elbus 0.2.21

'use strict'

function tqdm(){
    
	/**
	 * renders progress to a string
	 * @private 
	 * @param {Number} n - iterations completed
	 * @param {Number} total - total iterations to do
	 * @param {Number} elapsed - time taken so fa in ms
	 * @return {Object} ret - the combined object
	 */
	function _render(n, total, elapsed) {

		var cent = n/total*100;
		var est = (100 - (cent+0.000001))/(cent+0.0000001) * elapsed;
		var ips = n / ((elapsed+0.000001)/1000);
		cent = Math.floor(cent);

		var out = "|";
		for(let i = 0; i < 10; i++) {
			if(i >= Math.round(cent/10)) {
				out += "-";
			} else {
				out += "#";
			}
		}

		out += "| " + n + "/" + total + " " + cent + "% [";

		out += "elapsed: " + _formatter(elapsed) + " ";
		out += "left: " + _formatter(est) + ", ";
		out += ips.toFixed(2) + " iters/s]\n";

		return out;
	}


	/**
	 * Formats a time in ms to HH:MM:SS, or MM:SS if the time is less than an hour
	 * @private 
	 * @param {Number} msec
	 * @return {string} out
	 */
	function _formatter(msec) {

		var out = "";
		var sec = Math.floor(msec / 1000);
		var min = Math.floor(sec / 60);
		var hour = Math.floor(min / 60);
		sec = sec - min * 60;
		min = min - hour * 60;
		if(hour > 0) {
			if(hour < 10) {
				out = "0"
			}
			out = out + hour.toString() + ":";
		}
		if(min < 10) {
			out = out + "0";
		}
		out = out + min.toString() +":";
		if(sec < 10) {
			out = out + "0";
		}
		out = out + sec.toString();

		return out;
	}
		
	/**
	 * Adds a timed progress bar to iterables
	 * @param {Iterable} iter
	 * @param {Object} par - The optional parameters
	 * @param {string} par.desc - A desciption string to add before the progress bar
	 * @param {Number} par.total - The number of iterations to complete, needed for infinite iterables
	 * @param {Number} par.minIter - The minimum number of iterations between progress bar updates
	 * @param {Number} par.minInterval - The minimum amount of time between progress bar updates
	 * @param {Boolean} par.logging - whether to output as a log, or update the same line
	 */
	return function* (iter, par) {

		var def = {
			desc:'',
			minIter: 1,
			minInterval: 500,
			logging: false
		};

		var params = {}
		if(typeof def === 'object') {
			for(let i in def) {
				params[i] = def[i];
			}
		}
		if(typeof par === 'object') {		
			for(let i in par) {
				params[i] = par[i];
			}
		}
		var start = Date.now();
		var now = start;
		var n = 0; 
		var lastn = 0;
		var elapsed;
		var lastElapsed  = 0;;

		if(!("total" in params)) {
			for (let i of iter) {
				n++;
			}
			params["total"] = n;
			n = 0;
		}

		console.log(params.desc);

		// put an initial bar out
		process.stdout.write(_render(0,params.total,0));

		// iterations
		for (let i of iter) {
			yield i;
			n++;
			elapsed = Date.now() - start;
			if(n - lastn >= params.minIter && elapsed - lastElapsed >= params.minInterval) {
				if(params.logging) {
					process.stdout.write("\u001b[1F\u001b[2K");
				}
				
				lastn = n;
				lastElapsed = elapsed;
				process.stdout.write(_render(n, params.total, elapsed));
			}
			if(n > params.total) {
				break;
			}
		}
	}
}

module.exports = tqdm();