bool isUnorderedList(std::string &input){
    if ((input[0] == '*' || input[0] == '+' || input[0] == '-') && input[1] == ' ') {
        return true;
    }
    else {
        return false;
    }

}

bool isQuote(std::string &input) {
    if (input[0] == '>' && input[1] == ' ') {
        return true;
    }
    else {
        return false;
    }
}
bool isOrderedList(std::string &input) {
    if (isdigit(input[0]) && input[1] == '.' && input[2] == ' ') {
        return true;
    }
    else {
        return false;
    }
}
bool isHerLine(std::string &input) {
    std::string::iterator i;
    for (i = input.begin(); i != input.end(); i++) {
        if (*i != '-') {
            break;
        }
    }
    if (i == input.end() && input.size() >= 3) {
        return true;
    }
    else {
        return false;
    }
}
codeType isCodeBlock(std::string &input){
    codeType codeSym;
    if (input == "```python") {
        codeSym = codeType::PYTHON;
    }
    else if (input == "```c++") {
        codeSym = codeType::CPP;
    }
    else {
        codeSym = codeType::WRONG;
    }
    return codeSym;
}

// handle with link sup img
std::string regex(std::string &input) {

    // \[*](*),link
    std::regex re_link("/\\[(.*)\\]\\((.*)\\)");
    input=std::regex_replace(input, re_link, "<a href=\"$2\" target=\"_blank\">$1</a>");
    
    std::regex re_sup("\\[(.*)\\]\\[(.*)\\]");
    input = std::regex_replace(input, re_sup, "$1<sup>$2</sup>");

    std::regex re_img("!\\[(.*)\\]\\((.*)\\)");
    input = std::regex_replace(input, re_img, "&nbsp<img src=\"$2\" align=\"middle\">");
    return input;
}

enum class stateBlock{
    BEGIN,
    IN,
    END,
};

enum class codeType {
    PYTHON,
    CPP,
    WRONG
};
extern codeType code;

std::string parse(std::string &input) {
    std::string temp= input;
    if (input.empty()) {
        return "";
    }
    if (state == stateBlock::IN) {
        std::regex re_blank("\\s");
        std::regex re_lt("<");
        temp = std::regex_replace(temp, re_blank, "&nbsp");
        temp = std::regex_replace(temp, re_lt, "&lt");
    }

    // 块内
    if (preHandle(temp) == 0) {
        temp = setColor(temp);
        temp.insert(0, "<p>");
        temp+="</p>";
        return temp;
    }

    currentLineOrder = false;
    temp = token(temp);
    temp = regex(temp);
    if (input[0] == '#'&& input[1] == ' ') {
        temp=handleTitle(input, 1);
    }
    else if (input[0] == '#'&& input[1] == '#' &&input[2]==' ') {
        temp=handleTitle(input, 2);
    }
    else if (input[0] == '#'&& input[1] == '#' &&input[2] == '#' && input[3]==' ') {
        temp=handleTitle(input, 3);
    }
    
    else if (isUnorderedList(input) ){
        temp = handleUnorderedList(temp);
    }
    else if (isQuote(input)) {
        temp = handleQuote(temp);
    }
    else if (isOrderedList(input)) {
        temp = handleOrderedList(temp);
    }
    else if (isHerLine(input)) {
        temp = handleHerLine();
    }
    else {
        temp += "</br>";
    }
    closeOrderList(temp);
    return temp;
}