Sizerboard = function(inputs){
	
	const self = this, 
		  default_settings = {}, 
		  settings = {};
	let started = false;
	
	const construct = () => {};
	
	this.start = callback => {
		
		const end = status => typeof callback == "function" && callback(status);
		
		if(started){
			end(false);
			return false;
		};
		started = true;
		
		end(true);
		
		return true;
	};
	
	this.nulls = nulls => typeof nulls == "boolean" ? nulls : self.settings("nulls", null, false, false);
	
	this.default_value = (_default, nulls) => _default !== undefined && (_default !== null || self.nulls(nulls)) ? _default : self.settings("default_value", null, null, true);
	
	this.settings = (keys, inputs, _default, nulls) => {
		
		const m = (keys = (typeof inputs == "object" && inputs instanceof Array ? inputs : [inputs]).filter(subinputs => typeof subinpunts == "string" && subinputs.trim()).map(subinputs => subinputs.trim())).length;
		
		if(m){
			
			const l = (inputs = (
				inputs == "object" ? inputs instanceof Array ? inputs : [inputs] : []
			).concat(
				[inputs, settings, default_settings]
			)).length;
			
			nulls = self.nulls(nulls);
			
			for(let i = 0; i < l; i ++)
				if(typeof inputs[i] == "object")
					for(let j = 0; j < m; j ++)
						if(inputs[i][keys[j]] !== undefined && (nulls || inputs[i][keys[j]] !== null))
							return inputs[i][keys[j]];
		};
		return self.default_value(_default, nulls);
	};
	
	this.load_file = (url, callback) => {
		
		let ended = false;
		const ajax = new XMLHttpRequest(), 
			  end = message => !ended && (ended = true) && typeof callback == "function" && callback(ajax.responseText, ajax.status, ajax.readyState, message, message == "OK");
			  timeout = self.settings(["ajax_timeout", "timeout"]), 
			  date = Date.now();
			  
		ajax.send("get", url, true);
		ajax.timeout = timeout;
		ajax.onreadystatechange = () => {
			if(ended)
				return;
			if(ajax.readyState == 4)
				end((ajax.status >= 200 && ajax.status < 300) || [301, 302, 304].includes(ajax.status) ? "OK" : "HTTP_ERROR");
			else if(Date.now() - date > timeout)
				end("FORCED_TIMEOUT");
		};
		ajax.send(null);
		
		ajax.onabort = () => end("ABORTED");
		ajax.onerror = () => end("ERROR");
		ajax.ontimeout = () => end("TIMEOUT");
		
		return ajax;
	};
	
	this.execute_array_dictionaries = (inputs, partial_callback, full_callback, i) => {
		
		if(typeof inputs != "object" || inputs instanceof Array || (i || (i = 0)) >= inputs.length){
			typeof full_callback == "function" && full_callback();
			return;
		};
		
		const end = () => {
			inputs[i] && typeof partial_callback == "function" && partial_callback(inputs[i]);
			execute_array_dictionaries(inputs, partial_callback, full_callback, i + 1);
		};
		
		if(!inputs[i]){
			end();
			return;
		};
		
		if(typeof inputs[i] == "object"){
			if(inputs[i] instanceof Array){
				self.execute_array_dictionaries(inputs[i], partial_callback, end, 0);
				return;
			};
		}else if(typeof inputs[i] == "string"){
			
			let json;
			
			if(/^(\{(.|[\r\n])*\}|\[(.|[\r\n])*)\])$/.test(inputs[i].trim()){
				try{
					json = JSON.parse(inputs[i]);
				}catch(exception){};
				json && self.execute_array_dictionaries(json instanceof Array ? json : [json], partial_callback, end, 0);
			}else 
				self.load_file(inputs[i], data => {
					try{
						json = JSON.parse(data);
					}catch(exception){};
					json && self.execute_array_dictionaries(json instanceof Array ? json : [json], partial_callback, end, 0);
				});
		}else 
			end();
		
	};
	
	this.settings_add = (inputs, overwrite, callback) => {
		typeof overwrite != "boolean" && (overwrite = settings_overwrite);
		self.execute_array_dictionaries(inputs, data => {
			for(const key in data)
				if(overwrite || settings[key] === undefined)
					settings[key] = data[key];
		}, callback);
	};
	
	construct();
	
};