Utility(Data):DnD View Types

(() =>{

var getDataType = (v) => {
  var tags = [];
  //is anything there?
  var isTruthy = v ? true : false;
  //check the data type of root value
  var dataType = typeof v;
  var isNumber = (s) => !isNaN(+s);
  var isDate = (s) => !isNaN(Date.parse(s));
  var processString = (s) => {
    s = s.replace(/[$,%]/gim,"").trim();
    s == "true" || s == "false" ? tags.push("boolean") : //if true or false, tag bool
      isNumber(s) ? tags.push("number") : //else if is convertable to number, tag num
      isDate(s) ? tags.push("date") : //else if is convertable to date, tag date
    tags.push(`string_${s.length}`); //else tag string
  }
  switch(dataType){
    case "number":
      tags.push("number");
      break;
    case "boolean":
      console.log("BOOL",{v})
      tags.push("boolean")
      break;
    case "string":
      v.length ? processString(v) : tags.push("string_0")
      break;
    case "object":
      Array.isArray(v) ?
        v.length ? tags.push(v.map(d => getDataType(d))) : tags.push([]) :
        v && Object.values(v).length ? tags.push(Object.entries(v).reduce((obj,d) => {
            obj[d[0]] = getDataType(d[1]);
            return obj;
          },{})) : tags.push({});
      break;
  }
  return tags.length == 1 ? tags[0] : tags;
}

var options = {
		scripts: ["https://d3js.org/d3.v5.min.js"]
	}
const fileToString = (inputFile) => {
	const fr = new FileReader();
	return new Promise((resolve, reject) => {
		fr.onerror = () => {fr.abort(); reject({error:"file reader error"})}
		fr.onload = () => resolve(fr.result); 
		fr.readAsText(inputFile);
})}
const dropHandler = async (e) => {
	e.preventDefault(); //disable default drop behavior
  for await (let file of e.dataTransfer.files) { //loop through dropped files
		let r = {format:file.name.slice(file.name.lastIndexOf(".")+1)}
		const str = await fileToString(file); //convert dropped file to string
		var parse = () => {
			var stringParser = () => {
				var parseStr = (delimiter) => str.split(delimiter);
				var testStr = (delimiter) => str.indexOf(delimiter) > -1
				var t = {hasLines:testStr("\n"),hasComma:testStr(","),hasTab:testStr("\t")};
				return t.hasLines ? parseStr("\n") : t.hasTab ? parseStr("\t") : t.hasComma ? parseStr(",") : [];
			}
			return r.format == "json" ? JSON.parse(str) :
			 r.format == "txt" ? stringParser() :
			 r.format == "csv" ? d3.csvParse(str) : []
		};
		r.name = file.name.replace("."+r.format,""),
		r.data = parse();
		console.log({report:r}); 
		
		var report = getDataType(r.data);
		var reportString = JSON.stringify(report,null,"|");
		var depthReport = reportString.split("\n").map(s => s.match(/\|/gim,"") ? s.match(/\|/gim,"").length : 0);
		console.log({report,depthReport})

}
 }
window.ondragover = (e) => e.preventDefault();
window.ondrop = (e) => dropHandler(e); 
const loadScripts = (scripts) => {
	console.log(`Loading External Scripts`);
	var scriptCountdown = scripts.length;
	var loadScript = (url) => {
		var scriptsLoaded = () => {
			scriptCountdown == 0 ? console.log("External scripts loaded. Ready to parse!") : null;
			return true;
		}
		var imported = document.createElement('script');
				imported.src = url;
				imported.addEventListener("load", () => {scriptCountdown--; scriptsLoaded();});
				document.head.appendChild(imported);
	}
	scripts.forEach(loadScript)
}
loadScripts(options.scripts);
})();