-- advtrains track map generator
-- Usage: lua main.lua path/to/world

-- Viewport maximum coordinate in all directions
local maxc = 5000

-- embed an image called "world.png"
local wimg = false
-- image file resolution (not world resolution!)
local wimresx = 3000
local wimresy = 3000
-- one pixel is ... nodes
local wimscale = 4

-- y ranges and line colors
-- Minimum y level drawn
local drminy = -30
-- Color of min y level
local colminy = {r=0, g=0, b=255}
-- Intermediate color
local colmedy = {r=255, g=0, b=0}
-- Maximum y level drawn
local drmaxy = 80
-- Color of max y level
local colmaxy = {r=255, g=255, b=0}


datapath = (arg[1] or "").."/"


--Constant for maximum connection value/division of the circle
AT_CMAX = 16

advtrains = {}
minetest = {}
core = minetest

--table for track nodes/connections
trackconns = {}

-- math library seems to be missing this function
math.hypot = function(a,b) return math.sqrt(a*a + b*b) end

-- need to declare this for trackdefs
function attrans(str) return str end

-- pos to string
local function pts(pos)
	return pos.x .. "," .. pos.y .. "," .. pos.z
end

--Advtrains dump (special treatment of pos and sigd)
function atdump(t, intend)
	local str
	if type(t)=="table" then
		if t.x and t.y and t.z then
			str=minetest.pos_to_string(t)
		elseif t.p and t.s then -- interlocking sigd
			str="S["..minetest.pos_to_string(t.p).."/"..t.s.."]"
		else
			str="{"
			local intd = (intend or "") .. "  "
			for k,v in pairs(t) do
				if type(k)~="string" or not string.match(k, "^path[_]?") then
					-- do not print anything path-related
					str = str .. "\n" .. intd .. atdump(k, intd) .. " = " ..atdump(v, intd)
				end
			end
			str = str .. "\n" .. (intend or "") .. "}"
		end
	elseif type(t)=="boolean" then
		if t then
			str="true"
		else
			str="false"
		end
	elseif type(t)=="function" then
		str="<function>"
	elseif type(t)=="userdata" then
		str="<userdata>"
	else
		str=""..t
	end
	return str
end

dofile("vector.lua")
dofile("serialize.lua")
dofile("helpers.lua")
dofile("tracks.lua")
dofile("track_defs.lua")

dofile("nodedb.lua")


function parse_args(argv) 
	local i = 1
	local no_trains = false
	local datapath, mappath
	while i <= #argv do
		local a = argv[i]
		if (a == "-m") or (a == "--map-file") then
			-- only draw trains – requires specifying an already drawn file
			i = i+1
			if not argv[i] then
				error(("missing filename after `%s'"):format(a))
			end
			mappath = argv[i]
		elseif (a == "-t") or (a == "--no-trains") then
			-- do not draw trains
			no_trains = true
		else
			datapath = a
		end
		i = i + 1
	end
	return datapath, mappath, no_trains
end

datapath, mappath, no_trains = parse_args(arg)

-- Load saves
local file, err = io.open(datapath.."advtrains", "r")
local tbl = minetest.deserialize(file:read("*a"))
if type(tbl) ~= "table" then
	error("not a table")
end
if tbl.version then
	advtrains.trains = tbl.trains
	if not mappath then
		advtrains.ndb.load_data(tbl.ndb)
	end
	
else
	error("Incompatible save format!")
end
file:close()

-- open svg file

local svgfile = io.open(datapath.."out.svg", "w")


if mappath then
	mapfile = io.open(mappath, "r")
	cont = mapfile:read("*a"):sub(1, -7) -- remove </svg> end tag
	svgfile:write(cont)
else
	svgfile:write([[
<?xml version="1.0" standalone="no" ?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 20010904//EN"
  "http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd">
<svg width="1024" height="800" xmlns="http://www.w3.org/2000/svg"