Function.prototype.bind = function(object) {
	var method = this;
	return function() {
		return method.apply(object, arguments);
	}
};

Number.prototype.toAutoFixed = function () {
	var v = Math.abs(this);
	if (v < 0.0001) {
		v = v.toFixed(10).substr(2);
		for (var i = 0, j = v.length; i < j && i < 8; i++) {
			if (0 != v.charAt(i)) {
				return this.toFixed(i + 1);
			}
		}
		return 0;
	}
	return this.toFixed(4);
};

function financeUaCurrencyConverter (el) {
	this.el = el;
	this.fromCurrencyRate = 0;
	this.toCurrencyRate = 0;
	this.crossRate = 0;
	this.sourceData = null;
}

financeUaCurrencyConverter.prototype = {
	setSourceData : function (value) {
		if (null == value) {
			this.sourceData = null;
			return false;
		} else {
			this.sourceData = eval('(' + value + ')');
			return true;
		}
	},
	calculate : function () {
		this.fromCurrencyRate = 0;
		this.toCurrencyRate = 0;
		this.crossRate = 0;

		var k = this.sourceData.key;

		this.fromCurrencyRate = this.toFloat(this.sourceData.data[this.el.fromCurrency.value][k.official_rate])
			/ this.toInt(this.sourceData.data[this.el.fromCurrency.value][k.official_amount]);

		this.toCurrencyRate = this.toFloat(this.sourceData.data[this.el.toCurrency.value][k.official_rate])
			/ this.toInt(this.sourceData.data[this.el.toCurrency.value][k.official_amount]);

		if (0 != this.fromCurrencyRate) {
			this.crossRate = this.toFloat(this.el.fromCurrencyAmount.value) * this.fromCurrencyRate / this.toCurrencyRate;
			var percent = this.toFloat(this.el.percentValue.value) * this.crossRate / 100;
			this.crossRate = ('+' == this.el.percentSign.value)
				? this.crossRate + percent
				: this.crossRate - percent;
		}
	},
	toInt : function (value) {
		var result = parseInt(value);
		return (isNaN(result))
			? 0
			: result;
	},
	toFloat : function (value) {
		var result = parseFloat(value);
		return (isNaN(result))
			? 0
			: result;
	}
};

function gadgetFinanceUaCurrencyConverter (moduleId, isIE) {

	this.el = {
		'container' : _gel('container' + moduleId),
		'source' : _gel('source' + moduleId),
		'fromCurrencyAmount' : _gel('fromCurrencyAmount' + moduleId),
		'fromCurrency' : _gel('fromCurrency' + moduleId),
		'toCurrency' : _gel('toCurrency' + moduleId),
		'percentSign' : _gel('percentSign' + moduleId),
		'percentValue' : _gel('percentValue' + moduleId),
		'logPanel' : _gel('logPanel' + moduleId),
		'infoPanel' : _gel('infoPanel' + moduleId),
		'resultPanel' : _gel('resultPanel' + moduleId)
	};

	this.userPrefs = {
		'source' : { 'type' : 'select' },
		'fromCurrencyAmount' : { 'type' : 'text' },
		'fromCurrency' : { 'type' : 'select' },
		'toCurrency' : { 'type' : 'select' },
		'percentSign' : { 'type' : 'select' },
		'percentValue' : { 'type' : 'text' }
	};

	this.savePrefsDelayTimerId = null;
	this.prefs = new _IG_Prefs(moduleId);
	this.loadPrefs();

	this.preferredCurrency = {};
	this.loadPreferredCurrency();

	this.shortCurrencyNames = false;
	this.calcCount = 0;
	this.sourceUrl = 'http://content.finance.ua/' + this.prefs.getMsg('language') + '/export/google-gadgets/currency-official/~';

	this.converter = new financeUaCurrencyConverter(this.el);
	this.event('source');

	window.onresize = function () { this.onResize(); }.bind(this);
	this.onResize();
}

gadgetFinanceUaCurrencyConverter.prototype = {
	loadSource : function (sourceId) {
		this.showMessage('loading');
		_IG_FetchContent(this.sourceUrl + '/' + sourceId, function(response) {
			if (this.converter.setSourceData(response)) {
				this.showMessage('loadingSuccessful');
				this.reloadCurrencySelector('fromCurrency');
				this.reloadCurrencySelector('toCurrency');
				this.event('toCurrency');
			} else {
				this.showMessage('loadingError', true);
			}
		}.bind(this), { refreshInterval: 3600 });
	},
	loadPreferredCurrency : function() {
		var r = /^[A-Za-z]{3}$/;
		var x = this.prefs.getArray('preferredCurrency');
		for (var i in x) {
			if (r.test(x[i])) {
				this.preferredCurrency[x[i].toUpperCase()] = true;
			}
		}
	},
	loadPrefs : function () {
		for (var p in this.userPrefs) {
			value = this.prefs.getString(p);
			switch (this.userPrefs[p].type) {
				case 'text':
					this.el[p].value = value;
					break;

				case 'select':
					for (var i = 0, j = this.el[p].options.length; i < j; i++) {
						var o = this.el[p].options[i];
						if (o.value == value) {
							o.selected = true;
							break;
						}
					}
					break;
			}
		}
	},
	savePrefs : function () {
		this.savePrefsDelayTimerStop();
		this.savePrefsDelayTimerId = setTimeout(function() {
			for (var p in this.userPrefs) {
				this.prefs.set(p, this.el[p].value);
			}
			this.savePrefsDelayTimerId = null;
		}.bind(this), 5000);
	},
	savePrefsDelayTimerStop : function () {
		if (this.savePrefsDelayTimerId) {
			clearTimeout(this.savePrefsDelayTimerId);
		}
	},
	event : function (el, event) {
		if ('object' != typeof el) {
			el = this.el[el];
		}
		switch(el.id) {
			case this.el.source.id:
				this.calcCount = 0;
				this.loadSource(el.value);
				break;

			default:
				if (null == this.converter.sourceData) {
					this.showMessage('loadingError', true);
					break;
				}

				if (!this.checkInput(this.el.fromCurrencyAmount)
					|| !this.checkInput(this.el.percentValue)) {

					this.savePrefsDelayTimerStop();
					break;
				}

				if (event) {
					var k = event.keyCode;
					if (!((k > 47 && k < 58) || k == 8 || k == 46 || k == 190)) { // num, BS, DEL, .
						break;
					}
				}
				this.converter.calculate();
				this.updateInfoPanel(this.converter.fromCurrencyRate, this.converter.toCurrencyRate);
				this.updateResultPanel(this.converter.crossRate);
				this.savePrefs();
				this.calcCount++;

				switch (this.calcCount) {
					case 1:
						_IG_AdjustIFrameHeight();
						break;
					case 2:
						this.showMessage();
						break;
				}
				break;
		}
	},
	reloadCurrencySelector : function (elementName) {
		var el = this.el[elementName];
		var selected  = (0 == el.options.length)
			? this.prefs.getString(elementName)
			: el.value;

		if (!this.converter.sourceData.data[selected]) {
			selected = ('fromCurrency' == elementName)
			    ? 'USD'
			    : this.converter.sourceData.source_currency;
		}

		el.options.length = 0;

		var k;
		for (k in this.preferredCurrency) {
			if (this.converter.sourceData.data[k]) {
				el.options.add(this.createOption(k, this.converter.sourceData.data[k][this.converter.sourceData.key.currency_title], selected));
			}
		}

		if (el.options.length) {
			el.options.add(this.createOption(null));
		}

		for (k in this.converter.sourceData.data) {
			if ('   ' == k || this.preferredCurrency[k]) {
				continue;
			}
			el.options.add(this.createOption(k, this.converter.sourceData.data[k][this.converter.sourceData.key.currency_title], selected));
		}
	},
	createOption: function(k, v, s) {
		var o = document.createElement('OPTION');
		if (k) {
			o.text = this.shortCurrencyNames ? k : '[' + k + '] ' + v;
			o.value = k;
			if (k == s) {
				o.selected = true;
			}
		} else {
			o.text = '\u2014';
			o.disabled = true;
		}
		return o;
	},
	checkInput : function (el) {
		var r = /^\d+(\.\d{0,2})?$/;
		var d = /[,-]/;
		if (d.test(el.value)) {
			el.value = el.value.replace(d, '.');
		}
		if (!r.test(el.value)) {
			el.style.backgroundColor = '#ffcccc';
			return false;
		} else {
			el.style.backgroundColor = '#ffffff';
			return true;
		}
	},
	showMessage : function (messageId, clean) {
		this.el.logPanel.innerHTML = messageId ? this.prefs.getMsg(messageId) : '&nbsp;';
		if (clean) {
			this.el.resultPanel.innerHTML = '&nbsp;';
			this.el.infoPanel.innerHTML = '&nbsp;';
		}
	},
	updateResultPanel : function (crossRate) {
		var html = this.prefs.getMsg('lblCalculate') + ' ' + this.converter.sourceData.date + ':<br><b>'
			+ parseFloat(this.el.fromCurrencyAmount.value) + ' ' + this.el.fromCurrency.value;

		if (this.el.percentValue.value > 0) {
			html += ' ' + this.el.percentSign.value + ' ' + parseFloat(this.el.percentValue.value) + '%';
		}

		html += ' = ' + crossRate.toAutoFixed() + ' ' + this.el.toCurrency.value + '</b>';

		this.el.resultPanel.innerHTML = html;
	},
	updateInfoPanel : function (fromCurrencyRate, toCurrencyRate) {
		var html = this.prefs.getMsg('lblAdditional') + ':<br><b>';
		if (this.el.fromCurrency.value != this.converter.sourceData.source_currency) {
		    html += '1 ' + this.el.fromCurrency.value + ' = '
			+ fromCurrencyRate.toAutoFixed() + ' ' + this.converter.sourceData.source_currency;
		}

		if (this.el.fromCurrency.value != this.converter.sourceData.source_currency
			&& this.el.toCurrency.value != this.converter.sourceData.source_currency) {
			html += ', ';
		}

		if (this.el.toCurrency.value != this.converter.sourceData.source_currency) {
		    html += '1 ' + this.el.toCurrency.value + ' = '
			+ toCurrencyRate.toAutoFixed() + ' ' + this.converter.sourceData.source_currency;
		}

		html += '</b>';

		this.el.infoPanel.innerHTML = html;
	},
	onResize : function () {
		var lastState = this.shortCurrencyNames;
		this.shortCurrencyNames = this.el.fromCurrency.offsetWidth < 100;

		if (lastState != this.shortCurrencyNames) {
			this.reloadCurrencySelector('fromCurrency');
			this.reloadCurrencySelector('toCurrency');
		}

		this.el.fromCurrency.style.width = this.el.container.clientWidth > 280 ? '190px' : '100%';
		this.el.toCurrency.style.width = this.el.container.clientWidth > 280 ? '245px' : '100%';
	}
};