// linkify.js - Convert bare URLs to link cards, video URLs to players
(function() {
    var URL_RE = /(https?:\/\/[^\s一-鿿　-〿＀-￯<>"')\]]+)/g;
    var VIDEO_RE = /\.(mp4|webm|ogg|mov)(\?|$)/i;
    var FAVICON_API = 'https://api.usj.cc/api/favicon?url=';

    function getDomain(url) {
        try { return new URL(url).hostname; } catch (e) { return url; }
    }

    function makeVideo(url) {
        var video = document.createElement('video');
        video.className = 'post-video';
        video.controls = true;
        video.preload = 'metadata';
        video.playsInline = true;
        var source = document.createElement('source');
        source.src = url;
        video.appendChild(source);
        return video;
    }

    function makeCard(url) {
        var domain = getDomain(url);
        var card = document.createElement('a');
        card.className = 'link-card';
        card.href = '/tiaozhuan.html?target=' + btoa(url);
        card.target = '_blank';
        card.rel = 'noopener';
        card.innerHTML = '<img class="link-card-icon" src="' + FAVICON_API + domain + '" alt="" loading="lazy" onerror="this.style.display=\'none\'">' +
            '<span class="link-card-body"><span class="link-card-title">' + domain + '</span>' +
            '<span class="link-card-url">' + url + '</span></span>' +
            '<span class="link-card-arrow">↗</span>';
        return card;
    }

    function linkify(root) {
        var walker = document.createTreeWalker(root, NodeFilter.SHOW_TEXT, null, false);
        var textNodes = [];
        while (walker.nextNode()) {
            var node = walker.currentNode;
            if (node.parentElement && node.parentElement.closest('a, .link-card, code, pre, video, #szh')) continue;
            if (URL_RE.test(node.textContent)) textNodes.push(node);
        }

        textNodes.forEach(function(node) {
            URL_RE.lastIndex = 0;
            var text = node.textContent;
            var parts = [];
            var lastIdx = 0;
            var match;
            while ((match = URL_RE.exec(text)) !== null) {
                if (match.index > lastIdx) {
                    parts.push(document.createTextNode(text.slice(lastIdx, match.index)));
                }
                if (VIDEO_RE.test(match[1])) {
                    parts.push(makeVideo(match[1]));
                } else {
                    parts.push(makeCard(match[1]));
                }
                lastIdx = match.index + match[0].length;
            }
            if (parts.length === 0) return;
            if (lastIdx < text.length) {
                parts.push(document.createTextNode(text.slice(lastIdx)));
            }
            var frag = document.createDocumentFragment();
            parts.forEach(function(p) { frag.appendChild(p); });
            node.parentNode.replaceChild(frag, node);
        });
    }

    function run() {
        var content = document.querySelector('.post-content');
        if (content) linkify(content);
    }

    window.initLinkify = run;

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