/* Safe chat Markdown: parse tokens, build a restricted DOM, never insert model HTML. */
(()=>{'use strict';
  const tags=new Set(['p','strong','em','s','blockquote','ul','ol','li','h1','h2','h3','h4','h5','h6','table','thead','tbody','tr','th','td','a']);
  let parser;
  function getParser(){
    if(!parser)parser=window.markdownit({html:false,linkify:false,typographer:false,breaks:true});
    return parser;
  }
  function safeHref(value){
    if(typeof value!=='string'||/[\u0000-\u0020\u007f]/.test(value))return null;
    try{const url=new URL(value,location.href);return ['http:','https:','mailto:'].includes(url.protocol)?url.href:null}catch{return null}
  }
  function appendTokens(tokens,parent){
    const stack=[parent];
    const current=()=>stack[stack.length-1];
    const text=value=>current().append(document.createTextNode(value||''));
    for(const token of tokens){
      if(token.hidden)continue;
      if(token.type==='inline'){appendTokens(token.children||[],current());continue}
      if(token.type==='text'||token.type==='html_inline'||token.type==='html_block'){text(token.content);continue}
      if(token.type==='softbreak'||token.type==='hardbreak'){current().append(document.createElement('br'));continue}
      if(token.type==='code_inline'){
        const el=document.createElement('code');el.textContent=token.content;current().append(el);continue;
      }
      if(token.type==='fence'||token.type==='code_block'){
        const pre=document.createElement('pre'),code=document.createElement('code');code.textContent=token.content;pre.append(code);current().append(pre);continue;
      }
      if(token.type==='image'){text(token.content||'图片');continue}
      if(token.type==='hr'){current().append(document.createElement('hr'));continue}
      if(token.nesting===-1){if(stack.length>1)stack.pop();continue}
      if(token.nesting===1){
        const el=document.createElement(tags.has(token.tag)?token.tag:'span');
        if(token.tag==='a'){
          const href=safeHref(token.attrGet('href'));
          if(href){el.href=href;el.target='_blank';el.rel='noopener noreferrer';el.referrerPolicy='no-referrer'}
        }
        if(token.tag==='ol'){
          const start=token.attrGet('start');if(start&&/^\d{1,9}$/.test(start))el.start=Number(start);
        }
        if(token.tag==='th'||token.tag==='td'){
          const align=token.attrGet('style')||'';
          if(/^text-align:(left|center|right)$/.test(align))el.style.textAlign=align.slice(11);
        }
        current().append(el);stack.push(el);continue;
      }
      text(token.content);
    }
  }
  function render(element,source){
    const value=typeof source==='string'?source:'';
    try{
      const fragment=document.createDocumentFragment();
      appendTokens(getParser().parse(value,{}),fragment);
      element.replaceChildren(fragment);element.classList.add('chat-markdown');
    }catch{
      element.textContent=value;element.classList.remove('chat-markdown');
    }
  }
  function toSpeechText(source){
    const root=document.createElement('div');render(root,source);
    const blocks=new Set(['P','LI','H1','H2','H3','H4','H5','H6','BLOCKQUOTE','PRE','TR','UL','OL']);
    function read(node){
      if(node.nodeType===3)return node.nodeValue;
      if(node.nodeName==='BR')return '\n';
      const value=Array.from(node.childNodes,read).join('');
      return value+(blocks.has(node.nodeName)?'\n':node.nodeName==='TD'||node.nodeName==='TH'?'，':'');
    }
    return read(root).trim();
  }
  window.ZhiweiChatMarkdown=Object.freeze({render,toSpeechText});
})();