--[[
  StringX v2.3.1 [Updated: 8 Feb 2013]
  
  Copyright © 2013-2014 Joshua Asbury a.k.a. theoriginalbit [theoriginalbit@gmail.com]

  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, and/or sublicense copies
  of the Software, and to permit persons to whom the Software is furnished to
  do so, subject to the following conditions:

  - The above copyright notice and this permission notice shall be included in
    all copies or substantial portions of the Software;
  - Visible credit is given to the original author;
  - The software is distributed in a non-profit way;

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  THE SOFTWARE.
--]]

--[[
Java methods from http://docs.oracle.com/javase/6/docs/api/java/lang/String.html
]]--

function charAt( str, index )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( index ) ~= "number" then error( "Bad argument: Number expected, got "..type( index ), 2 ) end
	if index < 1 or index > #str then error( "Bad argument: Index out of bounds: "..index, 2 ) end
	return str:sub( index, index )
end

function compareTo( oneString, anotherString )
	if type( oneString ) ~= "string" then error( "Bad argument: String expected, got "..type( oneString ), 2 ) end
	if type( anotherString ) ~= "string" then error( "Bad argument: String expected, got "..type( anotherString ), 2 ) end
	return oneString == anotherString and 0 or oneString:len() - anotherString:len()
end

function compareToIgnoreCase( oneString, anotherString )
	if type( oneString ) ~= "string" then error( "Bad argument: String expected, got "..type( oneString ), 2 ) end
	if type( anotherString ) ~= "string" then error( "Bad argument: String expected, got "..type( anotherString ), 2 ) end
	return oneString:lower() == anotherString:lower() and 0 or oneString:len() - anotherString:len()
end

function concat( oneString, anotherString )
	if type( oneString ) ~= "string" then error( "Bad argument: String expected, got "..type( oneString ), 2 ) end
	if type( anotherString ) ~= "string" then error( "Bad argument: String expected, got "..type( anotherString ), 2 ) end
	return oneString..anotherString
end

function contains( str, seq )
	if type( str ) == nil then error( "Bad argument: Value expected, got nil", 2 ) end
	str = tostring(str)
	local sStart, sEnd, sStr = str:find( seq, 1 )
	return sStart ~= nil
end

function contentEquals( str, tData )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( tData ) ~= "table" then error( "Bad argument: Table expected, got "..type( tData ), 2 ) end
	return str == table.concat( tData )
end

function copyValueOf( tData )
	if type( tData ) ~= "table" then error( "Bad argument: Table expected, got "..type( tData ), 2 ) end
	return table.concat( tData )
end


function copySubsetOf( tData, offset, count )
	if type( tData ) ~= "table" then error( "Bad argument: Table expected, got "..type( tData ), 2 ) end
	if type( offset ) ~= "number" then error( "Bad argument: Number expected, got "..type( offset ), 2 ) end
	if type( count ) ~= "number" then error( "Bad argument: Number expected, got "..type( count ), 2 ) end
	if offset + count - 1 > #tData then error( "Bad argument: Index out of bounds: "..( offset + count - 1), 2 ) end
	return table.concat( tData, "", offset, offset + count - 1 )
end

function endsWith( str, suffix )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return str:sub( str:len() - suffix:len() + 1) == tostring( suffix )
end

function equals( str, value )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return str == tostring( value )
end

function equalsIgnoreCase( oneStr, anotherStr )
	if type( oneStr ) ~= "string" then error( "Bad argument: String expected, got "..type( oneStr ), 2 ) end
	if type( anotherStr ) ~= "string" then error( "Bad argument: String expected, got "..type( anotherStr ), 2 ) end
	
	return oneStr:lower() == anotherStr:lower()
end

function getBytes( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return { string.byte(str, 1, #str) }
end

function getChars( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	local chars = {}
	for i = 1, str:len() do
		chars[i] = str:sub( i, i )
	end
	return chars
end

--[[
http://docs.oracle.com/javase/6/docs/api/java/lang/String.html#hashCode()

Returns a hash code for this string. The hash code for a String object is computed as

	s[0]*31^(n-1) + s[1]*31^(n-2) + ... + s[n-1]
 
using int arithmetic, where s[i] is the ith character of the string, n is the length of the string, and ^ indicates exponentiation. (The hash value of the empty string is zero.)
]]--

function hashCode( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	local int = 0
	for i = 1, #str do
		int = int + str:byte( i ) * ( 31 ^ ( #str - i ) )
	end
	return int
end

function indexOf( str, ch )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	ch = tostring( ch )
	if #ch > 1 then error( "Bad argument: Char expected, got string, consider using indexOfSubstring if intentional", 2 ) end
	for i = 1, #str do
		if str:sub( i, i ) == ch then
			return i
		end
	end
	return nil
end

function indexOfAfter( str, ch, index )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( index ) ~= "number" then error( "Bad argument: Number expected, got "..type( index ), 2 ) end
	ch = tostring( ch )
	if #ch > 1 then error( "Bad argument: Char expected, got string, consider using indexOfSubstring if intentional", 2 ) end
	for i = index + 1, #str do
		if str:sub( i, i ) == ch then
			return i
		end
	end
	return nil
end

function indexOfSubstring( str, sub )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	sub = tostring( sub )
	local sStart, sEnd, sStr = str:find( sub, 1 )
	return sStart
end

function indexOfSubstringFrom( str, sub, index )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( index ) ~= "number" then error( "Bad argument: Number expected, got "..type( index ), 2 ) end
	sub = tostring( sub )
	local sStart, sEnd, sStr = str:find( sub, index + 1 )
	return sStart
end

function isEmpty( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return #str == 0
end

function lastIndexOf( str, ch )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	ch = tostring( ch )
	if #ch > 1 then error( "Bad argument: Char expected, got string", 2 ) end
	for i = #str, 1, -1 do
		if str:sub( i, i) == ch then
			return i
		end
	end
	return nil
end

function lastIndexOfFrom( str, ch, index )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	ch = tostring( ch )
	if #ch > 1 then error( "Bad argument: Char expected, got string", 2 ) end
	if type( index ) ~= "number" then error( "Bad argument: Number expected, got "..type( index ), 2 ) end
	for i = index - 1, 1, -1 do
		if str:sub( i, i) == ch then
			return i
		end
	end
	return nil
end

function lastIndexOfSubstring( str, sub )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	sub = tostring( sub )
	for i = #str - #sub, 1, -1 do
		local s = str:sub( i, i + #sub - 1 )
		if s == sub then
			return i
		end
	end
	return nil
end

function lastIndexOfSubstringFrom( str, sub, index )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	sub = tostring( sub )
	if type( index ) ~= "number" then error( "Bad argument: Number expected, got "..type( index ), 2 ) end
	for i = #str - (#str - index) - #sub - 1, 1, -1 do
		local s = str:sub( i, i + #sub - 1 )
		if s == sub then
			return i
		end
	end
	return nil
end

function regionMatches( str, sOffset, other, oOffset, len)
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( other ) ~= "string" then error( "Bad argument: String expected, got "..type( other ), 2 ) end
	if type( sOffset ) ~= "number" then error( "Bad argument: Number expected, got "..type( sOffset ), 2 ) end
	if type( oOffset ) ~= "number" then error( "Bad argument: Number expected, got "..type( oOffset ), 2 ) end
	if type( len ) ~= "number" then error( "Bad argument: Number expected, got "..type( len ), 2 ) end
	if sOffset > #str then error( "Bad argument: Offset cannot be larger than string length", 2 ) end
	if oOffset > #other then error( "Bad argument: Offset cannot be larger than string length", 2 ) end
	if len > #str or len > #other then error( "Bad argument: Length cannot be longer than the shortest string", 2 ) end
	return ( str:sub( sOffset, sOffset ) == other:sub( oOffset, oOffset ) )
end
	
function replace( str, old, new )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	old = tostring( old )
	new = tostring( new )
	local nStr, count = str:gsub( old, new )
	return nStr
end

function replaceFirst( str, old, new )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	old = tostring( old )
	new = tostring( new )
	local nStr, count = str:gsub( old, new, 1 )
	return nStr
end

function split( str, regex )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( regex ) ~= "string" then error( "Bad argument: String expected, got "..type( regex ), 2 ) end
	local t = {}
	regex = "[^"..regex.."]+"
	for s in str:gmatch(regex) do
		t[#t+1] = s
	end
	return t
end

function splitLimit( str, regex, lim )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( regex ) ~= "string" then error( "Bad argument: String expected, got "..type( regex ), 2 ) end
	if type( lim ) ~= "number" then error( "Bad argument: Number expected, got "..type( lim ), 2 ) end
	local t = { }
	local fpat = "(.-)"..regex
	local last_end = 1
	local s, e, cap = str:find(fpat, 1)
	while s do
		if #t == lim - 1 then
			break
		end
		if s ~= 1 or cap ~= "" then
			table.insert(t,cap)
		end
		last_end = e+1
		s, e, cap = str:find(fpat, last_end)
	end
	if last_end <= #str then
		cap = str:sub(last_end)
		table.insert(t, cap)
	end
	return t
end

function startsWith( str, prefix )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	prefix = tostring( prefix )
	return str:sub( 1, prefix:len()) == prefix
end

function subSequence( str, beginIndex, endIndex )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( beginIndex ) ~= "number" then error( "Bad argument: Number expected, got "..type( beginIndex ), 2 ) end
	if type( endIndex ) ~= "number" then error( "Bad argument: Number expected, got "..type( endIndex ), 2 ) end
	local t = {}
	for i = beginIndex, endIndex do
		table.insert( t, str:sub( i, i ) )
	end
	return t
end

function toCharTable( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return getChars( str )
end

function trim( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return (str:gsub("^%s*(.-)%s*$", "%1"))
end

function valueOf( tData )
	if type( tData ) ~= "table" then error( "Bad argument: Table expected, got "..type( tData), 2 ) end
	return table.concat( tData )
end

function valueOfWith( tData, offset, count )
	if type( tData ) ~= "table" then error( "Bad argument: Table expected, got "..type( tData), 2 ) end
	if offset == 0 then error( "Bad argument: Table index out of bounds: index "..offset, 2) end
	if offset > #tData then error( "Bad argument: Table index out of bounds: index "..offset.." length "..#tData , 2) end
	if count == nil then count = #tData - offset + 1 end
	if offset + count > #tData + 1 then error( "Bad argument: Offset + Count cannot be larger than table length", 2 ) end
	return table.concat( tData, "", offset, offset + count - 1 )
end


--[[
C# Methods from http://msdn.microsoft.com/en-us/library/system.string.aspx
]]--

function isWhitespace( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if str == "" then return false end
	return trim( str ) == ""
end

function padLeft( str, count )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( count ) ~= "number" then error( "Bad argument: Number expected, got "..type( count ), 2 ) end
	count = math.floor( count )
	return string.rep( " ", count )..str
end

function padLeftWith( str, count, char )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( count ) ~= "number" then error( "Bad argument: Number expected, got "..type( count ), 2 ) end
	if type( char ) ~= "string" then error( "Bad argument: String expected, got "..type( char ), 2 ) end
	if #char > 1 then error( "Bad argument: Char expected, got string", 2 ) end
	count = math.floor( count )
	return string.rep( char, count )..str
end

function padRight( str, count )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( count ) ~= "number" then error( "Bad argument: Number expected, got "..type( count ), 2 ) end
	count = math.floor( count )
	return str..string.rep( " ", count )
end

function padRightWith( str, count, char )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( count ) ~= "number" then error( "Bad argument: Number expected, got "..type( count ), 2 ) end
	if type( char ) ~= "string" then error( "Bad argument: String expected, got "..type( char ), 2 ) end
	if #char > 1 then error( "Bad argument: Char expected, got string", 2 ) end
	count = math.floor( count )
	return str..string.rep( char, count )
end

function trimEnd( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return (str:gsub("^(.-)%s*$", "%1"))
end

function trimStart( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return (str:gsub("^%s*(.-)", "%1"))
end

--[[
Objective-C Methods from http://developer.apple.com/library/mac/#documentation/Cocoa/Reference/Foundation/Classes/NSString_Class/Reference/NSString.html#//apple_ref/doc/uid/TP40003744
]]--

function stringWithContentsOfFile( path )
	if type( path ) ~= "string" then error( "Bad argument: String expected, got "..type( path ), 2 ) end
	if not fs.exists( path ) then error( "Bad argument: File does not exist at path: "..path, 2 ) end
	if fs.isDir( path ) then error( "Bad argument: Not a file at path: "..path, 2 ) end
	
	local file = io.open( path, "r" )
	local contents = file:read("*a")
	file:close()
	
	return contents
end

function stringWithContentsOfURL( url )
	if type( url ) ~= "string" then error( "Bad argument: String expected, got "..type( url ), 2 ) end
	url = textutils.urlEncode( url )
	
	http.request( url )
	
	local event = nil
	while true do
		event = { os.pullEventRaw() }
		
		if (event[1] == "http_success") then
                    break
		elseif (event[1] == "http_failure") then
			return "No response from server."
		end
	end
	
	return event[3].readAll()
end

function writeToFile( str, path )
	if type( path ) ~= "string" then error( "Bad argument: String expected, got "..type( path ), 2 ) end
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	
	local file = io.open( path, "w" )
	file:write( str )
	file:close()
end

function characterAtIndex( str, index )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( index ) ~= "number" then error( "Bad argument: Number expected, got "..type( index ), 2 ) end
	if index < 1 or index > #str then error( "Bad argument: Index out of bounds: "..index, 2 ) end
	return charAt( index, index )
end

function getCharacters( str, range )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return getChars( str )
end

function componentsSeparatedByString( str, sub )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( sub ) ~= "string" then error( "Bad argument: String expected, got "..type( sub ), 2 ) end
	return split( str, sub )
end

function substringFromIndex( str, index )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( index ) ~= "number" then error( "Bad argument: Number expected, got "..type( index ), 2 ) end
	if index < 1 or index > #str then error( "Bad argument: Index out of bounds: "..index, 2 ) end
	return str:sub( index )
end

function substringToIndex( str, index )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( index ) ~= "number" then error( "Bad argument: Number expected, got "..type( index ), 2 ) end
	if index < 1 or index > #str then error( "Bad argument: Index out of bounds: "..index, 2 ) end
	return str:sub( 1, index - 1 )
end

function substringWithRange( str, index, len )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( index ) ~= "number" then error( "Bad argument: Number expected, got "..type( index ), 2 ) end
	if index < 1 or index > #str then error( "Bad argument: Index out of bounds: "..index, 2 ) end
	if index + len - 1 > #str then error( "Bad argument: Index + Length out of bounds: "..index, 2 ) end
	return str:sub( index, index + len )
end

function rangeOfString( str, sub )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	sub = tostring( sub )
	local sStart, sEnd, sStr = str:find( sub, 1 )
	return sStart, ( sEnd - sStart )
end

function rangeOfStringWithinRange( str, sub, index, len )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( index ) ~= "number" then error( "Bad argument: Number expected, got "..type( index ), 2 ) end
	if index < 1 or index > #str then error( "Bad argument: Index out of bounds: "..index, 2 ) end
	if index + len - 1 > #str then error( "Bad argument: Index + Length out of bounds: "..index, 2 ) end
	sub = tostring( sub )
	local sStart, sEnd, sStr = str:find( sub, index + 1 )
	return ( sStart > index + len - 1 ) and nil, nil or sStart, ( sEnd - sStart )
end

function stringByReplacingOccurrencesOfStringWithString( str, old, new )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	old = tostring( old )
	new = tostring( new )
	local nStr, count = str:gsub( old, new )
	return nStr
end

function capitalizedString( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	local nStr, count = str:gsub("(%a)([%w_']*)", function(first, rest) return first:upper()..rest:lower() end )
	return nStr
end

function uppercaseString( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return str:upper()
end

function lowercaseString( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return str:lower()
end

function intValue( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	local num = tonumber( str )
	return math.floor( num )
end

function boolValue( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if str:lower() == "true" then
		return true
	elseif str:lower() == "false" then
		return false
	else
		return nil
	end
end

function pathComponents( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	local c = componentsSeparatedByString( str, "/" )
	local ret = {}
	if startsWith( str, "/" ) then table.insert( ret, "/" ) end
	for i = 1, #c do
		table.insert( ret, c[i] )
	end
	return ret
end

function lastPathComponent( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	local components = pathComponents( str )
	return components[ #components ]
end

function isAbsolutePath( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	local r = shell.resolve( str )
	return str == ( startsWith( r, "/" ) ) and r or "/"..r
end

function pathExtension( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	local file = lastPathComponent( str )
	if not contains( file, "%." ) then return "" end
	local ext = componentsSeparatedByString( file, "%." )
	return ext[ #ext ]
end

function stringByAppendingPathComponent( str, comp )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( comp ) ~= "string" then error( "Bad argument: String expected, got "..type( comp ), 2 ) end
	nStr = str
	if nStr ~= "" then
		if not endsWith( nStr, "/" ) then
			nStr = nStr.."/"
		end
	end
	return nStr..comp
end

function stringByAppendingPathExtension( str, ext )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( ext ) ~= "string" then error( "Bad argument: String expected, got "..type( ext ), 2 ) end
	if endsWith( str, "/" ) then
		str = str:sub( 1, #str - 1 )
	end
	return str..( contains( ext, "%." ) and "" or ".")..ext
end

function stringByDeletingLastPathComponent( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if str == "/" then
		return str
	end
	if contains( str, "/" ) then
		local path = componentsSeparatedByString( str, "/" )
		return "/"..table.concat( path, "/", 1, #path - 1 )
	else
		return ""
	end
end

function stringByDeletingPathExtension( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if str == "/" then
		return str
	end
	if endsWith( str, "/" ) then
		str = str:sub( 1, #str - 1)
	end
	if contains( str, "%." ) then
		local s = replace( str, "."..pathExtension( str ), "" )
		if s == "" then
			return str
		else
			return s
		end
	else
		return str
	end
end

function stringByAddingPercentEscapes( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	str = string.gsub (str, "\n", "\r\n")
	str = string.gsub (str, "([^%w ])", function (c) return string.format ("%%%02X", string.byte(c)) end )
	str = string.gsub (str, " ", "+")
	return str
end

function stringByReplacingPercentEscapes( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	str = string.gsub (str, "+", " ")
	str = string.gsub (str, "%%(%x%x)", function(h) return string.char(tonumber(h,16)) end)
	str = string.gsub (str, "\r\n", "\n")
	return str
end

--[[
Following have been added for some ease of use but are not in the Java String class
]]--


function containsIgnoreCase( str, seq )
	if type( str ) == nli then error( "Bad argument: Value expected, got nil", 2 ) end
	str = tostring(str):lower()
	return contains( str, seq:lower() )
end

function startsWithIgnoreCase( str, prefix )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	prefix = tostring( prefix )
	
	return startsWith( str:lower(), prefix:lower() )
end

function endsWithIgnoreCase( str, suffix )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	suffix = tostring( suffix )
	
	return endsWith( str:lower(), suffix:lower() )
end

function regionMatchesIgnoreCase( str, sOffset, other, oOffset, len)
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( other ) ~= "string" then error( "Bad argument: String expected, got "..type( other ), 2 ) end
	if type( sOffset ) == nil then sOffset = 1 end
	if type( sOffset ) ~= "number" then error( "Bad argument: Number expected, got "..type( sOffset ), 2 ) end
	if type( oOffset ) == nil then oOffset = 1 end
	if type( oOffset ) ~= "number" then error( "Bad argument: Number expected, got "..type( oOffset ), 2 ) end
	if type( len ) ~= "number" then error( "Bad argument: Number expected, got "..type( len ), 2 ) end
	
	return regionMatches( str:lower(), sOffset, other:lower(), oOffset, len )
end

function sentenceCase( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	local nStr, count = str:gsub("%a", string.upper, 1)
	return nStr
end

function titleCase( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	local nStr, count = str:gsub("(%a)([%w_']*)", function(first, rest) return first:upper()..rest:lower() end )
	return nStr
end

function splitLineToTable( str, width )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( width ) ~= "number" then error( "Bad argument: Number expected, got "..type( width ), 2 ) end
	if width < 1 then error( "Bad argument: Width must be positive", 2 ) end
	local currLine = ""
	local words = split( str, " " )
	local t = {}
	for i = 1, #words do
		if #currLine + #words[i] + 1 > width then
			table.insert( t, currLine )
			currLine = words[i].." "
		else
			currLine = currLine..words[i].." "
		end
		
		if i == #words then table.insert( t, currLine ) end
	end
	
	return t
end

function splitLine( str, width )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( width ) ~= "number" then error( "Bad argument: Number expected, got "..type( width ), 2 ) end
	if width < 1 then error( "Bad argument: Width must be positive", 2 ) end
	return table.concat( splitLineToTable( str, width ), "\n" )
end

function count( str, regex )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( regex ) ~= "string" then error( "Bad argument: String expected, got "..type( regex ), 2 ) end
	local count = 0
	local fpat = "(.-)"..regex
	local last_end = 1
	local s, e, cap = str:find(fpat, last_end)
	while s do
		count = count + 1
		last_end = e+1
		s, e, cap = str:find(fpat, last_end)
	end
	return count
end

function countIgnoreCase( str, regex )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	if type( regex ) ~= "string" then error( "Bad argument: String expected, got "..type( regex ), 2 ) end
	str = str:lower()
	local count = 0
	local fpat = "(.-)"..regex:lower()
	local last_end = 1
	local s, e, cap = str:find(fpat, last_end)
	while s do
		count = count + 1
		last_end = e+1
		s, e, cap = str:find(fpat, last_end)
	end
	return count
end

function isLower( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return (str:find("%L")) == nil
end

function isUpper( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return (str:find("%U")) == nil
end

function isAlpha( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return (str:find("%A")) == nil
end

function isAlphaNumeric( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return (str:find("%W")) == nil
end

function isNumeric( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return (str:find("%D")) == nil
end

function isPunctuation( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return (str:find("%P")) == nil
end

function isHexadecimal( str )
	if type( str ) ~= "string" then error( "Bad argument: String expected, got "..type( str ), 2 ) end
	return (str:find("%X")) == nil
end