local hex = {}
local getArgs = require("Module:Arguments").getArgs
local RESOLUTION = 12 -- I have no idea how many places the floating point is good to, this is just a guess.
-- initialize conversion arrays; these should remain in scope for individual conversions
local d2h = mw.loadData("Module:Hex/data table")
-- functions for other modules to use
-- internal one-byte lookups
hex._d2hbyte = function(val)
-- assumes decimal is a number
return d2h[val] or '00'
end
hex._h2dbyte = function(val)
-- assumes hex is a string
return tonumber('0x' .. val)
end
-- internal multi-byte lookups
hex._d2h = function(val, integer)
local negative -- true if number is negative
if ("string" == type(val)) then
integer = integer or (not mw.ustring.match(val, "[%.%,]"))
val = tonumber(val) or error('bad value for Module:hex._d2h')
-- decimal input can be string, but is required to read as a floating point number for now
-- as a safeguard, integer as argument or through lack of a "." or "," [not sure if the latter is possible] prevents fractions
end
if val<0 then
val = 0 - val
negative = true
end
local whole = math.floor(val)
local fraction = val - whole
local output = "" -- will be made big-endian by adding at the start
repeat
local littlest, bigger = whole % 256, math.floor(whole / 256)
output = hex._d2hbyte(littlest) .. output
whole = bigger
until (0 == whole)
if negative then output = "-" .. output end
if (not (integer and (fraction > 0))) then
return output
end
-- do fractional conversion to hex
output = output .. "."
local count = RESOLUTION -- makes sure it doesn't loop endlessly from hallucinatory floating point data or repeating fraction
while (fraction > 0) and (count > 0) do
local shift = fraction * 256
local biggest, littler = math.floor(shift), (shift) % 1
output = output .. hex._d2hbyte(biggest)
fraction = shift
count = count - 1
end
return output
end
local trim = function(text)
return mw.ustring.gsub(text, "[^0-9A-Fa-f]", "")
end
hex._h2d = function(val)
decwhole = 0
if ('string' ~= type(val)) then error("hexadecimal value should be text") end
local whole, fraction = mw.ustring.match(val, "(.-)%.(.-)")
whole = whole or val
fraction = fraction or ""
negative = mw.ustring.match(whole, "%-")
whole, fraction = trim(whole), trim(fraction)
if 1 == (#whole % 2) then whole = "0" .. whole end
if 1 == (#fraction %2) then fraction = fraction .. "0" end
-- these assume an even number of digits now exist!
while (#whole > 0) do
decwhole = decwhole * 256 + hex._h2dbyte(string.sub(whole, 1, 2))
whole = string.sub(whole, 3, -1)
end
local decfraction = 0
while (#fraction > 0) do
decfraction = (decfraction + hex._h2dbyte(string.sub(decfraction, -2, -1)))/256
fraction = string.sub(fraction, 1, -3)
end
return ((negative and -1) or 1)*(decwhole + decfraction)
end
hex._even = function(text)
if (#text % 2 == 1) then
text = "0" .. text
end
return text
end
hex._hexstring = function(text)
text = mw.text.trim(text)
text = mw.ustring.gsub(text, "%X", "")
text = hex._even(text)
local output = {}
for i = 1, #text/2 do
table.insert(output, string.char(hex._h2dbyte(string.sub(text, i*2-1, i*2))))
end
return table.concat(output, "")
end
hex._unicode = function(text)
text = mw.ustring.gsub(text, "%X+", " ")
text = mw.text.trim(text)
-- the rule is that any contiguous group of hex digits is one unicode point
-- so U+2022 +2023 2024 is three chars, but U+20 22 is two chars, sorry
prowl = string.gmatch(text, "%x+")
output = {}
utf = ""
local prefix
repeat
group = prowl()
if group then
-- convert group to UTF8 hex bytes; then hexstring the hex bytes
local outgroup = ""
local bytes
groupval = hex._h2d(group)
if (groupval < 128) then
prefix = 0
bytes = 1
elseif (groupval < 2048) then
prefix = 192
bytes = 2
elseif (groupval < 65536) then
prefix = 224
bytes = 3
elseif (groupval < 2097152) then
prefix = 240
bytes = 4
elseif (groupval < 1073741824) then
prefix = 248
bytes = 5
elseif (groupval < 34359738368) then
prefix = 252
bytes = 6
else
error ("[[Module:Hex]] received invalid UTF8")
end
repeat
local outbyte = groupval % 64
groupval = math.floor(groupval/64)
if (#outgroup == bytes - 1) then
outbyte = outbyte + prefix
else
outbyte = outbyte + 128
end
outgroup = string.char(outbyte) .. outgroup
until (#outgroup >= bytes)
table.insert(output, outgroup)
end
until not group
return table.concat(output, "")
end
hex._hexdump = function(text)
local output = {}
local stringtable = {string.byte(text, 1, 7500)} -- empirically determined in a sandbox as 7997 to avoid stack error
for i = 1, #stringtable do
local caption = string.sub(text,i,i)
if caption == " " then caption = " " end
table.insert(output, '<div style="position:relative;display:inline;">'..(hex._d2hbyte(stringtable[i]) or "`")..'<span style="position:absolute;color:red;top:-11px;left:3px;font-size:85%;">' .. caption .. '</span></div>')
end
return table.concat(output, " ")
end
-- template front doors
hex.d2h = function(frame)
local args = getArgs(frame)
return hex._d2h(args.val or args[1], args.integer)
end
hex.h2d = function(frame)
local args = getArgs(frame)
return hex._h2d(args.val or args[1])
end
hex.hexstring = function(frame)
local args = getArgs(frame)
return hex._hexstring(args.val or args[1])
end
hex.unicode = function(frame)
local args = getArgs(frame)
return hex._unicode(args.val or args[1])
end
hex.hexdump = function(frame)
local args = getArgs(frame)
local text = args.text or args[1] or ""
local nowiki = args.nowiki
if args.transclude then -- you can't just do this in the parameter, or it will evaluate it before sending it!
text = "{{" .. text .. "}}"
end
if args.preprocess then -- for some transclusions, this will return a strip marker
text = frame:preprocess(text)
end
if args.unstrip then -- and if so, then this will return the HTML that marker would reveal
text = mw.text.unstrip(text)
end
if (not args.plain) then -- as a "control", plain returns the text as it would appear without dump
text = hex._hexdump(text or "")
end
if nowiki then
text = frame:preprocess("<nowiki><pre>" .. text .. "</pre></nowiki>")
end
text = "<code>" .. text .. "</code>"
return text
end
return hex
