1.1 --- a/s4-main.js	Tue Oct 26 13:16:29 2021 +0900
     1.2 +++ b/s4-main.js	Wed Oct 27 23:45:01 2021 +0900
     1.3 @@ -616,8 +616,33 @@
     1.4  	    e.preventDefault();
     1.5  	}
     1.6      }
     1.7 -    function textInsert(area, pos, string) {
     1.8 -	
     1.9 +    function textInsert(area, string, pos1, pos2) {
    1.10 +	console.log("str="+string);
    1.11 +	area.setRangeText(string, pos1||area.selectionStart,
    1.12 +			  pos2||pos1||area.selectionStart);
    1.13 +	area.selectionStart += string.length;
    1.14 +    }
    1.15 +    function beginningOfLine(area, pos) {
    1.16 +	pos = pos||area.selectionStart;
    1.17 +	let b = area.value.lastIndexOf("\n", pos);
    1.18 +	if (pos>1 && area.value.charCodeAt(pos)==10)
    1.19 +	    b = area.value.lastIndexOf("\n", pos-1);;
    1.20 +	return b>=0 ? b : 0;
    1.21 +    }
    1.22 +    function isInBeginEnd(area, pos){
    1.23 +	pos = pos||area.selectionStart;
    1.24 +	let bol = beginningOfLine(area, pos);
    1.25 +	let thisline = area.value.substr(bol);
    1.26 +	console.log("curchar="+area.value.charCodeAt(pos));
    1.27 +	console.log("prechar="+area.value.charCodeAt(pos-1));
    1.28 +	console.log("bol="+bol+", thisline="+thisline);
    1.29 +	let match = thisline.search(/\\(begin|end){([A-Za-z]*)/), lm, be;
    1.30 +	if (match >= 0) {
    1.31 +	    lm = RegExp.lastMatch;
    1.32 +	    be = RegExp.$1;
    1.33 +	    return RegExp.$2
    1.34 +	}
    1.35 +	return null;
    1.36      }
    1.37      function helpMarkdownBrace(e) {
    1.38  	if (!mathjax) return;
    1.39 @@ -629,14 +654,32 @@
    1.40  	    if (beg >= 0) {
    1.41  		let env = text.substr(beg).search(/\\begin{(.*?)}/);
    1.42  		if (env >= 0) {
    1.43 -		    let endenv = "{"+RegExp.$1+"}";
    1.44 -		    area.setRangeText(endenv, pos, pos);
    1.45 -		    area.selectionStart += endenv.length;
    1.46 +		    textInsert(area, "{"+RegExp.$1+"}", pos);
    1.47  		    e.preventDefault();
    1.48  		}
    1.49  	    }
    1.50  	}
    1.51      }
    1.52 +    function helpMarkdownBraceClose(e) {
    1.53 +	if (!mathjax) return;
    1.54 +	let area = e.target, pos = area.selectionStart, text = area.value,
    1.55 +	    begin = "\\begin", end = "\\end";
    1.56 +	if (text.substr(pos).startsWith("}")) {
    1.57 +	    area.setRangeText("", pos, pos+1);
    1.58 +	    // e.preventDefault();
    1.59 +	}
    1.60 +	let inbegend = isInBeginEnd(area, pos);
    1.61 +	let nextendpos = text.substr(pos).indexOf("\\end{");
    1.62 +	let nextcurend = text.substr(pos).indexOf("\\end{"+inbegend+"}");
    1.63 +	console.log("ib="+inbegend+", nepos="+nextendpos+", ncur="+nextcurend);
    1.64 +	if (nextcurend<0  || nextendpos!=nextcurend) {
    1.65 +	    area.setRangeText("}\n\n\\end{"+inbegend+"}", pos, pos);
    1.66 +	    area.selectionStart = pos+2;
    1.67 +	    e.preventDefault();
    1.68 +	}
    1.69 +	console.log(inbegend);
    1.70 +	
    1.71 +    }
    1.72      function helpMarkdownPreview(area) {
    1.73  	if (!mathjax) {
    1.74  	    alert("no"+e.target)
    1.75 @@ -677,6 +720,7 @@
    1.76  	case "(":  helpMarkdownParen(e); break;
    1.77  	case "p":  if (e.metaKey) helpMarkdownPreview(e.target); break;
    1.78  	case "{":  helpMarkdownBrace(e); break;
    1.79 +	case "}":  helpMarkdownBraceClose(e); break;
    1.80  	}
    1.81      }
    1.82      /* Init event listeners */