#include "ctai_parsestring.h"

namespace ctai_parse {

QString parseMathInline(const QString& text) {
    QString result = text;
    QRegularExpression regex("\\$([^\\$]+)\\$");
    result.replace(regex, "<span class='math-inline'>\\1</span>");
    return result;
}

QString parseMathBlock(const QString& text) {
    QString result = text;
    QRegularExpression regex("\\$\\$([^\\$]+)\\$\\$");
    result.replace(regex, "<div class='math-block'>\\1</div>");
    return result;
}

QString parseMathSymbols(const QString& text) {
    QString result = text;
    // 希腊字母
    result.replace("\\alpha", "α");
    result.replace("\\beta", "β");
    result.replace("\\gamma", "γ");
    result.replace("\\delta", "δ");
    result.replace("\\theta", "θ");
    result.replace("\\sigma", "σ");
    
    // 数学运算符
    result.replace("\\sum", "∑");
    result.replace("\\prod", "∏");
    result.replace("\\int", "∫");
    result.replace("\\times", "×");
    result.replace("\\div", "÷");
    result.replace("\\pm", "±");
    
    // 比较符号
    result.replace("\\leq", "≤");
    result.replace("\\geq", "≥");
    result.replace("\\neq", "≠");
    result.replace("\\approx", "≈");
    
    // 常用常数
    result.replace("\\infty", "∞");
    result.replace("\\pi", "π");
    
    return result;
}

QString parseSubSuper(const QString& text) {
    QString result = text;
    result.replace(QRegularExpression("\\^\\{([^\\}]+)\\}"), "<sup>\\1</sup>");
    result.replace(QRegularExpression("\\_\\{([^\\}]+)\\}"), "<sub>\\1</sub>");
    return result;
}

QString parseFraction(const QString& text) {
    QString result = text;
    QRegularExpression regex("\\\\frac\\{([^\\}]+)\\}\\{([^\\}]+)\\}");
    result.replace(regex, 
        "<span class='fraction'>"
        "<span class='numerator'>\\1</span>"
        "<span class='denominator'>\\2</span>"
        "</span>");
    return result;
}

QString parseCodeBlockPython(const QString& text) {
    QString result = text;
    QRegularExpression regex("```python\n([^`]+)```");
    result.replace(regex, 
        "<pre class='python-code'>"
        "<code class='language-python'>\\1</code>"
        "</pre>");
    return result;
}

QString parseCodeBlock(const QString& text) {
    QString result = text;
    QRegularExpression regex("```([^\\n]*)\n([^`]+)```");
    result.replace(regex, 
        "<pre class='code-block'>"
        "<code class='language-\\1'>\\2</code>"
        "</pre>");
    return result;
}

QString parseInlineCode(const QString& text) {
    QString result = text;
    result.replace(QRegularExpression("`([^`]+)`"), "<code>\\1</code>");
    return result;
}

QString parseHeaders(const QString& text) {
    QString result = text;
    result.replace(QRegularExpression("^# (.+)$", QRegularExpression::MultilineOption), 
        "<h1>\\1</h1>");
    result.replace(QRegularExpression("^## (.+)$", QRegularExpression::MultilineOption), 
        "<h2>\\1</h2>");
    result.replace(QRegularExpression("^### (.+)$", QRegularExpression::MultilineOption), 
        "<h3>\\1</h3>");
    return result;
}

QString parseEmphasis(const QString& text) {
    QString result = text;
    result.replace(QRegularExpression("\\*\\*([^\\*]+)\\*\\*"), "<strong>\\1</strong>");
    result.replace(QRegularExpression("\\*([^\\*]+)\\*"), "<em>\\1</em>");
    return result;
}

QString parseLinks(const QString& text) {
    QString result = text;
    result.replace(QRegularExpression("\\[([^\\]]+)\\]\\(([^\\)]+)\\)"), 
        "<a href=\"\\2\">\\1</a>");
    return result;
}

QString parseLists(const QString& text) {
    QString result = text;
    result.replace(QRegularExpression("^- (.+)$", QRegularExpression::MultilineOption), 
        "<li>\\1</li>");
    return result;
}

QString parseLineBreaks(const QString& text) {
    QString result = text;
    result.replace(QRegularExpression("\n"), "<br>");
    return result;
}

QString parseMarkdown(const QString& text) {
    QString result = text;
    
    // 处理数学相关
    result = parseMathBlock(result);
    result = parseMathInline(result);
    result = parseMathSymbols(result);
    result = parseSubSuper(result);
    result = parseFraction(result);
    
    // 处理代码块
    result = parseCodeBlockPython(result);
    result = parseCodeBlock(result);
    result = parseInlineCode(result);
    
    // 处理Markdown基本语法
    result = parseHeaders(result);
    result = parseEmphasis(result);
    result = parseLinks(result);
    result = parseLists(result);
    result = parseLineBreaks(result);
    
    return result;
}

} // namespace ctai_parse