/* KaTeX Auto-Render - Local Fallback */
(function() {
    'use strict';
    
    console.warn('KaTeX Auto-Render 本地备用版本 - 功能受限');
    
    window.renderMathInElement = function(element, options) {
        console.warn('KaTeX 自动渲染功能不可用 - 使用备用版本');
        
        options = options || {};
        var delimiters = options.delimiters || [
            {left: "$$", right: "$$", display: true},
            {left: "$", right: "$", display: false},
            {left: "\\(", right: "\\)", display: false},
            {left: "\\[", right: "\\]", display: true}
        ];
        
        if (!element) {
            element = document.body;
        }
        
        // 简单的文本替换处理
        var walker = document.createTreeWalker(
            element,
            NodeFilter.SHOW_TEXT,
            null,
            false
        );
        
        var textNodes = [];
        var node;
        while (node = walker.nextNode()) {
            textNodes.push(node);
        }
        
        textNodes.forEach(function(textNode) {
            var text = textNode.textContent;
            var hasMatch = false;
            
            delimiters.forEach(function(delimiter) {
                if (text.includes(delimiter.left) && text.includes(delimiter.right)) {
                    hasMatch = true;
                }
            });
            
            if (hasMatch) {
                var span = document.createElement('span');
                span.innerHTML = text.replace(/\$([^$]+)\$/g, 
                    '<span class="katex" style="font-style: italic; color: #666;" title="数学公式渲染服务不可用">$1</span>');
                textNode.parentNode.replaceChild(span, textNode);
            }
        });
    };
})();