lotj_colors.lua

local BLACK = 1
local RED = 2
local GREEN = 3  
local YELLOW = 4 
local BLUE = 5 
local MAGENTA = 6 
local CYAN = 7 
local WHITE = 8
local DEFAULT_COLOUR = "&w"

function init_ansi()
   -- map from color values to aardwolf color codes
   conversion_colours = {
      [GetNormalColour (BLACK)]   = "&x",
      [GetNormalColour (RED)]     = "&r",
      [GetNormalColour (GREEN)]   = "&g",
      [GetNormalColour (YELLOW)]  = "&O",
      [GetNormalColour (BLUE)]    = "&b",
      [GetNormalColour (MAGENTA)] = "&p",
      [GetNormalColour (CYAN)]    = "&c",
      [GetNormalColour (WHITE)]   = "&w",
      [GetBoldColour   (BLACK)]   = "&z", -- gray
      [GetBoldColour   (RED)]     = "&R",
      [GetBoldColour   (GREEN)]   = "&G",
      [GetBoldColour   (YELLOW)]  = "&Y",
      [GetBoldColour   (BLUE)]    = "&B",
      [GetBoldColour   (MAGENTA)] = "&P",
      [GetBoldColour   (CYAN)]    = "&C",
      [GetBoldColour   (WHITE)]   = "&W",
   }  -- end conversion table
     
   -- This table uses the colours as defined in the MUSHclient ANSI tab, however the
   -- defaults are shown on the right if you prefer to use those.

   -- map from lotj color codes to color values
   colour_conversion = {
      x = GetNormalColour (BLACK)   ,   -- 0x000000 
      r = GetNormalColour (RED)     ,   -- 0x000080 
      g = GetNormalColour (GREEN)   ,   -- 0x008000 
      O = GetNormalColour (YELLOW)  ,   -- 0x008080 
      b = GetNormalColour (BLUE)    ,   -- 0x800000 
      p = GetNormalColour (MAGENTA) ,   -- 0x800080 
      c = GetNormalColour (CYAN)    ,   -- 0x808000 
      w = GetNormalColour (WHITE)   ,   -- 0xC0C0C0 
      z = GetBoldColour   (BLACK)   ,   -- 0x808080 
      R = GetBoldColour   (RED)     ,   -- 0x0000FF 
      G = GetBoldColour   (GREEN)   ,   -- 0x00FF00 
      Y = GetBoldColour   (YELLOW)  ,   -- 0x00FFFF 
      B = GetBoldColour   (BLUE)    ,   -- 0xFF0000 
      P = GetBoldColour   (MAGENTA) ,   -- 0xFF00FF 
      C = GetBoldColour   (CYAN)    ,   -- 0xFFFF00 
      W = GetBoldColour   (WHITE)   ,   -- 0xFFFFFF
   }  -- end conversion table

   -- Set up xterm color conversions using the extended_colours global array
   for i = 1,8 do
      colour_conversion[string.format("%03d",i-1)] = GetNormalColour(i)
      colour_conversion[string.format("%02d",i-1)] = GetNormalColour(i)
      colour_conversion[string.format("%d",i-1)] = GetNormalColour(i)
   end
   for i = 8,15 do
      colour_conversion[string.format("%03d",i)] = GetBoldColour(i-7)
      colour_conversion[string.format("%02d",i)] = GetBoldColour(i-7)
      colour_conversion[string.format("%d",i)] = GetBoldColour(i-7)
   end

   ANSI_colours = {
      [GetNormalColour (BLACK)]   = ANSI(0,30),
      [GetNormalColour (RED)]     = ANSI(0,31),
      [GetNormalColour (GREEN)]   = ANSI(0,32),
      [GetNormalColour (YELLOW)]  = ANSI(0,33),
      [GetNormalColour (BLUE)]    = ANSI(0,34),
      [GetNormalColour (MAGENTA)] = ANSI(0,35),
      [GetNormalColour (CYAN)]    = ANSI(0,36),
      [GetNormalColour (WHITE)]   = ANSI(0,37),
      [GetBoldColour   (BLACK)]   = ANSI(1,30),
      [GetBoldColour   (RED)]     = ANSI(1,31),
      [GetBoldColour   (GREEN)]   = ANSI(1,32),
      [GetBoldColour   (YELLOW)]  = ANSI(1,33),
      [GetBoldColour   (BLUE)]    = ANSI(1,34),
      [GetBoldColour   (MAGENTA)] = ANSI(1,35),
      [GetBoldColour   (CYAN)]    = ANSI(1,36),
      [GetBoldColour   (WHITE)]   = ANSI(1,37)
   }  -- end conversion table
end

init_ansi()

for i = 16,255 do
   local xterm_colour = extended_colours[i]
   conversion_colours[xterm_colour] = (conversion_colours[xterm_colour] or string.format("&%03d",i))
   colour_conversion[string.format("%03d",i)] = xterm_colour
   colour_conversion[string.format("%d",i)] = xterm_colour
end

-- Aardwolf bumps a few very dark xterm colors to brighter values to improve visibility
for i = 232,237 do
   colour_conversion[string.format("%d",i)] = extended_colours[238]
end
for i = 17,19 do
   colour_conversion[string.format("%03d",i)] = extended_colours[19]
   colour_conversion[string.format("%d",i)] = extended_colours[19]
end

-- also provide the reverse of the extended_colours global table
colours_extended = {}
for i,v in ipairs(extended_colours) do
   colours_extended[v] = i
end

-- Convert a line of style runs into color codes.
-- The caller may optionally choose to start and stop at arbitrary character indices.
-- Negative indices are measured back from the end.
-- The order of start and end columns does not matter, since the start will always be lower than the end.
function StylesToColoursOneLine (styles, startcol, endcol)
   local startcol = startcol or 1
   local endcol = endcol or 99999 -- 99999 is assumed to be long enough to cover ANY style run
   
   -- negative column indices are used to measure back from the end
   if startcol < 0 or endcol < 0 then
      local total_chars = 0
      for k,v in ipairs(styles) do
         total_chars = total_chars + v.length
      end
      if startcol < 0 then
         startcol = total_chars + startcol + 1
      end
      if endcol < 0 then
         endcol = total_chars + endcol + 1
      end
   end

   -- start/end order does not matter when calling this function
   if startcol > endcol then
      startcol, endcol = endcol, startcol
   end

   local copystring = ""
   
   -- skip unused style runs at the start
   local style_start = 0
   local first_style = 0
   local last_style = 0
   for k,v in ipairs(styles) do
      if startcol <= style_start+v.length then
         first_style = k
         startcol = startcol - style_start
         break
      end
      style_start = style_start+v.length
   end
      
   -- startcol larger than the sum length of all styles? return empty string
   if first_style == 0 then 
      return copystring 
   end
   
   for i = first_style,#styles do
      local v = styles[i]
      local text = string.sub(v.text, startcol, endcol - style_start)

      -- fixup string: change & to && and ~ to &-
      text = string.gsub(string.gsub(text, "&", "&&"),"~", "&-")
      
      local code = conversion_colours[v.textcolour]
      if code then
         copystring = copystring..code..text
      else
         copystring = copystring..text
      end
      
      -- stopping here before the end?
      if endcol <= style_start + v.length then
         break
      end
      
      -- all styles after the first one have startcol of 1
      startcol = 1
      style_start = style_start + v.length
   end
   return copystring
end -- StylesToColoursOneLine

-- converts text with colour codes in it into style runs
function ColoursToStyles (Text)
   if Text:match ("&") then
      astyles = {}

      Text = Text:gsub ("&%-", "~") -- fix tildes
      Text = Text:gsub ("&&", "\0") -- change && to 0x00
      Text = Text:gsub ("&[3-9]%d%d","") -- strip invalid xterm codes (300+)
      Text = Text:gsub ("&2[6-9]%d","") -- strip invalid xterm codes (260+)
      Text = Text:gsub ("&25[6-9]","") -- strip invalid xterm codes (256+)
      Text = Text:gsub ("&[^xrgObpcwzRGYBPCWD0-9]", "")  -- rip out hidden garbage
      
      -- make sure we start with & or gsub doesn't work properly
      if Text:sub (1, 1) ~= "&" then
         Text = DEFAULT_COLOUR .. Text
      end -- if

      local text = {}
      local code = ""
      local i = 1
      while i <= #Text do -- iterate over the whole input string
        if Text:sub(i, i):match("&") then -- found a color tag 
          if Text:sub(i+1, i+1):match("(%a)") then -- found a regular color code
            code = Text:sub(i+1, i+1) -- assign the regular code
            local textStart = i+2 -- beginning of text
            while i < #Text and not Text:sub(i+1, i+1):match("&") do i = i + 1 end -- scroll forward to find the next &
            local textEnd = i -- end of text
            text = Text:sub(textStart, textEnd)
          elseif string.match(Text:sub(i+1, i+3), "(%d%d%d)") then -- found an xterm code
            code = Text:sub(i+1, i+3) -- assign the xterm code
            local textStart = i+4 -- beginning of text
            while i < #Text and not Text:sub(i+1, i+1):match("&") do i = i + 1 end -- scroll forward to the next &
            local textEnd = i -- end of text
            text = Text:sub(textStart, textEnd)
          end
          if code and text then
            table.insert(astyles, { text = text,
            length = #text,
            textcolour = colour_conversion [code] or GetNormalColour(WHITE),
            backcolour = GetNormalColour(BLACK) })
          end
        end
        i = i + 1
      end
      return astyles
   end -- if any colour codes at all

   -- No colour codes, create a single style.
   return { { text = Text, 
      length = #Text, 
      textcolour = GetNormalColour (WHITE),
      backcolour = GetNormalColour (BLACK) } }
end  -- function ColoursToStyles

-- strip all lotj color codes from a string
function strip_colours (s)
   s = s:gsub ("&%-", "~")    -- fix tildes
   s = s:gsub ("&&", "\0")  -- change && to 0x00
   s = s:gsub ("&%d%d%d", "") -- strip xterm color codes
   s = s:gsub ("&%a([^&]*)", "%1") -- strip normal color codes
   s = s:gsub ("&[^xrgObpcwzRGYBPCWD]", "")  -- rip out hidden garbage
   return (s:gsub ("%z", "&")) -- put & back
end -- strip_colours

-- returns a string with embedded ansi codes
function stylesToANSI (styles)
   local line = {}
   local reinit = true
   for _,v in ipairs (styles) do
      if ANSI_colours[v.textcolour] then
         table.insert(line, ANSI_colours[v.textcolour])
      elseif colours_extended[v.textcolour] then -- use 256 color xterm ansi when necessary
         table.insert(line, ANSI(38,5,colours_extended[v.textcolour]))
      elseif reinit then -- limit performance damage
         reinit = false
         init_ansi()
      end
      table.insert(line, v.text)
   end
   table.insert(line, ANSI(0))
   return table.concat(line)
end