(function () {
    function hideTelegramHomeSection() {
        var wrap = document.getElementById('telegram-home-section');
        if (wrap) {
            wrap.style.display = 'none';
        }
    }

    function showTelegramHomeSection() {
        var wrap = document.getElementById('telegram-home-section');
        if (wrap) {
            wrap.style.display = '';
        }
    }

    function loadTelegramHomePosts() {
        var container = document.getElementById('telegram-posts-container');
        var carousel = document.getElementById('telegram-carousel');
        var meta = document.getElementById('telegram-home-meta');
        var scrollEl = document.getElementById('telegram-scroll');
        var prevBtn = document.getElementById('telegram-prev');
        var nextBtn = document.getElementById('telegram-next');

        if (!container || !carousel) {
            return;
        }

        function escapeHtml(s) {
            if (!s) return '';
            var d = document.createElement('div');
            d.textContent = s;
            return d.innerHTML;
        }

        function captionShort(text, max) {
            max = max || 100;
            if (!text) return 'Telegram gönderisi';
            var t = text.replace(/\s+/g, ' ').trim();
            if (t.length <= max) return t;
            return t.slice(0, max) + '…';
        }

        function timeLabel(iso) {
            if (!iso) return '';
            try {
                var d = new Date(iso);
                if (isNaN(d.getTime())) return '';
                var now = new Date();
                var sec = Math.floor((now - d) / 1000);
                if (sec < 60) return 'Az önce';
                if (sec < 3600) return Math.floor(sec / 60) + ' dk';
                if (sec < 86400) return Math.floor(sec / 3600) + ' sa';
                if (sec < 86400 * 7) return Math.floor(sec / 86400) + ' gün';
                return d.toLocaleDateString('tr-TR', { day: '2-digit', month: 'short' });
            } catch (e) {
                return '';
            }
        }

        var telegramIconSvg = '<svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" role="img" width="1em" height="1em" viewBox="0 0 24 24" fill="currentColor"><path d="M12 2C6.48 2 2 6.48 2 12s4.48 10 10 10s10-4.48 10-10S17.52 2 12 2zm4.64 6.8c-.15 1.58-.8 5.42-1.13 7.19c-.14.75-.42 1-.68 1.03c-.58.05-1.02-.38-1.58-.75c-.88-.58-1.38-.94-2.23-1.5c-.99-.65-.35-1.01.22-1.59c.15-.15 2.71-2.48 2.76-2.69a.2.2 0 0 0-.05-.18c-.06-.05-.14-.03-.21-.02c-.09.02-1.49.95-4.22 2.79c-.4.27-.76.41-1.08.4c-.36-.01-1.04-.2-1.55-.37c-.63-.2-1.12-.31-1.08-.66c.02-.18.27-.36.74-.55c2.92-1.27 4.86-2.11 5.83-2.51c2.78-1.16 3.35-1.36 3.73-1.36c.08 0 .27.02.39.12c.1.08.13.19.14.27c-.01.06.01.24 0 .38z"/></svg>';

        var telegramBrokenImg = 'data:image/svg+xml,' + encodeURIComponent(
            '<svg xmlns="http://www.w3.org/2000/svg" width="360" height="640" viewBox="0 0 360 640"><rect fill="%23229ED9" width="360" height="640"/><circle cx="180" cy="280" r="56" fill="none" stroke="rgba(255,255,255,0.35)" stroke-width="10"/><path fill="rgba(255,255,255,0.9)" d="M148 242l84 54-84 54z"/></svg>'
        );

        function createPostCard(post) {
            var div = document.createElement('div');
            div.className = 'instagram-item';
            div.setAttribute('role', 'group');
            div.setAttribute('aria-roledescription', 'slide');

            var cap = captionShort(post.text);
            var when = timeLabel(post.datetime);
            var imgHtml;
            if (post.image) {
                imgHtml = '<img alt="' + escapeHtml(cap) + '" loading="lazy" width="100" height="100" decoding="async" class="instagram-image" referrerpolicy="no-referrer" src="' + escapeHtml(post.image) + '" style="color:transparent;" data-fallback="' + telegramBrokenImg + '" onerror="if(this.dataset.fallback){this.onerror=null;this.src=this.dataset.fallback;}">';
            } else {
                imgHtml = '<div class="instagram-image telegram-card-placeholder" aria-hidden="true">' + telegramIconSvg + '</div>';
            }

            div.innerHTML =
                '<a target="_blank" rel="noopener noreferrer" href="' + escapeHtml(post.url) + '">' +
                '<div class="instagram-card">' +
                '<div class="section-card-inner">' +
                imgHtml +
                '<div class="instagram-overlay">' +
                '<div class="instagram-caption">' + escapeHtml(cap) + '</div>' +
                '<div class="instagram-icon">' + telegramIconSvg + '</div>' +
                '<div class="instagram-date">' + escapeHtml(when) + '</div>' +
                '</div></div></div></a>';

            return div;
        }

        function initTelegramScroll() {
            if (!scrollEl || !prevBtn || !nextBtn) return;

            var scrollAmount = 320;

            function updateButtonStates() {
                var sl = scrollEl.scrollLeft;
                var maxScroll = scrollEl.scrollWidth - scrollEl.clientWidth;

                if (sl <= 10) {
                    prevBtn.style.opacity = '0';
                    prevBtn.style.pointerEvents = 'none';
                } else {
                    prevBtn.style.opacity = '1';
                    prevBtn.style.pointerEvents = 'auto';
                }

                if (sl >= maxScroll - 10) {
                    nextBtn.style.opacity = '0';
                    nextBtn.style.pointerEvents = 'none';
                } else {
                    nextBtn.style.opacity = '1';
                    nextBtn.style.pointerEvents = 'auto';
                }
            }

            prevBtn.addEventListener('click', function () {
                scrollEl.scrollBy({ left: -scrollAmount, behavior: 'smooth' });
                setTimeout(updateButtonStates, 350);
            });
            nextBtn.addEventListener('click', function () {
                scrollEl.scrollBy({ left: scrollAmount, behavior: 'smooth' });
                setTimeout(updateButtonStates, 350);
            });
            // rAF-throttled scroll handler — max bir güncelleme/frame
            var _tgScrollRaf = null;
            scrollEl.addEventListener('scroll', function () {
                if (_tgScrollRaf) return;
                _tgScrollRaf = requestAnimationFrame(function () {
                    _tgScrollRaf = null;
                    updateButtonStates();
                });
            }, { passive: true });
            updateButtonStates();
        }

        fetch('/ajax/get_telegram_posts.php')
            .then(function (r) { return r.json(); })
            .then(function (data) {
                if (!data.success || !data.data || !data.data.length) {
                    hideTelegramHomeSection();
                    return;
                }

                var metaLink = document.getElementById('telegram-home-meta-link');
                if (data.channel_url && meta && metaLink) {
                    var titleText = (data.channel_title && String(data.channel_title).trim()) ||
                        ('@' + String(data.channel || '').trim());
                    metaLink.href = data.channel_url;
                    metaLink.textContent = titleText;
                    meta.style.display = 'inline-flex';
                }

                container.innerHTML = '';
                data.data.forEach(function (post) {
                    container.appendChild(createPostCard(post));
                });

                showTelegramHomeSection();
                setTimeout(initTelegramScroll, 80);
            })
            .catch(function () {
                hideTelegramHomeSection();
            });
    }

    if (document.readyState === 'loading') {
        document.addEventListener('DOMContentLoaded', loadTelegramHomePosts);
    } else {
        loadTelegramHomePosts();
    }
})();