = async (url, timeoutMs = 4000) => {
        const controller = new AbortController();
        const timer = setTimeout(() => controller.abort(), timeoutMs);
        try {
            return await fetch(url, { signal: controller.signal });
        } finally {
            clearTimeout(timer);
        }
    };

    async function fetchTagMetadata(baseUrl) {
        if (!baseUrl) return;
        try {
            const response = await fetchWithTimeout(`${baseUrl}/photos/tags`, 3000);
            if (!response.ok) return;
            const data = await response.json();
            tagMeta = { labels: {}, tags: [], aliases: {}, ...data };
        } catch (err) {
            // Metadata is optional; fall back to raw tag text if unavailable.
        }
    }

    async function fetchPhotos() {
        try {
            let data = null;
            for (const base of apiBaseCandidates) {
                try {
                    const response = await fetchWithTimeout(`${base}/photos`, 3500);
                    if (!response.ok) continue;
                    data = await response.json();
                    activeApiBase = base;
                    await fetchTagMetadata(activeApiBase);
                    break;
                } catch (err) {
                    // Try the next candidate quickly; don't block the UI.
                    continue;
                }
            }
            photos = Array.isArray(data) && data.length ? data : fallbackPhotos;
            rebuildFilterButtons();
        } catch (error) {
            console.error('Error fetching photos:', error);
            photos = fallbackPhotos;
            rebuildFilterButtons();
        }
        const hashTag = getHashTag();
        if (hashTag) {
            applyTagFilter(hashTag, false);
        } else {
            applyTagFilter('all', false);
        }
    }

    function updateResultCount(count) {
        if (!resultCountEl) return;
        const total = photos.length;
        const totalText = total ? `${total}` : '0';
        const countText = count !== undefined ? `${count}` : totalText;
        if (count === 0) {
            resultCountEl.innerHTML = `<span>${countText}</span> photos shown • ${totalText} total`;
            return;
        }
        resultCountEl.innerHTML = count === total
            ? `<span>${countText}</span> photos on display`
            : `<span>${countText}</span> shown • ${totalText} total`;
    }

    function attachFilterListeners() {
        filterBtns.forEach(btn => {
            btn.addEventListener('click', () => {
                const tag = btn.dataset.tag;
                applyTagFilter(tag, true);
            });
        });
    }

    function rebuildFilterButtons() {
        if (!filterRows) return;
        const tagCounts = {};
        photos.forEach(photo => {
            normalizeTags(photo.tags).forEach(tag => {
                tagCounts[tag] = (tagCounts[tag] || 0) + 1;
            });
        });
        const sorted = Object.entries(tagCounts)
            .filter(([, count]) => count > 1)
            .sort((a, b) => b[1] - a[1] || tagLabel(a[0]).localeCompare(tagLabel(b[0])));

        const buttons = [`<div class="control"><button class="button filter-btn is-active" data-tag="all">All</button></div>`];
        sorted.forEach(([slug, count]) => {
            const label = `${tagLabel(slug)}${count ? ` (${count})` : ''}`;
            buttons.push(`<div class="control"><button class="button filter-btn" data-tag="${slug}">${label}</button></div>`);
        });

        const rows = [];
        const maxPerRow = 7;
        const maxRows = 2;
        const maxButtons = maxPerRow * maxRows;
        const limitedButtons = buttons.slice(0, maxButtons);
        for (let i = 0; i < limitedButtons.length; i += maxPerRow) {
            rows.push(`<div class="filter-row">${buttons.slice(i, i + 7).join('')}</div>`);
        }
        filterRows.innerHTML = rows.join('');
        filterBtns = Array.from(filterRows.querySelectorAll('.filter-btn'));
        attachFilterListeners();
    }

    function renderFlatGallery(photoArray) {
        gallery.innerHTML = ''; // Clear skeleton or old photos
        updateResultCount(photoArray.length);

        if (photoArray.length === 0) {
            if (noResults) {
                gallery.appendChild(noResults);
                noResults.style.display = 'block';
            }
            return;
        }
        
        if (noResults) {
            noResults.style.display = 'none';
        }
        
        photoArray.forEach((photo, idx) => {
            const resolveUrl = (p) => {
                if (typeof p !== 'string') return '';
                if (p.startsWith('http') || p.startsWith('assets') || p.startsWith('/assets') || p.startsWith('../assets')) return p;
                const base = activeApiBase
                    || 'https://photobackend.beachpartyballoons.com'
                    || `${window.location.protocol}//${window.location.hostname}:5000`;
                const path = p.startsWith('/') ? p.slice(1) : p;
                return `${base.replace(/\/$/, '')}/${path}`;
            };
            const src = resolveUrl(photo.path);
            const srcset = photo.variants
                ? [
                    photo.variants.thumb ? `${resolveUrl(photo.variants.thumb)} 640w` : null,
                    photo.variants.medium ? `${resolveUrl(photo.variants.medium)} 1200w` : null,
                    src ? `${src} 2000w` : null
                ].filter(Boolean).join(', ')
                : '';
            const photoTags = normalizeTags(photo.tags);
            const photoCard = document.createElement('div');
            photoCard.className = 'gallery-item';
            const tagBadges = photoTags
                .map(tag => `<span class="tag-chip" data-tag="${tag}"><i class="fa-solid fa-wand-magic-sparkles"></i>${tagLabel(tag)}</span>`)
                .join('');
            photoCard.innerHTML = `
                <div class="gallery-photo">
                    <img loading="lazy" ${srcset ? `srcset="${srcset}" sizes="(min-width: 1024px) 33vw, (min-width: 768px) 45vw, 90vw"` : ''} src="${src}" alt="${photo.caption}" data-caption="${photo.caption}" data-tags="${photoTags.join(',')}" data-full-src="${src}" decoding="async">
                </div>
                <div class="gallery-overlay">
                    <div class="overlay-bottom">
                        <p class="overlay-title">${photo.caption}</p>
                        <div class="overlay-tags" aria-label="Tags for ${photo.caption}">${tagBadges}</div>
                    </div>
                </div>
            `;
            gallery.appendChild(photoCard);
            setTimeout(() => requestAnimationFrame(() => photoCard.classList.add('is-visible')), idx * 70);
            
            const imgEl = photoCard.querySelector('img');
            imgEl.addEventListener('click', (e) => {
                const card = e.currentTarget.closest('.gallery-item');
                if (isTouchDevice && card) {
                    if (!card.classList.contains('touch-active')) {
                        card.classList.add('touch-active');
                        setTimeout(() => card.classList.remove('touch-active'), 2200);
                        return;
                    }
                }
                openModal(e.target);
                if (card) card.classList.remove('touch-active');
            });

            const tagChips = photoCard.querySelectorAll('.tag-chip');
            tagChips.forEach(chip => {
                chip.addEventListener('click', (e) => {
                    e.stopPropagation();
                    const tagText = chip.dataset.tag || '';
                    applyTagFilter(tagText, true);
                });
            });
        });
    }

    function filterPhotos() {
        const searchTerm = searchInput.value.toLowerCase();
        const normalizedSearch = resolveTagSlug(searchTerm);
        // Deactivate tag buttons when searching
        filterBtns.forEach(btn => btn.classList.remove('is-active'));
        if (searchTerm) {
            const filteredPhotos = photos.filter(photo => {
                const photoTags = normalizeTags(photo.tags);
                const captionMatch = photo.caption.toLowerCase().includes(searchTerm);
                const tagMatch = photoTags.some(tag => {
                    const label = tagLabel(tag).toLowerCase();
                    return tag.toLowerCase().includes(searchTerm)
                        || label.includes(searchTerm)
                        || (normalizedSearch && tag.toLowerCase() === normalizedSearch);
                });
                return captionMatch || tagMatch;
            });
            renderFlatGallery(filteredPhotos);
        } else {
            renderFlatGallery(photos);
            // Reactivate 'All' button if search is cleared
            const allBtn = document.querySelector('.filter-btn[data-tag="all"]');
            if (allBtn) allBtn.classList.add('is-active');
        }
    }

    function setActiveFilterButton(tag) {
        filterBtns.forEach(btn => btn.classList.toggle('is-active', btn.dataset.tag === tag));
    }

    function setHashTag(tag) {
        const url = new URL(window.location.href);
        if (!tag || tag === 'all') {
            url.hash = '';
        } else {
            url.hash = encodeURIComponent(tag);
        }
        history.replaceState(null, '', url);
    }

    function filterByTag(tag, updateHash = true) {
        searchInput.value = '';
        const slug = resolveTagSlug(tag);
        if (!slug || slug === 'all') {
            renderFlatGallery(photos);
            setActiveFilterButton('all');
            if (updateHash) setHashTag('');
            return;
        }
        const filteredPhotos = photos.filter(photo => {
            const photoTags = normalizeTags(photo.tags);
            return photoTags.some(t => t.toLowerCase() === slug);
        });
        renderFlatGallery(filteredPhotos);
        setActiveFilterButton(slug);
        if (updateHash) setHashTag(slug);
    }

    function getHashTag() {
        const hash = window.location.hash || '';
        if (!hash) return '';
        return resolveTagSlug(decodeURIComponent(hash.replace(/^#/, '')).trim());
    }

    function applyTagFilter(tag, updateHash = true) {
        filterByTag(tag, updateHash);
    }
    
    function openModal(imageElement) {
        const rect = imageElement.getBoundingClientRect();
        const centerX = window.innerWidth / 2;
        const centerY = window.innerHeight / 2;
        const imgCenterX = rect.left + rect.width / 2;
        const imgCenterY = rect.top + rect.height / 2;
        const translateX = imgCenterX - centerX;
        const translateY = imgCenterY - centerY;
        const scaleStartRaw = Math.max(
            rect.width / (window.innerWidth * 0.8),
            rect.height / (window.innerHeight * 0.8),
            0.55
        );
        const scaleStart = Math.min(Math.max(scaleStartRaw, 0.72), 0.96);
        document.documentElement.style.setProperty('--modal-img-translate-x', `${translateX}px`);
        document.documentElement.style.setProperty('--modal-img-translate-y', `${translateY}px`);
        document.documentElement.style.setProperty('--modal-img-scale', scaleStart.toFixed(3));
        modalImg.src = imageElement.dataset.fullSrc || imageElement.src;
        modalCaption.textContent = imageElement.dataset.caption;
        if (modalCaptionTags) {
            const tags = (imageElement.dataset.tags || '').split(',').filter(Boolean);
            modalCaptionTags.innerHTML = tags.map(t => `<span class="tag-chip" data-tag="${t}"><i class="fa-solid fa-wand-magic-sparkles"></i>${tagLabel(t)}</span>`).join('');
            const chips = modalCaptionTags.querySelectorAll('.tag-chip');
            chips.forEach(chip => {
                chip.addEventListener('click', (e) => {
                    e.stopPropagation();
                    const tagText = chip.dataset.tag || '';
                    applyTagFilter(tagText, true);
                    closeModal();
                });
            });
        }
        modal.classList.remove('show-bg');
        modal.classList.add('chrome-hidden');
        modal.classList.add('is-active');
        document.documentElement.classList.add('is-clipped');
        document.body.classList.add('modal-open');
        if (topButton) topButton.style.display = 'none';
        // Fade in chrome and background immediately after paint
        requestAnimationFrame(() => {
            modal.classList.add('show-bg');
            modal.classList.remove('chrome-hidden');
        });
    }

    function closeModal() {
        modal.classList.remove('is-active');
        modal.classList.remove('show-bg');
        modal.classList.remove('chrome-hidden');
        document.documentElement.classList.remove('is-clipped');
        document.body.classList.remove('modal-open');
        document.documentElement.style.removeProperty('--modal-img-translate-x');
        document.documentElement.style.removeProperty('--modal-img-translate-y');
        document.documentElement.style.removeProperty('--modal-img-scale');
        if (topButton) {
            const shouldShow = document.body.scrollTop > 130 || document.documentElement.scrollTop > 130;
            topButton.style.display = shouldShow ? 'block' : 'none';
        }
    }

    searchInput.addEventListener('keyup', filterPhotos);

    if (modalCloseBtn) modalCloseBtn.addEventListener('click', closeModal);
    modalBackground.addEventListener('click', closeModal);

    function renderSkeletonLoader() {
        gallery.innerHTML = ''; // Clear gallery
        for (let i = 0; i < 8; i++) {
            const skeletonItem = document.createElement('div');
            skeletonItem.className = 'skeleton-item';
            gallery.appendChild(skeletonItem);
        }
    }

    renderSkeletonLoader();
    window.addEventListener('hashchange', () => {
        const tag = getHashTag() || 'all';
        applyTagFilter(tag, false);
    });

    fetchPhotos();
});