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howiemnet/highlighter.html

Created May 17, 2023 14:06
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Hacky JS file hilighter - takes a URL to a JS file (in the querystring - add ?file=https://url.to/my/javascript/file.js) and renders it nicely... -ish.
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highlighter.html
<!DOCTYPE html>
<html>
<body>
<div style="font-family: sans-serif; font-size: large; width: 100%; padding: 10px; margin:0 0 30px 0; border: 2px solid black;" id="titlebar"></div>
<div id="myDiv">
</div>
<script>
// h quick util: takes a querystring URL - ?file=URL_to_JS_file and renders out as hilighted JS
const params = new Proxy(new URLSearchParams(window.location.search), { get: (searchParams, prop) => searchParams.get(prop), });
function getText(){
// read text from URL location
var request = new XMLHttpRequest();
var sourceURL = params.file;
document.getElementById("titlebar").innerHTML = "h's hacky syntax hilighter - file: <strong>"+sourceURL+"</strong>";
request.open('GET', sourceURL, true);
request.send(null);
request.onreadystatechange = function () {
if (request.readyState === 4 && request.status === 200) {
var type = request.getResponseHeader('Content-Type');
if (type.indexOf("javascript") !== 1) {
var str = request.responseText;
// quick replacements to fix JS file formatting when thrown into
// an HTML renderer.
//
// In order, replace tabs, spaces (so they don't get collapsed), angle brackets, newlines:
str = str.replace(/\t/g, '&nbsp;&nbsp;&nbsp;&nbsp;').replace(/ /g, '&nbsp;').replace(/</g, "&lt;").replace(/>/g, "&gt;").replace(/(?:\r\n|\r|\n)/g, '<br>');
var el = document.getElementById("myDiv");
el.innerHTML = str;
w3CodeColor(el,"js");
}
}
}
}
getText();
function w3CodeColor(elmnt, mode) {
var lang = (mode || "html");
var elmntObj = (document.getElementById(elmnt) || elmnt);
var elmntTxt = elmntObj.innerHTML;
var tagcolor = "mediumblue";
var tagnamecolor = "brown";
var attributecolor = "red";
var attributevaluecolor = "mediumblue";
var commentcolor = "green";
var cssselectorcolor = "brown";
var csspropertycolor = "red";
var csspropertyvaluecolor = "mediumblue";
var cssdelimitercolor = "black";
var cssimportantcolor = "red";
var jscolor = "black";
var jskeywordcolor = "mediumblue";
var jsstringcolor = "brown";
var jsnumbercolor = "red";
var jspropertycolor = "black";
elmntObj.style.fontFamily = "Consolas,'Courier New', monospace";
if (!lang) {lang = "html"; }
if (lang == "html") {elmntTxt = htmlMode(elmntTxt);}
if (lang == "css") {elmntTxt = cssMode(elmntTxt);}
if (lang == "js") {elmntTxt = jsMode(elmntTxt);}
elmntObj.innerHTML = elmntTxt;
function extract(str, start, end, func, repl) {
var s, e, d = "", a = [];
while (str.search(start) > -1) {
s = str.search(start);
e = str.indexOf(end, s);
if (e == -1) {e = str.length;}
if (repl) {
a.push(func(str.substring(s, e + (end.length))));
str = str.substring(0, s) + repl + str.substr(e + (end.length));
} else {
d += str.substring(0, s);
d += func(str.substring(s, e + (end.length)));
str = str.substr(e + (end.length));
}
}
this.rest = d + str;
this.arr = a;
}
function htmlMode(txt) {
var rest = txt, done = "", php, comment, angular, startpos, endpos, note, i;
comment = new extract(rest, "&lt;!--", "--&gt;", commentMode, "W3HTMLCOMMENTPOS");
rest = comment.rest;
while (rest.indexOf("&lt;") > -1) {
note = "";
startpos = rest.indexOf("&lt;");
if (rest.substr(startpos, 9).toUpperCase() == "&LT;STYLE") {note = "css";}
if (rest.substr(startpos, 10).toUpperCase() == "&LT;SCRIPT") {note = "javascript";}
endpos = rest.indexOf("&gt;", startpos);
if (endpos == -1) {endpos = rest.length;}
done += rest.substring(0, startpos);
done += tagMode(rest.substring(startpos, endpos + 4));
rest = rest.substr(endpos + 4);
if (note == "css") {
endpos = rest.indexOf("&lt;/style&gt;");
if (endpos > -1) {
done += cssMode(rest.substring(0, endpos));
rest = rest.substr(endpos);
}
}
if (note == "javascript") {
endpos = rest.indexOf("&lt;/script&gt;");
if (endpos > -1) {
done += jsMode(rest.substring(0, endpos));
rest = rest.substr(endpos);
}
}
}
rest = done + rest;
for (i = 0; i < comment.arr.length; i++) {
rest = rest.replace("W3HTMLCOMMENTPOS", comment.arr[i]);
}
return rest;
}
function tagMode(txt) {
var rest = txt, done = "", startpos, endpos, result;
while (rest.search(/(\s|<br>)/) > -1) {
startpos = rest.search(/(\s|<br>)/);
endpos = rest.indexOf("&gt;");
if (endpos == -1) {endpos = rest.length;}
done += rest.substring(0, startpos);
done += attributeMode(rest.substring(startpos, endpos));
rest = rest.substr(endpos);
}
result = done + rest;
result = "<span style=color:" + tagcolor + ">&lt;</span>" + result.substring(4);
if (result.substr(result.length - 4, 4) == "&gt;") {
result = result.substring(0, result.length - 4) + "<span style=color:" + tagcolor + ">&gt;</span>";
}
return "<span style=color:" + tagnamecolor + ">" + result + "</span>";
}
function attributeMode(txt) {
var rest = txt, done = "", startpos, endpos, singlefnuttpos, doublefnuttpos, spacepos;
while (rest.indexOf("=") > -1) {
endpos = -1;
startpos = rest.indexOf("=");
singlefnuttpos = rest.indexOf("'", startpos);
doublefnuttpos = rest.indexOf('"', startpos);
spacepos = rest.indexOf(" ", startpos + 2);
if (spacepos > -1 && (spacepos < singlefnuttpos || singlefnuttpos == -1) && (spacepos < doublefnuttpos || doublefnuttpos == -1)) {
endpos = rest.indexOf(" ", startpos);
} else if (doublefnuttpos > -1 && (doublefnuttpos < singlefnuttpos || singlefnuttpos == -1) && (doublefnuttpos < spacepos || spacepos == -1)) {
endpos = rest.indexOf('"', rest.indexOf('"', startpos) + 1);
} else if (singlefnuttpos > -1 && (singlefnuttpos < doublefnuttpos || doublefnuttpos == -1) && (singlefnuttpos < spacepos || spacepos == -1)) {
endpos = rest.indexOf("'", rest.indexOf("'", startpos) + 1);
}
if (!endpos || endpos == -1 || endpos < startpos) {endpos = rest.length;}
done += rest.substring(0, startpos);
done += attributeValueMode(rest.substring(startpos, endpos + 1));
rest = rest.substr(endpos + 1);
}
return "<span style=color:" + attributecolor + ">" + done + rest + "</span>";
}
function attributeValueMode(txt) {
return "<span style=color:" + attributevaluecolor + ">" + txt + "</span>";
}
function commentMode(txt) {
return "<span style=color:" + commentcolor + ">" + txt + "</span>";
}
function cssMode(txt) {
var rest = txt, done = "", s, e, comment, i, midz, c, cc;
comment = new extract(rest, /\/\*/, "*/", commentMode, "W3CSSCOMMENTPOS");
rest = comment.rest;
while (rest.search("{") > -1) {
s = rest.search("{");
midz = rest.substr(s + 1);
cc = 1;
c = 0;
for (i = 0; i < midz.length; i++) {
if (midz.substr(i, 1) == "{") {cc++; c++}
if (midz.substr(i, 1) == "}") {cc--;}
if (cc == 0) {break;}
}
if (cc != 0) {c = 0;}
e = s;
for (i = 0; i <= c; i++) {
e = rest.indexOf("}", e + 1);
}
if (e == -1) {e = rest.length;}
done += rest.substring(0, s + 1);
done += cssPropertyMode(rest.substring(s + 1, e));
rest = rest.substr(e);
}
rest = done + rest;
rest = rest.replace(/{/g, "<span style=color:" + cssdelimitercolor + ">{</span>");
rest = rest.replace(/}/g, "<span style=color:" + cssdelimitercolor + ">}</span>");
for (i = 0; i < comment.arr.length; i++) {
rest = rest.replace("W3CSSCOMMENTPOS", comment.arr[i]);
}
return "<span style=color:" + cssselectorcolor + ">" + rest + "</span>";
}
function cssPropertyMode(txt) {
var rest = txt, done = "", s, e, n, loop;
if (rest.indexOf("{") > -1 ) { return cssMode(rest); }
while (rest.search(":") > -1) {
s = rest.search(":");
loop = true;
n = s;
while (loop == true) {
loop = false;
e = rest.indexOf(";", n);
if (rest.substring(e - 5, e + 1) == "&nbsp;") {
loop = true;
n = e + 1;
}
}
if (e == -1) {e = rest.length;}
done += rest.substring(0, s);
done += cssPropertyValueMode(rest.substring(s, e + 1));
rest = rest.substr(e + 1);
}
return "<span style=color:" + csspropertycolor + ">" + done + rest + "</span>";
}
function cssPropertyValueMode(txt) {
var rest = txt, done = "", s;
rest = "<span style=color:" + cssdelimitercolor + ">:</span>" + rest.substring(1);
while (rest.search(/!important/i) > -1) {
s = rest.search(/!important/i);
done += rest.substring(0, s);
done += cssImportantMode(rest.substring(s, s + 10));
rest = rest.substr(s + 10);
}
result = done + rest;
if (result.substr(result.length - 1, 1) == ";" && result.substr(result.length - 6, 6) != "&nbsp;" && result.substr(result.length - 4, 4) != "&lt;" && result.substr(result.length - 4, 4) != "&gt;" && result.substr(result.length - 5, 5) != "&amp;") {
result = result.substring(0, result.length - 1) + "<span style=color:" + cssdelimitercolor + ">;</span>";
}
return "<span style=color:" + csspropertyvaluecolor + ">" + result + "</span>";
}
function cssImportantMode(txt) {
return "<span style=color:" + cssimportantcolor + ";font-weight:bold;>" + txt + "</span>";
}
function jsMode(txt) {
var rest = txt, done = "", esc = [], i, cc, tt = "", sfnuttpos, dfnuttpos, compos, comlinepos, keywordpos, numpos, mypos, dotpos, y;
for (i = 0; i < rest.length; i++) {
cc = rest.substr(i, 1);
if (cc == "\\") {
esc.push(rest.substr(i, 2));
cc = "W3JSESCAPE";
i++;
}
tt += cc;
}
rest = tt;
y = 1;
while (y == 1) {
sfnuttpos = getPos(rest, "'", "'", jsStringMode);
dfnuttpos = getPos(rest, '"', '"', jsStringMode);
compos = getPos(rest, /\/\*/, "*/", commentMode);
comlinepos = getPos(rest, /\/\//, "<br>", commentMode);
numpos = getNumPos(rest, jsNumberMode);
keywordpos = getKeywordPos("js", rest, jsKeywordMode);
dotpos = getDotPos(rest, jsPropertyMode);
if (Math.max(numpos[0], sfnuttpos[0], dfnuttpos[0], compos[0], comlinepos[0], keywordpos[0], dotpos[0]) == -1) {break;}
mypos = getMinPos(numpos, sfnuttpos, dfnuttpos, compos, comlinepos, keywordpos, dotpos);
if (mypos[0] == -1) {break;}
if (mypos[0] > -1) {
done += rest.substring(0, mypos[0]);
done += mypos[2](rest.substring(mypos[0], mypos[1]));
rest = rest.substr(mypos[1]);
}
}
rest = done + rest;
for (i = 0; i < esc.length; i++) {
rest = rest.replace("W3JSESCAPE", esc[i]);
}
return "<span style=color:" + jscolor + ">" + rest + "</span>";
}
function jsStringMode(txt) {
return "<span style=color:" + jsstringcolor + ">" + txt + "</span>";
}
function jsKeywordMode(txt) {
return "<span style=color:" + jskeywordcolor + ">" + txt + "</span>";
}
function jsNumberMode(txt) {
return "<span style=color:" + jsnumbercolor + ">" + txt + "</span>";
}
function jsPropertyMode(txt) {
return "<span style=color:" + jspropertycolor + ">" + txt + "</span>";
}
function getDotPos(txt, func) {
var x, i, j, s, e, arr = [".","<", " ", ";", "(", "+", ")", "[", "]", ",", "&", ":", "{", "}", "/" ,"-", "*", "|", "%"];
s = txt.indexOf(".");
if (s > -1) {
x = txt.substr(s + 1);
for (j = 0; j < x.length; j++) {
cc = x[j];
for (i = 0; i < arr.length; i++) {
if (cc.indexOf(arr[i]) > -1) {
e = j;
return [s + 1, e + s + 1, func];
}
}
}
}
return [-1, -1, func];
}
function getMinPos() {
var i, arr = [];
for (i = 0; i < arguments.length; i++) {
if (arguments[i][0] > -1) {
if (arr.length == 0 || arguments[i][0] < arr[0]) {arr = arguments[i];}
}
}
if (arr.length == 0) {arr = arguments[i];}
return arr;
}
function getKeywordPos(typ, txt, func) {
var words, i, pos, rpos = -1, rpos2 = -1, patt;
if (typ == "js") {
words = ["abstract","arguments","boolean","break","byte","case","catch","char","class","const","continue","debugger","default","delete",
"do","double","else","enum","eval","export","extends","false","final","finally","float","for","function","goto","if","implements","import",
"in","instanceof","int","interface","let","long","NaN","native","new","null","package","private","protected","public","return","short","static",
"super","switch","synchronized","this","throw","throws","transient","true","try","typeof","var","void","volatile","while","with","yield"];
}
for (i = 0; i < words.length; i++) {
pos = txt.indexOf(words[i]);
if (pos > -1) {
patt = /\W/g;
if (txt.substr(pos + words[i].length,1).match(patt) && txt.substr(pos - 1,1).match(patt)) {
if (pos > -1 && (rpos == -1 || pos < rpos)) {
rpos = pos;
rpos2 = rpos + words[i].length;
}
}
}
}
return [rpos, rpos2, func];
}
function getPos(txt, start, end, func) {
var s, e;
s = txt.search(start);
e = txt.indexOf(end, s + (end.length));
if (e == -1) {e = txt.length;}
return [s, e + (end.length), func];
}
function getNumPos(txt, func) {
var arr = ["<br>", " ", ";", "(", "+", ")", "[", "]", ",", "&", ":", "{", "}", "/" ,"-", "*", "|", "%", "="], i, j, c, startpos = 0, endpos, word;
for (i = 0; i < txt.length; i++) {
for (j = 0; j < arr.length; j++) {
c = txt.substr(i, arr[j].length);
if (c == arr[j]) {
if (c == "-" && (txt.substr(i - 1, 1) == "e" || txt.substr(i - 1, 1) == "E")) {
continue;
}
endpos = i;
if (startpos < endpos) {
word = txt.substring(startpos, endpos);
if (!isNaN(word)) {return [startpos, endpos, func];}
}
i += arr[j].length;
startpos = i;
i -= 1;
break;
}
}
}
return [-1, -1, func];
}
}
</script>
</body>
</html>
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