FNT -> Scopes S Expressions converter

fnt2scopes.lua

local filename = arg[1]
local output = 
[[
using import struct
struct FNTCharInfo plain
    id       : i32
    x        : i32
    y        : i32
    width    : i32
    height   : i32
    xoffset  : i32
    yoffset  : i32
    xadvance : i32
    channel  : i32

let font =
    arrayof FNTCharInfo
]]

local function makeCharEntry(info)
    local indentation = "        "
    local result =
        indentation ..
        "FNTCharInfo " ..
        "(id = " .. info.id .. ") " ..
        "(x = " .. info.x .. ") " ..
        "(y = " .. info.y .. ") " ..
        "(width = " .. info.width .. ") " ..
        "(height = " .. info.height .. ") " ..
        "(xoffset = " .. info.xoffset .. ") " ..
        "(yoffset = " .. info.yoffset .. ") " ..
        "(xadvance = " .. info.xadvance .. ") " ..
        "(channel = " .. info.chnl .. ")"
    return result
end

local lpeg = require("lpeg")
local re = require("re")
local pattern = 
    [[
        S  <- {| 'char id=' id %s+ 
              'x=' x %s+ 
              'y=' y %s+ 
              'width=' width %s+
              'height=' height %s+
              'xoffset=' xoffset %s+
              'yoffset=' yoffset %s+
              'xadvance=' xadvance %s+
              'page=' page %s+
              'chnl=' chnl |}
        si32     <- '-'? %d+
        id       <- {:id: si32 :}
        x        <- {:x: si32 :}
        y        <- {:y: si32 :}
        width    <- {:width: si32 :}
        height   <- {:height: si32 :}
        xoffset  <- {:xoffset: si32 :}
        yoffset  <- {:yoffset: si32 :}
        xadvance <- {:xadvance: si32 :}
        page     <- si32
        chnl     <- {:chnl: si32 :}
    ]]

local expression = re.compile(pattern)

local file = io.open(filename)
local line = file:read("*line")

io.write(output)
while (line) do
    local cap = lpeg.match(expression, line)
    if cap then
        print (makeCharEntry(cap))
    end
    line = file:read("*line")
end