/**
 * 解析 Markdown 内容
 * @param {String} from
 * @param {Number} max_line 最大行数，默认500
 * @returns {HTMLDivElement}
 * @deprecated
 */
export default function mdParse(from: string, max_line?: number): HTMLElement {
    max_line = max_line || 500;
    const base = document.createElement('div');
    let lines = from.split('\n');
    if (lines.length > max_line) {
        lines = lines.slice(0, max_line);
        lines.push("...");
    }

    let prev = '';
    let child_cont;
    lines.forEach(line => {
        if (line.trim() === '') return;
        let node;
        let spl = line.split(' ');
        let md_flag = spl[0];

        switch (md_flag) {
            // 标题
            case '#':
            case '##':
            case '###':
                if (prev === 'li') {
                    child_cont = null;
                }
                prev = 'h' + (md_flag.length + 1);
                node = document.createElement(prev);
                node.innerText = line.slice(md_flag.length + 1);
                base.append(node);
                return;
            // 列表
            case '-':
                if (prev !== 'li') {
                    child_cont = document.createElement('ul');
                    if (!base.contains(child_cont)) base.append(child_cont);
                }
                prev = 'li';
                node = document.createElement(prev);
                node.innerText = line.slice(2);
                child_cont.append(node);
                return;
        }
        prev = 'p';
        node = document.createElement(prev);
        node.innerText = line.trim();
        base.append(node);
    })
    return base;
}