var types = []
var units = []
var allFromUnits = []
var toUnits = []

var ct = [
	'distance,angstrom,1e13',
	'distance,centimeter,100000',
	'distance,feet,3280.8399',
	'distance,foot,3280.8399',
	'distance,inch,39370.0787',
	'distance,kilometer,1',
	'distance,meter,1000',
	'distance,metre,1000',
	'distance,micron,1e10',
	'distance,mile,0.621371192',
	'distance,millimeter,1e6',
	'distance,nanometer,1e12',
	'distance,yard,1093.6133',

	'weight,grain,15432.3583529',
	'weight,gram,1000',
	'weight,kilogram (kg),1',
	'weight,microgram,1000000000',
	'weight,milligram,1000000',
	'weight,ounce,35.2739619',
	'weight,pound,2.2046226',
	'weight,lb,2.2046226',
	'weight,ton,0.001',
	'weight,tonne,0.001',
	'weight,stone,0.157473044',

	'area,acre,0.0002471',
	'area,dunam,0.001',
	'area,hectare,0.0001',
	'area,square centimeter,10000',
	'area,square foot,10.7639104',
	'area,square furlong,0.0000247',
	'area,square inch,1550.0031',
	'area,square kilometer (km),0.000001',
	'area,square meter,1',
	'area,square mile,3.86102159e-7',
	'area,square yard,1.19599',

	'temperature,degree celcius,1',
	'temperature,farenheit,:(v-32)*5/9:v*9/5+32',
	'temperature,kelvin,:v-273.15:v+273.15',

	'speed,centimeter/second,100',
	'speed,foot/second,3.2808399',
	'speed,inch/second,39.3700787',
	'speed,kilometer/hour,3.6',
	'speed,kilometer/second,0.001',
	'speed,knot,1.9438445',
	'speed,meter/second,1',
	'speed,mile/hour (mph),2.2369363',
	'speed,mile/second,0.0006214',
	'speed,millimeter/second,1000',
	'speed,speed of light,3.3356409519815204e-9',
	'speed,speed of sound/mach,0.0029387',

	'volume,barrel (oil),0.0062898',
	'volume,bushel (UK),0.0274962',
	'volume,bushel (US),0.0283776',
	'volume,cubic centimeter (cc),1000',
	'volume,milliliter (ml),1000',
	'volume,cubic foot,0.035314666',
	'volume,cubic inch,61.023744',
	'volume,cubic meter,0.001',
	'volume,cubic millimeter,1000000',
	'volume,cubic yard,0.00130795',
	'volume,fluid ounce (UK),35.19507972',
	'volume,fluid ounce (US),33.8140227',
	'volume,gallon (UK),0.2199692',
	'volume,gallon (US),0.2641721',
	'volume,liter,1',
	'volume,litre,1',
	'volume,pint (UK),1.759754',
	'volume,pint (US),2.1133764',
	'volume,quart (UK),0.879877',
	'volume,quart (US),1.0566882',
	'volume,cup,4.22244',

	'' // Last
]

if (currencyTab)
	ct = ct.concat(currencyTab)

for (var i in ct)
{
	var s = ct[i]
	if (s != '')
	{
		var st = s.substring(0, s.indexOf(','))
		var sr = s.substring(s.indexOf(',')+1)
		var su = sr.substring(0, sr.indexOf(','))
		var sv = sr.substring(sr.indexOf(',')+1)
		var at = types[st]
		if (!at)
		{
			at = []
			types[st] = at
		}
		units[su] = at[at.length] = { category: st, unit:su, value:sv }
		allFromUnits[allFromUnits.length] = su
	}
}

function setCategory(cat)
{
	tabfocus('all', cat=='all')
	for (var category in types)
		tabfocus(category, category==cat)

	var fromOptions
	if (cat == 'all')
		fromOptions = allFromUnits
	else
	{
		fromOptions = new Array()
		var category = types[cat]
		if (category)
		{
			for (var i in category)
			{
				fromOptions[fromOptions.length]=category[i].unit
			}
		}
	}
	acFrom.setOptions(fromOptions)

	document.getElementById('fromUnits').value=''
	document.getElementById('toUnits').value=''

}
function tabfocus(name, on)
{
	var t = document.getElementById('cat_'+name)
	if (t)
		t.className = on ? 'catb_active': 'catb';
}

function fromset()
{
	var from = document.getElementById('fromUnits').value

	var toOptions = []

	var u = units[from]
	if (u)
	{
		var category = types[u.category]
		if (category)
		{
			for (var i in category)
			{
				toOptions[toOptions.length]=category[i].unit
			}
		}
		var to = document.getElementById('toUnits').value
		var tu = units[to]
		if (tu && u.category != tu.category)
			document.getElementById('toUnits').value = ''
	}


	acTo.setOptions(toOptions)
	compute()
}

function compute()
{
	var from = document.getElementById('fromUnits').value
	var to = document.getElementById('toUnits').value
	var samount = document.getElementById('amount').value
	if (samount=='')
		samount='1'
	var amount
	if (samount.indexOf('.') < 0)
		amount = parseInt(samount, 10)
	else
		amount = parseFloat(samount)

	if (isNaN(amount))
		amount=1

	var fu = units[from]
	var tu = units[to]
	var res = ""
	if (fu && tu && fu.category == tu.category)
	{
		var v
		if (fu.value.charAt(0) != ':' && tu.value.charAt(0) != ':')
		{
			v = amount * parseFloat(tu.value) / parseFloat(fu.value)
		}
		else
		{
			var v = amount
			if (fu.value.charAt(0) != ':')
				v = v  / parseFloat(fu.value)
			else
			{
				var f = fu.value.substring(1)
				f = f.substring(0, f.indexOf(':'))
				v = eval(f)
			}

			if (tu.value.charAt(0) != ':')
				v = v  * parseFloat(tu.value)
			else
			{
				var f = tu.value.substring(1)
				f = f.substring(f.indexOf(':')+1)
				v = eval(f)
			}
		}
		if (fu.category == 'currency')
			v = Math.round(v*10000) / 10000
		v = fixRoundingError(v)
		res = "<table border='1' cellpadding='2' cellspacing='0'><tr><td class='result'>"+amount+" "+fu.unit+" = "+v+" "+tu.unit+"</td></tr></table>"
		logAdd(amount, fu, tu, v)
	}
	document.getElementById('result').innerHTML = res
}
function amountFocus()
{
	document.getElementById('amount').focus()
}
function fixRoundingError(value)
{
	var sv = ""+value
	if (sv.indexOf('.') < 0)
		return value
	// TODO Handle "e" notation, leave only 12 digits after point
	var s = sv.substring(sv.indexOf('.'))
	var l = s.length
	if (l < 5)
		return value
	var i9 = s.indexOf('99')
	var i0 = s.indexOf('00')
	if (i9 >= 0)
	{
		while (s.charAt(i9-1) == '9')
			i9--
		s = s.substring(0,i9+1)
		var d = '.000000000000000000000000000000000'.substring(0,s.length-1)+'1'
		var w = sv.substring(0, sv.indexOf('.'))
		if (w == '')
			w = '0'
		var op = '+'
		if (value < 0)
			op = '-'
		value = eval(w+op+'('+s+'+'+d+')')
	}
	else
	if (i0 >= 0)
	{
		var w = sv.substring(0, sv.indexOf('.'))
		value = eval(w+'+'+s.substring(0, i0)+'0')
	}
	return value
}



//
// Log (history) functions
//
var log = new Array()
function logAdd(amount, fromu, tou, value)
{
	if (log.length == 0 || log[log.length-1].amount != amount || log[log.length-1].fromUnit.unit != fromu.unit || log[log.length-1].toUnit.unit != tou.unit)
	{
		if (fromu.unit != tou.unit)
		{
			var entry = new Object()
			entry.amount = amount
			entry.fromUnit = fromu
			entry.toUnit = tou
			entry.value = value
			log[log.length] = entry
			logShow()
		}
	}
}
function logShow()
{
	var str = ""
	var opts = ""
	if (log.length > 0)
	{
		str += "<span class='logtitle'>History</span><br />"
		opts += "<a href='javascript:logRemove()'>Remove checked lines</a>&nbsp&nbsp;"
		opts += "<a href='javascript:logCheckAll()'>Check all</a>&nbsp;&nbsp;"
		opts += "<a href='javascript:logClear()'>Clear history</a>&nbsp;&nbsp;"
		//opts += "<a href='javascript:copyLogToClipoard()' title='Copy all history into the clipboard in a spreadsheet format'>Copy all history</a>&nbsp;&nbsp;"
		opts += "<br /><br />"
		str += opts

		str += "<table border='0' cellpadding='2' cellspacing='1' bgcolor='#c0c0c0'>"

		str += "<tr class='loghdr'><td>&nbsp;</td><td>Conversion</td></tr>"
		for (var i=log.length-1; i>=0; i--)
		{
			var entry = log[i]
			if (entry != null)
			{
				str += "<tr bgcolor='#ffffff'>"
				str += "<td><input type='checkbox' id='log"+i+"' /></td>"
				str += "<td><a class='logval' title='Set units' href='javascript:logSet(&quot;"+entry.fromUnit.category+"&quot;,&quot;"+entry.fromUnit.unit+"&quot;,&quot;"+entry.toUnit.unit+"&quot;)'>"+entry.amount+" "+entry.fromUnit.unit+" = "+entry.value+" "+entry.toUnit.unit+"</a></td>"
				str += "</tr>"
			}
		}
		str += "</table>"
		str += opts
	}
	document.getElementById('log').innerHTML = str

	if (prefs.saveConvertHistory)
		saveConvertHistory();
}

function logSet(category, fromUnit, toUnit)
{
	setCategory(category)
	document.getElementById('fromUnits').value = fromUnit
	document.getElementById('toUnits').value = toUnit
}
function logClear()
{
	log = new Array()
	logShow()
}
function logRemove()
{
	var newLog = new Array()
	for (var i=0; i<log.length; i++)
	{
		var chkbox = document.getElementById('log'+i)
		if (chkbox && !chkbox.checked)
			newLog[newLog.length] = log[i]
	}
	log = newLog
	logShow()
}
function logCheckAll()
{
	for (var i=0; i<log.length; i++)
	{
		var chkbox = document.getElementById('log'+i)
		if (chkbox)
			chkbox.checked = true
	}
}

// History management in cookie
var convertHistoryCookieName = "convertHistory"
function saveConvertHistory()
{
	var value = "";
	var passedMaxSize = false

	for (var i=log.length-1; i >=0 && !passedMaxSize;i--)
	{
		var entry = log[i]
		if (entry != null)
		{
			var newValue= "//"+entry.amount+":"+entry.fromUnit.unit+":"+entry.toUnit.unit+":"+entry.value
			if (value.length+newValue.length<4096)
				value=newValue+value
			else
				passedMaxSize=true
		}
	}

	createCookie(convertHistoryCookieName, value, 365*10)
}
function readConvertHistory()
{
	if (prefs.saveConvertHistory == false)
		eraseCookie(convertHistoryCookieName);
	else
	{
		var value = readCookie(convertHistoryCookieName)
		log = new Array()

		while (value != null && value.indexOf("//")>=0) {
			var nextExpIndex = value.indexOf("//", 2)
			if (nextExpIndex != -1) {
				var conversion = value.substring(2, nextExpIndex)
				value = value.substring(nextExpIndex)
			} else {
				var conversion = value.substring(2)
				value = ""
			}

			var amount = conversion.substring(0,conversion.indexOf(":"))
			conversion=conversion.substring(conversion.indexOf(":")+1)

			var fromu = units[conversion.substring(0,conversion.indexOf(":"))]
			conversion=conversion.substring(conversion.indexOf(":")+1)

			var tou = units[conversion.substring(0,conversion.indexOf(":"))]
			conversion=conversion.substring(conversion.indexOf(":")+1)

			var val = conversion

			logAdd(amount, fromu, tou, val);
		}
	}
}

var acFrom = new AutoComplete('fromUnits', allFromUnits)
acFrom.maxRows=40
acFrom.highliteFirstMatch=true
acFrom.openOnEmptyText=true
var acTo = new AutoComplete('toUnits', toUnits)
acTo.openOnEmptyText=true
acTo.maxRows=20
acTo.highliteFirstMatch=true

function swapFromTo()
{
	var f = document.getElementById("fromUnits")
	var t = document.getElementById("toUnits")
	var tmp = f.value
	f.value = t.value
	t.value = tmp
	compute()
}