Terminal-style table generator

Tabula.js

  
  function Tabula(init) { 
  	this.fields = init.fields;
  	this.values = init.values;
  	
  	function maxFieldLength(values, fields) {
  		return values.map(function(value, index) {
  			return Math.max(value.length, fields[index % fields.length].length);
  		}).map(function(value, index, full) {
  			return Math.max(value, full[index + full.length/2]);
  		}).filter(function(v) { return !isNaN(v) });
  	}
  	
  	function padFields(fields, values, padding) {
  		return fields.map(function(field, index) {
  			var maxlengths = maxFieldLength(values, fields);
  			while (field.length < maxlengths[index]) {
  				field = field + padding;
  			}
  			return field;
  		});
  	}
  	
  	function padValues(values, fields, padding) {
  		return values.map(function(value, index) {
  			while (value.length < fields[index % fields.length].length) {
  				value = value + padding;
  			}
  			return value;
  		});
  	}
  	
  	this.fields = padFields(this.fields, this.values, this.padding);
  	this.values = padValues(this.values, this.fields, this.padding);
  	
  	
  	this.representation = [];
  }
  
  	Tabula.prototype.padding = " ";
  	
  	Tabula.prototype.ends = {
  		start: '|' + Tabula.prototype.padding,
  		end: Tabula.prototype.padding + '|'
  	}
  	
  	Tabula.prototype.sep = Tabula.prototype.padding + Tabula.prototype.ends.start;
  	
  	Tabula.prototype.length = function() {
  		return this.fields.map(function(field) {
  			return field.length;
  		}).reduce(function(a, b) {
  			return a + b;
  		}, 0);
  	};
  
  	Tabula.prototype.hr = function() {
  		return '+' + '-'.repeat(this.length() + this.sep.repeat(this.fields.length).length-1) + '+';
  	};
  	
  	Tabula.prototype.header = function() {
  		this.representation.push(this.hr(), this.ends.start + this.fields.join(this.sep) + this.ends.end);
  	}
  	
  	function arraySplit(array, delim) {
  		var ret = [];
  		array.forEach(function(value, index) {
  			if (index % delim === 0)
  				ret.push(array.slice(index, index+delim));
  		});
  		return ret;
  	}
  	
  	Tabula.prototype.cells = function() {
  		var values = arraySplit(this.values, this.fields.length);
  		values.forEach(function(value) {
  			var row = this.ends.start + value.join(this.sep) + this.ends.end;
  			this.representation.push(this.hr(), row);
  		}, this);
  	}
  	
  	Tabula.prototype.footer = function() {
  		this.representation.push(this.hr());
  	}
  	
  	Tabula.prototype.render = function() {
  		this.header();
  		this.cells();
  		this.footer();
  		return this.representation.join("\n");
  	}
  
  /* tests */
  
  var table = new Tabula({
  	fields: ['name', 'age', 'color'],
  	values: ['samantha', '23', 'rouge', 'toby', '18', 'silver']
  });
  console.log(table.render());
  
  var table2 = new Tabula({
  	fields: ['type', 'smell'],
  	values: ['red', 'apple', 'magenta', 'blackcurrant']
  });
  console.log(table2.render());