Module:BaseConvert

local p = {}

local digits = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ'

function normalizeFullWidthChars(s)

   return mw.ustring.gsub(s, '[！-～]', function(s) 
       return mw.ustring.char(mw.ustring.codepoint(s, 1) - 0xFEE0) 
   end)    

end

function _convert(n, base, from, precision, width, default, prefix, suffix)

   n =  .. n   -- convert to a string
   
   -- strip off any leading '0x' (unless x is a valid digit in the input base)
   from = tonumber(from)
   if not from or from < 34 then
       local c
       n, c = n:gsub('^(-?)0[Xx]', '%1')
       if c > 0 and not from then from = 16 end
   end

   -- check for a negative sign. Do this while the input is still in string form,
   -- because tonumber doesn't support negative numbers in non-10 bases.
   local sign = 
   local c
   n, c = n:gsub('^-', )
   if c > 0 then sign = '-' end
   
   -- replace any full-width Unicode characters in the string with their ASCII equivalents
   n = normalizeFullWidthChars(n)
   
   -- handle scientific notation with whitespace around the 'e' e.g. '5 e7'
   n = n:gsub('%s*[eE]%s*', 'e')
   
   from = from or 10
   local num = tonumber(n, from)
   base = tonumber(base)
   precision = tonumber(precision)
   width = tonumber(width)
   
   if not num or not base then return default or n end
   
   local i, f = math.modf(num)

   local t = {}
   repeat
       local d = (i % base) + 1
       i = math.floor(i / base)
       table.insert(t, 1, digits:sub(d, d))
   until i == 0
   while #t < (width or 0) do
       table.insert(t, 1, '0') 
   end
   local intPart = table.concat(t, )
   
   -- compute the fractional part
   local tf = {}
   while f > 0 and #tf < (precision or 10) do
       f = f * base
       i, f = math.modf(f)
       table.insert(tf, digits:sub(i + 1, i + 1))
   end
   
   -- add trailing zeros if needed
   if precision and #tf < precision then
       for i = 1, precision - #tf do
           table.insert(tf, '0') 
       end
   end

   fracPart = table.concat(tf, )
   
   -- remove trailing zeros if not needed
   if not precision then
       fracPart = fracPart:gsub('0*$', )
   end
   
   -- add the radix point if needed
   if #fracPart > 0 then
       fracPart = '.' .. fracPart
   end
   
   return (prefix or ) .. sign .. intPart .. fracPart .. (suffix or )

end

function p.convert(frame)

   -- Allow for invocation via #invoke or directly from another module
   local args
   if frame == mw.getCurrentFrame() then
       args = frame.args
   else
       args = frame
   end
   
   local n = args.n
   local base = args.base
   local from = args.from
   local precision = args.precision
   local width = args.width
   local default = args.default
   local prefix = args.prefix
   local suffix = args.suffix
   return _convert(n, base, from, precision, width, default, prefix, suffix)

end

return p