if not modules then modules = { } end modules ['pret-pas'] = {
    version   = 1.0,
    comment   = "custom pretty printer for Pascal code",
    author    = "Stefan Müller, Chemnitz DE",
    copyright = "Stefan Müller",
    license   = "see context related readme files"
}

local utf = unicode.utf8

local utfcharacters, utfvalues = string.utfcharacters, string.utfvalues
local utfbyte, utffind = utf.byte, utf.find
local byte, sub, find, match = string.byte, string.sub, string.find, string.match
local texsprint, texwrite = tex.sprint, tex.write
local ctxcatcodes = tex.ctxcatcodes

local buffers = buffers

local changestate, finishstate = buffers.changestate, buffers.finishstate

local visualizer = buffers.newvisualizer("pas")

-- reserved words taken from http://www.freepascal.org/docs-html/ref/refse3.html

visualizer.reservedwords = {
	-- Turbo Pascal
	"absolute", "and", "array", "asm", "begin", "case", "const", "constructor",
	"destructor", "div", "do", "downto", "else", "end", "file", "for",
	"function", "goto", "if", "implementation", "in", "inherited", "inline",
	"interface", "label", "mod", "nil", "not", "object", "of", "on", "operator",
	"or", "packed", "procedure", "program", "record", "reintroduce", "repeat",
	"self", "set", "shl", "shr", "string", "then", "to", "type", "unit",
	"until", "uses", "var", "while", "with", "xor",

	-- Free Pascal
	-- these are not bold type (keeping them, just in case)
	-- "dispose", "exit", "false", "new", "true",

	-- Object Pascal
    "as", "class", "dispinterface", "except", "exports", "finalization",
	"finally", "initialization", "inline", "is", "library", "on", "out",
	"packed", "property", "raise", "resourcestring", "threadvar", "try",

	-- Modifiers
	-- some of these are only bold in specific places (this is deliberately
	-- ignored)
	"absolute", "abstract", "alias", "assembler", "cdecl", "cppdecl", "default",
	"export", "external", "far", "far16", "forward", "index", "local", "name", 
	"near", "nostackframe", "oldfpccall", "override", "pascal", "private",
	"protected", "public", "published", "read", "register", "reintroduce",
	"safecall", "softfloat", "stdcall", "virtual", "write"
}

local known_words = { }

for k,v in next, visualizer.reservedwords do
    known_words[v] = k
end

local colors = {
    "prettyone", -- red
    "prettytwo", -- green
    "prettythree", -- blue
    "prettyfour", -- yellow
}

local states = {
    ['"']=1, ["'"]=1, ["[["] = 1, ["]]"] = 1,
    ['+']=1, ['-']=1, ['*']=1, ['/']=1, ['%']=1, ['^']=1,
    ["("] = 3, [")"] = 3, ["["] = 3, ["]"] = 3,
    ['--']=4,
}

local function flush_pas_word(word)
    if word then
        local id = known_words[word]
        if id then
			tex.sprint(tex.ctxcatcodes,"\{\\bf ")
            tex.write(word)
			tex.sprint(tex.ctxcatcodes,"\}")
        else
            tex.write(word)
        end
    end
end

local incomment, inlongstring = false, false
local incompdirec, inasm = false, false

function visualizer.reset()
    incomment, inlongstring = false, false
	incompdirec, inasm = false, false
end

local function written(state,c,i)
    if c == " " then
        state = finishstate(state)
        texsprint(ctxcatcodes,"\\obs")
    elseif c == "\t" then
        state = finishstate(state)
        texsprint(ctxcatcodes,"\\obs")
        if buffers.visualizers.enabletab then
            texsprint(ctxcatcodes,rep("\\obs ",i%buffers.visualizers.tablength))
        end
    else
        texwrite(c)
    end
    return state, 0
end

function visualizer.flush_line(str, nested)
--[[
    buffers.currentcolors = colors
	local identifier = nil
	for c in string.utfcharacters(str) do
		if string.string.find(c, "^[%a%_]$") then
			if identifier then
				identifier = identifier .. c
			else
				identifier = c
			end
		elseif string.string.find(c, "^[%d]$")
			if identifier and #identifier > 1 then
				identifier = identifier .. c
			end
		elseif
			--flush_pas_word(identifier)
			identifier = nil
		end
		tex.write("p")
	end
	--flush_pas_word(identifier)
	identifier = nil
]]
    local state, instr, inesc, word = 0, false, false, nil
    buffers.currentcolors = colors
    local code, comment = match(str,"^(.-)%-%-%[%[(.*)$")
    if comment then
        -- process the code and then flush the comment
    elseif incomment then
        comment, code = match(str,"^(.-)%]%](.*)$")
        if comment then
            -- flush the comment and then process the code
            for c in utfcharacters(comment) do
                if c == " " then texsprint(ctxcatcodes,"\\obs") else texwrite(c) end
            end
            state = changestate(states['--'], state)
            texwrite("]]")
            state = finishstate(state)
            incomment = false
        else
            for c in utfcharacters(str) do
                if c == " " then texsprint(ctxcatcodes,"\\obs") else texwrite(c) end
            end
        end
        comment = nil
    else
        code = str
    end
    if code and code ~= "" then
        local pre, post = match(code,"^(.-)%-%-(.*)$")
        if pre then
            code = pre
        end
        local p, s, i = nil, nil, 0
        for c in utfcharacters(code) do
            i = i + 1
            if instr then
                if p then
                    texwrite(p)
                    p = nil
                end
                if c == s then
                    if inesc then
                        texwrite(c)
                        inesc = false
                    else
                        state = changestate(states[c],state)
                        instr = false
                        texwrite(c)
                        state = finishstate(state)
                    end
                    s = nil
                else
                    if c == "\\" then
                        inesc = not inesc
                    else
                        inesc = false
                    end
                    state, i = written(state,c,i)
                end
            elseif c == "[" then
                if word then
                    texwrite(word)
                    word = nil
                end
                if p == "[" then
                    inlongstring = true
                    state = changestate(states["[["],state)
                    texwrite(p,c)
                    state = finishstate(state)
                    p = nil
                else
                    if p then
                        state, i = written(state,p,i)
                    end
                    p = c
                end
            elseif c == "]" then
                if word then
                    texwrite(word)
                    word = nil
                end
                if p == "]" then
                    inlongstring = false
                    state = changestate(states["]]"],state)
                    texwrite(p,c)
                    state = finishstate(state)
                    p = nil
                else
                    if p then
                        state, i = written(state,p,i)
                    end
                    p = c
                end
            else
                if p then
                    state = changestate(states[p],state)
                    texwrite(p)
                    state = finishstate(state)
                    p = nil
                end
                if c == " " or c == "\t" then
                    if word then
                        flush_pas_word(word)
                        word = nil
                    end
                    state, i = written(state,c,i)
                elseif inlongstring then
                    state, i = written(state,c,i)
                elseif c == '"' or c == "'" then
					if word then
						flush_pas_word(word)
						word = nil
					end
                    instr = true
                    state = changestate(states[c],state)
                    state, i = written(state,c,i)
                    state = finishstate(state)
                    s = c
                elseif find(c,"^[%a]$") then
                    state = finishstate(state)
                    if word then word = word .. c else word = c end
                elseif word and (#word > 1) and find(c,"^[%d%.%_]$") then
                    if word then word = word .. c else word = c end
                else
                    flush_pas_word(word)
                    word = nil
                    state = changestate(states[c],state)
                    texwrite(c)
                    instr = (c == '"')
                end
            end
        end
        if p then
            texwrite(p)
            -- state, i = written(state,p,i)
            p = nil
        end
        flush_pas_word(word)
        if post then
            state = changestate(states['--'], state)
            texwrite("--")
            state = finishstate(state)
            for c in utfcharacters(post) do
                state, i = written(state,c,i)
            end
        end
    end
    if comment then
        incomment = true
        state = changestate(states['--'], state)
        texwrite("[[")
        state = finishstate(state)
     -- texwrite(comment) -- maybe also split and
        for c in utfcharacters(comment) do
            state, i = written(state,c,i)
        end
    end
    state = finishstate(state)
end