#! /usr/bin/lua

local file = assert( io.open( arg[ 1 ] ) )
local contents = file:read( "*all" )
file:close()

local bold = false
local fg = 7
local bg = 0

local function setFG( colour )
	return function()
		fg = colour
	end
end

local function setBG( colour )
	return function()
		bg = colour
	end
end

local Colours = {
	[ false ] = {
		[ 0 ] = "333333",
		[ 1 ] = "CA4433",
		[ 2 ] = "178A3A",
		[ 3 ] = "DC7C2A",
		[ 4 ] = "415E87",
		[ 5 ] = "5E468C",
		[ 6 ] = "35789B",
		[ 7 ] = "B6C2C4",
	},

	[ true ] = {
		[ 0 ] = "666666",
		[ 1 ] = "FF2954",
		[ 2 ] = "5DD030",
		[ 3 ] = "FAFC4F",
		[ 4 ] = "3581E1",
		[ 5 ] = "875FFF",
		[ 6 ] = "29FBFF",
		[ 7 ] = "CEDBDE",
	},
}

local function hex( colour, bold )
	return Colours[ bold ][ colour ]
end

local Escapes = {
	[ "0" ] = function()
		bold = false
		fg = 7
		bg = 0
	end,

	[ "1" ] = function()
		bold = true
	end,

	[ "30" ] = setFG( 0 ),
	[ "31" ] = setFG( 1 ),
	[ "32" ] = setFG( 2 ),
	[ "33" ] = setFG( 3 ),
	[ "34" ] = setFG( 4 ),
	[ "35" ] = setFG( 5 ),
	[ "36" ] = setFG( 6 ),
	[ "37" ] = setFG( 7 ),
}

local function handleEscape( escape )
	for code in escape:gmatch( "(%d+)" ) do
		if Escapes[ code ] then
			Escapes[ code ]()
		end
	end

	return ( [[</span><span style="color: #%s; font-weight: %s">]] ):format(
		hex( fg, bold ),
		bold and "bold" or "normal"
	)
end

contents = contents:gsub( "&", "&amp;" ):gsub( "<", "&lt;" ):gsub( ">", "&gt;" )
contents = ( contents .. "\27[m" ):gsub( "(.-)\27%[([%d;]*)m", function( text, escape )
	return text .. handleEscape( escape )
end )

print( "<style>body { background: #1a1a1a; font-family: monospace; white-space: pre; }</style>" )
print( contents )