var exports = (function() {

	var NoteQuota = function(cb) {
		this.cb = cb;
		this.setParams();
		this.resetPoints();
	};

	NoteQuota.PARAMS_LOBBY = {allowance: 200, max: 600};
	NoteQuota.PARAMS_NORMAL = {allowance: 400, max: 1200};
	NoteQuota.PARAMS_RIDICULOUS = {allowance: 600, max: 1800};
	NoteQuota.PARAMS_OFFLINE = {allowance: 8000, max: 24000, maxHistLen: 3};

	NoteQuota.prototype.getParams = function() {
		return {
			m: "nq",
			allowance: this.allowance,
			max: this.max,
			maxHistLen: this.maxHistLen
		};
	};

	NoteQuota.prototype.setParams = function(params) {
		params = params || NoteQuota.PARAMS_OFFLINE;
		var allowance = params.allowance || this.allowance || NoteQuota.PARAMS_OFFLINE.allowance;
		var max = params.max || this.max || NoteQuota.PARAMS_OFFLINE.max;
		var maxHistLen = params.maxHistLen || this.maxHistLen || NoteQuota.PARAMS_OFFLINE.maxHistLen;
		if(allowance !== this.allowance || max !== this.max || maxHistLen !== this.maxHistLen) {
			this.allowance = allowance;
			this.max = max;
			this.maxHistLen = maxHistLen;
			this.resetPoints();
			return true;
		}
		return false;
	};

	NoteQuota.prototype.resetPoints = function() {
		this.points = this.max;
		this.history = [];
		for(var i = 0; i < this.maxHistLen; i++)
			this.history.unshift(this.points);
		if(this.cb) this.cb(this.points);
	};

	NoteQuota.prototype.tick = function() {
		// keep a brief history
		this.history.unshift(this.points);
		this.history.length = this.maxHistLen;
		// hook a brother up with some more quota
		if(this.points < this.max) {
			this.points += this.allowance;
			if(this.points > this.max) this.points = this.max;
			// fire callback
			if(this.cb) this.cb(this.points);
		}
	};

	NoteQuota.prototype.spend = function(needed) {
		// check whether aggressive limitation is needed
		var sum = 0;
		for(var i in this.history) {
			sum += this.history[i];
		}
		if(sum <= 0) needed *= this.allowance;
		// can they afford it?  spend
		if(this.points < needed) {
			return false;
		} else {
			this.points -= needed;
			if(this.cb) this.cb(this.points); // fire callback
			return true;
		}
	};

	return NoteQuota;

})();

if(typeof module !== "undefined") {
	module.exports = exports;
} else {
	this.NoteQuota = exports;
}